From 62eb29526b48d20704668a2fdf97a49d01bf52ce Mon Sep 17 00:00:00 2001 From: Rasmus Villemoes Date: Tue, 22 Mar 2022 14:38:33 -0700 Subject: linux/kthread.h: remove unused macros Ever since these macros were introduced in commit b56c0d8937e6 ("kthread: implement kthread_worker"), there has been precisely one user (commit 4d115420707a, "NVMe: Async IO queue deletion"), and that user went away in 2016 with db3cbfff5bcc ("NVMe: IO queue deletion re-write"). Apart from being unused, these macros are also awkward to use (which may contribute to them not being used): Having a way to statically (or on-stack) allocating the storage for the struct kthread_worker itself doesn't help much, since obviously one needs to have some code for actually _spawning_ the worker thread, which must have error checking. And these days we have the kthread_create_worker() interface which both allocates the struct kthread_worker and spawns the kthread. Link: https://lkml.kernel.org/r/20220314145343.494694-1-linux@rasmusvillemoes.dk Signed-off-by: Rasmus Villemoes Acked-by: Tejun Heo Cc: "Eric W. Biederman" Cc: Petr Mladek Cc: David Hildenbrand Cc: Yafang Shao Cc: Cai Huoqing Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/kthread.h | 22 ---------------------- 1 file changed, 22 deletions(-) (limited to 'include/linux') diff --git a/include/linux/kthread.h b/include/linux/kthread.h index 3df4ea04716f..de5d75bafd66 100644 --- a/include/linux/kthread.h +++ b/include/linux/kthread.h @@ -141,12 +141,6 @@ struct kthread_delayed_work { struct timer_list timer; }; -#define KTHREAD_WORKER_INIT(worker) { \ - .lock = __RAW_SPIN_LOCK_UNLOCKED((worker).lock), \ - .work_list = LIST_HEAD_INIT((worker).work_list), \ - .delayed_work_list = LIST_HEAD_INIT((worker).delayed_work_list),\ - } - #define KTHREAD_WORK_INIT(work, fn) { \ .node = LIST_HEAD_INIT((work).node), \ .func = (fn), \ @@ -158,9 +152,6 @@ struct kthread_delayed_work { TIMER_IRQSAFE), \ } -#define DEFINE_KTHREAD_WORKER(worker) \ - struct kthread_worker worker = KTHREAD_WORKER_INIT(worker) - #define DEFINE_KTHREAD_WORK(work, fn) \ struct kthread_work work = KTHREAD_WORK_INIT(work, fn) @@ -168,19 +159,6 @@ struct kthread_delayed_work { struct kthread_delayed_work dwork = \ KTHREAD_DELAYED_WORK_INIT(dwork, fn) -/* - * kthread_worker.lock needs its own lockdep class key when defined on - * stack with lockdep enabled. Use the following macros in such cases. - */ -#ifdef CONFIG_LOCKDEP -# define KTHREAD_WORKER_INIT_ONSTACK(worker) \ - ({ kthread_init_worker(&worker); worker; }) -# define DEFINE_KTHREAD_WORKER_ONSTACK(worker) \ - struct kthread_worker worker = KTHREAD_WORKER_INIT_ONSTACK(worker) -#else -# define DEFINE_KTHREAD_WORKER_ONSTACK(worker) DEFINE_KTHREAD_WORKER(worker) -#endif - extern void __kthread_init_worker(struct kthread_worker *worker, const char *name, struct lock_class_key *key); -- cgit v1.2.3 From bf507030f312c68fdbb17c2d33f317cda109a484 Mon Sep 17 00:00:00 2001 From: NeilBrown Date: Tue, 22 Mar 2022 14:38:48 -0700 Subject: doc: convert 'subsection' to 'section' in gfp.h Patch series "Remove remaining parts of congestion tracking code", v2. This patch (of 11): Various DOC: sections in gfp.h have subsection headers (~~~) but the place where they are included in mm-api.rst does not have section, only chapters. So convert to section headers (---) to avoid confusion. Specifically if sections are added later in mm-api.rst, an error results. Link: https://lkml.kernel.org/r/164549971112.9187.16871723439770288255.stgit@noble.brown Link: https://lkml.kernel.org/r/164549983733.9187.17894407453436115822.stgit@noble.brown Signed-off-by: NeilBrown Cc: Jan Kara Cc: Wu Fengguang Cc: Jaegeuk Kim Cc: Chao Yu Cc: Jeff Layton Cc: Ilya Dryomov Cc: Miklos Szeredi Cc: Trond Myklebust Cc: Anna Schumaker Cc: Ryusuke Konishi Cc: Darrick J. Wong Cc: Philipp Reisner Cc: Lars Ellenberg Cc: Paolo Valente Cc: Jens Axboe Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/gfp.h | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) (limited to 'include/linux') diff --git a/include/linux/gfp.h b/include/linux/gfp.h index 80f63c862be5..20f6fbe12993 100644 --- a/include/linux/gfp.h +++ b/include/linux/gfp.h @@ -79,7 +79,7 @@ struct vm_area_struct; * DOC: Page mobility and placement hints * * Page mobility and placement hints - * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + * --------------------------------- * * These flags provide hints about how mobile the page is. Pages with similar * mobility are placed within the same pageblocks to minimise problems due @@ -112,7 +112,7 @@ struct vm_area_struct; * DOC: Watermark modifiers * * Watermark modifiers -- controls access to emergency reserves - * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + * ------------------------------------------------------------ * * %__GFP_HIGH indicates that the caller is high-priority and that granting * the request is necessary before the system can make forward progress. @@ -144,7 +144,7 @@ struct vm_area_struct; * DOC: Reclaim modifiers * * Reclaim modifiers - * ~~~~~~~~~~~~~~~~~ + * ----------------- * Please note that all the following flags are only applicable to sleepable * allocations (e.g. %GFP_NOWAIT and %GFP_ATOMIC will ignore them). * @@ -224,7 +224,7 @@ struct vm_area_struct; * DOC: Action modifiers * * Action modifiers - * ~~~~~~~~~~~~~~~~ + * ---------------- * * %__GFP_NOWARN suppresses allocation failure reports. * @@ -256,7 +256,7 @@ struct vm_area_struct; * DOC: Useful GFP flag combinations * * Useful GFP flag combinations - * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + * ---------------------------- * * Useful GFP flag combinations that are commonly used. It is recommended * that subsystems start with one of these combinations and then set/clear -- cgit v1.2.3 From 84dacdbd5352bfef82423760fa2e8bffaeef9e05 Mon Sep 17 00:00:00 2001 From: NeilBrown Date: Tue, 22 Mar 2022 14:38:51 -0700 Subject: mm: document and polish read-ahead code Add some "big-picture" documentation for read-ahead and polish the code to make it fit this documentation. The meaning of ->async_size is clarified to match its name. i.e. Any request to ->readahead() has a sync part and an async part. The caller will wait for the sync pages to complete, but will not wait for the async pages. The first async page is still marked PG_readahead Note that the current function names page_cache_sync_ra() and page_cache_async_ra() are misleading. All ra request are partly sync and partly async, so either part can be empty. A page_cache_sync_ra() request will usually set ->async_size non-zero, implying it is not all synchronous. When a non-zero req_count is passed to page_cache_async_ra(), the implication is that some prefix of the request is synchronous, though the calculation made there is incorrect - I haven't tried to fix it. Link: https://lkml.kernel.org/r/164549983734.9187.11586890887006601405.stgit@noble.brown Signed-off-by: NeilBrown Cc: Anna Schumaker Cc: Chao Yu Cc: Darrick J. Wong Cc: Ilya Dryomov Cc: Jaegeuk Kim Cc: Jan Kara Cc: Jeff Layton Cc: Jens Axboe Cc: Lars Ellenberg Cc: Miklos Szeredi Cc: Paolo Valente Cc: Philipp Reisner Cc: Ryusuke Konishi Cc: Trond Myklebust Cc: Wu Fengguang Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- Documentation/core-api/mm-api.rst | 19 +++++++- Documentation/filesystems/vfs.rst | 16 ++++--- include/linux/fs.h | 9 +++- mm/readahead.c | 99 +++++++++++++++++++++++++++++++++++++++ 4 files changed, 133 insertions(+), 10 deletions(-) (limited to 'include/linux') diff --git a/Documentation/core-api/mm-api.rst b/Documentation/core-api/mm-api.rst index 395835f9289f..f5b2f92822c8 100644 --- a/Documentation/core-api/mm-api.rst +++ b/Documentation/core-api/mm-api.rst @@ -58,15 +58,30 @@ Virtually Contiguous Mappings File Mapping and Page Cache =========================== -.. kernel-doc:: mm/readahead.c - :export: +Filemap +------- .. kernel-doc:: mm/filemap.c :export: +Readahead +--------- + +.. kernel-doc:: mm/readahead.c + :doc: Readahead Overview + +.. kernel-doc:: mm/readahead.c + :export: + +Writeback +--------- + .. kernel-doc:: mm/page-writeback.c :export: +Truncate +-------- + .. kernel-doc:: mm/truncate.c :export: diff --git a/Documentation/filesystems/vfs.rst b/Documentation/filesystems/vfs.rst index bf5c48066fac..b4a0baa46dcc 100644 --- a/Documentation/filesystems/vfs.rst +++ b/Documentation/filesystems/vfs.rst @@ -806,12 +806,16 @@ cache in your filesystem. The following members are defined: object. The pages are consecutive in the page cache and are locked. The implementation should decrement the page refcount after starting I/O on each page. Usually the page will be - unlocked by the I/O completion handler. If the filesystem decides - to stop attempting I/O before reaching the end of the readahead - window, it can simply return. The caller will decrement the page - refcount and unlock the remaining pages for you. Set PageUptodate - if the I/O completes successfully. Setting PageError on any page - will be ignored; simply unlock the page if an I/O error occurs. + unlocked by the I/O completion handler. The set of pages are + divided into some sync pages followed by some async pages, + rac->ra->async_size gives the number of async pages. The + filesystem should attempt to read all sync pages but may decide + to stop once it reaches the async pages. If it does decide to + stop attempting I/O, it can simply return. The caller will + remove the remaining pages from the address space, unlock them + and decrement the page refcount. Set PageUptodate if the I/O + completes successfully. Setting PageError on any page will be + ignored; simply unlock the page if an I/O error occurs. ``readpages`` called by the VM to read pages associated with the address_space diff --git a/include/linux/fs.h b/include/linux/fs.h index e2d892b201b0..8b5c486bd4a2 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -930,10 +930,15 @@ struct fown_struct { * struct file_ra_state - Track a file's readahead state. * @start: Where the most recent readahead started. * @size: Number of pages read in the most recent readahead. - * @async_size: Start next readahead when this many pages are left. - * @ra_pages: Maximum size of a readahead request. + * @async_size: Numer of pages that were/are not needed immediately + * and so were/are genuinely "ahead". Start next readahead when + * the first of these pages is accessed. + * @ra_pages: Maximum size of a readahead request, copied from the bdi. * @mmap_miss: How many mmap accesses missed in the page cache. * @prev_pos: The last byte in the most recent read request. + * + * When this structure is passed to ->readahead(), the "most recent" + * readahead means the current readahead. */ struct file_ra_state { pgoff_t start; diff --git a/mm/readahead.c b/mm/readahead.c index cf0dcf89eb69..73b2bc5302e0 100644 --- a/mm/readahead.c +++ b/mm/readahead.c @@ -8,6 +8,105 @@ * Initial version. */ +/** + * DOC: Readahead Overview + * + * Readahead is used to read content into the page cache before it is + * explicitly requested by the application. Readahead only ever + * attempts to read pages that are not yet in the page cache. If a + * page is present but not up-to-date, readahead will not try to read + * it. In that case a simple ->readpage() will be requested. + * + * Readahead is triggered when an application read request (whether a + * systemcall or a page fault) finds that the requested page is not in + * the page cache, or that it is in the page cache and has the + * %PG_readahead flag set. This flag indicates that the page was loaded + * as part of a previous read-ahead request and now that it has been + * accessed, it is time for the next read-ahead. + * + * Each readahead request is partly synchronous read, and partly async + * read-ahead. This is reflected in the struct file_ra_state which + * contains ->size being to total number of pages, and ->async_size + * which is the number of pages in the async section. The first page in + * this async section will have %PG_readahead set as a trigger for a + * subsequent read ahead. Once a series of sequential reads has been + * established, there should be no need for a synchronous component and + * all read ahead request will be fully asynchronous. + * + * When either of the triggers causes a readahead, three numbers need to + * be determined: the start of the region, the size of the region, and + * the size of the async tail. + * + * The start of the region is simply the first page address at or after + * the accessed address, which is not currently populated in the page + * cache. This is found with a simple search in the page cache. + * + * The size of the async tail is determined by subtracting the size that + * was explicitly requested from the determined request size, unless + * this would be less than zero - then zero is used. NOTE THIS + * CALCULATION IS WRONG WHEN THE START OF THE REGION IS NOT THE ACCESSED + * PAGE. + * + * The size of the region is normally determined from the size of the + * previous readahead which loaded the preceding pages. This may be + * discovered from the struct file_ra_state for simple sequential reads, + * or from examining the state of the page cache when multiple + * sequential reads are interleaved. Specifically: where the readahead + * was triggered by the %PG_readahead flag, the size of the previous + * readahead is assumed to be the number of pages from the triggering + * page to the start of the new readahead. In these cases, the size of + * the previous readahead is scaled, often doubled, for the new + * readahead, though see get_next_ra_size() for details. + * + * If the size of the previous read cannot be determined, the number of + * preceding pages in the page cache is used to estimate the size of + * a previous read. This estimate could easily be misled by random + * reads being coincidentally adjacent, so it is ignored unless it is + * larger than the current request, and it is not scaled up, unless it + * is at the start of file. + * + * In general read ahead is accelerated at the start of the file, as + * reads from there are often sequential. There are other minor + * adjustments to the read ahead size in various special cases and these + * are best discovered by reading the code. + * + * The above calculation determines the readahead, to which any requested + * read size may be added. + * + * Readahead requests are sent to the filesystem using the ->readahead() + * address space operation, for which mpage_readahead() is a canonical + * implementation. ->readahead() should normally initiate reads on all + * pages, but may fail to read any or all pages without causing an IO + * error. The page cache reading code will issue a ->readpage() request + * for any page which ->readahead() does not provided, and only an error + * from this will be final. + * + * ->readahead() will generally call readahead_page() repeatedly to get + * each page from those prepared for read ahead. It may fail to read a + * page by: + * + * * not calling readahead_page() sufficiently many times, effectively + * ignoring some pages, as might be appropriate if the path to + * storage is congested. + * + * * failing to actually submit a read request for a given page, + * possibly due to insufficient resources, or + * + * * getting an error during subsequent processing of a request. + * + * In the last two cases, the page should be unlocked to indicate that + * the read attempt has failed. In the first case the page will be + * unlocked by the caller. + * + * Those pages not in the final ``async_size`` of the request should be + * considered to be important and ->readahead() should not fail them due + * to congestion or temporary resource unavailability, but should wait + * for necessary resources (e.g. memory or indexing information) to + * become available. Pages in the final ``async_size`` may be + * considered less urgent and failure to read them is more acceptable. + * They will eventually be read individually using ->readpage(). + */ + #include #include #include -- cgit v1.2.3 From 6df25e58532be7a4cd6fb15bcd85805947402d91 Mon Sep 17 00:00:00 2001 From: NeilBrown Date: Tue, 22 Mar 2022 14:39:01 -0700 Subject: nfs: remove reliance on bdi congestion The bdi congestion tracking in not widely used and will be removed. NFS is one of a small number of filesystems that uses it, setting just the async (write) congestion flag at what it determines are appropriate times. The only remaining effect of the async flag is to cause (some) WB_SYNC_NONE writes to be skipped. So instead of setting the flag, set an internal flag and change: - .writepages to do nothing if WB_SYNC_NONE and the flag is set - .writepage to return AOP_WRITEPAGE_ACTIVATE if WB_SYNC_NONE and the flag is set. The writepages change causes a behavioural change in that pageout() can now return PAGE_ACTIVATE instead of PAGE_KEEP, so SetPageActive() will be called on the page which (I think) wil further delay the next attempt at writeout. This might be a good thing. Link: https://lkml.kernel.org/r/164549983738.9187.3972219847989393182.stgit@noble.brown Signed-off-by: NeilBrown Cc: Anna Schumaker Cc: Chao Yu Cc: Darrick J. Wong Cc: Ilya Dryomov Cc: Jaegeuk Kim Cc: Jan Kara Cc: Jeff Layton Cc: Jens Axboe Cc: Lars Ellenberg Cc: Miklos Szeredi Cc: Paolo Valente Cc: Philipp Reisner Cc: Ryusuke Konishi Cc: Trond Myklebust Cc: Wu Fengguang Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/nfs/write.c | 14 +++++++++++--- include/linux/nfs_fs_sb.h | 1 + 2 files changed, 12 insertions(+), 3 deletions(-) (limited to 'include/linux') diff --git a/fs/nfs/write.c b/fs/nfs/write.c index 987a187bd39a..7c986164018e 100644 --- a/fs/nfs/write.c +++ b/fs/nfs/write.c @@ -417,7 +417,7 @@ static void nfs_set_page_writeback(struct page *page) if (atomic_long_inc_return(&nfss->writeback) > NFS_CONGESTION_ON_THRESH) - set_bdi_congested(inode_to_bdi(inode), BLK_RW_ASYNC); + nfss->write_congested = 1; } static void nfs_end_page_writeback(struct nfs_page *req) @@ -433,7 +433,7 @@ static void nfs_end_page_writeback(struct nfs_page *req) end_page_writeback(req->wb_page); if (atomic_long_dec_return(&nfss->writeback) < NFS_CONGESTION_OFF_THRESH) - clear_bdi_congested(inode_to_bdi(inode), BLK_RW_ASYNC); + nfss->write_congested = 0; } /* @@ -672,6 +672,10 @@ static int nfs_writepage_locked(struct page *page, struct inode *inode = page_file_mapping(page)->host; int err; + if (wbc->sync_mode == WB_SYNC_NONE && + NFS_SERVER(inode)->write_congested) + return AOP_WRITEPAGE_ACTIVATE; + nfs_inc_stats(inode, NFSIOS_VFSWRITEPAGE); nfs_pageio_init_write(&pgio, inode, 0, false, &nfs_async_write_completion_ops); @@ -719,6 +723,10 @@ int nfs_writepages(struct address_space *mapping, struct writeback_control *wbc) int priority = 0; int err; + if (wbc->sync_mode == WB_SYNC_NONE && + NFS_SERVER(inode)->write_congested) + return 0; + nfs_inc_stats(inode, NFSIOS_VFSWRITEPAGES); if (!(mntflags & NFS_MOUNT_WRITE_EAGER) || wbc->for_kupdate || @@ -1893,7 +1901,7 @@ static void nfs_commit_release_pages(struct nfs_commit_data *data) } nfss = NFS_SERVER(data->inode); if (atomic_long_read(&nfss->writeback) < NFS_CONGESTION_OFF_THRESH) - clear_bdi_congested(inode_to_bdi(data->inode), BLK_RW_ASYNC); + nfss->write_congested = 0; nfs_init_cinfo(&cinfo, data->inode, data->dreq); nfs_commit_end(cinfo.mds); diff --git a/include/linux/nfs_fs_sb.h b/include/linux/nfs_fs_sb.h index ca0959e51e81..6aa2a200676a 100644 --- a/include/linux/nfs_fs_sb.h +++ b/include/linux/nfs_fs_sb.h @@ -138,6 +138,7 @@ struct nfs_server { struct nlm_host *nlm_host; /* NLM client handle */ struct nfs_iostats __percpu *io_stats; /* I/O statistics */ atomic_long_t writeback; /* number of writeback pages */ + unsigned int write_congested;/* flag set when writeback gets too high */ unsigned int flags; /* various flags */ /* The following are for internal use only. Also see uapi/linux/nfs_mount.h */ -- cgit v1.2.3 From fe55d563d4174f13839a9b7ef7309da5031b5d93 Mon Sep 17 00:00:00 2001 From: NeilBrown Date: Tue, 22 Mar 2022 14:39:07 -0700 Subject: remove inode_congested() inode_congested() reports if the backing-device for the inode is congested. No bdi reports congestion any more, so this always returns 'false'. So remove inode_congested() and related functions, and remove the call sites, assuming that inode_congested() always returns 'false'. Link: https://lkml.kernel.org/r/164549983741.9187.2174285592262191311.stgit@noble.brown Signed-off-by: NeilBrown Cc: Anna Schumaker Cc: Chao Yu Cc: Darrick J. Wong Cc: Ilya Dryomov Cc: Jaegeuk Kim Cc: Jan Kara Cc: Jeff Layton Cc: Jens Axboe Cc: Lars Ellenberg Cc: Miklos Szeredi Cc: Paolo Valente Cc: Philipp Reisner Cc: Ryusuke Konishi Cc: Trond Myklebust Cc: Wu Fengguang Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/fs-writeback.c | 37 ------------------------------------- include/linux/backing-dev.h | 22 ---------------------- mm/fadvise.c | 5 ++--- mm/readahead.c | 6 ------ mm/vmscan.c | 17 +---------------- 5 files changed, 3 insertions(+), 84 deletions(-) (limited to 'include/linux') diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c index f8d7fe6db989..42a3dfad40b8 100644 --- a/fs/fs-writeback.c +++ b/fs/fs-writeback.c @@ -893,43 +893,6 @@ void wbc_account_cgroup_owner(struct writeback_control *wbc, struct page *page, } EXPORT_SYMBOL_GPL(wbc_account_cgroup_owner); -/** - * inode_congested - test whether an inode is congested - * @inode: inode to test for congestion (may be NULL) - * @cong_bits: mask of WB_[a]sync_congested bits to test - * - * Tests whether @inode is congested. @cong_bits is the mask of congestion - * bits to test and the return value is the mask of set bits. - * - * If cgroup writeback is enabled for @inode, the congestion state is - * determined by whether the cgwb (cgroup bdi_writeback) for the blkcg - * associated with @inode is congested; otherwise, the root wb's congestion - * state is used. - * - * @inode is allowed to be NULL as this function is often called on - * mapping->host which is NULL for the swapper space. - */ -int inode_congested(struct inode *inode, int cong_bits) -{ - /* - * Once set, ->i_wb never becomes NULL while the inode is alive. - * Start transaction iff ->i_wb is visible. - */ - if (inode && inode_to_wb_is_valid(inode)) { - struct bdi_writeback *wb; - struct wb_lock_cookie lock_cookie = {}; - bool congested; - - wb = unlocked_inode_to_wb_begin(inode, &lock_cookie); - congested = wb_congested(wb, cong_bits); - unlocked_inode_to_wb_end(inode, &lock_cookie); - return congested; - } - - return wb_congested(&inode_to_bdi(inode)->wb, cong_bits); -} -EXPORT_SYMBOL_GPL(inode_congested); - /** * wb_split_bdi_pages - split nr_pages to write according to bandwidth * @wb: target bdi_writeback to split @nr_pages to diff --git a/include/linux/backing-dev.h b/include/linux/backing-dev.h index 483979c1b9f4..860b675c2929 100644 --- a/include/linux/backing-dev.h +++ b/include/linux/backing-dev.h @@ -162,7 +162,6 @@ struct bdi_writeback *wb_get_create(struct backing_dev_info *bdi, gfp_t gfp); void wb_memcg_offline(struct mem_cgroup *memcg); void wb_blkcg_offline(struct blkcg *blkcg); -int inode_congested(struct inode *inode, int cong_bits); /** * inode_cgwb_enabled - test whether cgroup writeback is enabled on an inode @@ -390,29 +389,8 @@ static inline void wb_blkcg_offline(struct blkcg *blkcg) { } -static inline int inode_congested(struct inode *inode, int cong_bits) -{ - return wb_congested(&inode_to_bdi(inode)->wb, cong_bits); -} - #endif /* CONFIG_CGROUP_WRITEBACK */ -static inline int inode_read_congested(struct inode *inode) -{ - return inode_congested(inode, 1 << WB_sync_congested); -} - -static inline int inode_write_congested(struct inode *inode) -{ - return inode_congested(inode, 1 << WB_async_congested); -} - -static inline int inode_rw_congested(struct inode *inode) -{ - return inode_congested(inode, (1 << WB_sync_congested) | - (1 << WB_async_congested)); -} - static inline int bdi_congested(struct backing_dev_info *bdi, int cong_bits) { return wb_congested(&bdi->wb, cong_bits); diff --git a/mm/fadvise.c b/mm/fadvise.c index d6baa4f451c5..338f16022012 100644 --- a/mm/fadvise.c +++ b/mm/fadvise.c @@ -109,9 +109,8 @@ int generic_fadvise(struct file *file, loff_t offset, loff_t len, int advice) case POSIX_FADV_NOREUSE: break; case POSIX_FADV_DONTNEED: - if (!inode_write_congested(mapping->host)) - __filemap_fdatawrite_range(mapping, offset, endbyte, - WB_SYNC_NONE); + __filemap_fdatawrite_range(mapping, offset, endbyte, + WB_SYNC_NONE); /* * First and last FULL page! Partial pages are deliberately diff --git a/mm/readahead.c b/mm/readahead.c index 8a97bd408cf6..f61943fd1741 100644 --- a/mm/readahead.c +++ b/mm/readahead.c @@ -709,12 +709,6 @@ void page_cache_async_ra(struct readahead_control *ractl, folio_clear_readahead(folio); - /* - * Defer asynchronous read-ahead on IO congestion. - */ - if (inode_read_congested(ractl->mapping->host)) - return; - if (blk_cgroup_congested()) return; diff --git a/mm/vmscan.c b/mm/vmscan.c index 59b14e0d696c..e38de6456cdc 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -989,17 +989,6 @@ static inline int is_page_cache_freeable(struct page *page) return page_count(page) - page_has_private(page) == 1 + page_cache_pins; } -static int may_write_to_inode(struct inode *inode) -{ - if (current->flags & PF_SWAPWRITE) - return 1; - if (!inode_write_congested(inode)) - return 1; - if (inode_to_bdi(inode) == current->backing_dev_info) - return 1; - return 0; -} - /* * We detected a synchronous write error writing a page out. Probably * -ENOSPC. We need to propagate that into the address_space for a subsequent @@ -1201,8 +1190,6 @@ static pageout_t pageout(struct page *page, struct address_space *mapping) } if (mapping->a_ops->writepage == NULL) return PAGE_ACTIVATE; - if (!may_write_to_inode(mapping->host)) - return PAGE_KEEP; if (clear_page_dirty_for_io(page)) { int res; @@ -1578,9 +1565,7 @@ retry: * end of the LRU a second time. */ mapping = page_mapping(page); - if (((dirty || writeback) && mapping && - inode_write_congested(mapping->host)) || - (writeback && PageReclaim(page))) + if (writeback && PageReclaim(page)) stat->nr_congested++; /* -- cgit v1.2.3 From b9b1335e640308acc1b8f26c739b804c80a6c147 Mon Sep 17 00:00:00 2001 From: NeilBrown Date: Tue, 22 Mar 2022 14:39:10 -0700 Subject: remove bdi_congested() and wb_congested() and related functions These functions are no longer useful as no BDIs report congestions any more. Removing the test on bdi_write_contested() in current_may_throttle() could cause a small change in behaviour, but only when PF_LOCAL_THROTTLE is set. So replace the calls by 'false' and simplify the code - and remove the functions. [akpm@linux-foundation.org: fix build] Link: https://lkml.kernel.org/r/164549983742.9187.2570198746005819592.stgit@noble.brown Signed-off-by: NeilBrown Acked-by: Ryusuke Konishi [nilfs] Cc: Anna Schumaker Cc: Chao Yu Cc: Darrick J. Wong Cc: Ilya Dryomov Cc: Jaegeuk Kim Cc: Jan Kara Cc: Jeff Layton Cc: Jens Axboe Cc: Lars Ellenberg Cc: Miklos Szeredi Cc: Paolo Valente Cc: Philipp Reisner Cc: Trond Myklebust Cc: Wu Fengguang Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/block/drbd/drbd_int.h | 3 --- drivers/block/drbd/drbd_req.c | 3 +-- fs/ext2/ialloc.c | 5 ----- fs/nilfs2/segbuf.c | 16 ---------------- fs/xfs/xfs_buf.c | 3 --- include/linux/backing-dev.h | 26 -------------------------- mm/vmscan.c | 4 +--- 7 files changed, 2 insertions(+), 58 deletions(-) (limited to 'include/linux') diff --git a/drivers/block/drbd/drbd_int.h b/drivers/block/drbd/drbd_int.h index f27d5b0f9a0b..f804b1bfb3e6 100644 --- a/drivers/block/drbd/drbd_int.h +++ b/drivers/block/drbd/drbd_int.h @@ -638,9 +638,6 @@ enum { STATE_SENT, /* Do not change state/UUIDs while this is set */ CALLBACK_PENDING, /* Whether we have a call_usermodehelper(, UMH_WAIT_PROC) * pending, from drbd worker context. - * If set, bdi_write_congested() returns true, - * so shrink_page_list() would not recurse into, - * and potentially deadlock on, this drbd worker. */ DISCONNECT_SENT, diff --git a/drivers/block/drbd/drbd_req.c b/drivers/block/drbd/drbd_req.c index 3235532ae077..2e5fb7e442e3 100644 --- a/drivers/block/drbd/drbd_req.c +++ b/drivers/block/drbd/drbd_req.c @@ -909,8 +909,7 @@ static bool remote_due_to_read_balancing(struct drbd_device *device, sector_t se switch (rbm) { case RB_CONGESTED_REMOTE: - return bdi_read_congested( - device->ldev->backing_bdev->bd_disk->bdi); + return 0; case RB_LEAST_PENDING: return atomic_read(&device->local_cnt) > atomic_read(&device->ap_pending_cnt) + atomic_read(&device->rs_pending_cnt); diff --git a/fs/ext2/ialloc.c b/fs/ext2/ialloc.c index df14e750e9fe..998dd2ac8008 100644 --- a/fs/ext2/ialloc.c +++ b/fs/ext2/ialloc.c @@ -170,11 +170,6 @@ static void ext2_preread_inode(struct inode *inode) unsigned long offset; unsigned long block; struct ext2_group_desc * gdp; - struct backing_dev_info *bdi; - - bdi = inode_to_bdi(inode); - if (bdi_rw_congested(bdi)) - return; block_group = (inode->i_ino - 1) / EXT2_INODES_PER_GROUP(inode->i_sb); gdp = ext2_get_group_desc(inode->i_sb, block_group, NULL); diff --git a/fs/nilfs2/segbuf.c b/fs/nilfs2/segbuf.c index 43287b0d3e9b..f4b57bc0c586 100644 --- a/fs/nilfs2/segbuf.c +++ b/fs/nilfs2/segbuf.c @@ -341,18 +341,6 @@ static int nilfs_segbuf_submit_bio(struct nilfs_segment_buffer *segbuf, int mode_flags) { struct bio *bio = wi->bio; - int err; - - if (segbuf->sb_nbio > 0 && - bdi_write_congested(segbuf->sb_super->s_bdi)) { - wait_for_completion(&segbuf->sb_bio_event); - segbuf->sb_nbio--; - if (unlikely(atomic_read(&segbuf->sb_err))) { - bio_put(bio); - err = -EIO; - goto failed; - } - } bio->bi_end_io = nilfs_end_bio_write; bio->bi_private = segbuf; @@ -365,10 +353,6 @@ static int nilfs_segbuf_submit_bio(struct nilfs_segment_buffer *segbuf, wi->nr_vecs = min(wi->max_pages, wi->rest_blocks); wi->start = wi->end; return 0; - - failed: - wi->bio = NULL; - return err; } /** diff --git a/fs/xfs/xfs_buf.c b/fs/xfs/xfs_buf.c index b45e0d50a405..b7ebcfe6b8d3 100644 --- a/fs/xfs/xfs_buf.c +++ b/fs/xfs/xfs_buf.c @@ -843,9 +843,6 @@ xfs_buf_readahead_map( { struct xfs_buf *bp; - if (bdi_read_congested(target->bt_bdev->bd_disk->bdi)) - return; - xfs_buf_read_map(target, map, nmaps, XBF_TRYLOCK | XBF_ASYNC | XBF_READ_AHEAD, &bp, ops, __this_address); diff --git a/include/linux/backing-dev.h b/include/linux/backing-dev.h index 860b675c2929..2d764566280c 100644 --- a/include/linux/backing-dev.h +++ b/include/linux/backing-dev.h @@ -135,11 +135,6 @@ static inline bool writeback_in_progress(struct bdi_writeback *wb) struct backing_dev_info *inode_to_bdi(struct inode *inode); -static inline int wb_congested(struct bdi_writeback *wb, int cong_bits) -{ - return wb->congested & cong_bits; -} - long congestion_wait(int sync, long timeout); static inline bool mapping_can_writeback(struct address_space *mapping) @@ -391,27 +386,6 @@ static inline void wb_blkcg_offline(struct blkcg *blkcg) #endif /* CONFIG_CGROUP_WRITEBACK */ -static inline int bdi_congested(struct backing_dev_info *bdi, int cong_bits) -{ - return wb_congested(&bdi->wb, cong_bits); -} - -static inline int bdi_read_congested(struct backing_dev_info *bdi) -{ - return bdi_congested(bdi, 1 << WB_sync_congested); -} - -static inline int bdi_write_congested(struct backing_dev_info *bdi) -{ - return bdi_congested(bdi, 1 << WB_async_congested); -} - -static inline int bdi_rw_congested(struct backing_dev_info *bdi) -{ - return bdi_congested(bdi, (1 << WB_sync_congested) | - (1 << WB_async_congested)); -} - const char *bdi_dev_name(struct backing_dev_info *bdi); #endif /* _LINUX_BACKING_DEV_H */ diff --git a/mm/vmscan.c b/mm/vmscan.c index e38de6456cdc..5e1469887afa 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -2364,9 +2364,7 @@ static unsigned int move_pages_to_lru(struct lruvec *lruvec, */ static int current_may_throttle(void) { - return !(current->flags & PF_LOCAL_THROTTLE) || - current->backing_dev_info == NULL || - bdi_write_congested(current->backing_dev_info); + return !(current->flags & PF_LOCAL_THROTTLE); } /* -- cgit v1.2.3 From a88f2096d5a2d91179db5dd9aa8f60dc3df9bb3e Mon Sep 17 00:00:00 2001 From: NeilBrown Date: Tue, 22 Mar 2022 14:39:19 -0700 Subject: remove congestion tracking framework This framework is no longer used - so discard it. Link: https://lkml.kernel.org/r/164549983747.9187.6171768583526866601.stgit@noble.brown Signed-off-by: NeilBrown Cc: Anna Schumaker Cc: Chao Yu Cc: Darrick J. Wong Cc: Ilya Dryomov Cc: Jaegeuk Kim Cc: Jan Kara Cc: Jeff Layton Cc: Jens Axboe Cc: Lars Ellenberg Cc: Miklos Szeredi Cc: Paolo Valente Cc: Philipp Reisner Cc: Ryusuke Konishi Cc: Trond Myklebust Cc: Wu Fengguang Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/backing-dev-defs.h | 8 ------ include/linux/backing-dev.h | 2 -- include/trace/events/writeback.h | 28 -------------------- mm/backing-dev.c | 57 ---------------------------------------- 4 files changed, 95 deletions(-) (limited to 'include/linux') diff --git a/include/linux/backing-dev-defs.h b/include/linux/backing-dev-defs.h index 993c5628a726..e863c88df95f 100644 --- a/include/linux/backing-dev-defs.h +++ b/include/linux/backing-dev-defs.h @@ -207,14 +207,6 @@ struct backing_dev_info { #endif }; -enum { - BLK_RW_ASYNC = 0, - BLK_RW_SYNC = 1, -}; - -void clear_bdi_congested(struct backing_dev_info *bdi, int sync); -void set_bdi_congested(struct backing_dev_info *bdi, int sync); - struct wb_lock_cookie { bool locked; unsigned long flags; diff --git a/include/linux/backing-dev.h b/include/linux/backing-dev.h index 2d764566280c..87ce24d238f3 100644 --- a/include/linux/backing-dev.h +++ b/include/linux/backing-dev.h @@ -135,8 +135,6 @@ static inline bool writeback_in_progress(struct bdi_writeback *wb) struct backing_dev_info *inode_to_bdi(struct inode *inode); -long congestion_wait(int sync, long timeout); - static inline bool mapping_can_writeback(struct address_space *mapping) { return inode_to_bdi(mapping->host)->capabilities & BDI_CAP_WRITEBACK; diff --git a/include/trace/events/writeback.h b/include/trace/events/writeback.h index a345b1e12daf..86b2a82da546 100644 --- a/include/trace/events/writeback.h +++ b/include/trace/events/writeback.h @@ -735,34 +735,6 @@ TRACE_EVENT(writeback_sb_inodes_requeue, ) ); -DECLARE_EVENT_CLASS(writeback_congest_waited_template, - - TP_PROTO(unsigned int usec_timeout, unsigned int usec_delayed), - - TP_ARGS(usec_timeout, usec_delayed), - - TP_STRUCT__entry( - __field( unsigned int, usec_timeout ) - __field( unsigned int, usec_delayed ) - ), - - TP_fast_assign( - __entry->usec_timeout = usec_timeout; - __entry->usec_delayed = usec_delayed; - ), - - TP_printk("usec_timeout=%u usec_delayed=%u", - __entry->usec_timeout, - __entry->usec_delayed) -); - -DEFINE_EVENT(writeback_congest_waited_template, writeback_congestion_wait, - - TP_PROTO(unsigned int usec_timeout, unsigned int usec_delayed), - - TP_ARGS(usec_timeout, usec_delayed) -); - DECLARE_EVENT_CLASS(writeback_single_inode_template, TP_PROTO(struct inode *inode, diff --git a/mm/backing-dev.c b/mm/backing-dev.c index eae96dfe0261..7176af65b103 100644 --- a/mm/backing-dev.c +++ b/mm/backing-dev.c @@ -1005,60 +1005,3 @@ const char *bdi_dev_name(struct backing_dev_info *bdi) return bdi->dev_name; } EXPORT_SYMBOL_GPL(bdi_dev_name); - -static wait_queue_head_t congestion_wqh[2] = { - __WAIT_QUEUE_HEAD_INITIALIZER(congestion_wqh[0]), - __WAIT_QUEUE_HEAD_INITIALIZER(congestion_wqh[1]) - }; -static atomic_t nr_wb_congested[2]; - -void clear_bdi_congested(struct backing_dev_info *bdi, int sync) -{ - wait_queue_head_t *wqh = &congestion_wqh[sync]; - enum wb_congested_state bit; - - bit = sync ? WB_sync_congested : WB_async_congested; - if (test_and_clear_bit(bit, &bdi->wb.congested)) - atomic_dec(&nr_wb_congested[sync]); - smp_mb__after_atomic(); - if (waitqueue_active(wqh)) - wake_up(wqh); -} -EXPORT_SYMBOL(clear_bdi_congested); - -void set_bdi_congested(struct backing_dev_info *bdi, int sync) -{ - enum wb_congested_state bit; - - bit = sync ? WB_sync_congested : WB_async_congested; - if (!test_and_set_bit(bit, &bdi->wb.congested)) - atomic_inc(&nr_wb_congested[sync]); -} -EXPORT_SYMBOL(set_bdi_congested); - -/** - * congestion_wait - wait for a backing_dev to become uncongested - * @sync: SYNC or ASYNC IO - * @timeout: timeout in jiffies - * - * Waits for up to @timeout jiffies for a backing_dev (any backing_dev) to exit - * write congestion. If no backing_devs are congested then just wait for the - * next write to be completed. - */ -long congestion_wait(int sync, long timeout) -{ - long ret; - unsigned long start = jiffies; - DEFINE_WAIT(wait); - wait_queue_head_t *wqh = &congestion_wqh[sync]; - - prepare_to_wait(wqh, &wait, TASK_UNINTERRUPTIBLE); - ret = io_schedule_timeout(timeout); - finish_wait(wqh, &wait); - - trace_writeback_congestion_wait(jiffies_to_usecs(timeout), - jiffies_to_usecs(jiffies - start)); - - return ret; -} -EXPORT_SYMBOL(congestion_wait); -- cgit v1.2.3 From a128b054ce029554a4a52fc3abb8c1df8bafcaef Mon Sep 17 00:00:00 2001 From: Anthony Iliopoulos Date: Tue, 22 Mar 2022 14:39:22 -0700 Subject: mount: warn only once about timestamp range expiration Commit f8b92ba67c5d ("mount: Add mount warning for impending timestamp expiry") introduced a mount warning regarding filesystem timestamp limits, that is printed upon each writable mount or remount. This can result in a lot of unnecessary messages in the kernel log in setups where filesystems are being frequently remounted (or mounted multiple times). Avoid this by setting a superblock flag which indicates that the warning has been emitted at least once for any particular mount, as suggested in [1]. Link: https://lore.kernel.org/CAHk-=wim6VGnxQmjfK_tDg6fbHYKL4EFkmnTjVr9QnRqjDBAeA@mail.gmail.com/ [1] Link: https://lkml.kernel.org/r/20220119202934.26495-1-ailiop@suse.com Signed-off-by: Anthony Iliopoulos Reviewed-by: Christoph Hellwig Acked-by: Christian Brauner Reviewed-by: Darrick J. Wong Cc: Alexander Viro Cc: Deepa Dinamani Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/namespace.c | 2 ++ include/linux/fs.h | 1 + 2 files changed, 3 insertions(+) (limited to 'include/linux') diff --git a/fs/namespace.c b/fs/namespace.c index de6fae84f1a1..0044feef59d0 100644 --- a/fs/namespace.c +++ b/fs/namespace.c @@ -2597,6 +2597,7 @@ static void mnt_warn_timestamp_expiry(struct path *mountpoint, struct vfsmount * struct super_block *sb = mnt->mnt_sb; if (!__mnt_is_readonly(mnt) && + (!(sb->s_iflags & SB_I_TS_EXPIRY_WARNED)) && (ktime_get_real_seconds() + TIME_UPTIME_SEC_MAX > sb->s_time_max)) { char *buf = (char *)__get_free_page(GFP_KERNEL); char *mntpath = buf ? d_path(mountpoint, buf, PAGE_SIZE) : ERR_PTR(-ENOMEM); @@ -2611,6 +2612,7 @@ static void mnt_warn_timestamp_expiry(struct path *mountpoint, struct vfsmount * tm.tm_year+1900, (unsigned long long)sb->s_time_max); free_page((unsigned long)buf); + sb->s_iflags |= SB_I_TS_EXPIRY_WARNED; } } diff --git a/include/linux/fs.h b/include/linux/fs.h index 8b5c486bd4a2..ca9445f6cf3d 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -1440,6 +1440,7 @@ extern int send_sigurg(struct fown_struct *fown); #define SB_I_SKIP_SYNC 0x00000100 /* Skip superblock at global sync */ #define SB_I_PERSB_BDI 0x00000200 /* has a per-sb bdi */ +#define SB_I_TS_EXPIRY_WARNED 0x00000400 /* warned about timestamp range expiry */ /* Possible states of 'frozen' field */ enum { -- cgit v1.2.3 From eb5279fb7e41804ecc15ed3cf716a9e2b419af57 Mon Sep 17 00:00:00 2001 From: Miaohe Lin Date: Tue, 22 Mar 2022 14:39:28 -0700 Subject: filemap: remove find_get_pages() It's unused now. Remove it and clean up the relevant comment. Link: https://lkml.kernel.org/r/20220208134149.47299-1-linmiaohe@huawei.com Signed-off-by: Miaohe Lin Reviewed-by: Christoph Hellwig Cc: Matthew Wilcox (Oracle) Cc: David Howells Cc: William Kucharski Cc: Vlastimil Babka Cc: Kirill A. Shutemov Cc: Johannes Weiner Cc: Andreas Gruenbacher Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/pagemap.h | 7 ------- mm/filemap.c | 11 ++++++----- 2 files changed, 6 insertions(+), 12 deletions(-) (limited to 'include/linux') diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h index 270bf5136c34..dc31eb981ea2 100644 --- a/include/linux/pagemap.h +++ b/include/linux/pagemap.h @@ -594,13 +594,6 @@ static inline struct page *find_subpage(struct page *head, pgoff_t index) unsigned find_get_pages_range(struct address_space *mapping, pgoff_t *start, pgoff_t end, unsigned int nr_pages, struct page **pages); -static inline unsigned find_get_pages(struct address_space *mapping, - pgoff_t *start, unsigned int nr_pages, - struct page **pages) -{ - return find_get_pages_range(mapping, start, (pgoff_t)-1, nr_pages, - pages); -} unsigned find_get_pages_contig(struct address_space *mapping, pgoff_t start, unsigned int nr_pages, struct page **pages); unsigned find_get_pages_range_tag(struct address_space *mapping, pgoff_t *index, diff --git a/mm/filemap.c b/mm/filemap.c index ad8c39d90bf9..90afe301cd52 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -2229,8 +2229,9 @@ out: * @nr_pages: The maximum number of pages * @pages: Where the resulting pages are placed * - * find_get_pages_contig() works exactly like find_get_pages(), except - * that the returned number of pages are guaranteed to be contiguous. + * find_get_pages_contig() works exactly like find_get_pages_range(), + * except that the returned number of pages are guaranteed to be + * contiguous. * * Return: the number of pages which were found. */ @@ -2290,9 +2291,9 @@ EXPORT_SYMBOL(find_get_pages_contig); * @nr_pages: the maximum number of pages * @pages: where the resulting pages are placed * - * Like find_get_pages(), except we only return head pages which are tagged - * with @tag. @index is updated to the index immediately after the last - * page we return, ready for the next iteration. + * Like find_get_pages_range(), except we only return head pages which are + * tagged with @tag. @index is updated to the index immediately after the + * last page we return, ready for the next iteration. * * Return: the number of pages which were found. */ -- cgit v1.2.3 From ad6c441266dcd50be080a47e1178a1b15369923c Mon Sep 17 00:00:00 2001 From: John Hubbard Date: Tue, 22 Mar 2022 14:39:43 -0700 Subject: mm/gup: remove unused pin_user_pages_locked() This routine was used for a short while, but then the calling code was refactored and the only caller was removed. Link: https://lkml.kernel.org/r/20220204020010.68930-4-jhubbard@nvidia.com Signed-off-by: John Hubbard Reviewed-by: David Hildenbrand Reviewed-by: Jason Gunthorpe Reviewed-by: Jan Kara Reviewed-by: Christoph Hellwig Reviewed-by: Claudio Imbrenda Cc: Alex Williamson Cc: Andrea Arcangeli Cc: Jason Gunthorpe Cc: Kirill A. Shutemov Cc: Lukas Bulwahn Cc: Matthew Wilcox (Oracle) Cc: Peter Xu Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/mm.h | 2 -- mm/gup.c | 29 ----------------------------- 2 files changed, 31 deletions(-) (limited to 'include/linux') diff --git a/include/linux/mm.h b/include/linux/mm.h index 5744a3fc4716..d4a2b40066fa 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -1918,8 +1918,6 @@ long pin_user_pages(unsigned long start, unsigned long nr_pages, struct vm_area_struct **vmas); long get_user_pages_locked(unsigned long start, unsigned long nr_pages, unsigned int gup_flags, struct page **pages, int *locked); -long pin_user_pages_locked(unsigned long start, unsigned long nr_pages, - unsigned int gup_flags, struct page **pages, int *locked); long get_user_pages_unlocked(unsigned long start, unsigned long nr_pages, struct page **pages, unsigned int gup_flags); long pin_user_pages_unlocked(unsigned long start, unsigned long nr_pages, diff --git a/mm/gup.c b/mm/gup.c index 43ad2bc6ca51..f8faa646f208 100644 --- a/mm/gup.c +++ b/mm/gup.c @@ -3127,32 +3127,3 @@ long pin_user_pages_unlocked(unsigned long start, unsigned long nr_pages, return get_user_pages_unlocked(start, nr_pages, pages, gup_flags); } EXPORT_SYMBOL(pin_user_pages_unlocked); - -/* - * pin_user_pages_locked() is the FOLL_PIN variant of get_user_pages_locked(). - * Behavior is the same, except that this one sets FOLL_PIN and rejects - * FOLL_GET. - */ -long pin_user_pages_locked(unsigned long start, unsigned long nr_pages, - unsigned int gup_flags, struct page **pages, - int *locked) -{ - /* - * FIXME: Current FOLL_LONGTERM behavior is incompatible with - * FAULT_FLAG_ALLOW_RETRY because of the FS DAX check requirement on - * vmas. As there are no users of this flag in this call we simply - * disallow this option for now. - */ - if (WARN_ON_ONCE(gup_flags & FOLL_LONGTERM)) - return -EINVAL; - - /* FOLL_GET and FOLL_PIN are mutually exclusive. */ - if (WARN_ON_ONCE(gup_flags & FOLL_GET)) - return -EINVAL; - - gup_flags |= FOLL_PIN; - return __get_user_pages_locked(current->mm, start, nr_pages, - pages, NULL, locked, - gup_flags | FOLL_TOUCH); -} -EXPORT_SYMBOL(pin_user_pages_locked); -- cgit v1.2.3 From 73fd16d8080f7b1537ba7aa29917f64d6fffa664 Mon Sep 17 00:00:00 2001 From: John Hubbard Date: Tue, 22 Mar 2022 14:39:50 -0700 Subject: mm/gup: remove unused get_user_pages_locked() Now that the last caller of get_user_pages_locked() is gone, remove it. Link: https://lkml.kernel.org/r/20220204020010.68930-6-jhubbard@nvidia.com Signed-off-by: John Hubbard Reviewed-by: Jan Kara Reviewed-by: Jason Gunthorpe Reviewed-by: Claudio Imbrenda Reviewed-by: Christoph Hellwig Cc: Alex Williamson Cc: Andrea Arcangeli Cc: David Hildenbrand Cc: Jason Gunthorpe Cc: Kirill A. Shutemov Cc: Lukas Bulwahn Cc: Matthew Wilcox (Oracle) Cc: Peter Xu Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/mm.h | 2 -- mm/gup.c | 59 ------------------------------------------------------ 2 files changed, 61 deletions(-) (limited to 'include/linux') diff --git a/include/linux/mm.h b/include/linux/mm.h index d4a2b40066fa..c02a8cc16e4f 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -1916,8 +1916,6 @@ long get_user_pages(unsigned long start, unsigned long nr_pages, long pin_user_pages(unsigned long start, unsigned long nr_pages, unsigned int gup_flags, struct page **pages, struct vm_area_struct **vmas); -long get_user_pages_locked(unsigned long start, unsigned long nr_pages, - unsigned int gup_flags, struct page **pages, int *locked); long get_user_pages_unlocked(unsigned long start, unsigned long nr_pages, struct page **pages, unsigned int gup_flags); long pin_user_pages_unlocked(unsigned long start, unsigned long nr_pages, diff --git a/mm/gup.c b/mm/gup.c index f8faa646f208..85d59dc08644 100644 --- a/mm/gup.c +++ b/mm/gup.c @@ -2126,65 +2126,6 @@ long get_user_pages(unsigned long start, unsigned long nr_pages, } EXPORT_SYMBOL(get_user_pages); -/** - * get_user_pages_locked() - variant of get_user_pages() - * - * @start: starting user address - * @nr_pages: number of pages from start to pin - * @gup_flags: flags modifying lookup behaviour - * @pages: array that receives pointers to the pages pinned. - * Should be at least nr_pages long. Or NULL, if caller - * only intends to ensure the pages are faulted in. - * @locked: pointer to lock flag indicating whether lock is held and - * subsequently whether VM_FAULT_RETRY functionality can be - * utilised. Lock must initially be held. - * - * It is suitable to replace the form: - * - * mmap_read_lock(mm); - * do_something() - * get_user_pages(mm, ..., pages, NULL); - * mmap_read_unlock(mm); - * - * to: - * - * int locked = 1; - * mmap_read_lock(mm); - * do_something() - * get_user_pages_locked(mm, ..., pages, &locked); - * if (locked) - * mmap_read_unlock(mm); - * - * We can leverage the VM_FAULT_RETRY functionality in the page fault - * paths better by using either get_user_pages_locked() or - * get_user_pages_unlocked(). - * - */ -long get_user_pages_locked(unsigned long start, unsigned long nr_pages, - unsigned int gup_flags, struct page **pages, - int *locked) -{ - /* - * FIXME: Current FOLL_LONGTERM behavior is incompatible with - * FAULT_FLAG_ALLOW_RETRY because of the FS DAX check requirement on - * vmas. As there are no users of this flag in this call we simply - * disallow this option for now. - */ - if (WARN_ON_ONCE(gup_flags & FOLL_LONGTERM)) - return -EINVAL; - /* - * FOLL_PIN must only be set internally by the pin_user_pages*() APIs, - * never directly by the caller, so enforce that: - */ - if (WARN_ON_ONCE(gup_flags & FOLL_PIN)) - return -EINVAL; - - return __get_user_pages_locked(current->mm, start, nr_pages, - pages, NULL, locked, - gup_flags | FOLL_TOUCH); -} -EXPORT_SYMBOL(get_user_pages_locked); - /* * get_user_pages_unlocked() is suitable to replace the form: * -- cgit v1.2.3 From f7cd16a55837f37b4c3835a2c646023e4d0f0e04 Mon Sep 17 00:00:00 2001 From: Xavier Roche Date: Tue, 22 Mar 2022 14:39:55 -0700 Subject: tmpfs: support for file creation time Various filesystems (including ext4) now support file creation time. This adds such support for tmpfs-based filesystems. Note that using shmem_getattr() on other file types than regular requires that shmem_is_huge() check type, to stop incorrect HPAGE_PMD_SIZE blksize. [hughd@google.com: three tweaks to creation time patch] Link: https://lkml.kernel.org/r/b954973a-b8d1-cab8-63bd-6ea8063de3@google.com Link: https://lkml.kernel.org/r/20220314211150.GA123458@xavier-xps Link: https://lkml.kernel.org/r/b954973a-b8d1-cab8-63bd-6ea8063de3@google.com Link: https://lkml.kernel.org/r/20220211213628.GA1919658@xavier-xps Signed-off-by: Xavier Roche Signed-off-by: Hugh Dickins Tested-by: Jean Delvare Tested-by: Sylvain Bellone Reported-by: Xavier Grand Reviewed-by: Jean Delvare Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/shmem_fs.h | 1 + mm/shmem.c | 16 +++++++++++++--- 2 files changed, 14 insertions(+), 3 deletions(-) (limited to 'include/linux') diff --git a/include/linux/shmem_fs.h b/include/linux/shmem_fs.h index e65b80ed09e7..ab51d3cd39bd 100644 --- a/include/linux/shmem_fs.h +++ b/include/linux/shmem_fs.h @@ -24,6 +24,7 @@ struct shmem_inode_info { struct shared_policy policy; /* NUMA memory alloc policy */ struct simple_xattrs xattrs; /* list of xattrs */ atomic_t stop_eviction; /* hold when working on inode */ + struct timespec64 i_crtime; /* file creation time */ struct inode vfs_inode; }; diff --git a/mm/shmem.c b/mm/shmem.c index a09b29ec2b45..f8205b2b0322 100644 --- a/mm/shmem.c +++ b/mm/shmem.c @@ -476,6 +476,8 @@ bool shmem_is_huge(struct vm_area_struct *vma, { loff_t i_size; + if (!S_ISREG(inode->i_mode)) + return false; if (shmem_huge == SHMEM_HUGE_DENY) return false; if (vma && ((vma->vm_flags & VM_NOHUGEPAGE) || @@ -1061,6 +1063,12 @@ static int shmem_getattr(struct user_namespace *mnt_userns, if (shmem_is_huge(NULL, inode, 0)) stat->blksize = HPAGE_PMD_SIZE; + if (request_mask & STATX_BTIME) { + stat->result_mask |= STATX_BTIME; + stat->btime.tv_sec = info->i_crtime.tv_sec; + stat->btime.tv_nsec = info->i_crtime.tv_nsec; + } + return 0; } @@ -1854,9 +1862,6 @@ repeat: return 0; } - /* Never use a huge page for shmem_symlink() */ - if (S_ISLNK(inode->i_mode)) - goto alloc_nohuge; if (!shmem_is_huge(vma, inode, index)) goto alloc_nohuge; @@ -2265,6 +2270,7 @@ static struct inode *shmem_get_inode(struct super_block *sb, const struct inode atomic_set(&info->stop_eviction, 0); info->seals = F_SEAL_SEAL; info->flags = flags & VM_NORESERVE; + info->i_crtime = inode->i_mtime; INIT_LIST_HEAD(&info->shrinklist); INIT_LIST_HEAD(&info->swaplist); simple_xattrs_init(&info->xattrs); @@ -3196,6 +3202,7 @@ static ssize_t shmem_listxattr(struct dentry *dentry, char *buffer, size_t size) #endif /* CONFIG_TMPFS_XATTR */ static const struct inode_operations shmem_short_symlink_operations = { + .getattr = shmem_getattr, .get_link = simple_get_link, #ifdef CONFIG_TMPFS_XATTR .listxattr = shmem_listxattr, @@ -3203,6 +3210,7 @@ static const struct inode_operations shmem_short_symlink_operations = { }; static const struct inode_operations shmem_symlink_inode_operations = { + .getattr = shmem_getattr, .get_link = shmem_get_link, #ifdef CONFIG_TMPFS_XATTR .listxattr = shmem_listxattr, @@ -3790,6 +3798,7 @@ static const struct inode_operations shmem_inode_operations = { static const struct inode_operations shmem_dir_inode_operations = { #ifdef CONFIG_TMPFS + .getattr = shmem_getattr, .create = shmem_create, .lookup = simple_lookup, .link = shmem_link, @@ -3811,6 +3820,7 @@ static const struct inode_operations shmem_dir_inode_operations = { }; static const struct inode_operations shmem_special_inode_operations = { + .getattr = shmem_getattr, #ifdef CONFIG_TMPFS_XATTR .listxattr = shmem_listxattr, #endif -- cgit v1.2.3 From a8c49af3be5f0b4e105ef678bcf14ef102c270be Mon Sep 17 00:00:00 2001 From: Yosry Ahmed Date: Tue, 22 Mar 2022 14:40:10 -0700 Subject: memcg: add per-memcg total kernel memory stat Currently memcg stats show several types of kernel memory: kernel stack, page tables, sock, vmalloc, and slab. However, there are other allocations with __GFP_ACCOUNT (or supersets such as GFP_KERNEL_ACCOUNT) that are not accounted in any of those stats, a few examples are: - various kvm allocations (e.g. allocated pages to create vcpus) - io_uring - tmp_page in pipes during pipe_write() - bpf ringbuffers - unix sockets Keeping track of the total kernel memory is essential for the ease of migration from cgroup v1 to v2 as there are large discrepancies between v1's kmem.usage_in_bytes and the sum of the available kernel memory stats in v2. Adding separate memcg stats for all __GFP_ACCOUNT kernel allocations is an impractical maintenance burden as there a lot of those all over the kernel code, with more use cases likely to show up in the future. Therefore, add a "kernel" memcg stat that is analogous to kmem page counter, with added benefits such as using rstat infrastructure which aggregates stats more efficiently. Additionally, this provides a lighter alternative in case the legacy kmem is deprecated in the future [yosryahmed@google.com: v2] Link: https://lkml.kernel.org/r/20220203193856.972500-1-yosryahmed@google.com Link: https://lkml.kernel.org/r/20220201200823.3283171-1-yosryahmed@google.com Signed-off-by: Yosry Ahmed Acked-by: Shakeel Butt Acked-by: Johannes Weiner Cc: Michal Hocko Cc: Muchun Song Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- Documentation/admin-guide/cgroup-v2.rst | 5 +++++ include/linux/memcontrol.h | 1 + mm/memcontrol.c | 27 +++++++++++++++++++++------ 3 files changed, 27 insertions(+), 6 deletions(-) (limited to 'include/linux') diff --git a/Documentation/admin-guide/cgroup-v2.rst b/Documentation/admin-guide/cgroup-v2.rst index 5aa368d165da..69d7a6983f78 100644 --- a/Documentation/admin-guide/cgroup-v2.rst +++ b/Documentation/admin-guide/cgroup-v2.rst @@ -1301,6 +1301,11 @@ PAGE_SIZE multiple when read back. Amount of memory used to cache filesystem data, including tmpfs and shared memory. + kernel (npn) + Amount of total kernel memory, including + (kernel_stack, pagetables, percpu, vmalloc, slab) in + addition to other kernel memory use cases. + kernel_stack Amount of memory allocated to kernel stacks. diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h index 0abbd685703b..8612d7dd0859 100644 --- a/include/linux/memcontrol.h +++ b/include/linux/memcontrol.h @@ -34,6 +34,7 @@ enum memcg_stat_item { MEMCG_SOCK, MEMCG_PERCPU_B, MEMCG_VMALLOC, + MEMCG_KMEM, MEMCG_NR_STAT, }; diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 209e66893da6..e64a276837b0 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -1371,6 +1371,7 @@ struct memory_stat { static const struct memory_stat memory_stats[] = { { "anon", NR_ANON_MAPPED }, { "file", NR_FILE_PAGES }, + { "kernel", MEMCG_KMEM }, { "kernel_stack", NR_KERNEL_STACK_KB }, { "pagetables", NR_PAGETABLE }, { "percpu", MEMCG_PERCPU_B }, @@ -2114,6 +2115,7 @@ static DEFINE_MUTEX(percpu_charge_mutex); static void drain_obj_stock(struct obj_stock *stock); static bool obj_stock_flush_required(struct memcg_stock_pcp *stock, struct mem_cgroup *root_memcg); +static void memcg_account_kmem(struct mem_cgroup *memcg, int nr_pages); #else static inline void drain_obj_stock(struct obj_stock *stock) @@ -2124,6 +2126,9 @@ static bool obj_stock_flush_required(struct memcg_stock_pcp *stock, { return false; } +static void memcg_account_kmem(struct mem_cgroup *memcg, int nr_pages) +{ +} #endif /** @@ -2979,6 +2984,18 @@ static void memcg_free_cache_id(int id) ida_simple_remove(&memcg_cache_ida, id); } +static void memcg_account_kmem(struct mem_cgroup *memcg, int nr_pages) +{ + mod_memcg_state(memcg, MEMCG_KMEM, nr_pages); + if (!cgroup_subsys_on_dfl(memory_cgrp_subsys)) { + if (nr_pages > 0) + page_counter_charge(&memcg->kmem, nr_pages); + else + page_counter_uncharge(&memcg->kmem, -nr_pages); + } +} + + /* * obj_cgroup_uncharge_pages: uncharge a number of kernel pages from a objcg * @objcg: object cgroup to uncharge @@ -2991,8 +3008,7 @@ static void obj_cgroup_uncharge_pages(struct obj_cgroup *objcg, memcg = get_mem_cgroup_from_objcg(objcg); - if (!cgroup_subsys_on_dfl(memory_cgrp_subsys)) - page_counter_uncharge(&memcg->kmem, nr_pages); + memcg_account_kmem(memcg, -nr_pages); refill_stock(memcg, nr_pages); css_put(&memcg->css); @@ -3018,8 +3034,7 @@ static int obj_cgroup_charge_pages(struct obj_cgroup *objcg, gfp_t gfp, if (ret) goto out; - if (!cgroup_subsys_on_dfl(memory_cgrp_subsys)) - page_counter_charge(&memcg->kmem, nr_pages); + memcg_account_kmem(memcg, nr_pages); out: css_put(&memcg->css); @@ -6801,8 +6816,8 @@ static void uncharge_batch(const struct uncharge_gather *ug) page_counter_uncharge(&ug->memcg->memory, ug->nr_memory); if (do_memsw_account()) page_counter_uncharge(&ug->memcg->memsw, ug->nr_memory); - if (!cgroup_subsys_on_dfl(memory_cgrp_subsys) && ug->nr_kmem) - page_counter_uncharge(&ug->memcg->kmem, ug->nr_kmem); + if (ug->nr_kmem) + memcg_account_kmem(ug->memcg, -ug->nr_kmem); memcg_oom_recover(ug->memcg); } -- cgit v1.2.3 From 486bc7060cb510fa60cb85a013d5ed51ce0fe456 Mon Sep 17 00:00:00 2001 From: Wei Yang Date: Tue, 22 Mar 2022 14:40:16 -0700 Subject: mm/memcg: retrieve parent memcg from css.parent The parent we get from page_counter is correct, while this is two different hierarchy. Let's retrieve the parent memcg from css.parent just like parent_cs(), blkcg_parent(), etc. Link: https://lkml.kernel.org/r/20220201004643.8391-2-richard.weiyang@gmail.com Signed-off-by: Wei Yang Reviewed-by: Muchun Song Acked-by: Michal Hocko Reviewed-by: Roman Gushchin Reviewed-by: Shakeel Butt Cc: Roman Gushchin Cc: Johannes Weiner Cc: Vladimir Davydov Cc: Yang Shi Cc: Suren Baghdasaryan Cc: Vlastimil Babka Cc: Mike Rapoport Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/memcontrol.h | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) (limited to 'include/linux') diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h index 8612d7dd0859..ef4b445392a9 100644 --- a/include/linux/memcontrol.h +++ b/include/linux/memcontrol.h @@ -842,9 +842,7 @@ static inline struct mem_cgroup *lruvec_memcg(struct lruvec *lruvec) */ static inline struct mem_cgroup *parent_mem_cgroup(struct mem_cgroup *memcg) { - if (!memcg->memory.parent) - return NULL; - return mem_cgroup_from_counter(memcg->memory.parent, memory); + return mem_cgroup_from_css(memcg->css.parent); } static inline bool mem_cgroup_is_descendant(struct mem_cgroup *memcg, -- cgit v1.2.3 From 6a6b7b77cc0fdc13f50c66c219c8c05500a8dfce Mon Sep 17 00:00:00 2001 From: Muchun Song Date: Tue, 22 Mar 2022 14:40:53 -0700 Subject: mm: list_lru: transpose the array of per-node per-memcg lru lists Patch series "Optimize list lru memory consumption", v6. In our server, we found a suspected memory leak problem. The kmalloc-32 consumes more than 6GB of memory. Other kmem_caches consume less than 2GB memory. After our in-depth analysis, the memory consumption of kmalloc-32 slab cache is the cause of list_lru_one allocation. crash> p memcg_nr_cache_ids memcg_nr_cache_ids = $2 = 24574 memcg_nr_cache_ids is very large and memory consumption of each list_lru can be calculated with the following formula. num_numa_node * memcg_nr_cache_ids * 32 (kmalloc-32) There are 4 numa nodes in our system, so each list_lru consumes ~3MB. crash> list super_blocks | wc -l 952 Every mount will register 2 list lrus, one is for inode, another is for dentry. There are 952 super_blocks. So the total memory is 952 * 2 * 3 MB (~5.6GB). But now the number of memory cgroups is less than 500. So I guess more than 12286 memory cgroups have been created on this machine (I do not know why there are so many cgroups, it may be a user's bug or the user really want to do that). Because memcg_nr_cache_ids has not been reduced to a suitable value. It leads to waste a lot of memory. If we want to reduce memcg_nr_cache_ids, we have to *reboot* the server. This is not what we want. In order to reduce memcg_nr_cache_ids, I had posted a patchset [1] to do this. But this did not fundamentally solve the problem. We currently allocate scope for every memcg to be able to tracked on every superblock instantiated in the system, regardless of whether that superblock is even accessible to that memcg. These huge memcg counts come from container hosts where memcgs are confined to just a small subset of the total number of superblocks that instantiated at any given point in time. For these systems with huge container counts, list_lru does not need the capability of tracking every memcg on every superblock. What it comes down to is that the list_lru is only needed for a given memcg if that memcg is instatiating and freeing objects on a given list_lru. As Dave said, "Which makes me think we should be moving more towards 'add the memcg to the list_lru at the first insert' model rather than 'instantiate all at memcg init time just in case'." This patchset aims to optimize the list lru memory consumption from different aspects. I had done a easy test to show the optimization. I create 10k memory cgroups and mount 10k filesystems in the systems. We use free command to show how many memory does the systems comsumes after this operation (There are 2 numa nodes in the system). +-----------------------+------------------------+ | condition | memory consumption | +-----------------------+------------------------+ | without this patchset | 24464 MB | +-----------------------+------------------------+ | after patch 1 | 21957 MB | <--------+ +-----------------------+------------------------+ | | after patch 10 | 6895 MB | | +-----------------------+------------------------+ | | after patch 12 | 4367 MB | | +-----------------------+------------------------+ | | The more the number of nodes, the more obvious the effect---+ BTW, there was a recent discussion [2] on the same issue. [1] https://lore.kernel.org/all/20210428094949.43579-1-songmuchun@bytedance.com/ [2] https://lore.kernel.org/all/20210405054848.GA1077931@in.ibm.com/ This series not only optimizes the memory usage of list_lru but also simplifies the code. This patch (of 16): The current scheme of maintaining per-node per-memcg lru lists looks like: struct list_lru { struct list_lru_node *node; (for each node) struct list_lru_memcg *memcg_lrus; struct list_lru_one *lru[]; (for each memcg) } By effectively transposing the two-dimension array of list_lru_one's structures (per-node per-memcg => per-memcg per-node) it's possible to save some memory and simplify alloc/dealloc paths. The new scheme looks like: struct list_lru { struct list_lru_memcg *mlrus; struct list_lru_per_memcg *mlru[]; (for each memcg) struct list_lru_one node[0]; (for each node) } Memory savings are coming from not only 'struct rcu_head' but also some pointer arrays used to store the pointer to 'struct list_lru_one'. The array is per node and its size is 8 (a pointer) * num_memcgs. So the total size of the arrays is 8 * num_nodes * memcg_nr_cache_ids. After this patch, the size becomes 8 * memcg_nr_cache_ids. Link: https://lkml.kernel.org/r/20220228122126.37293-1-songmuchun@bytedance.com Link: https://lkml.kernel.org/r/20220228122126.37293-2-songmuchun@bytedance.com Signed-off-by: Muchun Song Acked-by: Johannes Weiner Cc: Matthew Wilcox (Oracle) Cc: Michal Hocko Cc: Vladimir Davydov Cc: Shakeel Butt Cc: Yang Shi Cc: Alex Shi Cc: Wei Yang Cc: Dave Chinner Cc: Trond Myklebust Cc: Anna Schumaker Cc: Jaegeuk Kim Cc: Chao Yu Cc: Kari Argillander Cc: Vlastimil Babka Cc: Qi Zheng Cc: Xiongchun Duan Cc: Fam Zheng Cc: Roman Gushchin Cc: Theodore Ts'o Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/list_lru.h | 17 ++-- mm/list_lru.c | 206 +++++++++++++++++------------------------------ 2 files changed, 86 insertions(+), 137 deletions(-) (limited to 'include/linux') diff --git a/include/linux/list_lru.h b/include/linux/list_lru.h index 1b5fceb565df..729a27b6ff53 100644 --- a/include/linux/list_lru.h +++ b/include/linux/list_lru.h @@ -31,10 +31,15 @@ struct list_lru_one { long nr_items; }; +struct list_lru_per_memcg { + /* array of per cgroup per node lists, indexed by node id */ + struct list_lru_one node[0]; +}; + struct list_lru_memcg { - struct rcu_head rcu; + struct rcu_head rcu; /* array of per cgroup lists, indexed by memcg_cache_id */ - struct list_lru_one *lru[]; + struct list_lru_per_memcg *mlru[]; }; struct list_lru_node { @@ -42,11 +47,7 @@ struct list_lru_node { spinlock_t lock; /* global list, used for the root cgroup in cgroup aware lrus */ struct list_lru_one lru; -#ifdef CONFIG_MEMCG_KMEM - /* for cgroup aware lrus points to per cgroup lists, otherwise NULL */ - struct list_lru_memcg __rcu *memcg_lrus; -#endif - long nr_items; + long nr_items; } ____cacheline_aligned_in_smp; struct list_lru { @@ -55,6 +56,8 @@ struct list_lru { struct list_head list; int shrinker_id; bool memcg_aware; + /* for cgroup aware lrus points to per cgroup lists, otherwise NULL */ + struct list_lru_memcg __rcu *mlrus; #endif }; diff --git a/mm/list_lru.c b/mm/list_lru.c index 0cd5e89ca063..7d1356241aa8 100644 --- a/mm/list_lru.c +++ b/mm/list_lru.c @@ -49,35 +49,37 @@ static int lru_shrinker_id(struct list_lru *lru) } static inline struct list_lru_one * -list_lru_from_memcg_idx(struct list_lru_node *nlru, int idx) +list_lru_from_memcg_idx(struct list_lru *lru, int nid, int idx) { - struct list_lru_memcg *memcg_lrus; + struct list_lru_memcg *mlrus; + struct list_lru_node *nlru = &lru->node[nid]; + /* * Either lock or RCU protects the array of per cgroup lists - * from relocation (see memcg_update_list_lru_node). + * from relocation (see memcg_update_list_lru). */ - memcg_lrus = rcu_dereference_check(nlru->memcg_lrus, - lockdep_is_held(&nlru->lock)); - if (memcg_lrus && idx >= 0) - return memcg_lrus->lru[idx]; + mlrus = rcu_dereference_check(lru->mlrus, lockdep_is_held(&nlru->lock)); + if (mlrus && idx >= 0) + return &mlrus->mlru[idx]->node[nid]; return &nlru->lru; } static inline struct list_lru_one * -list_lru_from_kmem(struct list_lru_node *nlru, void *ptr, +list_lru_from_kmem(struct list_lru *lru, int nid, void *ptr, struct mem_cgroup **memcg_ptr) { + struct list_lru_node *nlru = &lru->node[nid]; struct list_lru_one *l = &nlru->lru; struct mem_cgroup *memcg = NULL; - if (!nlru->memcg_lrus) + if (!lru->mlrus) goto out; memcg = mem_cgroup_from_obj(ptr); if (!memcg) goto out; - l = list_lru_from_memcg_idx(nlru, memcg_cache_id(memcg)); + l = list_lru_from_memcg_idx(lru, nid, memcg_cache_id(memcg)); out: if (memcg_ptr) *memcg_ptr = memcg; @@ -103,18 +105,18 @@ static inline bool list_lru_memcg_aware(struct list_lru *lru) } static inline struct list_lru_one * -list_lru_from_memcg_idx(struct list_lru_node *nlru, int idx) +list_lru_from_memcg_idx(struct list_lru *lru, int nid, int idx) { - return &nlru->lru; + return &lru->node[nid].lru; } static inline struct list_lru_one * -list_lru_from_kmem(struct list_lru_node *nlru, void *ptr, +list_lru_from_kmem(struct list_lru *lru, int nid, void *ptr, struct mem_cgroup **memcg_ptr) { if (memcg_ptr) *memcg_ptr = NULL; - return &nlru->lru; + return &lru->node[nid].lru; } #endif /* CONFIG_MEMCG_KMEM */ @@ -127,7 +129,7 @@ bool list_lru_add(struct list_lru *lru, struct list_head *item) spin_lock(&nlru->lock); if (list_empty(item)) { - l = list_lru_from_kmem(nlru, item, &memcg); + l = list_lru_from_kmem(lru, nid, item, &memcg); list_add_tail(item, &l->list); /* Set shrinker bit if the first element was added */ if (!l->nr_items++) @@ -150,7 +152,7 @@ bool list_lru_del(struct list_lru *lru, struct list_head *item) spin_lock(&nlru->lock); if (!list_empty(item)) { - l = list_lru_from_kmem(nlru, item, NULL); + l = list_lru_from_kmem(lru, nid, item, NULL); list_del_init(item); l->nr_items--; nlru->nr_items--; @@ -180,12 +182,11 @@ EXPORT_SYMBOL_GPL(list_lru_isolate_move); unsigned long list_lru_count_one(struct list_lru *lru, int nid, struct mem_cgroup *memcg) { - struct list_lru_node *nlru = &lru->node[nid]; struct list_lru_one *l; long count; rcu_read_lock(); - l = list_lru_from_memcg_idx(nlru, memcg_cache_id(memcg)); + l = list_lru_from_memcg_idx(lru, nid, memcg_cache_id(memcg)); count = READ_ONCE(l->nr_items); rcu_read_unlock(); @@ -206,16 +207,16 @@ unsigned long list_lru_count_node(struct list_lru *lru, int nid) EXPORT_SYMBOL_GPL(list_lru_count_node); static unsigned long -__list_lru_walk_one(struct list_lru_node *nlru, int memcg_idx, +__list_lru_walk_one(struct list_lru *lru, int nid, int memcg_idx, list_lru_walk_cb isolate, void *cb_arg, unsigned long *nr_to_walk) { - + struct list_lru_node *nlru = &lru->node[nid]; struct list_lru_one *l; struct list_head *item, *n; unsigned long isolated = 0; - l = list_lru_from_memcg_idx(nlru, memcg_idx); + l = list_lru_from_memcg_idx(lru, nid, memcg_idx); restart: list_for_each_safe(item, n, &l->list) { enum lru_status ret; @@ -272,8 +273,8 @@ list_lru_walk_one(struct list_lru *lru, int nid, struct mem_cgroup *memcg, unsigned long ret; spin_lock(&nlru->lock); - ret = __list_lru_walk_one(nlru, memcg_cache_id(memcg), isolate, cb_arg, - nr_to_walk); + ret = __list_lru_walk_one(lru, nid, memcg_cache_id(memcg), isolate, + cb_arg, nr_to_walk); spin_unlock(&nlru->lock); return ret; } @@ -288,8 +289,8 @@ list_lru_walk_one_irq(struct list_lru *lru, int nid, struct mem_cgroup *memcg, unsigned long ret; spin_lock_irq(&nlru->lock); - ret = __list_lru_walk_one(nlru, memcg_cache_id(memcg), isolate, cb_arg, - nr_to_walk); + ret = __list_lru_walk_one(lru, nid, memcg_cache_id(memcg), isolate, + cb_arg, nr_to_walk); spin_unlock_irq(&nlru->lock); return ret; } @@ -308,7 +309,7 @@ unsigned long list_lru_walk_node(struct list_lru *lru, int nid, struct list_lru_node *nlru = &lru->node[nid]; spin_lock(&nlru->lock); - isolated += __list_lru_walk_one(nlru, memcg_idx, + isolated += __list_lru_walk_one(lru, nid, memcg_idx, isolate, cb_arg, nr_to_walk); spin_unlock(&nlru->lock); @@ -328,166 +329,111 @@ static void init_one_lru(struct list_lru_one *l) } #ifdef CONFIG_MEMCG_KMEM -static void __memcg_destroy_list_lru_node(struct list_lru_memcg *memcg_lrus, - int begin, int end) +static void memcg_destroy_list_lru_range(struct list_lru_memcg *mlrus, + int begin, int end) { int i; for (i = begin; i < end; i++) - kfree(memcg_lrus->lru[i]); + kfree(mlrus->mlru[i]); } -static int __memcg_init_list_lru_node(struct list_lru_memcg *memcg_lrus, - int begin, int end) +static int memcg_init_list_lru_range(struct list_lru_memcg *mlrus, + int begin, int end) { int i; for (i = begin; i < end; i++) { - struct list_lru_one *l; + int nid; + struct list_lru_per_memcg *mlru; - l = kmalloc(sizeof(struct list_lru_one), GFP_KERNEL); - if (!l) + mlru = kmalloc(struct_size(mlru, node, nr_node_ids), GFP_KERNEL); + if (!mlru) goto fail; - init_one_lru(l); - memcg_lrus->lru[i] = l; + for_each_node(nid) + init_one_lru(&mlru->node[nid]); + mlrus->mlru[i] = mlru; } return 0; fail: - __memcg_destroy_list_lru_node(memcg_lrus, begin, i); + memcg_destroy_list_lru_range(mlrus, begin, i); return -ENOMEM; } -static int memcg_init_list_lru_node(struct list_lru_node *nlru) +static int memcg_init_list_lru(struct list_lru *lru, bool memcg_aware) { - struct list_lru_memcg *memcg_lrus; + struct list_lru_memcg *mlrus; int size = memcg_nr_cache_ids; - memcg_lrus = kvmalloc(struct_size(memcg_lrus, lru, size), GFP_KERNEL); - if (!memcg_lrus) + lru->memcg_aware = memcg_aware; + if (!memcg_aware) + return 0; + + mlrus = kvmalloc(struct_size(mlrus, mlru, size), GFP_KERNEL); + if (!mlrus) return -ENOMEM; - if (__memcg_init_list_lru_node(memcg_lrus, 0, size)) { - kvfree(memcg_lrus); + if (memcg_init_list_lru_range(mlrus, 0, size)) { + kvfree(mlrus); return -ENOMEM; } - RCU_INIT_POINTER(nlru->memcg_lrus, memcg_lrus); + RCU_INIT_POINTER(lru->mlrus, mlrus); return 0; } -static void memcg_destroy_list_lru_node(struct list_lru_node *nlru) +static void memcg_destroy_list_lru(struct list_lru *lru) { - struct list_lru_memcg *memcg_lrus; + struct list_lru_memcg *mlrus; + + if (!list_lru_memcg_aware(lru)) + return; + /* * This is called when shrinker has already been unregistered, * and nobody can use it. So, there is no need to use kvfree_rcu(). */ - memcg_lrus = rcu_dereference_protected(nlru->memcg_lrus, true); - __memcg_destroy_list_lru_node(memcg_lrus, 0, memcg_nr_cache_ids); - kvfree(memcg_lrus); + mlrus = rcu_dereference_protected(lru->mlrus, true); + memcg_destroy_list_lru_range(mlrus, 0, memcg_nr_cache_ids); + kvfree(mlrus); } -static int memcg_update_list_lru_node(struct list_lru_node *nlru, - int old_size, int new_size) +static int memcg_update_list_lru(struct list_lru *lru, int old_size, int new_size) { struct list_lru_memcg *old, *new; BUG_ON(old_size > new_size); - old = rcu_dereference_protected(nlru->memcg_lrus, + old = rcu_dereference_protected(lru->mlrus, lockdep_is_held(&list_lrus_mutex)); - new = kvmalloc(struct_size(new, lru, new_size), GFP_KERNEL); + new = kvmalloc(struct_size(new, mlru, new_size), GFP_KERNEL); if (!new) return -ENOMEM; - if (__memcg_init_list_lru_node(new, old_size, new_size)) { + if (memcg_init_list_lru_range(new, old_size, new_size)) { kvfree(new); return -ENOMEM; } - memcpy(&new->lru, &old->lru, flex_array_size(new, lru, old_size)); - rcu_assign_pointer(nlru->memcg_lrus, new); + memcpy(&new->mlru, &old->mlru, flex_array_size(new, mlru, old_size)); + rcu_assign_pointer(lru->mlrus, new); kvfree_rcu(old, rcu); return 0; } -static void memcg_cancel_update_list_lru_node(struct list_lru_node *nlru, - int old_size, int new_size) -{ - struct list_lru_memcg *memcg_lrus; - - memcg_lrus = rcu_dereference_protected(nlru->memcg_lrus, - lockdep_is_held(&list_lrus_mutex)); - /* do not bother shrinking the array back to the old size, because we - * cannot handle allocation failures here */ - __memcg_destroy_list_lru_node(memcg_lrus, old_size, new_size); -} - -static int memcg_init_list_lru(struct list_lru *lru, bool memcg_aware) -{ - int i; - - lru->memcg_aware = memcg_aware; - - if (!memcg_aware) - return 0; - - for_each_node(i) { - if (memcg_init_list_lru_node(&lru->node[i])) - goto fail; - } - return 0; -fail: - for (i = i - 1; i >= 0; i--) { - if (!lru->node[i].memcg_lrus) - continue; - memcg_destroy_list_lru_node(&lru->node[i]); - } - return -ENOMEM; -} - -static void memcg_destroy_list_lru(struct list_lru *lru) -{ - int i; - - if (!list_lru_memcg_aware(lru)) - return; - - for_each_node(i) - memcg_destroy_list_lru_node(&lru->node[i]); -} - -static int memcg_update_list_lru(struct list_lru *lru, - int old_size, int new_size) -{ - int i; - - for_each_node(i) { - if (memcg_update_list_lru_node(&lru->node[i], - old_size, new_size)) - goto fail; - } - return 0; -fail: - for (i = i - 1; i >= 0; i--) { - if (!lru->node[i].memcg_lrus) - continue; - - memcg_cancel_update_list_lru_node(&lru->node[i], - old_size, new_size); - } - return -ENOMEM; -} - static void memcg_cancel_update_list_lru(struct list_lru *lru, int old_size, int new_size) { - int i; + struct list_lru_memcg *mlrus; - for_each_node(i) - memcg_cancel_update_list_lru_node(&lru->node[i], - old_size, new_size); + mlrus = rcu_dereference_protected(lru->mlrus, + lockdep_is_held(&list_lrus_mutex)); + /* + * Do not bother shrinking the array back to the old size, because we + * cannot handle allocation failures here. + */ + memcg_destroy_list_lru_range(mlrus, old_size, new_size); } int memcg_update_all_list_lrus(int new_size) @@ -524,8 +470,8 @@ static void memcg_drain_list_lru_node(struct list_lru *lru, int nid, */ spin_lock_irq(&nlru->lock); - src = list_lru_from_memcg_idx(nlru, src_idx); - dst = list_lru_from_memcg_idx(nlru, dst_idx); + src = list_lru_from_memcg_idx(lru, nid, src_idx); + dst = list_lru_from_memcg_idx(lru, nid, dst_idx); list_splice_init(&src->list, &dst->list); -- cgit v1.2.3 From 88f2ef73fd66491a2f9a82373d22ca6540f23c62 Mon Sep 17 00:00:00 2001 From: Muchun Song Date: Tue, 22 Mar 2022 14:40:56 -0700 Subject: mm: introduce kmem_cache_alloc_lru We currently allocate scope for every memcg to be able to tracked on every superblock instantiated in the system, regardless of whether that superblock is even accessible to that memcg. These huge memcg counts come from container hosts where memcgs are confined to just a small subset of the total number of superblocks that instantiated at any given point in time. For these systems with huge container counts, list_lru does not need the capability of tracking every memcg on every superblock. What it comes down to is that adding the memcg to the list_lru at the first insert. So introduce kmem_cache_alloc_lru to allocate objects and its list_lru. In the later patch, we will convert all inode and dentry allocation from kmem_cache_alloc to kmem_cache_alloc_lru. Link: https://lkml.kernel.org/r/20220228122126.37293-3-songmuchun@bytedance.com Signed-off-by: Muchun Song Cc: Alex Shi Cc: Anna Schumaker Cc: Chao Yu Cc: Dave Chinner Cc: Fam Zheng Cc: Jaegeuk Kim Cc: Johannes Weiner Cc: Kari Argillander Cc: Matthew Wilcox (Oracle) Cc: Michal Hocko Cc: Qi Zheng Cc: Roman Gushchin Cc: Shakeel Butt Cc: Theodore Ts'o Cc: Trond Myklebust Cc: Vladimir Davydov Cc: Vlastimil Babka Cc: Wei Yang Cc: Xiongchun Duan Cc: Yang Shi Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/list_lru.h | 4 ++ include/linux/memcontrol.h | 14 ++++++ include/linux/slab.h | 3 ++ mm/list_lru.c | 104 +++++++++++++++++++++++++++++++++++++++++---- mm/memcontrol.c | 14 ------ mm/slab.c | 39 +++++++++++------ mm/slab.h | 25 +++++++++-- mm/slob.c | 6 +++ mm/slub.c | 42 ++++++++++++------ 9 files changed, 198 insertions(+), 53 deletions(-) (limited to 'include/linux') diff --git a/include/linux/list_lru.h b/include/linux/list_lru.h index 729a27b6ff53..ab912c49334f 100644 --- a/include/linux/list_lru.h +++ b/include/linux/list_lru.h @@ -56,6 +56,8 @@ struct list_lru { struct list_head list; int shrinker_id; bool memcg_aware; + /* protects ->mlrus->mlru[i] */ + spinlock_t lock; /* for cgroup aware lrus points to per cgroup lists, otherwise NULL */ struct list_lru_memcg __rcu *mlrus; #endif @@ -72,6 +74,8 @@ int __list_lru_init(struct list_lru *lru, bool memcg_aware, #define list_lru_init_memcg(lru, shrinker) \ __list_lru_init((lru), true, NULL, shrinker) +int memcg_list_lru_alloc(struct mem_cgroup *memcg, struct list_lru *lru, + gfp_t gfp); int memcg_update_all_list_lrus(int num_memcgs); void memcg_drain_all_list_lrus(int src_idx, struct mem_cgroup *dst_memcg); diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h index ef4b445392a9..b636732f0c14 100644 --- a/include/linux/memcontrol.h +++ b/include/linux/memcontrol.h @@ -524,6 +524,20 @@ static inline struct mem_cgroup *page_memcg_check(struct page *page) return (struct mem_cgroup *)(memcg_data & ~MEMCG_DATA_FLAGS_MASK); } +static inline struct mem_cgroup *get_mem_cgroup_from_objcg(struct obj_cgroup *objcg) +{ + struct mem_cgroup *memcg; + + rcu_read_lock(); +retry: + memcg = obj_cgroup_memcg(objcg); + if (unlikely(!css_tryget(&memcg->css))) + goto retry; + rcu_read_unlock(); + + return memcg; +} + #ifdef CONFIG_MEMCG_KMEM /* * folio_memcg_kmem - Check if the folio has the memcg_kmem flag set. diff --git a/include/linux/slab.h b/include/linux/slab.h index 5b6193fd8bd9..e6addaf91afd 100644 --- a/include/linux/slab.h +++ b/include/linux/slab.h @@ -135,6 +135,7 @@ #include +struct list_lru; struct mem_cgroup; /* * struct kmem_cache related prototypes @@ -416,6 +417,8 @@ static __always_inline unsigned int __kmalloc_index(size_t size, void *__kmalloc(size_t size, gfp_t flags) __assume_kmalloc_alignment __alloc_size(1); void *kmem_cache_alloc(struct kmem_cache *s, gfp_t flags) __assume_slab_alignment __malloc; +void *kmem_cache_alloc_lru(struct kmem_cache *s, struct list_lru *lru, + gfp_t gfpflags) __assume_slab_alignment __malloc; void kmem_cache_free(struct kmem_cache *s, void *objp); /* diff --git a/mm/list_lru.c b/mm/list_lru.c index 7d1356241aa8..bffa80527723 100644 --- a/mm/list_lru.c +++ b/mm/list_lru.c @@ -13,6 +13,7 @@ #include #include #include "slab.h" +#include "internal.h" #ifdef CONFIG_MEMCG_KMEM static LIST_HEAD(memcg_list_lrus); @@ -338,22 +339,30 @@ static void memcg_destroy_list_lru_range(struct list_lru_memcg *mlrus, kfree(mlrus->mlru[i]); } +static struct list_lru_per_memcg *memcg_init_list_lru_one(gfp_t gfp) +{ + int nid; + struct list_lru_per_memcg *mlru; + + mlru = kmalloc(struct_size(mlru, node, nr_node_ids), gfp); + if (!mlru) + return NULL; + + for_each_node(nid) + init_one_lru(&mlru->node[nid]); + + return mlru; +} + static int memcg_init_list_lru_range(struct list_lru_memcg *mlrus, int begin, int end) { int i; for (i = begin; i < end; i++) { - int nid; - struct list_lru_per_memcg *mlru; - - mlru = kmalloc(struct_size(mlru, node, nr_node_ids), GFP_KERNEL); - if (!mlru) + mlrus->mlru[i] = memcg_init_list_lru_one(GFP_KERNEL); + if (!mlrus->mlru[i]) goto fail; - - for_each_node(nid) - init_one_lru(&mlru->node[nid]); - mlrus->mlru[i] = mlru; } return 0; fail: @@ -370,6 +379,8 @@ static int memcg_init_list_lru(struct list_lru *lru, bool memcg_aware) if (!memcg_aware) return 0; + spin_lock_init(&lru->lock); + mlrus = kvmalloc(struct_size(mlrus, mlru, size), GFP_KERNEL); if (!mlrus) return -ENOMEM; @@ -416,8 +427,11 @@ static int memcg_update_list_lru(struct list_lru *lru, int old_size, int new_siz return -ENOMEM; } + spin_lock_irq(&lru->lock); memcpy(&new->mlru, &old->mlru, flex_array_size(new, mlru, old_size)); rcu_assign_pointer(lru->mlrus, new); + spin_unlock_irq(&lru->lock); + kvfree_rcu(old, rcu); return 0; } @@ -502,6 +516,78 @@ void memcg_drain_all_list_lrus(int src_idx, struct mem_cgroup *dst_memcg) memcg_drain_list_lru(lru, src_idx, dst_memcg); mutex_unlock(&list_lrus_mutex); } + +static bool memcg_list_lru_allocated(struct mem_cgroup *memcg, + struct list_lru *lru) +{ + bool allocated; + int idx; + + idx = memcg->kmemcg_id; + if (unlikely(idx < 0)) + return true; + + rcu_read_lock(); + allocated = !!rcu_dereference(lru->mlrus)->mlru[idx]; + rcu_read_unlock(); + + return allocated; +} + +int memcg_list_lru_alloc(struct mem_cgroup *memcg, struct list_lru *lru, + gfp_t gfp) +{ + int i; + unsigned long flags; + struct list_lru_memcg *mlrus; + struct list_lru_memcg_table { + struct list_lru_per_memcg *mlru; + struct mem_cgroup *memcg; + } *table; + + if (!list_lru_memcg_aware(lru) || memcg_list_lru_allocated(memcg, lru)) + return 0; + + gfp &= GFP_RECLAIM_MASK; + table = kmalloc_array(memcg->css.cgroup->level, sizeof(*table), gfp); + if (!table) + return -ENOMEM; + + /* + * Because the list_lru can be reparented to the parent cgroup's + * list_lru, we should make sure that this cgroup and all its + * ancestors have allocated list_lru_per_memcg. + */ + for (i = 0; memcg; memcg = parent_mem_cgroup(memcg), i++) { + if (memcg_list_lru_allocated(memcg, lru)) + break; + + table[i].memcg = memcg; + table[i].mlru = memcg_init_list_lru_one(gfp); + if (!table[i].mlru) { + while (i--) + kfree(table[i].mlru); + kfree(table); + return -ENOMEM; + } + } + + spin_lock_irqsave(&lru->lock, flags); + mlrus = rcu_dereference_protected(lru->mlrus, true); + while (i--) { + int index = table[i].memcg->kmemcg_id; + + if (mlrus->mlru[index]) + kfree(table[i].mlru); + else + mlrus->mlru[index] = table[i].mlru; + } + spin_unlock_irqrestore(&lru->lock, flags); + + kfree(table); + + return 0; +} #else static int memcg_init_list_lru(struct list_lru *lru, bool memcg_aware) { diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 85a259515e91..52835528eb2a 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -2805,20 +2805,6 @@ static void commit_charge(struct folio *folio, struct mem_cgroup *memcg) folio->memcg_data = (unsigned long)memcg; } -static struct mem_cgroup *get_mem_cgroup_from_objcg(struct obj_cgroup *objcg) -{ - struct mem_cgroup *memcg; - - rcu_read_lock(); -retry: - memcg = obj_cgroup_memcg(objcg); - if (unlikely(!css_tryget(&memcg->css))) - goto retry; - rcu_read_unlock(); - - return memcg; -} - #ifdef CONFIG_MEMCG_KMEM /* * The allocated objcg pointers array is not accounted directly. diff --git a/mm/slab.c b/mm/slab.c index ddf5737c63d9..d9dec7a8fd79 100644 --- a/mm/slab.c +++ b/mm/slab.c @@ -3211,7 +3211,7 @@ slab_alloc_node(struct kmem_cache *cachep, gfp_t flags, int nodeid, size_t orig_ bool init = false; flags &= gfp_allowed_mask; - cachep = slab_pre_alloc_hook(cachep, &objcg, 1, flags); + cachep = slab_pre_alloc_hook(cachep, NULL, &objcg, 1, flags); if (unlikely(!cachep)) return NULL; @@ -3287,7 +3287,8 @@ __do_cache_alloc(struct kmem_cache *cachep, gfp_t flags) #endif /* CONFIG_NUMA */ static __always_inline void * -slab_alloc(struct kmem_cache *cachep, gfp_t flags, size_t orig_size, unsigned long caller) +slab_alloc(struct kmem_cache *cachep, struct list_lru *lru, gfp_t flags, + size_t orig_size, unsigned long caller) { unsigned long save_flags; void *objp; @@ -3295,7 +3296,7 @@ slab_alloc(struct kmem_cache *cachep, gfp_t flags, size_t orig_size, unsigned lo bool init = false; flags &= gfp_allowed_mask; - cachep = slab_pre_alloc_hook(cachep, &objcg, 1, flags); + cachep = slab_pre_alloc_hook(cachep, lru, &objcg, 1, flags); if (unlikely(!cachep)) return NULL; @@ -3484,6 +3485,18 @@ void ___cache_free(struct kmem_cache *cachep, void *objp, __free_one(ac, objp); } +static __always_inline +void *__kmem_cache_alloc_lru(struct kmem_cache *cachep, struct list_lru *lru, + gfp_t flags) +{ + void *ret = slab_alloc(cachep, lru, flags, cachep->object_size, _RET_IP_); + + trace_kmem_cache_alloc(_RET_IP_, ret, + cachep->object_size, cachep->size, flags); + + return ret; +} + /** * kmem_cache_alloc - Allocate an object * @cachep: The cache to allocate from. @@ -3496,15 +3509,17 @@ void ___cache_free(struct kmem_cache *cachep, void *objp, */ void *kmem_cache_alloc(struct kmem_cache *cachep, gfp_t flags) { - void *ret = slab_alloc(cachep, flags, cachep->object_size, _RET_IP_); - - trace_kmem_cache_alloc(_RET_IP_, ret, - cachep->object_size, cachep->size, flags); - - return ret; + return __kmem_cache_alloc_lru(cachep, NULL, flags); } EXPORT_SYMBOL(kmem_cache_alloc); +void *kmem_cache_alloc_lru(struct kmem_cache *cachep, struct list_lru *lru, + gfp_t flags) +{ + return __kmem_cache_alloc_lru(cachep, lru, flags); +} +EXPORT_SYMBOL(kmem_cache_alloc_lru); + static __always_inline void cache_alloc_debugcheck_after_bulk(struct kmem_cache *s, gfp_t flags, size_t size, void **p, unsigned long caller) @@ -3521,7 +3536,7 @@ int kmem_cache_alloc_bulk(struct kmem_cache *s, gfp_t flags, size_t size, size_t i; struct obj_cgroup *objcg = NULL; - s = slab_pre_alloc_hook(s, &objcg, size, flags); + s = slab_pre_alloc_hook(s, NULL, &objcg, size, flags); if (!s) return 0; @@ -3562,7 +3577,7 @@ kmem_cache_alloc_trace(struct kmem_cache *cachep, gfp_t flags, size_t size) { void *ret; - ret = slab_alloc(cachep, flags, size, _RET_IP_); + ret = slab_alloc(cachep, NULL, flags, size, _RET_IP_); ret = kasan_kmalloc(cachep, ret, size, flags); trace_kmalloc(_RET_IP_, ret, @@ -3689,7 +3704,7 @@ static __always_inline void *__do_kmalloc(size_t size, gfp_t flags, cachep = kmalloc_slab(size, flags); if (unlikely(ZERO_OR_NULL_PTR(cachep))) return cachep; - ret = slab_alloc(cachep, flags, size, caller); + ret = slab_alloc(cachep, NULL, flags, size, caller); ret = kasan_kmalloc(cachep, ret, size, flags); trace_kmalloc(caller, ret, diff --git a/mm/slab.h b/mm/slab.h index c7f2abc2b154..fd7ae2024897 100644 --- a/mm/slab.h +++ b/mm/slab.h @@ -231,6 +231,7 @@ struct kmem_cache { #include #include #include +#include /* * State of the slab allocator. @@ -472,6 +473,7 @@ static inline size_t obj_full_size(struct kmem_cache *s) * Returns false if the allocation should fail. */ static inline bool memcg_slab_pre_alloc_hook(struct kmem_cache *s, + struct list_lru *lru, struct obj_cgroup **objcgp, size_t objects, gfp_t flags) { @@ -487,13 +489,26 @@ static inline bool memcg_slab_pre_alloc_hook(struct kmem_cache *s, if (!objcg) return true; - if (obj_cgroup_charge(objcg, flags, objects * obj_full_size(s))) { - obj_cgroup_put(objcg); - return false; + if (lru) { + int ret; + struct mem_cgroup *memcg; + + memcg = get_mem_cgroup_from_objcg(objcg); + ret = memcg_list_lru_alloc(memcg, lru, flags); + css_put(&memcg->css); + + if (ret) + goto out; } + if (obj_cgroup_charge(objcg, flags, objects * obj_full_size(s))) + goto out; + *objcgp = objcg; return true; +out: + obj_cgroup_put(objcg); + return false; } static inline void memcg_slab_post_alloc_hook(struct kmem_cache *s, @@ -598,6 +613,7 @@ static inline void memcg_free_slab_cgroups(struct slab *slab) } static inline bool memcg_slab_pre_alloc_hook(struct kmem_cache *s, + struct list_lru *lru, struct obj_cgroup **objcgp, size_t objects, gfp_t flags) { @@ -697,6 +713,7 @@ static inline size_t slab_ksize(const struct kmem_cache *s) } static inline struct kmem_cache *slab_pre_alloc_hook(struct kmem_cache *s, + struct list_lru *lru, struct obj_cgroup **objcgp, size_t size, gfp_t flags) { @@ -707,7 +724,7 @@ static inline struct kmem_cache *slab_pre_alloc_hook(struct kmem_cache *s, if (should_failslab(s, flags)) return NULL; - if (!memcg_slab_pre_alloc_hook(s, objcgp, size, flags)) + if (!memcg_slab_pre_alloc_hook(s, lru, objcgp, size, flags)) return NULL; return s; diff --git a/mm/slob.c b/mm/slob.c index 60c5842215f1..8a8795520361 100644 --- a/mm/slob.c +++ b/mm/slob.c @@ -635,6 +635,12 @@ void *kmem_cache_alloc(struct kmem_cache *cachep, gfp_t flags) } EXPORT_SYMBOL(kmem_cache_alloc); + +void *kmem_cache_alloc_lru(struct kmem_cache *cachep, struct list_lru *lru, gfp_t flags) +{ + return slob_alloc_node(cachep, flags, NUMA_NO_NODE); +} +EXPORT_SYMBOL(kmem_cache_alloc_lru); #ifdef CONFIG_NUMA void *__kmalloc_node(size_t size, gfp_t gfp, int node) { diff --git a/mm/slub.c b/mm/slub.c index 261474092e43..07cdd999c3fe 100644 --- a/mm/slub.c +++ b/mm/slub.c @@ -3131,7 +3131,7 @@ static __always_inline void maybe_wipe_obj_freeptr(struct kmem_cache *s, * * Otherwise we can simply pick the next object from the lockless free list. */ -static __always_inline void *slab_alloc_node(struct kmem_cache *s, +static __always_inline void *slab_alloc_node(struct kmem_cache *s, struct list_lru *lru, gfp_t gfpflags, int node, unsigned long addr, size_t orig_size) { void *object; @@ -3141,7 +3141,7 @@ static __always_inline void *slab_alloc_node(struct kmem_cache *s, struct obj_cgroup *objcg = NULL; bool init = false; - s = slab_pre_alloc_hook(s, &objcg, 1, gfpflags); + s = slab_pre_alloc_hook(s, lru, &objcg, 1, gfpflags); if (!s) return NULL; @@ -3232,27 +3232,41 @@ out: return object; } -static __always_inline void *slab_alloc(struct kmem_cache *s, +static __always_inline void *slab_alloc(struct kmem_cache *s, struct list_lru *lru, gfp_t gfpflags, unsigned long addr, size_t orig_size) { - return slab_alloc_node(s, gfpflags, NUMA_NO_NODE, addr, orig_size); + return slab_alloc_node(s, lru, gfpflags, NUMA_NO_NODE, addr, orig_size); } -void *kmem_cache_alloc(struct kmem_cache *s, gfp_t gfpflags) +static __always_inline +void *__kmem_cache_alloc_lru(struct kmem_cache *s, struct list_lru *lru, + gfp_t gfpflags) { - void *ret = slab_alloc(s, gfpflags, _RET_IP_, s->object_size); + void *ret = slab_alloc(s, lru, gfpflags, _RET_IP_, s->object_size); trace_kmem_cache_alloc(_RET_IP_, ret, s->object_size, s->size, gfpflags); return ret; } + +void *kmem_cache_alloc(struct kmem_cache *s, gfp_t gfpflags) +{ + return __kmem_cache_alloc_lru(s, NULL, gfpflags); +} EXPORT_SYMBOL(kmem_cache_alloc); +void *kmem_cache_alloc_lru(struct kmem_cache *s, struct list_lru *lru, + gfp_t gfpflags) +{ + return __kmem_cache_alloc_lru(s, lru, gfpflags); +} +EXPORT_SYMBOL(kmem_cache_alloc_lru); + #ifdef CONFIG_TRACING void *kmem_cache_alloc_trace(struct kmem_cache *s, gfp_t gfpflags, size_t size) { - void *ret = slab_alloc(s, gfpflags, _RET_IP_, size); + void *ret = slab_alloc(s, NULL, gfpflags, _RET_IP_, size); trace_kmalloc(_RET_IP_, ret, size, s->size, gfpflags); ret = kasan_kmalloc(s, ret, size, gfpflags); return ret; @@ -3263,7 +3277,7 @@ EXPORT_SYMBOL(kmem_cache_alloc_trace); #ifdef CONFIG_NUMA void *kmem_cache_alloc_node(struct kmem_cache *s, gfp_t gfpflags, int node) { - void *ret = slab_alloc_node(s, gfpflags, node, _RET_IP_, s->object_size); + void *ret = slab_alloc_node(s, NULL, gfpflags, node, _RET_IP_, s->object_size); trace_kmem_cache_alloc_node(_RET_IP_, ret, s->object_size, s->size, gfpflags, node); @@ -3277,7 +3291,7 @@ void *kmem_cache_alloc_node_trace(struct kmem_cache *s, gfp_t gfpflags, int node, size_t size) { - void *ret = slab_alloc_node(s, gfpflags, node, _RET_IP_, size); + void *ret = slab_alloc_node(s, NULL, gfpflags, node, _RET_IP_, size); trace_kmalloc_node(_RET_IP_, ret, size, s->size, gfpflags, node); @@ -3667,7 +3681,7 @@ int kmem_cache_alloc_bulk(struct kmem_cache *s, gfp_t flags, size_t size, struct obj_cgroup *objcg = NULL; /* memcg and kmem_cache debug support */ - s = slab_pre_alloc_hook(s, &objcg, size, flags); + s = slab_pre_alloc_hook(s, NULL, &objcg, size, flags); if (unlikely(!s)) return false; /* @@ -4417,7 +4431,7 @@ void *__kmalloc(size_t size, gfp_t flags) if (unlikely(ZERO_OR_NULL_PTR(s))) return s; - ret = slab_alloc(s, flags, _RET_IP_, size); + ret = slab_alloc(s, NULL, flags, _RET_IP_, size); trace_kmalloc(_RET_IP_, ret, size, s->size, flags); @@ -4465,7 +4479,7 @@ void *__kmalloc_node(size_t size, gfp_t flags, int node) if (unlikely(ZERO_OR_NULL_PTR(s))) return s; - ret = slab_alloc_node(s, flags, node, _RET_IP_, size); + ret = slab_alloc_node(s, NULL, flags, node, _RET_IP_, size); trace_kmalloc_node(_RET_IP_, ret, size, s->size, flags, node); @@ -4923,7 +4937,7 @@ void *__kmalloc_track_caller(size_t size, gfp_t gfpflags, unsigned long caller) if (unlikely(ZERO_OR_NULL_PTR(s))) return s; - ret = slab_alloc(s, gfpflags, caller, size); + ret = slab_alloc(s, NULL, gfpflags, caller, size); /* Honor the call site pointer we received. */ trace_kmalloc(caller, ret, size, s->size, gfpflags); @@ -4954,7 +4968,7 @@ void *__kmalloc_node_track_caller(size_t size, gfp_t gfpflags, if (unlikely(ZERO_OR_NULL_PTR(s))) return s; - ret = slab_alloc_node(s, gfpflags, node, caller, size); + ret = slab_alloc_node(s, NULL, gfpflags, node, caller, size); /* Honor the call site pointer we received. */ trace_kmalloc_node(caller, ret, size, s->size, gfpflags, node); -- cgit v1.2.3 From 8b9f3ac5b01db85c6cf74c2c3a71280cc3045c9c Mon Sep 17 00:00:00 2001 From: Muchun Song Date: Tue, 22 Mar 2022 14:41:00 -0700 Subject: fs: introduce alloc_inode_sb() to allocate filesystems specific inode The allocated inode cache is supposed to be added to its memcg list_lru which should be allocated as well in advance. That can be done by kmem_cache_alloc_lru() which allocates object and list_lru. The file systems is main user of it. So introduce alloc_inode_sb() to allocate file system specific inodes and set up the inode reclaim context properly. The file system is supposed to use alloc_inode_sb() to allocate inodes. In later patches, we will convert all users to the new API. Link: https://lkml.kernel.org/r/20220228122126.37293-4-songmuchun@bytedance.com Signed-off-by: Muchun Song Reviewed-by: Roman Gushchin Cc: Alex Shi Cc: Anna Schumaker Cc: Chao Yu Cc: Dave Chinner Cc: Fam Zheng Cc: Jaegeuk Kim Cc: Johannes Weiner Cc: Kari Argillander Cc: Matthew Wilcox (Oracle) Cc: Michal Hocko Cc: Qi Zheng Cc: Shakeel Butt Cc: Theodore Ts'o Cc: Trond Myklebust Cc: Vladimir Davydov Cc: Vlastimil Babka Cc: Wei Yang Cc: Xiongchun Duan Cc: Yang Shi Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- Documentation/filesystems/porting.rst | 6 ++++++ fs/inode.c | 2 +- include/linux/fs.h | 11 +++++++++++ 3 files changed, 18 insertions(+), 1 deletion(-) (limited to 'include/linux') diff --git a/Documentation/filesystems/porting.rst b/Documentation/filesystems/porting.rst index bf19fd6b86e7..7c1583dbeb59 100644 --- a/Documentation/filesystems/porting.rst +++ b/Documentation/filesystems/porting.rst @@ -45,6 +45,12 @@ typically between calling iget_locked() and unlocking the inode. At some point that will become mandatory. +**mandatory** + +The foo_inode_info should always be allocated through alloc_inode_sb() rather +than kmem_cache_alloc() or kmalloc() related to set up the inode reclaim context +correctly. + --- **mandatory** diff --git a/fs/inode.c b/fs/inode.c index 63324df6fa27..9d9b422504d1 100644 --- a/fs/inode.c +++ b/fs/inode.c @@ -259,7 +259,7 @@ static struct inode *alloc_inode(struct super_block *sb) if (ops->alloc_inode) inode = ops->alloc_inode(sb); else - inode = kmem_cache_alloc(inode_cachep, GFP_KERNEL); + inode = alloc_inode_sb(sb, inode_cachep, GFP_KERNEL); if (!inode) return NULL; diff --git a/include/linux/fs.h b/include/linux/fs.h index ca9445f6cf3d..58a73e59e4c0 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -42,6 +42,7 @@ #include #include #include +#include #include #include @@ -3114,6 +3115,16 @@ extern void free_inode_nonrcu(struct inode *inode); extern int should_remove_suid(struct dentry *); extern int file_remove_privs(struct file *); +/* + * This must be used for allocating filesystems specific inodes to set + * up the inode reclaim context correctly. + */ +static inline void * +alloc_inode_sb(struct super_block *sb, struct kmem_cache *cache, gfp_t gfp) +{ + return kmem_cache_alloc_lru(cache, &sb->s_inode_lru, gfp); +} + extern void __insert_inode_hash(struct inode *, unsigned long hashval); static inline void insert_inode_hash(struct inode *inode) { -- cgit v1.2.3 From 9bbdc0f324097f72b2354c2f8be4cdffd32679b6 Mon Sep 17 00:00:00 2001 From: Muchun Song Date: Tue, 22 Mar 2022 14:41:12 -0700 Subject: xarray: use kmem_cache_alloc_lru to allocate xa_node The workingset will add the xa_node to the shadow_nodes list. So the allocation of xa_node should be done by kmem_cache_alloc_lru(). Using xas_set_lru() to pass the list_lru which we want to insert xa_node into to set up the xa_node reclaim context correctly. Link: https://lkml.kernel.org/r/20220228122126.37293-9-songmuchun@bytedance.com Signed-off-by: Muchun Song Acked-by: Johannes Weiner Acked-by: Roman Gushchin Cc: Alex Shi Cc: Anna Schumaker Cc: Chao Yu Cc: Dave Chinner Cc: Fam Zheng Cc: Jaegeuk Kim Cc: Kari Argillander Cc: Matthew Wilcox (Oracle) Cc: Michal Hocko Cc: Qi Zheng Cc: Shakeel Butt Cc: Theodore Ts'o Cc: Trond Myklebust Cc: Vladimir Davydov Cc: Vlastimil Babka Cc: Wei Yang Cc: Xiongchun Duan Cc: Yang Shi Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/swap.h | 5 ++++- include/linux/xarray.h | 9 ++++++++- lib/xarray.c | 10 +++++----- mm/workingset.c | 2 +- 4 files changed, 18 insertions(+), 8 deletions(-) (limited to 'include/linux') diff --git a/include/linux/swap.h b/include/linux/swap.h index 1d38d9475c4d..3db431276d82 100644 --- a/include/linux/swap.h +++ b/include/linux/swap.h @@ -334,9 +334,12 @@ void workingset_activation(struct folio *folio); /* Only track the nodes of mappings with shadow entries */ void workingset_update_node(struct xa_node *node); +extern struct list_lru shadow_nodes; #define mapping_set_update(xas, mapping) do { \ - if (!dax_mapping(mapping) && !shmem_mapping(mapping)) \ + if (!dax_mapping(mapping) && !shmem_mapping(mapping)) { \ xas_set_update(xas, workingset_update_node); \ + xas_set_lru(xas, &shadow_nodes); \ + } \ } while (0) /* linux/mm/page_alloc.c */ diff --git a/include/linux/xarray.h b/include/linux/xarray.h index d6d5da6ed735..bb52b786be1b 100644 --- a/include/linux/xarray.h +++ b/include/linux/xarray.h @@ -1317,6 +1317,7 @@ struct xa_state { struct xa_node *xa_node; struct xa_node *xa_alloc; xa_update_node_t xa_update; + struct list_lru *xa_lru; }; /* @@ -1336,7 +1337,8 @@ struct xa_state { .xa_pad = 0, \ .xa_node = XAS_RESTART, \ .xa_alloc = NULL, \ - .xa_update = NULL \ + .xa_update = NULL, \ + .xa_lru = NULL, \ } /** @@ -1631,6 +1633,11 @@ static inline void xas_set_update(struct xa_state *xas, xa_update_node_t update) xas->xa_update = update; } +static inline void xas_set_lru(struct xa_state *xas, struct list_lru *lru) +{ + xas->xa_lru = lru; +} + /** * xas_next_entry() - Advance iterator to next present entry. * @xas: XArray operation state. diff --git a/lib/xarray.c b/lib/xarray.c index 6f47f6375808..b95e92598b9c 100644 --- a/lib/xarray.c +++ b/lib/xarray.c @@ -302,7 +302,7 @@ bool xas_nomem(struct xa_state *xas, gfp_t gfp) } if (xas->xa->xa_flags & XA_FLAGS_ACCOUNT) gfp |= __GFP_ACCOUNT; - xas->xa_alloc = kmem_cache_alloc(radix_tree_node_cachep, gfp); + xas->xa_alloc = kmem_cache_alloc_lru(radix_tree_node_cachep, xas->xa_lru, gfp); if (!xas->xa_alloc) return false; xas->xa_alloc->parent = NULL; @@ -334,10 +334,10 @@ static bool __xas_nomem(struct xa_state *xas, gfp_t gfp) gfp |= __GFP_ACCOUNT; if (gfpflags_allow_blocking(gfp)) { xas_unlock_type(xas, lock_type); - xas->xa_alloc = kmem_cache_alloc(radix_tree_node_cachep, gfp); + xas->xa_alloc = kmem_cache_alloc_lru(radix_tree_node_cachep, xas->xa_lru, gfp); xas_lock_type(xas, lock_type); } else { - xas->xa_alloc = kmem_cache_alloc(radix_tree_node_cachep, gfp); + xas->xa_alloc = kmem_cache_alloc_lru(radix_tree_node_cachep, xas->xa_lru, gfp); } if (!xas->xa_alloc) return false; @@ -371,7 +371,7 @@ static void *xas_alloc(struct xa_state *xas, unsigned int shift) if (xas->xa->xa_flags & XA_FLAGS_ACCOUNT) gfp |= __GFP_ACCOUNT; - node = kmem_cache_alloc(radix_tree_node_cachep, gfp); + node = kmem_cache_alloc_lru(radix_tree_node_cachep, xas->xa_lru, gfp); if (!node) { xas_set_err(xas, -ENOMEM); return NULL; @@ -1014,7 +1014,7 @@ void xas_split_alloc(struct xa_state *xas, void *entry, unsigned int order, void *sibling = NULL; struct xa_node *node; - node = kmem_cache_alloc(radix_tree_node_cachep, gfp); + node = kmem_cache_alloc_lru(radix_tree_node_cachep, xas->xa_lru, gfp); if (!node) goto nomem; node->array = xas->xa; diff --git a/mm/workingset.c b/mm/workingset.c index 8c03afe1d67c..979c7130c266 100644 --- a/mm/workingset.c +++ b/mm/workingset.c @@ -429,7 +429,7 @@ out: * point where they would still be useful. */ -static struct list_lru shadow_nodes; +struct list_lru shadow_nodes; void workingset_update_node(struct xa_node *node) { -- cgit v1.2.3 From 5abc1e37afa0335c52608d640fd30910b2eeda21 Mon Sep 17 00:00:00 2001 From: Muchun Song Date: Tue, 22 Mar 2022 14:41:19 -0700 Subject: mm: list_lru: allocate list_lru_one only when needed In our server, we found a suspected memory leak problem. The kmalloc-32 consumes more than 6GB of memory. Other kmem_caches consume less than 2GB memory. After our in-depth analysis, the memory consumption of kmalloc-32 slab cache is the cause of list_lru_one allocation. crash> p memcg_nr_cache_ids memcg_nr_cache_ids = $2 = 24574 memcg_nr_cache_ids is very large and memory consumption of each list_lru can be calculated with the following formula. num_numa_node * memcg_nr_cache_ids * 32 (kmalloc-32) There are 4 numa nodes in our system, so each list_lru consumes ~3MB. crash> list super_blocks | wc -l 952 Every mount will register 2 list lrus, one is for inode, another is for dentry. There are 952 super_blocks. So the total memory is 952 * 2 * 3 MB (~5.6GB). But the number of memory cgroup is less than 500. So I guess more than 12286 containers have been deployed on this machine (I do not know why there are so many containers, it may be a user's bug or the user really want to do that). And memcg_nr_cache_ids has not been reduced to a suitable value. This can waste a lot of memory. Now the infrastructure for dynamic list_lru_one allocation is ready, so remove statically allocated memory code to save memory. Link: https://lkml.kernel.org/r/20220228122126.37293-11-songmuchun@bytedance.com Signed-off-by: Muchun Song Cc: Alex Shi Cc: Anna Schumaker Cc: Chao Yu Cc: Dave Chinner Cc: Fam Zheng Cc: Jaegeuk Kim Cc: Johannes Weiner Cc: Kari Argillander Cc: Matthew Wilcox (Oracle) Cc: Michal Hocko Cc: Qi Zheng Cc: Roman Gushchin Cc: Shakeel Butt Cc: Theodore Ts'o Cc: Trond Myklebust Cc: Vladimir Davydov Cc: Vlastimil Babka Cc: Wei Yang Cc: Xiongchun Duan Cc: Yang Shi Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/list_lru.h | 7 +-- mm/list_lru.c | 121 ++++++++++++++++++++++++++--------------------- mm/memcontrol.c | 6 ++- 3 files changed, 77 insertions(+), 57 deletions(-) (limited to 'include/linux') diff --git a/include/linux/list_lru.h b/include/linux/list_lru.h index ab912c49334f..c36db6dc2a65 100644 --- a/include/linux/list_lru.h +++ b/include/linux/list_lru.h @@ -32,14 +32,15 @@ struct list_lru_one { }; struct list_lru_per_memcg { + struct rcu_head rcu; /* array of per cgroup per node lists, indexed by node id */ - struct list_lru_one node[0]; + struct list_lru_one node[]; }; struct list_lru_memcg { struct rcu_head rcu; /* array of per cgroup lists, indexed by memcg_cache_id */ - struct list_lru_per_memcg *mlru[]; + struct list_lru_per_memcg __rcu *mlru[]; }; struct list_lru_node { @@ -77,7 +78,7 @@ int __list_lru_init(struct list_lru *lru, bool memcg_aware, int memcg_list_lru_alloc(struct mem_cgroup *memcg, struct list_lru *lru, gfp_t gfp); int memcg_update_all_list_lrus(int num_memcgs); -void memcg_drain_all_list_lrus(int src_idx, struct mem_cgroup *dst_memcg); +void memcg_drain_all_list_lrus(struct mem_cgroup *src, struct mem_cgroup *dst); /** * list_lru_add: add an element to the lru list's tail diff --git a/mm/list_lru.c b/mm/list_lru.c index bffa80527723..fc938d8ff48f 100644 --- a/mm/list_lru.c +++ b/mm/list_lru.c @@ -60,8 +60,12 @@ list_lru_from_memcg_idx(struct list_lru *lru, int nid, int idx) * from relocation (see memcg_update_list_lru). */ mlrus = rcu_dereference_check(lru->mlrus, lockdep_is_held(&nlru->lock)); - if (mlrus && idx >= 0) - return &mlrus->mlru[idx]->node[nid]; + if (mlrus && idx >= 0) { + struct list_lru_per_memcg *mlru; + + mlru = rcu_dereference_check(mlrus->mlru[idx], true); + return mlru ? &mlru->node[nid] : NULL; + } return &nlru->lru; } @@ -188,7 +192,7 @@ unsigned long list_lru_count_one(struct list_lru *lru, rcu_read_lock(); l = list_lru_from_memcg_idx(lru, nid, memcg_cache_id(memcg)); - count = READ_ONCE(l->nr_items); + count = l ? READ_ONCE(l->nr_items) : 0; rcu_read_unlock(); if (unlikely(count < 0)) @@ -217,8 +221,11 @@ __list_lru_walk_one(struct list_lru *lru, int nid, int memcg_idx, struct list_head *item, *n; unsigned long isolated = 0; - l = list_lru_from_memcg_idx(lru, nid, memcg_idx); restart: + l = list_lru_from_memcg_idx(lru, nid, memcg_idx); + if (!l) + goto out; + list_for_each_safe(item, n, &l->list) { enum lru_status ret; @@ -262,6 +269,7 @@ restart: BUG(); } } +out: return isolated; } @@ -354,20 +362,25 @@ static struct list_lru_per_memcg *memcg_init_list_lru_one(gfp_t gfp) return mlru; } -static int memcg_init_list_lru_range(struct list_lru_memcg *mlrus, - int begin, int end) +static void memcg_list_lru_free(struct list_lru *lru, int src_idx) { - int i; + struct list_lru_memcg *mlrus; + struct list_lru_per_memcg *mlru; - for (i = begin; i < end; i++) { - mlrus->mlru[i] = memcg_init_list_lru_one(GFP_KERNEL); - if (!mlrus->mlru[i]) - goto fail; - } - return 0; -fail: - memcg_destroy_list_lru_range(mlrus, begin, i); - return -ENOMEM; + spin_lock_irq(&lru->lock); + mlrus = rcu_dereference_protected(lru->mlrus, true); + mlru = rcu_dereference_protected(mlrus->mlru[src_idx], true); + rcu_assign_pointer(mlrus->mlru[src_idx], NULL); + spin_unlock_irq(&lru->lock); + + /* + * The __list_lru_walk_one() can walk the list of this node. + * We need kvfree_rcu() here. And the walking of the list + * is under lru->node[nid]->lock, which can serve as a RCU + * read-side critical section. + */ + if (mlru) + kvfree_rcu(mlru, rcu); } static int memcg_init_list_lru(struct list_lru *lru, bool memcg_aware) @@ -381,14 +394,10 @@ static int memcg_init_list_lru(struct list_lru *lru, bool memcg_aware) spin_lock_init(&lru->lock); - mlrus = kvmalloc(struct_size(mlrus, mlru, size), GFP_KERNEL); + mlrus = kvzalloc(struct_size(mlrus, mlru, size), GFP_KERNEL); if (!mlrus) return -ENOMEM; - if (memcg_init_list_lru_range(mlrus, 0, size)) { - kvfree(mlrus); - return -ENOMEM; - } RCU_INIT_POINTER(lru->mlrus, mlrus); return 0; @@ -422,13 +431,9 @@ static int memcg_update_list_lru(struct list_lru *lru, int old_size, int new_siz if (!new) return -ENOMEM; - if (memcg_init_list_lru_range(new, old_size, new_size)) { - kvfree(new); - return -ENOMEM; - } - spin_lock_irq(&lru->lock); memcpy(&new->mlru, &old->mlru, flex_array_size(new, mlru, old_size)); + memset(&new->mlru[old_size], 0, flex_array_size(new, mlru, new_size - old_size)); rcu_assign_pointer(lru->mlrus, new); spin_unlock_irq(&lru->lock); @@ -436,20 +441,6 @@ static int memcg_update_list_lru(struct list_lru *lru, int old_size, int new_siz return 0; } -static void memcg_cancel_update_list_lru(struct list_lru *lru, - int old_size, int new_size) -{ - struct list_lru_memcg *mlrus; - - mlrus = rcu_dereference_protected(lru->mlrus, - lockdep_is_held(&list_lrus_mutex)); - /* - * Do not bother shrinking the array back to the old size, because we - * cannot handle allocation failures here. - */ - memcg_destroy_list_lru_range(mlrus, old_size, new_size); -} - int memcg_update_all_list_lrus(int new_size) { int ret = 0; @@ -460,15 +451,10 @@ int memcg_update_all_list_lrus(int new_size) list_for_each_entry(lru, &memcg_list_lrus, list) { ret = memcg_update_list_lru(lru, old_size, new_size); if (ret) - goto fail; + break; } -out: mutex_unlock(&list_lrus_mutex); return ret; -fail: - list_for_each_entry_continue_reverse(lru, &memcg_list_lrus, list) - memcg_cancel_update_list_lru(lru, old_size, new_size); - goto out; } static void memcg_drain_list_lru_node(struct list_lru *lru, int nid, @@ -485,6 +471,8 @@ static void memcg_drain_list_lru_node(struct list_lru *lru, int nid, spin_lock_irq(&nlru->lock); src = list_lru_from_memcg_idx(lru, nid, src_idx); + if (!src) + goto out; dst = list_lru_from_memcg_idx(lru, nid, dst_idx); list_splice_init(&src->list, &dst->list); @@ -494,7 +482,7 @@ static void memcg_drain_list_lru_node(struct list_lru *lru, int nid, set_shrinker_bit(dst_memcg, nid, lru_shrinker_id(lru)); src->nr_items = 0; } - +out: spin_unlock_irq(&nlru->lock); } @@ -505,15 +493,41 @@ static void memcg_drain_list_lru(struct list_lru *lru, for_each_node(i) memcg_drain_list_lru_node(lru, i, src_idx, dst_memcg); + + memcg_list_lru_free(lru, src_idx); } -void memcg_drain_all_list_lrus(int src_idx, struct mem_cgroup *dst_memcg) +void memcg_drain_all_list_lrus(struct mem_cgroup *src, struct mem_cgroup *dst) { + struct cgroup_subsys_state *css; struct list_lru *lru; + int src_idx = src->kmemcg_id; + + /* + * Change kmemcg_id of this cgroup and all its descendants to the + * parent's id, and then move all entries from this cgroup's list_lrus + * to ones of the parent. + * + * After we have finished, all list_lrus corresponding to this cgroup + * are guaranteed to remain empty. So we can safely free this cgroup's + * list lrus in memcg_list_lru_free(). + * + * Changing ->kmemcg_id to the parent can prevent memcg_list_lru_alloc() + * from allocating list lrus for this cgroup after memcg_list_lru_free() + * call. + */ + rcu_read_lock(); + css_for_each_descendant_pre(css, &src->css) { + struct mem_cgroup *memcg; + + memcg = mem_cgroup_from_css(css); + memcg->kmemcg_id = dst->kmemcg_id; + } + rcu_read_unlock(); mutex_lock(&list_lrus_mutex); list_for_each_entry(lru, &memcg_list_lrus, list) - memcg_drain_list_lru(lru, src_idx, dst_memcg); + memcg_drain_list_lru(lru, src_idx, dst); mutex_unlock(&list_lrus_mutex); } @@ -528,7 +542,7 @@ static bool memcg_list_lru_allocated(struct mem_cgroup *memcg, return true; rcu_read_lock(); - allocated = !!rcu_dereference(lru->mlrus)->mlru[idx]; + allocated = !!rcu_access_pointer(rcu_dereference(lru->mlrus)->mlru[idx]); rcu_read_unlock(); return allocated; @@ -576,11 +590,12 @@ int memcg_list_lru_alloc(struct mem_cgroup *memcg, struct list_lru *lru, mlrus = rcu_dereference_protected(lru->mlrus, true); while (i--) { int index = table[i].memcg->kmemcg_id; + struct list_lru_per_memcg *mlru = table[i].mlru; - if (mlrus->mlru[index]) - kfree(table[i].mlru); + if (index < 0 || rcu_dereference_protected(mlrus->mlru[index], true)) + kfree(mlru); else - mlrus->mlru[index] = table[i].mlru; + rcu_assign_pointer(mlrus->mlru[index], mlru); } spin_unlock_irqrestore(&lru->lock, flags); diff --git a/mm/memcontrol.c b/mm/memcontrol.c index f08a0dc2ac36..69c09efc599d 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -3709,6 +3709,10 @@ static void memcg_offline_kmem(struct mem_cgroup *memcg) memcg_reparent_objcgs(memcg, parent); + /* + * memcg_drain_all_list_lrus() can change memcg->kmemcg_id. + * Cache it to local @kmemcg_id. + */ kmemcg_id = memcg->kmemcg_id; /* @@ -3717,7 +3721,7 @@ static void memcg_offline_kmem(struct mem_cgroup *memcg) * The ordering is imposed by list_lru_node->lock taken by * memcg_drain_all_list_lrus(). */ - memcg_drain_all_list_lrus(kmemcg_id, parent); + memcg_drain_all_list_lrus(memcg, parent); memcg_free_cache_id(kmemcg_id); } -- cgit v1.2.3 From 1f391eb270791359ee79031945dbe3afeaec6ce3 Mon Sep 17 00:00:00 2001 From: Muchun Song Date: Tue, 22 Mar 2022 14:41:22 -0700 Subject: mm: list_lru: rename memcg_drain_all_list_lrus to memcg_reparent_list_lrus The purpose of the memcg_drain_all_list_lrus() is list_lrus reparenting. It is very similar to memcg_reparent_objcgs(). Rename it to memcg_reparent_list_lrus() so that the name can more consistent with memcg_reparent_objcgs(). Link: https://lkml.kernel.org/r/20220228122126.37293-12-songmuchun@bytedance.com Signed-off-by: Muchun Song Cc: Alex Shi Cc: Anna Schumaker Cc: Chao Yu Cc: Dave Chinner Cc: Fam Zheng Cc: Jaegeuk Kim Cc: Johannes Weiner Cc: Kari Argillander Cc: Matthew Wilcox (Oracle) Cc: Michal Hocko Cc: Qi Zheng Cc: Roman Gushchin Cc: Shakeel Butt Cc: Theodore Ts'o Cc: Trond Myklebust Cc: Vladimir Davydov Cc: Vlastimil Babka Cc: Wei Yang Cc: Xiongchun Duan Cc: Yang Shi Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/list_lru.h | 2 +- mm/list_lru.c | 24 ++++++++++++------------ mm/memcontrol.c | 6 +++--- 3 files changed, 16 insertions(+), 16 deletions(-) (limited to 'include/linux') diff --git a/include/linux/list_lru.h b/include/linux/list_lru.h index c36db6dc2a65..4b00fd8cb373 100644 --- a/include/linux/list_lru.h +++ b/include/linux/list_lru.h @@ -78,7 +78,7 @@ int __list_lru_init(struct list_lru *lru, bool memcg_aware, int memcg_list_lru_alloc(struct mem_cgroup *memcg, struct list_lru *lru, gfp_t gfp); int memcg_update_all_list_lrus(int num_memcgs); -void memcg_drain_all_list_lrus(struct mem_cgroup *src, struct mem_cgroup *dst); +void memcg_reparent_list_lrus(struct mem_cgroup *memcg, struct mem_cgroup *parent); /** * list_lru_add: add an element to the lru list's tail diff --git a/mm/list_lru.c b/mm/list_lru.c index fc938d8ff48f..488dacd1f8ff 100644 --- a/mm/list_lru.c +++ b/mm/list_lru.c @@ -457,8 +457,8 @@ int memcg_update_all_list_lrus(int new_size) return ret; } -static void memcg_drain_list_lru_node(struct list_lru *lru, int nid, - int src_idx, struct mem_cgroup *dst_memcg) +static void memcg_reparent_list_lru_node(struct list_lru *lru, int nid, + int src_idx, struct mem_cgroup *dst_memcg) { struct list_lru_node *nlru = &lru->node[nid]; int dst_idx = dst_memcg->kmemcg_id; @@ -486,22 +486,22 @@ out: spin_unlock_irq(&nlru->lock); } -static void memcg_drain_list_lru(struct list_lru *lru, - int src_idx, struct mem_cgroup *dst_memcg) +static void memcg_reparent_list_lru(struct list_lru *lru, + int src_idx, struct mem_cgroup *dst_memcg) { int i; for_each_node(i) - memcg_drain_list_lru_node(lru, i, src_idx, dst_memcg); + memcg_reparent_list_lru_node(lru, i, src_idx, dst_memcg); memcg_list_lru_free(lru, src_idx); } -void memcg_drain_all_list_lrus(struct mem_cgroup *src, struct mem_cgroup *dst) +void memcg_reparent_list_lrus(struct mem_cgroup *memcg, struct mem_cgroup *parent) { struct cgroup_subsys_state *css; struct list_lru *lru; - int src_idx = src->kmemcg_id; + int src_idx = memcg->kmemcg_id; /* * Change kmemcg_id of this cgroup and all its descendants to the @@ -517,17 +517,17 @@ void memcg_drain_all_list_lrus(struct mem_cgroup *src, struct mem_cgroup *dst) * call. */ rcu_read_lock(); - css_for_each_descendant_pre(css, &src->css) { - struct mem_cgroup *memcg; + css_for_each_descendant_pre(css, &memcg->css) { + struct mem_cgroup *child; - memcg = mem_cgroup_from_css(css); - memcg->kmemcg_id = dst->kmemcg_id; + child = mem_cgroup_from_css(css); + child->kmemcg_id = parent->kmemcg_id; } rcu_read_unlock(); mutex_lock(&list_lrus_mutex); list_for_each_entry(lru, &memcg_list_lrus, list) - memcg_drain_list_lru(lru, src_idx, dst); + memcg_reparent_list_lru(lru, src_idx, parent); mutex_unlock(&list_lrus_mutex); } diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 69c09efc599d..c36b0a0dbc19 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -3710,7 +3710,7 @@ static void memcg_offline_kmem(struct mem_cgroup *memcg) memcg_reparent_objcgs(memcg, parent); /* - * memcg_drain_all_list_lrus() can change memcg->kmemcg_id. + * memcg_reparent_list_lrus() can change memcg->kmemcg_id. * Cache it to local @kmemcg_id. */ kmemcg_id = memcg->kmemcg_id; @@ -3719,9 +3719,9 @@ static void memcg_offline_kmem(struct mem_cgroup *memcg) * After we have finished memcg_reparent_objcgs(), all list_lrus * corresponding to this cgroup are guaranteed to remain empty. * The ordering is imposed by list_lru_node->lock taken by - * memcg_drain_all_list_lrus(). + * memcg_reparent_list_lrus(). */ - memcg_drain_all_list_lrus(memcg, parent); + memcg_reparent_list_lrus(memcg, parent); memcg_free_cache_id(kmemcg_id); } -- cgit v1.2.3 From bbca91cca9a902de2e9907370e9c1e0a3d1aab0f Mon Sep 17 00:00:00 2001 From: Muchun Song Date: Tue, 22 Mar 2022 14:41:25 -0700 Subject: mm: list_lru: replace linear array with xarray If we run 10k containers in the system, the size of the list_lru_memcg->lrus can be ~96KB per list_lru. When we decrease the number containers, the size of the array will not be shrinked. It is not scalable. The xarray is a good choice for this case. We can save a lot of memory when there are tens of thousands continers in the system. If we use xarray, we also can remove the logic code of resizing array, which can simplify the code. [akpm@linux-foundation.org: remove unused local] Link: https://lkml.kernel.org/r/20220228122126.37293-13-songmuchun@bytedance.com Signed-off-by: Muchun Song Cc: Alex Shi Cc: Anna Schumaker Cc: Chao Yu Cc: Dave Chinner Cc: Fam Zheng Cc: Jaegeuk Kim Cc: Johannes Weiner Cc: Kari Argillander Cc: Matthew Wilcox (Oracle) Cc: Michal Hocko Cc: Qi Zheng Cc: Roman Gushchin Cc: Shakeel Butt Cc: Theodore Ts'o Cc: Trond Myklebust Cc: Vladimir Davydov Cc: Vlastimil Babka Cc: Wei Yang Cc: Xiongchun Duan Cc: Yang Shi Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/list_lru.h | 13 +-- include/linux/memcontrol.h | 23 ----- mm/list_lru.c | 203 +++++++++++++++------------------------------ mm/memcontrol.c | 77 ++--------------- 4 files changed, 73 insertions(+), 243 deletions(-) (limited to 'include/linux') diff --git a/include/linux/list_lru.h b/include/linux/list_lru.h index 4b00fd8cb373..572c263561ac 100644 --- a/include/linux/list_lru.h +++ b/include/linux/list_lru.h @@ -11,6 +11,7 @@ #include #include #include +#include struct mem_cgroup; @@ -37,12 +38,6 @@ struct list_lru_per_memcg { struct list_lru_one node[]; }; -struct list_lru_memcg { - struct rcu_head rcu; - /* array of per cgroup lists, indexed by memcg_cache_id */ - struct list_lru_per_memcg __rcu *mlru[]; -}; - struct list_lru_node { /* protects all lists on the node, including per cgroup */ spinlock_t lock; @@ -57,10 +52,7 @@ struct list_lru { struct list_head list; int shrinker_id; bool memcg_aware; - /* protects ->mlrus->mlru[i] */ - spinlock_t lock; - /* for cgroup aware lrus points to per cgroup lists, otherwise NULL */ - struct list_lru_memcg __rcu *mlrus; + struct xarray xa; #endif }; @@ -77,7 +69,6 @@ int __list_lru_init(struct list_lru *lru, bool memcg_aware, int memcg_list_lru_alloc(struct mem_cgroup *memcg, struct list_lru *lru, gfp_t gfp); -int memcg_update_all_list_lrus(int num_memcgs); void memcg_reparent_list_lrus(struct mem_cgroup *memcg, struct mem_cgroup *parent); /** diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h index b636732f0c14..066b7a3b8a9e 100644 --- a/include/linux/memcontrol.h +++ b/include/linux/memcontrol.h @@ -1685,18 +1685,6 @@ void obj_cgroup_uncharge(struct obj_cgroup *objcg, size_t size); extern struct static_key_false memcg_kmem_enabled_key; -extern int memcg_nr_cache_ids; -void memcg_get_cache_ids(void); -void memcg_put_cache_ids(void); - -/* - * Helper macro to loop through all memcg-specific caches. Callers must still - * check if the cache is valid (it is either valid or NULL). - * the slab_mutex must be held when looping through those caches - */ -#define for_each_memcg_cache_index(_idx) \ - for ((_idx) = 0; (_idx) < memcg_nr_cache_ids; (_idx)++) - static inline bool memcg_kmem_enabled(void) { return static_branch_likely(&memcg_kmem_enabled_key); @@ -1753,9 +1741,6 @@ static inline void __memcg_kmem_uncharge_page(struct page *page, int order) { } -#define for_each_memcg_cache_index(_idx) \ - for (; NULL; ) - static inline bool memcg_kmem_enabled(void) { return false; @@ -1766,14 +1751,6 @@ static inline int memcg_cache_id(struct mem_cgroup *memcg) return -1; } -static inline void memcg_get_cache_ids(void) -{ -} - -static inline void memcg_put_cache_ids(void) -{ -} - static inline struct mem_cgroup *mem_cgroup_from_obj(void *p) { return NULL; diff --git a/mm/list_lru.c b/mm/list_lru.c index 488dacd1f8ff..3fdae1688f82 100644 --- a/mm/list_lru.c +++ b/mm/list_lru.c @@ -52,21 +52,12 @@ static int lru_shrinker_id(struct list_lru *lru) static inline struct list_lru_one * list_lru_from_memcg_idx(struct list_lru *lru, int nid, int idx) { - struct list_lru_memcg *mlrus; - struct list_lru_node *nlru = &lru->node[nid]; - - /* - * Either lock or RCU protects the array of per cgroup lists - * from relocation (see memcg_update_list_lru). - */ - mlrus = rcu_dereference_check(lru->mlrus, lockdep_is_held(&nlru->lock)); - if (mlrus && idx >= 0) { - struct list_lru_per_memcg *mlru; + if (list_lru_memcg_aware(lru) && idx >= 0) { + struct list_lru_per_memcg *mlru = xa_load(&lru->xa, idx); - mlru = rcu_dereference_check(mlrus->mlru[idx], true); return mlru ? &mlru->node[nid] : NULL; } - return &nlru->lru; + return &lru->node[nid].lru; } static inline struct list_lru_one * @@ -77,7 +68,7 @@ list_lru_from_kmem(struct list_lru *lru, int nid, void *ptr, struct list_lru_one *l = &nlru->lru; struct mem_cgroup *memcg = NULL; - if (!lru->mlrus) + if (!list_lru_memcg_aware(lru)) goto out; memcg = mem_cgroup_from_obj(ptr); @@ -309,16 +300,20 @@ unsigned long list_lru_walk_node(struct list_lru *lru, int nid, unsigned long *nr_to_walk) { long isolated = 0; - int memcg_idx; isolated += list_lru_walk_one(lru, nid, NULL, isolate, cb_arg, nr_to_walk); + +#ifdef CONFIG_MEMCG_KMEM if (*nr_to_walk > 0 && list_lru_memcg_aware(lru)) { - for_each_memcg_cache_index(memcg_idx) { + struct list_lru_per_memcg *mlru; + unsigned long index; + + xa_for_each(&lru->xa, index, mlru) { struct list_lru_node *nlru = &lru->node[nid]; spin_lock(&nlru->lock); - isolated += __list_lru_walk_one(lru, nid, memcg_idx, + isolated += __list_lru_walk_one(lru, nid, index, isolate, cb_arg, nr_to_walk); spin_unlock(&nlru->lock); @@ -327,6 +322,8 @@ unsigned long list_lru_walk_node(struct list_lru *lru, int nid, break; } } +#endif + return isolated; } EXPORT_SYMBOL_GPL(list_lru_walk_node); @@ -338,15 +335,6 @@ static void init_one_lru(struct list_lru_one *l) } #ifdef CONFIG_MEMCG_KMEM -static void memcg_destroy_list_lru_range(struct list_lru_memcg *mlrus, - int begin, int end) -{ - int i; - - for (i = begin; i < end; i++) - kfree(mlrus->mlru[i]); -} - static struct list_lru_per_memcg *memcg_init_list_lru_one(gfp_t gfp) { int nid; @@ -364,14 +352,7 @@ static struct list_lru_per_memcg *memcg_init_list_lru_one(gfp_t gfp) static void memcg_list_lru_free(struct list_lru *lru, int src_idx) { - struct list_lru_memcg *mlrus; - struct list_lru_per_memcg *mlru; - - spin_lock_irq(&lru->lock); - mlrus = rcu_dereference_protected(lru->mlrus, true); - mlru = rcu_dereference_protected(mlrus->mlru[src_idx], true); - rcu_assign_pointer(mlrus->mlru[src_idx], NULL); - spin_unlock_irq(&lru->lock); + struct list_lru_per_memcg *mlru = xa_erase_irq(&lru->xa, src_idx); /* * The __list_lru_walk_one() can walk the list of this node. @@ -383,78 +364,27 @@ static void memcg_list_lru_free(struct list_lru *lru, int src_idx) kvfree_rcu(mlru, rcu); } -static int memcg_init_list_lru(struct list_lru *lru, bool memcg_aware) +static inline void memcg_init_list_lru(struct list_lru *lru, bool memcg_aware) { - struct list_lru_memcg *mlrus; - int size = memcg_nr_cache_ids; - + if (memcg_aware) + xa_init_flags(&lru->xa, XA_FLAGS_LOCK_IRQ); lru->memcg_aware = memcg_aware; - if (!memcg_aware) - return 0; - - spin_lock_init(&lru->lock); - - mlrus = kvzalloc(struct_size(mlrus, mlru, size), GFP_KERNEL); - if (!mlrus) - return -ENOMEM; - - RCU_INIT_POINTER(lru->mlrus, mlrus); - - return 0; } static void memcg_destroy_list_lru(struct list_lru *lru) { - struct list_lru_memcg *mlrus; + XA_STATE(xas, &lru->xa, 0); + struct list_lru_per_memcg *mlru; if (!list_lru_memcg_aware(lru)) return; - /* - * This is called when shrinker has already been unregistered, - * and nobody can use it. So, there is no need to use kvfree_rcu(). - */ - mlrus = rcu_dereference_protected(lru->mlrus, true); - memcg_destroy_list_lru_range(mlrus, 0, memcg_nr_cache_ids); - kvfree(mlrus); -} - -static int memcg_update_list_lru(struct list_lru *lru, int old_size, int new_size) -{ - struct list_lru_memcg *old, *new; - - BUG_ON(old_size > new_size); - - old = rcu_dereference_protected(lru->mlrus, - lockdep_is_held(&list_lrus_mutex)); - new = kvmalloc(struct_size(new, mlru, new_size), GFP_KERNEL); - if (!new) - return -ENOMEM; - - spin_lock_irq(&lru->lock); - memcpy(&new->mlru, &old->mlru, flex_array_size(new, mlru, old_size)); - memset(&new->mlru[old_size], 0, flex_array_size(new, mlru, new_size - old_size)); - rcu_assign_pointer(lru->mlrus, new); - spin_unlock_irq(&lru->lock); - - kvfree_rcu(old, rcu); - return 0; -} - -int memcg_update_all_list_lrus(int new_size) -{ - int ret = 0; - struct list_lru *lru; - int old_size = memcg_nr_cache_ids; - - mutex_lock(&list_lrus_mutex); - list_for_each_entry(lru, &memcg_list_lrus, list) { - ret = memcg_update_list_lru(lru, old_size, new_size); - if (ret) - break; + xas_lock_irq(&xas); + xas_for_each(&xas, mlru, ULONG_MAX) { + kfree(mlru); + xas_store(&xas, NULL); } - mutex_unlock(&list_lrus_mutex); - return ret; + xas_unlock_irq(&xas); } static void memcg_reparent_list_lru_node(struct list_lru *lru, int nid, @@ -521,7 +451,7 @@ void memcg_reparent_list_lrus(struct mem_cgroup *memcg, struct mem_cgroup *paren struct mem_cgroup *child; child = mem_cgroup_from_css(css); - child->kmemcg_id = parent->kmemcg_id; + WRITE_ONCE(child->kmemcg_id, parent->kmemcg_id); } rcu_read_unlock(); @@ -531,21 +461,12 @@ void memcg_reparent_list_lrus(struct mem_cgroup *memcg, struct mem_cgroup *paren mutex_unlock(&list_lrus_mutex); } -static bool memcg_list_lru_allocated(struct mem_cgroup *memcg, - struct list_lru *lru) +static inline bool memcg_list_lru_allocated(struct mem_cgroup *memcg, + struct list_lru *lru) { - bool allocated; - int idx; - - idx = memcg->kmemcg_id; - if (unlikely(idx < 0)) - return true; + int idx = memcg->kmemcg_id; - rcu_read_lock(); - allocated = !!rcu_access_pointer(rcu_dereference(lru->mlrus)->mlru[idx]); - rcu_read_unlock(); - - return allocated; + return idx < 0 || xa_load(&lru->xa, idx); } int memcg_list_lru_alloc(struct mem_cgroup *memcg, struct list_lru *lru, @@ -553,11 +474,11 @@ int memcg_list_lru_alloc(struct mem_cgroup *memcg, struct list_lru *lru, { int i; unsigned long flags; - struct list_lru_memcg *mlrus; struct list_lru_memcg_table { struct list_lru_per_memcg *mlru; struct mem_cgroup *memcg; } *table; + XA_STATE(xas, &lru->xa, 0); if (!list_lru_memcg_aware(lru) || memcg_list_lru_allocated(memcg, lru)) return 0; @@ -586,27 +507,48 @@ int memcg_list_lru_alloc(struct mem_cgroup *memcg, struct list_lru *lru, } } - spin_lock_irqsave(&lru->lock, flags); - mlrus = rcu_dereference_protected(lru->mlrus, true); + xas_lock_irqsave(&xas, flags); while (i--) { - int index = table[i].memcg->kmemcg_id; + int index = READ_ONCE(table[i].memcg->kmemcg_id); struct list_lru_per_memcg *mlru = table[i].mlru; - if (index < 0 || rcu_dereference_protected(mlrus->mlru[index], true)) + xas_set(&xas, index); +retry: + if (unlikely(index < 0 || xas_error(&xas) || xas_load(&xas))) { kfree(mlru); - else - rcu_assign_pointer(mlrus->mlru[index], mlru); + } else { + xas_store(&xas, mlru); + if (xas_error(&xas) == -ENOMEM) { + xas_unlock_irqrestore(&xas, flags); + if (xas_nomem(&xas, gfp)) + xas_set_err(&xas, 0); + xas_lock_irqsave(&xas, flags); + /* + * The xas lock has been released, this memcg + * can be reparented before us. So reload + * memcg id. More details see the comments + * in memcg_reparent_list_lrus(). + */ + index = READ_ONCE(table[i].memcg->kmemcg_id); + if (index < 0) + xas_set_err(&xas, 0); + else if (!xas_error(&xas) && index != xas.xa_index) + xas_set(&xas, index); + goto retry; + } + } } - spin_unlock_irqrestore(&lru->lock, flags); - + /* xas_nomem() is used to free memory instead of memory allocation. */ + if (xas.xa_alloc) + xas_nomem(&xas, gfp); + xas_unlock_irqrestore(&xas, flags); kfree(table); - return 0; + return xas_error(&xas); } #else -static int memcg_init_list_lru(struct list_lru *lru, bool memcg_aware) +static inline void memcg_init_list_lru(struct list_lru *lru, bool memcg_aware) { - return 0; } static void memcg_destroy_list_lru(struct list_lru *lru) @@ -618,7 +560,6 @@ int __list_lru_init(struct list_lru *lru, bool memcg_aware, struct lock_class_key *key, struct shrinker *shrinker) { int i; - int err = -ENOMEM; #ifdef CONFIG_MEMCG_KMEM if (shrinker) @@ -626,11 +567,10 @@ int __list_lru_init(struct list_lru *lru, bool memcg_aware, else lru->shrinker_id = -1; #endif - memcg_get_cache_ids(); lru->node = kcalloc(nr_node_ids, sizeof(*lru->node), GFP_KERNEL); if (!lru->node) - goto out; + return -ENOMEM; for_each_node(i) { spin_lock_init(&lru->node[i].lock); @@ -639,18 +579,10 @@ int __list_lru_init(struct list_lru *lru, bool memcg_aware, init_one_lru(&lru->node[i].lru); } - err = memcg_init_list_lru(lru, memcg_aware); - if (err) { - kfree(lru->node); - /* Do this so a list_lru_destroy() doesn't crash: */ - lru->node = NULL; - goto out; - } - + memcg_init_list_lru(lru, memcg_aware); list_lru_register(lru); -out: - memcg_put_cache_ids(); - return err; + + return 0; } EXPORT_SYMBOL_GPL(__list_lru_init); @@ -660,8 +592,6 @@ void list_lru_destroy(struct list_lru *lru) if (!lru->node) return; - memcg_get_cache_ids(); - list_lru_unregister(lru); memcg_destroy_list_lru(lru); @@ -671,6 +601,5 @@ void list_lru_destroy(struct list_lru *lru) #ifdef CONFIG_MEMCG_KMEM lru->shrinker_id = -1; #endif - memcg_put_cache_ids(); } EXPORT_SYMBOL_GPL(list_lru_destroy); diff --git a/mm/memcontrol.c b/mm/memcontrol.c index c36b0a0dbc19..68eb62d10c48 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -351,42 +351,17 @@ static void memcg_reparent_objcgs(struct mem_cgroup *memcg, * This will be used as a shrinker list's index. * The main reason for not using cgroup id for this: * this works better in sparse environments, where we have a lot of memcgs, - * but only a few kmem-limited. Or also, if we have, for instance, 200 - * memcgs, and none but the 200th is kmem-limited, we'd have to have a - * 200 entry array for that. - * - * The current size of the caches array is stored in memcg_nr_cache_ids. It - * will double each time we have to increase it. + * but only a few kmem-limited. */ static DEFINE_IDA(memcg_cache_ida); -int memcg_nr_cache_ids; - -/* Protects memcg_nr_cache_ids */ -static DECLARE_RWSEM(memcg_cache_ids_sem); - -void memcg_get_cache_ids(void) -{ - down_read(&memcg_cache_ids_sem); -} - -void memcg_put_cache_ids(void) -{ - up_read(&memcg_cache_ids_sem); -} /* - * MIN_SIZE is different than 1, because we would like to avoid going through - * the alloc/free process all the time. In a small machine, 4 kmem-limited - * cgroups is a reasonable guess. In the future, it could be a parameter or - * tunable, but that is strictly not necessary. - * * MAX_SIZE should be as large as the number of cgrp_ids. Ideally, we could get * this constant directly from cgroup, but it is understandable that this is * better kept as an internal representation in cgroup.c. In any case, the * cgrp_id space is not getting any smaller, and we don't have to necessarily * increase ours as well if it increases. */ -#define MEMCG_CACHES_MIN_SIZE 4 #define MEMCG_CACHES_MAX_SIZE MEM_CGROUP_ID_MAX /* @@ -2944,49 +2919,6 @@ __always_inline struct obj_cgroup *get_obj_cgroup_from_current(void) return objcg; } -static int memcg_alloc_cache_id(void) -{ - int id, size; - int err; - - id = ida_simple_get(&memcg_cache_ida, - 0, MEMCG_CACHES_MAX_SIZE, GFP_KERNEL); - if (id < 0) - return id; - - if (id < memcg_nr_cache_ids) - return id; - - /* - * There's no space for the new id in memcg_caches arrays, - * so we have to grow them. - */ - down_write(&memcg_cache_ids_sem); - - size = 2 * (id + 1); - if (size < MEMCG_CACHES_MIN_SIZE) - size = MEMCG_CACHES_MIN_SIZE; - else if (size > MEMCG_CACHES_MAX_SIZE) - size = MEMCG_CACHES_MAX_SIZE; - - err = memcg_update_all_list_lrus(size); - if (!err) - memcg_nr_cache_ids = size; - - up_write(&memcg_cache_ids_sem); - - if (err) { - ida_simple_remove(&memcg_cache_ida, id); - return err; - } - return id; -} - -static void memcg_free_cache_id(int id) -{ - ida_simple_remove(&memcg_cache_ida, id); -} - static void memcg_account_kmem(struct mem_cgroup *memcg, int nr_pages) { mod_memcg_state(memcg, MEMCG_KMEM, nr_pages); @@ -3673,13 +3605,14 @@ static int memcg_online_kmem(struct mem_cgroup *memcg) if (unlikely(mem_cgroup_is_root(memcg))) return 0; - memcg_id = memcg_alloc_cache_id(); + memcg_id = ida_alloc_max(&memcg_cache_ida, MEMCG_CACHES_MAX_SIZE - 1, + GFP_KERNEL); if (memcg_id < 0) return memcg_id; objcg = obj_cgroup_alloc(); if (!objcg) { - memcg_free_cache_id(memcg_id); + ida_free(&memcg_cache_ida, memcg_id); return -ENOMEM; } objcg->memcg = memcg; @@ -3723,7 +3656,7 @@ static void memcg_offline_kmem(struct mem_cgroup *memcg) */ memcg_reparent_list_lrus(memcg, parent); - memcg_free_cache_id(kmemcg_id); + ida_free(&memcg_cache_ida, kmemcg_id); } #else static int memcg_online_kmem(struct mem_cgroup *memcg) -- cgit v1.2.3 From d70110704d2d52a65a9fe43be409d8c3acce79fe Mon Sep 17 00:00:00 2001 From: Muchun Song Date: Tue, 22 Mar 2022 14:41:35 -0700 Subject: mm: list_lru: rename list_lru_per_memcg to list_lru_memcg The name of list_lru_memcg was occupied before and became free since last commit. Rename list_lru_per_memcg to list_lru_memcg since the name is brief. Link: https://lkml.kernel.org/r/20220228122126.37293-16-songmuchun@bytedance.com Signed-off-by: Muchun Song Cc: Alex Shi Cc: Anna Schumaker Cc: Chao Yu Cc: Dave Chinner Cc: Fam Zheng Cc: Jaegeuk Kim Cc: Johannes Weiner Cc: Kari Argillander Cc: Matthew Wilcox (Oracle) Cc: Michal Hocko Cc: Qi Zheng Cc: Roman Gushchin Cc: Shakeel Butt Cc: Theodore Ts'o Cc: Trond Myklebust Cc: Vladimir Davydov Cc: Vlastimil Babka Cc: Wei Yang Cc: Xiongchun Duan Cc: Yang Shi Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/list_lru.h | 2 +- mm/list_lru.c | 18 +++++++++--------- 2 files changed, 10 insertions(+), 10 deletions(-) (limited to 'include/linux') diff --git a/include/linux/list_lru.h b/include/linux/list_lru.h index 572c263561ac..b35968ee9fb5 100644 --- a/include/linux/list_lru.h +++ b/include/linux/list_lru.h @@ -32,7 +32,7 @@ struct list_lru_one { long nr_items; }; -struct list_lru_per_memcg { +struct list_lru_memcg { struct rcu_head rcu; /* array of per cgroup per node lists, indexed by node id */ struct list_lru_one node[]; diff --git a/mm/list_lru.c b/mm/list_lru.c index 3fdae1688f82..1e740febc96e 100644 --- a/mm/list_lru.c +++ b/mm/list_lru.c @@ -53,7 +53,7 @@ static inline struct list_lru_one * list_lru_from_memcg_idx(struct list_lru *lru, int nid, int idx) { if (list_lru_memcg_aware(lru) && idx >= 0) { - struct list_lru_per_memcg *mlru = xa_load(&lru->xa, idx); + struct list_lru_memcg *mlru = xa_load(&lru->xa, idx); return mlru ? &mlru->node[nid] : NULL; } @@ -306,7 +306,7 @@ unsigned long list_lru_walk_node(struct list_lru *lru, int nid, #ifdef CONFIG_MEMCG_KMEM if (*nr_to_walk > 0 && list_lru_memcg_aware(lru)) { - struct list_lru_per_memcg *mlru; + struct list_lru_memcg *mlru; unsigned long index; xa_for_each(&lru->xa, index, mlru) { @@ -335,10 +335,10 @@ static void init_one_lru(struct list_lru_one *l) } #ifdef CONFIG_MEMCG_KMEM -static struct list_lru_per_memcg *memcg_init_list_lru_one(gfp_t gfp) +static struct list_lru_memcg *memcg_init_list_lru_one(gfp_t gfp) { int nid; - struct list_lru_per_memcg *mlru; + struct list_lru_memcg *mlru; mlru = kmalloc(struct_size(mlru, node, nr_node_ids), gfp); if (!mlru) @@ -352,7 +352,7 @@ static struct list_lru_per_memcg *memcg_init_list_lru_one(gfp_t gfp) static void memcg_list_lru_free(struct list_lru *lru, int src_idx) { - struct list_lru_per_memcg *mlru = xa_erase_irq(&lru->xa, src_idx); + struct list_lru_memcg *mlru = xa_erase_irq(&lru->xa, src_idx); /* * The __list_lru_walk_one() can walk the list of this node. @@ -374,7 +374,7 @@ static inline void memcg_init_list_lru(struct list_lru *lru, bool memcg_aware) static void memcg_destroy_list_lru(struct list_lru *lru) { XA_STATE(xas, &lru->xa, 0); - struct list_lru_per_memcg *mlru; + struct list_lru_memcg *mlru; if (!list_lru_memcg_aware(lru)) return; @@ -475,7 +475,7 @@ int memcg_list_lru_alloc(struct mem_cgroup *memcg, struct list_lru *lru, int i; unsigned long flags; struct list_lru_memcg_table { - struct list_lru_per_memcg *mlru; + struct list_lru_memcg *mlru; struct mem_cgroup *memcg; } *table; XA_STATE(xas, &lru->xa, 0); @@ -491,7 +491,7 @@ int memcg_list_lru_alloc(struct mem_cgroup *memcg, struct list_lru *lru, /* * Because the list_lru can be reparented to the parent cgroup's * list_lru, we should make sure that this cgroup and all its - * ancestors have allocated list_lru_per_memcg. + * ancestors have allocated list_lru_memcg. */ for (i = 0; memcg; memcg = parent_mem_cgroup(memcg), i++) { if (memcg_list_lru_allocated(memcg, lru)) @@ -510,7 +510,7 @@ int memcg_list_lru_alloc(struct mem_cgroup *memcg, struct list_lru *lru, xas_lock_irqsave(&xas, flags); while (i--) { int index = READ_ONCE(table[i].memcg->kmemcg_id); - struct list_lru_per_memcg *mlru = table[i].mlru; + struct list_lru_memcg *mlru = table[i].mlru; xas_set(&xas, index); retry: -- cgit v1.2.3 From 7c52f65de40ff0e44f821559eb61931d368a4c48 Mon Sep 17 00:00:00 2001 From: Muchun Song Date: Tue, 22 Mar 2022 14:41:38 -0700 Subject: mm: memcontrol: rename memcg_cache_id to memcg_kmem_id The memcg_cache_id() introduced by commit 2633d7a02823 ("slab/slub: consider a memcg parameter in kmem_create_cache") is used to index in the kmem_cache->memcg_params->memcg_caches array. Since kmem_cache->memcg_params.memcg_caches has been removed by commit 9855609bde03 ("mm: memcg/slab: use a single set of kmem_caches for all accounted allocations"). So the name does not need to reflect cache related. Just rename it to memcg_kmem_id. And it can reflect kmem related. Link: https://lkml.kernel.org/r/20220228122126.37293-17-songmuchun@bytedance.com Signed-off-by: Muchun Song Cc: Alex Shi Cc: Anna Schumaker Cc: Chao Yu Cc: Dave Chinner Cc: Fam Zheng Cc: Jaegeuk Kim Cc: Johannes Weiner Cc: Kari Argillander Cc: Matthew Wilcox (Oracle) Cc: Michal Hocko Cc: Qi Zheng Cc: Roman Gushchin Cc: Shakeel Butt Cc: Theodore Ts'o Cc: Trond Myklebust Cc: Vladimir Davydov Cc: Vlastimil Babka Cc: Wei Yang Cc: Xiongchun Duan Cc: Yang Shi Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/memcontrol.h | 4 ++-- mm/list_lru.c | 8 ++++---- 2 files changed, 6 insertions(+), 6 deletions(-) (limited to 'include/linux') diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h index 066b7a3b8a9e..a68dce3873fc 100644 --- a/include/linux/memcontrol.h +++ b/include/linux/memcontrol.h @@ -1708,7 +1708,7 @@ static inline void memcg_kmem_uncharge_page(struct page *page, int order) * A helper for accessing memcg's kmem_id, used for getting * corresponding LRU lists. */ -static inline int memcg_cache_id(struct mem_cgroup *memcg) +static inline int memcg_kmem_id(struct mem_cgroup *memcg) { return memcg ? memcg->kmemcg_id : -1; } @@ -1746,7 +1746,7 @@ static inline bool memcg_kmem_enabled(void) return false; } -static inline int memcg_cache_id(struct mem_cgroup *memcg) +static inline int memcg_kmem_id(struct mem_cgroup *memcg) { return -1; } diff --git a/mm/list_lru.c b/mm/list_lru.c index 1e740febc96e..ba76428ceece 100644 --- a/mm/list_lru.c +++ b/mm/list_lru.c @@ -75,7 +75,7 @@ list_lru_from_kmem(struct list_lru *lru, int nid, void *ptr, if (!memcg) goto out; - l = list_lru_from_memcg_idx(lru, nid, memcg_cache_id(memcg)); + l = list_lru_from_memcg_idx(lru, nid, memcg_kmem_id(memcg)); out: if (memcg_ptr) *memcg_ptr = memcg; @@ -182,7 +182,7 @@ unsigned long list_lru_count_one(struct list_lru *lru, long count; rcu_read_lock(); - l = list_lru_from_memcg_idx(lru, nid, memcg_cache_id(memcg)); + l = list_lru_from_memcg_idx(lru, nid, memcg_kmem_id(memcg)); count = l ? READ_ONCE(l->nr_items) : 0; rcu_read_unlock(); @@ -273,7 +273,7 @@ list_lru_walk_one(struct list_lru *lru, int nid, struct mem_cgroup *memcg, unsigned long ret; spin_lock(&nlru->lock); - ret = __list_lru_walk_one(lru, nid, memcg_cache_id(memcg), isolate, + ret = __list_lru_walk_one(lru, nid, memcg_kmem_id(memcg), isolate, cb_arg, nr_to_walk); spin_unlock(&nlru->lock); return ret; @@ -289,7 +289,7 @@ list_lru_walk_one_irq(struct list_lru *lru, int nid, struct mem_cgroup *memcg, unsigned long ret; spin_lock_irq(&nlru->lock); - ret = __list_lru_walk_one(lru, nid, memcg_cache_id(memcg), isolate, + ret = __list_lru_walk_one(lru, nid, memcg_kmem_id(memcg), isolate, cb_arg, nr_to_walk); spin_unlock_irq(&nlru->lock); return ret; -- cgit v1.2.3 From 16785bd7743104d57257a455001172b75afa7614 Mon Sep 17 00:00:00 2001 From: Anshuman Khandual Date: Tue, 22 Mar 2022 14:41:47 -0700 Subject: mm: merge pte_mkhuge() call into arch_make_huge_pte() Each call into pte_mkhuge() is invariably followed by arch_make_huge_pte(). Instead arch_make_huge_pte() can accommodate pte_mkhuge() at the beginning. This updates generic fallback stub for arch_make_huge_pte() and available platforms definitions. This makes huge pte creation much cleaner and easier to follow. Link: https://lkml.kernel.org/r/1643860669-26307-1-git-send-email-anshuman.khandual@arm.com Signed-off-by: Anshuman Khandual Reviewed-by: Christophe Leroy Acked-by: Mike Kravetz Acked-by: Catalin Marinas Cc: Will Deacon Cc: Michael Ellerman Cc: Paul Mackerras Cc: "David S. Miller" Cc: Mike Kravetz Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/arm64/mm/hugetlbpage.c | 1 + arch/powerpc/include/asm/nohash/32/hugetlb-8xx.h | 4 ++-- arch/sparc/mm/hugetlbpage.c | 1 + include/linux/hugetlb.h | 2 +- mm/hugetlb.c | 3 +-- mm/vmalloc.c | 1 - 6 files changed, 6 insertions(+), 6 deletions(-) (limited to 'include/linux') diff --git a/arch/arm64/mm/hugetlbpage.c b/arch/arm64/mm/hugetlbpage.c index ffb9c229610a..228226c5fa80 100644 --- a/arch/arm64/mm/hugetlbpage.c +++ b/arch/arm64/mm/hugetlbpage.c @@ -347,6 +347,7 @@ pte_t arch_make_huge_pte(pte_t entry, unsigned int shift, vm_flags_t flags) { size_t pagesize = 1UL << shift; + entry = pte_mkhuge(entry); if (pagesize == CONT_PTE_SIZE) { entry = pte_mkcont(entry); } else if (pagesize == CONT_PMD_SIZE) { diff --git a/arch/powerpc/include/asm/nohash/32/hugetlb-8xx.h b/arch/powerpc/include/asm/nohash/32/hugetlb-8xx.h index 64b6c608eca4..de092b04ee1a 100644 --- a/arch/powerpc/include/asm/nohash/32/hugetlb-8xx.h +++ b/arch/powerpc/include/asm/nohash/32/hugetlb-8xx.h @@ -71,9 +71,9 @@ static inline pte_t arch_make_huge_pte(pte_t entry, unsigned int shift, vm_flags size_t size = 1UL << shift; if (size == SZ_16K) - return __pte(pte_val(entry) & ~_PAGE_HUGE); + return __pte(pte_val(entry) | _PAGE_SPS); else - return entry; + return __pte(pte_val(entry) | _PAGE_SPS | _PAGE_HUGE); } #define arch_make_huge_pte arch_make_huge_pte #endif diff --git a/arch/sparc/mm/hugetlbpage.c b/arch/sparc/mm/hugetlbpage.c index 0f49fada2093..d8e0e3c7038d 100644 --- a/arch/sparc/mm/hugetlbpage.c +++ b/arch/sparc/mm/hugetlbpage.c @@ -181,6 +181,7 @@ pte_t arch_make_huge_pte(pte_t entry, unsigned int shift, vm_flags_t flags) { pte_t pte; + entry = pte_mkhuge(entry); pte = hugepage_shift_to_tte(entry, shift); #ifdef CONFIG_SPARC64 diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h index d1897a69c540..52c462390aee 100644 --- a/include/linux/hugetlb.h +++ b/include/linux/hugetlb.h @@ -754,7 +754,7 @@ static inline void arch_clear_hugepage_flags(struct page *page) { } static inline pte_t arch_make_huge_pte(pte_t entry, unsigned int shift, vm_flags_t flags) { - return entry; + return pte_mkhuge(entry); } #endif diff --git a/mm/hugetlb.c b/mm/hugetlb.c index f294db835f4b..a404af0b49a0 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -4637,7 +4637,6 @@ static pte_t make_huge_pte(struct vm_area_struct *vma, struct page *page, vma->vm_page_prot)); } entry = pte_mkyoung(entry); - entry = pte_mkhuge(entry); entry = arch_make_huge_pte(entry, shift, vma->vm_flags); return entry; @@ -6171,7 +6170,7 @@ unsigned long hugetlb_change_protection(struct vm_area_struct *vma, unsigned int shift = huge_page_shift(hstate_vma(vma)); old_pte = huge_ptep_modify_prot_start(vma, address, ptep); - pte = pte_mkhuge(huge_pte_modify(old_pte, newprot)); + pte = huge_pte_modify(old_pte, newprot); pte = arch_make_huge_pte(pte, shift, vma->vm_flags); huge_ptep_modify_prot_commit(vma, address, ptep, old_pte, pte); pages++; diff --git a/mm/vmalloc.c b/mm/vmalloc.c index 4165304d3547..d0b14dd73adc 100644 --- a/mm/vmalloc.c +++ b/mm/vmalloc.c @@ -118,7 +118,6 @@ static int vmap_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end, if (size != PAGE_SIZE) { pte_t entry = pfn_pte(pfn, prot); - entry = pte_mkhuge(entry); entry = arch_make_huge_pte(entry, ilog2(size), 0); set_huge_pte_at(&init_mm, addr, pte, entry); pfn += PFN_DOWN(size); -- cgit v1.2.3 From ff11a7ce1f0f8c1e7870de26860024b4ddbf5755 Mon Sep 17 00:00:00 2001 From: Bang Li Date: Tue, 22 Mar 2022 14:43:02 -0700 Subject: mm/vmalloc: fix comments about vmap_area struct The vmap_area_root should be in the "busy" tree and the free_vmap_area_root should be in the "free" tree. Link: https://lkml.kernel.org/r/20220305011510.33596-1-libang.linuxer@gmail.com Fixes: 688fcbfc06e4 ("mm/vmalloc: modify struct vmap_area to reduce its size") Signed-off-by: Bang Li Reviewed-by: Uladzislau Rezki (Sony) Cc: Pengfei Li Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/vmalloc.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'include/linux') diff --git a/include/linux/vmalloc.h b/include/linux/vmalloc.h index 880227b9f044..05065915edd7 100644 --- a/include/linux/vmalloc.h +++ b/include/linux/vmalloc.h @@ -80,8 +80,8 @@ struct vmap_area { /* * The following two variables can be packed, because * a vmap_area object can be either: - * 1) in "free" tree (root is vmap_area_root) - * 2) or "busy" tree (root is free_vmap_area_root) + * 1) in "free" tree (root is free_vmap_area_root) + * 2) or "busy" tree (root is vmap_area_root) */ union { unsigned long subtree_max_size; /* in "free" tree */ -- cgit v1.2.3 From 1dd214b8f21ca46d5431be9b2db8513c59e07a26 Mon Sep 17 00:00:00 2001 From: Zi Yan Date: Tue, 22 Mar 2022 14:43:05 -0700 Subject: mm: page_alloc: avoid merging non-fallbackable pageblocks with others This is done in addition to MIGRATE_ISOLATE pageblock merge avoidance. It prepares for the upcoming removal of the MAX_ORDER-1 alignment requirement for CMA and alloc_contig_range(). MIGRATE_HIGHATOMIC should not merge with other migratetypes like MIGRATE_ISOLATE and MIGRARTE_CMA[1], so this commit prevents that too. Remove MIGRATE_CMA and MIGRATE_ISOLATE from fallbacks list, since they are never used. [1] https://lore.kernel.org/linux-mm/20211130100853.GP3366@techsingularity.net/ Link: https://lkml.kernel.org/r/20220124175957.1261961-1-zi.yan@sent.com Signed-off-by: Zi Yan Acked-by: Mel Gorman Acked-by: David Hildenbrand Acked-by: Vlastimil Babka Acked-by: Mike Rapoport Reviewed-by: Oscar Salvador Cc: Mike Rapoport Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/mmzone.h | 11 +++++++++++ mm/page_alloc.c | 44 +++++++++++++++++++++----------------------- 2 files changed, 32 insertions(+), 23 deletions(-) (limited to 'include/linux') diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h index aed44e9b5d89..71b77aab748d 100644 --- a/include/linux/mmzone.h +++ b/include/linux/mmzone.h @@ -83,6 +83,17 @@ static inline bool is_migrate_movable(int mt) return is_migrate_cma(mt) || mt == MIGRATE_MOVABLE; } +/* + * Check whether a migratetype can be merged with another migratetype. + * + * It is only mergeable when it can fall back to other migratetypes for + * allocation. See fallbacks[MIGRATE_TYPES][3] in page_alloc.c. + */ +static inline bool migratetype_is_mergeable(int mt) +{ + return mt < MIGRATE_PCPTYPES; +} + #define for_each_migratetype_order(order, type) \ for (order = 0; order < MAX_ORDER; order++) \ for (type = 0; type < MIGRATE_TYPES; type++) diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 3589febc6d31..82f8226b1180 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -1117,25 +1117,24 @@ continue_merging: } if (order < MAX_ORDER - 1) { /* If we are here, it means order is >= pageblock_order. - * We want to prevent merge between freepages on isolate - * pageblock and normal pageblock. Without this, pageblock - * isolation could cause incorrect freepage or CMA accounting. + * We want to prevent merge between freepages on pageblock + * without fallbacks and normal pageblock. Without this, + * pageblock isolation could cause incorrect freepage or CMA + * accounting or HIGHATOMIC accounting. * * We don't want to hit this code for the more frequent * low-order merging. */ - if (unlikely(has_isolate_pageblock(zone))) { - int buddy_mt; + int buddy_mt; - buddy_pfn = __find_buddy_pfn(pfn, order); - buddy = page + (buddy_pfn - pfn); - buddy_mt = get_pageblock_migratetype(buddy); + buddy_pfn = __find_buddy_pfn(pfn, order); + buddy = page + (buddy_pfn - pfn); + buddy_mt = get_pageblock_migratetype(buddy); - if (migratetype != buddy_mt - && (is_migrate_isolate(migratetype) || - is_migrate_isolate(buddy_mt))) - goto done_merging; - } + if (migratetype != buddy_mt + && (!migratetype_is_mergeable(migratetype) || + !migratetype_is_mergeable(buddy_mt))) + goto done_merging; max_order = order + 1; goto continue_merging; } @@ -2479,17 +2478,13 @@ struct page *__rmqueue_smallest(struct zone *zone, unsigned int order, /* * This array describes the order lists are fallen back to when * the free lists for the desirable migrate type are depleted + * + * The other migratetypes do not have fallbacks. */ static int fallbacks[MIGRATE_TYPES][3] = { [MIGRATE_UNMOVABLE] = { MIGRATE_RECLAIMABLE, MIGRATE_MOVABLE, MIGRATE_TYPES }, [MIGRATE_MOVABLE] = { MIGRATE_RECLAIMABLE, MIGRATE_UNMOVABLE, MIGRATE_TYPES }, [MIGRATE_RECLAIMABLE] = { MIGRATE_UNMOVABLE, MIGRATE_MOVABLE, MIGRATE_TYPES }, -#ifdef CONFIG_CMA - [MIGRATE_CMA] = { MIGRATE_TYPES }, /* Never used */ -#endif -#ifdef CONFIG_MEMORY_ISOLATION - [MIGRATE_ISOLATE] = { MIGRATE_TYPES }, /* Never used */ -#endif }; #ifdef CONFIG_CMA @@ -2795,8 +2790,8 @@ static void reserve_highatomic_pageblock(struct page *page, struct zone *zone, /* Yoink! */ mt = get_pageblock_migratetype(page); - if (!is_migrate_highatomic(mt) && !is_migrate_isolate(mt) - && !is_migrate_cma(mt)) { + /* Only reserve normal pageblocks (i.e., they can merge with others) */ + if (migratetype_is_mergeable(mt)) { zone->nr_reserved_highatomic += pageblock_nr_pages; set_pageblock_migratetype(page, MIGRATE_HIGHATOMIC); move_freepages_block(zone, page, MIGRATE_HIGHATOMIC, NULL); @@ -3545,8 +3540,11 @@ int __isolate_free_page(struct page *page, unsigned int order) struct page *endpage = page + (1 << order) - 1; for (; page < endpage; page += pageblock_nr_pages) { int mt = get_pageblock_migratetype(page); - if (!is_migrate_isolate(mt) && !is_migrate_cma(mt) - && !is_migrate_highatomic(mt)) + /* + * Only change normal pageblocks (i.e., they can merge + * with others) + */ + if (migratetype_is_mergeable(mt)) set_pageblock_migratetype(page, MIGRATE_MOVABLE); } -- cgit v1.2.3 From 7f37e49cbd60ef71b82d25cd55b039a65d06387c Mon Sep 17 00:00:00 2001 From: Miaohe Lin Date: Tue, 22 Mar 2022 14:43:11 -0700 Subject: mm/mmzone.h: remove unused macros Remove pgdat_page_nr, nid_page_nr and NODE_MEM_MAP. They are unused now. Link: https://lkml.kernel.org/r/20220127093210.62293-1-linmiaohe@huawei.com Signed-off-by: Miaohe Lin Reviewed-by: David Hildenbrand Reviewed-by: Mike Rapoport Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/mmzone.h | 7 ------- 1 file changed, 7 deletions(-) (limited to 'include/linux') diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h index 71b77aab748d..c9e6a50109b9 100644 --- a/include/linux/mmzone.h +++ b/include/linux/mmzone.h @@ -931,12 +931,6 @@ typedef struct pglist_data { #define node_present_pages(nid) (NODE_DATA(nid)->node_present_pages) #define node_spanned_pages(nid) (NODE_DATA(nid)->node_spanned_pages) -#ifdef CONFIG_FLATMEM -#define pgdat_page_nr(pgdat, pagenr) ((pgdat)->node_mem_map + (pagenr)) -#else -#define pgdat_page_nr(pgdat, pagenr) pfn_to_page((pgdat)->node_start_pfn + (pagenr)) -#endif -#define nid_page_nr(nid, pagenr) pgdat_page_nr(NODE_DATA(nid),(pagenr)) #define node_start_pfn(nid) (NODE_DATA(nid)->node_start_pfn) #define node_end_pfn(nid) pgdat_end_pfn(NODE_DATA(nid)) @@ -1112,7 +1106,6 @@ static inline struct pglist_data *NODE_DATA(int nid) { return &contig_page_data; } -#define NODE_MEM_MAP(nid) mem_map #else /* CONFIG_NUMA */ -- cgit v1.2.3 From e16faf26780fc0c8dd693ea9ee8420a7706cb2f5 Mon Sep 17 00:00:00 2001 From: David Hildenbrand Date: Tue, 22 Mar 2022 14:43:17 -0700 Subject: cma: factor out minimum alignment requirement Patch series "mm: enforce pageblock_order < MAX_ORDER". Having pageblock_order >= MAX_ORDER seems to be able to happen in corner cases and some parts of the kernel are not prepared for it. For example, Aneesh has shown [1] that such kernels can be compiled on ppc64 with 64k base pages by setting FORCE_MAX_ZONEORDER=8, which will run into a WARN_ON_ONCE(order >= MAX_ORDER) in comapction code right during boot. We can get pageblock_order >= MAX_ORDER when the default hugetlb size is bigger than the maximum allocation granularity of the buddy, in which case we are no longer talking about huge pages but instead gigantic pages. Having pageblock_order >= MAX_ORDER can only make alloc_contig_range() of such gigantic pages more likely to succeed. Reliable use of gigantic pages either requires boot time allcoation or CMA, no need to overcomplicate some places in the kernel to optimize for corner cases that are broken in other areas of the kernel. This patch (of 2): Let's enforce pageblock_order < MAX_ORDER and simplify. Especially patch #1 can be regarded a cleanup before: [PATCH v5 0/6] Use pageblock_order for cma and alloc_contig_range alignment. [2] [1] https://lkml.kernel.org/r/87r189a2ks.fsf@linux.ibm.com [2] https://lkml.kernel.org/r/20220211164135.1803616-1-zi.yan@sent.com Link: https://lkml.kernel.org/r/20220214174132.219303-2-david@redhat.com Signed-off-by: David Hildenbrand Reviewed-by: Zi Yan Acked-by: Rob Herring Cc: Aneesh Kumar K.V Cc: Michael Ellerman Cc: Benjamin Herrenschmidt Cc: Paul Mackerras Cc: Frank Rowand Cc: Michael S. Tsirkin Cc: Christoph Hellwig Cc: Marek Szyprowski Cc: Robin Murphy Cc: Minchan Kim Cc: Vlastimil Babka Cc: John Garry via iommu Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/powerpc/include/asm/fadump-internal.h | 5 ----- arch/powerpc/kernel/fadump.c | 2 +- drivers/of/of_reserved_mem.c | 9 +++------ include/linux/cma.h | 9 +++++++++ kernel/dma/contiguous.c | 4 +--- mm/cma.c | 20 +++++--------------- 6 files changed, 19 insertions(+), 30 deletions(-) (limited to 'include/linux') diff --git a/arch/powerpc/include/asm/fadump-internal.h b/arch/powerpc/include/asm/fadump-internal.h index 52189928ec08..81bcb9abb371 100644 --- a/arch/powerpc/include/asm/fadump-internal.h +++ b/arch/powerpc/include/asm/fadump-internal.h @@ -19,11 +19,6 @@ #define memblock_num_regions(memblock_type) (memblock.memblock_type.cnt) -/* Alignment per CMA requirement. */ -#define FADUMP_CMA_ALIGNMENT (PAGE_SIZE << \ - max_t(unsigned long, MAX_ORDER - 1, \ - pageblock_order)) - /* FAD commands */ #define FADUMP_REGISTER 1 #define FADUMP_UNREGISTER 2 diff --git a/arch/powerpc/kernel/fadump.c b/arch/powerpc/kernel/fadump.c index d03e488cfe9c..7eb67201ea41 100644 --- a/arch/powerpc/kernel/fadump.c +++ b/arch/powerpc/kernel/fadump.c @@ -544,7 +544,7 @@ int __init fadump_reserve_mem(void) if (!fw_dump.nocma) { fw_dump.boot_memory_size = ALIGN(fw_dump.boot_memory_size, - FADUMP_CMA_ALIGNMENT); + CMA_MIN_ALIGNMENT_BYTES); } #endif diff --git a/drivers/of/of_reserved_mem.c b/drivers/of/of_reserved_mem.c index 9c0fb962c22b..75caa6f5d36f 100644 --- a/drivers/of/of_reserved_mem.c +++ b/drivers/of/of_reserved_mem.c @@ -22,6 +22,7 @@ #include #include #include +#include #include "of_private.h" @@ -116,12 +117,8 @@ static int __init __reserved_mem_alloc_size(unsigned long node, if (IS_ENABLED(CONFIG_CMA) && of_flat_dt_is_compatible(node, "shared-dma-pool") && of_get_flat_dt_prop(node, "reusable", NULL) - && !nomap) { - unsigned long order = - max_t(unsigned long, MAX_ORDER - 1, pageblock_order); - - align = max(align, (phys_addr_t)PAGE_SIZE << order); - } + && !nomap) + align = max_t(phys_addr_t, align, CMA_MIN_ALIGNMENT_BYTES); prop = of_get_flat_dt_prop(node, "alloc-ranges", &len); if (prop) { diff --git a/include/linux/cma.h b/include/linux/cma.h index bd801023504b..75fe188ec4a1 100644 --- a/include/linux/cma.h +++ b/include/linux/cma.h @@ -20,6 +20,15 @@ #define CMA_MAX_NAME 64 +/* + * TODO: once the buddy -- especially pageblock merging and alloc_contig_range() + * -- can deal with only some pageblocks of a higher-order page being + * MIGRATE_CMA, we can use pageblock_nr_pages. + */ +#define CMA_MIN_ALIGNMENT_PAGES max_t(phys_addr_t, MAX_ORDER_NR_PAGES, \ + pageblock_nr_pages) +#define CMA_MIN_ALIGNMENT_BYTES (PAGE_SIZE * CMA_MIN_ALIGNMENT_PAGES) + struct cma; extern unsigned long totalcma_pages; diff --git a/kernel/dma/contiguous.c b/kernel/dma/contiguous.c index 3d63d91cba5c..6ea80ae42622 100644 --- a/kernel/dma/contiguous.c +++ b/kernel/dma/contiguous.c @@ -399,8 +399,6 @@ static const struct reserved_mem_ops rmem_cma_ops = { static int __init rmem_cma_setup(struct reserved_mem *rmem) { - phys_addr_t align = PAGE_SIZE << max(MAX_ORDER - 1, pageblock_order); - phys_addr_t mask = align - 1; unsigned long node = rmem->fdt_node; bool default_cma = of_get_flat_dt_prop(node, "linux,cma-default", NULL); struct cma *cma; @@ -416,7 +414,7 @@ static int __init rmem_cma_setup(struct reserved_mem *rmem) of_get_flat_dt_prop(node, "no-map", NULL)) return -EINVAL; - if ((rmem->base & mask) || (rmem->size & mask)) { + if (!IS_ALIGNED(rmem->base | rmem->size, CMA_MIN_ALIGNMENT_BYTES)) { pr_err("Reserved memory: incorrect alignment of CMA region\n"); return -EINVAL; } diff --git a/mm/cma.c b/mm/cma.c index bc9ca8f3c487..5a2cd5851658 100644 --- a/mm/cma.c +++ b/mm/cma.c @@ -168,7 +168,6 @@ int __init cma_init_reserved_mem(phys_addr_t base, phys_addr_t size, struct cma **res_cma) { struct cma *cma; - phys_addr_t alignment; /* Sanity checks */ if (cma_area_count == ARRAY_SIZE(cma_areas)) { @@ -179,15 +178,12 @@ int __init cma_init_reserved_mem(phys_addr_t base, phys_addr_t size, if (!size || !memblock_is_region_reserved(base, size)) return -EINVAL; - /* ensure minimal alignment required by mm core */ - alignment = PAGE_SIZE << - max_t(unsigned long, MAX_ORDER - 1, pageblock_order); - /* alignment should be aligned with order_per_bit */ - if (!IS_ALIGNED(alignment >> PAGE_SHIFT, 1 << order_per_bit)) + if (!IS_ALIGNED(CMA_MIN_ALIGNMENT_PAGES, 1 << order_per_bit)) return -EINVAL; - if (ALIGN(base, alignment) != base || ALIGN(size, alignment) != size) + /* ensure minimal alignment required by mm core */ + if (!IS_ALIGNED(base | size, CMA_MIN_ALIGNMENT_BYTES)) return -EINVAL; /* @@ -262,14 +258,8 @@ int __init cma_declare_contiguous_nid(phys_addr_t base, if (alignment && !is_power_of_2(alignment)) return -EINVAL; - /* - * Sanitise input arguments. - * Pages both ends in CMA area could be merged into adjacent unmovable - * migratetype page by page allocator's buddy algorithm. In the case, - * you couldn't get a contiguous memory, which is not what we want. - */ - alignment = max(alignment, (phys_addr_t)PAGE_SIZE << - max_t(unsigned long, MAX_ORDER - 1, pageblock_order)); + /* Sanitise input arguments. */ + alignment = max_t(phys_addr_t, alignment, CMA_MIN_ALIGNMENT_BYTES); if (fixed && base & (alignment - 1)) { ret = -EINVAL; pr_err("Region at %pa must be aligned to %pa bytes\n", -- cgit v1.2.3 From b3d40a2b6d10c9d0424d2b398bf962fb6adad87e Mon Sep 17 00:00:00 2001 From: David Hildenbrand Date: Tue, 22 Mar 2022 14:43:20 -0700 Subject: mm: enforce pageblock_order < MAX_ORDER Some places in the kernel don't really expect pageblock_order >= MAX_ORDER, and it looks like this is only possible in corner cases: 1) CONFIG_DEFERRED_STRUCT_PAGE_INIT we'll end up freeing pageblock_order pages via __free_pages_core(), which cannot possibly work. 2) find_zone_movable_pfns_for_nodes() will roundup the ZONE_MOVABLE start PFN to MAX_ORDER_NR_PAGES. Consequently with a bigger pageblock_order, we could have a single pageblock partially managed by two zones. 3) compaction code runs into __fragmentation_index() with order >= MAX_ORDER, when checking WARN_ON_ONCE(order >= MAX_ORDER). [1] 4) mm/page_reporting.c won't be reporting any pages with default page_reporting_order == pageblock_order, as we'll be skipping the reporting loop inside page_reporting_process_zone(). 5) __rmqueue_fallback() will never be able to steal with ALLOC_NOFRAGMENT. pageblock_order >= MAX_ORDER is weird either way: it's a pure optimization for making alloc_contig_range(), as used for allcoation of gigantic pages, a little more reliable to succeed. However, if there is demand for somewhat reliable allocation of gigantic pages, affected setups should be using CMA or boottime allocations instead. So let's make sure that pageblock_order < MAX_ORDER and simplify. [1] https://lkml.kernel.org/r/87r189a2ks.fsf@linux.ibm.com Link: https://lkml.kernel.org/r/20220214174132.219303-3-david@redhat.com Signed-off-by: David Hildenbrand Reviewed-by: Zi Yan Cc: Aneesh Kumar K.V Cc: Benjamin Herrenschmidt Cc: Christoph Hellwig Cc: Frank Rowand Cc: John Garry via iommu Cc: Marek Szyprowski Cc: Michael Ellerman Cc: Michael S. Tsirkin Cc: Minchan Kim Cc: Paul Mackerras Cc: Rob Herring Cc: Robin Murphy Cc: Vlastimil Babka Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/virtio/virtio_mem.c | 9 +++------ include/linux/cma.h | 3 +-- include/linux/pageblock-flags.h | 7 +++++-- mm/Kconfig | 3 +++ mm/page_alloc.c | 32 ++++++++------------------------ 5 files changed, 20 insertions(+), 34 deletions(-) (limited to 'include/linux') diff --git a/drivers/virtio/virtio_mem.c b/drivers/virtio/virtio_mem.c index 38becd8d578c..e7d6b679596d 100644 --- a/drivers/virtio/virtio_mem.c +++ b/drivers/virtio/virtio_mem.c @@ -2476,13 +2476,10 @@ static int virtio_mem_init_hotplug(struct virtio_mem *vm) VIRTIO_MEM_DEFAULT_OFFLINE_THRESHOLD); /* - * We want subblocks to span at least MAX_ORDER_NR_PAGES and - * pageblock_nr_pages pages. This: - * - Is required for now for alloc_contig_range() to work reliably - - * it doesn't properly handle smaller granularity on ZONE_NORMAL. + * TODO: once alloc_contig_range() works reliably with pageblock + * granularity on ZONE_NORMAL, use pageblock_nr_pages instead. */ - sb_size = max_t(uint64_t, MAX_ORDER_NR_PAGES, - pageblock_nr_pages) * PAGE_SIZE; + sb_size = PAGE_SIZE * MAX_ORDER_NR_PAGES; sb_size = max_t(uint64_t, vm->device_block_size, sb_size); if (sb_size < memory_block_size_bytes() && !force_bbm) { diff --git a/include/linux/cma.h b/include/linux/cma.h index 75fe188ec4a1..b1ba94f1cc9c 100644 --- a/include/linux/cma.h +++ b/include/linux/cma.h @@ -25,8 +25,7 @@ * -- can deal with only some pageblocks of a higher-order page being * MIGRATE_CMA, we can use pageblock_nr_pages. */ -#define CMA_MIN_ALIGNMENT_PAGES max_t(phys_addr_t, MAX_ORDER_NR_PAGES, \ - pageblock_nr_pages) +#define CMA_MIN_ALIGNMENT_PAGES MAX_ORDER_NR_PAGES #define CMA_MIN_ALIGNMENT_BYTES (PAGE_SIZE * CMA_MIN_ALIGNMENT_PAGES) struct cma; diff --git a/include/linux/pageblock-flags.h b/include/linux/pageblock-flags.h index 973fd731a520..83c7248053a1 100644 --- a/include/linux/pageblock-flags.h +++ b/include/linux/pageblock-flags.h @@ -37,8 +37,11 @@ extern unsigned int pageblock_order; #else /* CONFIG_HUGETLB_PAGE_SIZE_VARIABLE */ -/* Huge pages are a constant size */ -#define pageblock_order HUGETLB_PAGE_ORDER +/* + * Huge pages are a constant size, but don't exceed the maximum allocation + * granularity. + */ +#define pageblock_order min_t(unsigned int, HUGETLB_PAGE_ORDER, MAX_ORDER - 1) #endif /* CONFIG_HUGETLB_PAGE_SIZE_VARIABLE */ diff --git a/mm/Kconfig b/mm/Kconfig index 3326ee3903f3..4c91b92e7537 100644 --- a/mm/Kconfig +++ b/mm/Kconfig @@ -262,6 +262,9 @@ config HUGETLB_PAGE_SIZE_VARIABLE HUGETLB_PAGE_ORDER when there are multiple HugeTLB page sizes available on a platform. + Note that the pageblock_order cannot exceed MAX_ORDER - 1 and will be + clamped down to MAX_ORDER - 1. + config CONTIG_ALLOC def_bool (MEMORY_ISOLATION && COMPACTION) || CMA diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 06c683754334..a4efbdad2f2b 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -1072,14 +1072,12 @@ static inline void __free_one_page(struct page *page, int migratetype, fpi_t fpi_flags) { struct capture_control *capc = task_capc(zone); + unsigned int max_order = pageblock_order; unsigned long buddy_pfn; unsigned long combined_pfn; - unsigned int max_order; struct page *buddy; bool to_tail; - max_order = min_t(unsigned int, MAX_ORDER - 1, pageblock_order); - VM_BUG_ON(!zone_is_initialized(zone)); VM_BUG_ON_PAGE(page->flags & PAGE_FLAGS_CHECK_AT_PREP, page); @@ -2259,19 +2257,8 @@ void __init init_cma_reserved_pageblock(struct page *page) } while (++p, --i); set_pageblock_migratetype(page, MIGRATE_CMA); - - if (pageblock_order >= MAX_ORDER) { - i = pageblock_nr_pages; - p = page; - do { - set_page_refcounted(p); - __free_pages(p, MAX_ORDER - 1); - p += MAX_ORDER_NR_PAGES; - } while (i -= MAX_ORDER_NR_PAGES); - } else { - set_page_refcounted(page); - __free_pages(page, pageblock_order); - } + set_page_refcounted(page); + __free_pages(page, pageblock_order); adjust_managed_page_count(page, pageblock_nr_pages); page_zone(page)->cma_pages += pageblock_nr_pages; @@ -7382,16 +7369,15 @@ static inline void setup_usemap(struct zone *zone) {} /* Initialise the number of pages represented by NR_PAGEBLOCK_BITS */ void __init set_pageblock_order(void) { - unsigned int order; + unsigned int order = MAX_ORDER - 1; /* Check that pageblock_nr_pages has not already been setup */ if (pageblock_order) return; - if (HPAGE_SHIFT > PAGE_SHIFT) + /* Don't let pageblocks exceed the maximum allocation granularity. */ + if (HPAGE_SHIFT > PAGE_SHIFT && HUGETLB_PAGE_ORDER < order) order = HUGETLB_PAGE_ORDER; - else - order = MAX_ORDER - 1; /* * Assume the largest contiguous order of interest is a huge page. @@ -8979,14 +8965,12 @@ struct page *has_unmovable_pages(struct zone *zone, struct page *page, #ifdef CONFIG_CONTIG_ALLOC static unsigned long pfn_max_align_down(unsigned long pfn) { - return pfn & ~(max_t(unsigned long, MAX_ORDER_NR_PAGES, - pageblock_nr_pages) - 1); + return ALIGN_DOWN(pfn, MAX_ORDER_NR_PAGES); } static unsigned long pfn_max_align_up(unsigned long pfn) { - return ALIGN(pfn, max_t(unsigned long, MAX_ORDER_NR_PAGES, - pageblock_nr_pages)); + return ALIGN(pfn, MAX_ORDER_NR_PAGES); } #if defined(CONFIG_DYNAMIC_DEBUG) || \ -- cgit v1.2.3 From 1ca75fa7f19d694c58af681fa023295072b03120 Mon Sep 17 00:00:00 2001 From: Oscar Salvador Date: Tue, 22 Mar 2022 14:43:51 -0700 Subject: arch/x86/mm/numa: Do not initialize nodes twice On x86, prior to ("mm: handle uninitialized numa nodes gracecully"), NUMA nodes could be allocated at three different places. - numa_register_memblks - init_cpu_to_node - init_gi_nodes All these calls happen at setup_arch, and have the following order: setup_arch ... x86_numa_init numa_init numa_register_memblks ... init_cpu_to_node init_memory_less_node alloc_node_data free_area_init_memoryless_node init_gi_nodes init_memory_less_node alloc_node_data free_area_init_memoryless_node numa_register_memblks() is only interested in those nodes which have memory, so it skips over any memoryless node it founds. Later on, when we have read ACPI's SRAT table, we call init_cpu_to_node() and init_gi_nodes(), which initialize any memoryless node we might have that have either CPU or Initiator affinity, meaning we allocate pg_data_t struct for them and we mark them as ONLINE. So far so good, but the thing is that after ("mm: handle uninitialized numa nodes gracefully"), we allocate all possible NUMA nodes in free_area_init(), meaning we have a picture like the following: setup_arch x86_numa_init numa_init numa_register_memblks <-- allocate non-memoryless node x86_init.paging.pagetable_init ... free_area_init free_area_init_memoryless <-- allocate memoryless node init_cpu_to_node alloc_node_data <-- allocate memoryless node with CPU free_area_init_memoryless_node init_gi_nodes alloc_node_data <-- allocate memoryless node with Initiator free_area_init_memoryless_node free_area_init() already allocates all possible NUMA nodes, but init_cpu_to_node() and init_gi_nodes() are clueless about that, so they go ahead and allocate a new pg_data_t struct without checking anything, meaning we end up allocating twice. It should be mad clear that this only happens in the case where memoryless NUMA node happens to have a CPU/Initiator affinity. So get rid of init_memory_less_node() and just set the node online. Note that setting the node online is needed, otherwise we choke down the chain when bringup_nonboot_cpus() ends up calling __try_online_node()->register_one_node()->... and we blow up in bus_add_device(). As can be seen here: BUG: kernel NULL pointer dereference, address: 0000000000000060 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 0 P4D 0 Oops: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC PTI CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.17.0-rc4-1-default+ #45 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.0.0-prebuilt.qemu-project.org 04/4 RIP: 0010:bus_add_device+0x5a/0x140 Code: 8b 74 24 20 48 89 df e8 84 96 ff ff 85 c0 89 c5 75 38 48 8b 53 50 48 85 d2 0f 84 bb 00 004 RSP: 0000:ffffc9000022bd10 EFLAGS: 00010246 RAX: 0000000000000000 RBX: ffff888100987400 RCX: ffff8881003e4e19 RDX: ffff8881009a5e00 RSI: ffff888100987400 RDI: ffff888100987400 RBP: 0000000000000000 R08: ffff8881003e4e18 R09: ffff8881003e4c98 R10: 0000000000000000 R11: ffff888100402bc0 R12: ffffffff822ceba0 R13: 0000000000000000 R14: ffff888100987400 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff88853fc00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000060 CR3: 000000000200a001 CR4: 00000000001706b0 Call Trace: device_add+0x4c0/0x910 __register_one_node+0x97/0x2d0 __try_online_node+0x85/0xc0 try_online_node+0x25/0x40 cpu_up+0x4f/0x100 bringup_nonboot_cpus+0x4f/0x60 smp_init+0x26/0x79 kernel_init_freeable+0x130/0x2f1 kernel_init+0x17/0x150 ret_from_fork+0x22/0x30 The reason is simple, by the time bringup_nonboot_cpus() gets called, we did not register the node_subsys bus yet, so we crash when bus_add_device() tries to dereference bus()->p. The following shows the order of the calls: kernel_init_freeable smp_init bringup_nonboot_cpus ... bus_add_device() <- we did not register node_subsys yet do_basic_setup do_initcalls postcore_initcall(register_node_type); register_node_type subsys_system_register subsys_register bus_register <- register node_subsys bus Why setting the node online saves us then? Well, simply because __try_online_node() backs off when the node is online, meaning we do not end up calling register_one_node() in the first place. This is subtle, broken and deserves a deep analysis and thought about how to put this into shape, but for now let us have this easy fix for the leaking memory issue. [osalvador@suse.de: add comments] Link: https://lkml.kernel.org/r/20220221142649.3457-1-osalvador@suse.de Link: https://lkml.kernel.org/r/20220218224302.5282-2-osalvador@suse.de Fixes: da4490c958ad ("mm: handle uninitialized numa nodes gracefully") Signed-off-by: Oscar Salvador Acked-by: Michal Hocko Cc: David Hildenbrand Cc: Rafael Aquini Cc: Dave Hansen Cc: Wei Yang Cc: Dennis Zhou Cc: Alexey Makhalov Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/x86/mm/numa.c | 33 ++++++++++++++++++++------------- include/linux/mm.h | 1 - mm/page_alloc.c | 2 +- 3 files changed, 21 insertions(+), 15 deletions(-) (limited to 'include/linux') diff --git a/arch/x86/mm/numa.c b/arch/x86/mm/numa.c index c6b1213086d6..e8b061557887 100644 --- a/arch/x86/mm/numa.c +++ b/arch/x86/mm/numa.c @@ -738,17 +738,6 @@ void __init x86_numa_init(void) numa_init(dummy_numa_init); } -static void __init init_memory_less_node(int nid) -{ - /* Allocate and initialize node data. Memory-less node is now online.*/ - alloc_node_data(nid); - free_area_init_memoryless_node(nid); - - /* - * All zonelists will be built later in start_kernel() after per cpu - * areas are initialized. - */ -} /* * A node may exist which has one or more Generic Initiators but no CPUs and no @@ -766,9 +755,18 @@ void __init init_gi_nodes(void) { int nid; + /* + * Exclude this node from + * bringup_nonboot_cpus + * cpu_up + * __try_online_node + * register_one_node + * because node_subsys is not initialized yet. + * TODO remove dependency on node_online + */ for_each_node_state(nid, N_GENERIC_INITIATOR) if (!node_online(nid)) - init_memory_less_node(nid); + node_set_online(nid); } /* @@ -798,8 +796,17 @@ void __init init_cpu_to_node(void) if (node == NUMA_NO_NODE) continue; + /* + * Exclude this node from + * bringup_nonboot_cpus + * cpu_up + * __try_online_node + * register_one_node + * because node_subsys is not initialized yet. + * TODO remove dependency on node_online + */ if (!node_online(node)) - init_memory_less_node(node); + node_set_online(node); numa_set_node(cpu, node); } diff --git a/include/linux/mm.h b/include/linux/mm.h index c02a8cc16e4f..d0978235775f 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -2449,7 +2449,6 @@ static inline spinlock_t *pud_lock(struct mm_struct *mm, pud_t *pud) } extern void __init pagecache_init(void); -extern void __init free_area_init_memoryless_node(int nid); extern void free_initmem(void); /* diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 279852eae9db..7d24522b3b54 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -7626,7 +7626,7 @@ static void __init free_area_init_node(int nid) free_area_init_core(pgdat); } -void __init free_area_init_memoryless_node(int nid) +static void __init free_area_init_memoryless_node(int nid) { free_area_init_node(nid); } -- cgit v1.2.3 From 888af2701db79b9b27c7e37f9ede528a5ca53b76 Mon Sep 17 00:00:00 2001 From: Miaohe Lin Date: Tue, 22 Mar 2022 14:44:44 -0700 Subject: mm/memory-failure.c: fix race with changing page compound again Patch series "A few fixup patches for memory failure", v2. This series contains a few patches to fix the race with changing page compound page, make non-LRU movable pages unhandlable and so on. More details can be found in the respective changelogs. There is a race window where we got the compound_head, the hugetlb page could be freed to buddy, or even changed to another compound page just before we try to get hwpoison page. Think about the below race window: CPU 1 CPU 2 memory_failure_hugetlb struct page *head = compound_head(p); hugetlb page might be freed to buddy, or even changed to another compound page. get_hwpoison_page -- page is not what we want now... If this race happens, just bail out. Also MF_MSG_DIFFERENT_PAGE_SIZE is introduced to record this event. [akpm@linux-foundation.org: s@/**@/*@, per Naoya Horiguchi] Link: https://lkml.kernel.org/r/20220312074613.4798-1-linmiaohe@huawei.com Link: https://lkml.kernel.org/r/20220312074613.4798-2-linmiaohe@huawei.com Signed-off-by: Miaohe Lin Acked-by: Naoya Horiguchi Cc: Tony Luck Cc: Borislav Petkov Cc: Mike Kravetz Cc: Yang Shi Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/mm.h | 1 + include/ras/ras_event.h | 1 + mm/memory-failure.c | 12 ++++++++++++ 3 files changed, 14 insertions(+) (limited to 'include/linux') diff --git a/include/linux/mm.h b/include/linux/mm.h index d0978235775f..45a449e8c209 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -3239,6 +3239,7 @@ enum mf_action_page_type { MF_MSG_BUDDY, MF_MSG_DAX, MF_MSG_UNSPLIT_THP, + MF_MSG_DIFFERENT_PAGE_SIZE, MF_MSG_UNKNOWN, }; diff --git a/include/ras/ras_event.h b/include/ras/ras_event.h index d0337a41141c..1e694fd239b9 100644 --- a/include/ras/ras_event.h +++ b/include/ras/ras_event.h @@ -374,6 +374,7 @@ TRACE_EVENT(aer_event, EM ( MF_MSG_BUDDY, "free buddy page" ) \ EM ( MF_MSG_DAX, "dax page" ) \ EM ( MF_MSG_UNSPLIT_THP, "unsplit thp" ) \ + EM ( MF_MSG_DIFFERENT_PAGE_SIZE, "different page size" ) \ EMe ( MF_MSG_UNKNOWN, "unknown page" ) /* diff --git a/mm/memory-failure.c b/mm/memory-failure.c index 086ae4eb3421..7ec855149393 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -732,6 +732,7 @@ static const char * const action_page_types[] = { [MF_MSG_BUDDY] = "free buddy page", [MF_MSG_DAX] = "dax page", [MF_MSG_UNSPLIT_THP] = "unsplit thp", + [MF_MSG_DIFFERENT_PAGE_SIZE] = "different page size", [MF_MSG_UNKNOWN] = "unknown page", }; @@ -1532,6 +1533,17 @@ static int memory_failure_hugetlb(unsigned long pfn, int flags) } lock_page(head); + + /* + * The page could have changed compound pages due to race window. + * If this happens just bail out. + */ + if (!PageHuge(p) || compound_head(p) != head) { + action_result(pfn, MF_MSG_DIFFERENT_PAGE_SIZE, MF_IGNORED); + res = -EBUSY; + goto out; + } + page_flags = head->flags; if (hwpoison_filter(p)) { -- cgit v1.2.3 From 1e7a8181640a620300e98e22223ca3445b349840 Mon Sep 17 00:00:00 2001 From: Vlastimil Babka Date: Tue, 22 Mar 2022 14:44:53 -0700 Subject: mm, fault-injection: declare should_fail_alloc_page() The mm/ directory can almost fully be built with W=1, which would help in local development. One remaining issue is missing prototype for should_fail_alloc_page(). Thus add it next to the should_failslab() prototype. Note the previous attempt by commit f7173090033c ("mm/page_alloc: make should_fail_alloc_page() static") had to be reverted by commit 54aa386661fe as it caused an unresolved symbol error with CONFIG_DEBUG_INFO_BTF=y Link: https://lkml.kernel.org/r/20220314165724.16071-1-vbabka@suse.cz Signed-off-by: Vlastimil Babka Cc: Mel Gorman Cc: Matthew Wilcox Cc: David Hildenbrand Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/fault-inject.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'include/linux') diff --git a/include/linux/fault-inject.h b/include/linux/fault-inject.h index e525f6957c49..2d04f6448cde 100644 --- a/include/linux/fault-inject.h +++ b/include/linux/fault-inject.h @@ -64,6 +64,8 @@ static inline struct dentry *fault_create_debugfs_attr(const char *name, struct kmem_cache; +bool should_fail_alloc_page(gfp_t gfp_mask, unsigned int order); + int should_failslab(struct kmem_cache *s, gfp_t gfpflags); #ifdef CONFIG_FAILSLAB extern bool __should_failslab(struct kmem_cache *s, gfp_t gfpflags); -- cgit v1.2.3 From e7d324850bfcb30df563d144c0363cc44595277d Mon Sep 17 00:00:00 2001 From: Muchun Song Date: Tue, 22 Mar 2022 14:45:00 -0700 Subject: mm: hugetlb: free the 2nd vmemmap page associated with each HugeTLB page Patch series "Free the 2nd vmemmap page associated with each HugeTLB page", v7. This series can minimize the overhead of struct page for 2MB HugeTLB pages significantly. It further reduces the overhead of struct page by 12.5% for a 2MB HugeTLB compared to the previous approach, which means 2GB per 1TB HugeTLB. It is a nice gain. Comments and reviews are welcome. Thanks. The main implementation and details can refer to the commit log of patch 1. In this series, I have changed the following four helpers, the following table shows the impact of the overhead of those helpers. +------------------+-----------------------+ | APIs | head page | tail page | +------------------+-----------+-----------+ | PageHead() | Y | N | +------------------+-----------+-----------+ | PageTail() | Y | N | +------------------+-----------+-----------+ | PageCompound() | N | N | +------------------+-----------+-----------+ | compound_head() | Y | N | +------------------+-----------+-----------+ Y: Overhead is increased. N: Overhead is _NOT_ increased. It shows that the overhead of those helpers on a tail page don't change between "hugetlb_free_vmemmap=on" and "hugetlb_free_vmemmap=off". But the overhead on a head page will be increased when "hugetlb_free_vmemmap=on" (except PageCompound()). So I believe that Matthew Wilcox's folio series will help with this. The users of PageHead() and PageTail() are much less than compound_head() and most users of PageTail() are VM_BUG_ON(), so I have done some tests about the overhead of compound_head() on head pages. I have tested the overhead of calling compound_head() on a head page, which is 2.11ns (Measure the call time of 10 million times compound_head(), and then average). For a head page whose address is not aligned with PAGE_SIZE or a non-compound page, the overhead of compound_head() is 2.54ns which is increased by 20%. For a head page whose address is aligned with PAGE_SIZE, the overhead of compound_head() is 2.97ns which is increased by 40%. Most pages are the former. I do not think the overhead is significant since the overhead of compound_head() itself is low. This patch (of 5): This patch minimizes the overhead of struct page for 2MB HugeTLB pages significantly. It further reduces the overhead of struct page by 12.5% for a 2MB HugeTLB compared to the previous approach, which means 2GB per 1TB HugeTLB (2MB type). After the feature of "Free sonme vmemmap pages of HugeTLB page" is enabled, the mapping of the vmemmap addresses associated with a 2MB HugeTLB page becomes the figure below. HugeTLB struct pages(8 pages) page frame(8 pages) +-----------+ ---virt_to_page---> +-----------+ mapping to +-----------+---> PG_head | | | 0 | -------------> | 0 | | | +-----------+ +-----------+ | | | 1 | -------------> | 1 | | | +-----------+ +-----------+ | | | 2 | ----------------^ ^ ^ ^ ^ ^ | | +-----------+ | | | | | | | | 3 | ------------------+ | | | | | | +-----------+ | | | | | | | 4 | --------------------+ | | | | 2MB | +-----------+ | | | | | | 5 | ----------------------+ | | | | +-----------+ | | | | | 6 | ------------------------+ | | | +-----------+ | | | | 7 | --------------------------+ | | +-----------+ | | | | | | +-----------+ As we can see, the 2nd vmemmap page frame (indexed by 1) is reused and remaped. However, the 2nd vmemmap page frame is also can be freed to the buddy allocator, then we can change the mapping from the figure above to the figure below. HugeTLB struct pages(8 pages) page frame(8 pages) +-----------+ ---virt_to_page---> +-----------+ mapping to +-----------+---> PG_head | | | 0 | -------------> | 0 | | | +-----------+ +-----------+ | | | 1 | ---------------^ ^ ^ ^ ^ ^ ^ | | +-----------+ | | | | | | | | | 2 | -----------------+ | | | | | | | +-----------+ | | | | | | | | 3 | -------------------+ | | | | | | +-----------+ | | | | | | | 4 | ---------------------+ | | | | 2MB | +-----------+ | | | | | | 5 | -----------------------+ | | | | +-----------+ | | | | | 6 | -------------------------+ | | | +-----------+ | | | | 7 | ---------------------------+ | | +-----------+ | | | | | | +-----------+ After we do this, all tail vmemmap pages (1-7) are mapped to the head vmemmap page frame (0). In other words, there are more than one page struct with PG_head associated with each HugeTLB page. We __know__ that there is only one head page struct, the tail page structs with PG_head are fake head page structs. We need an approach to distinguish between those two different types of page structs so that compound_head(), PageHead() and PageTail() can work properly if the parameter is the tail page struct but with PG_head. The following code snippet describes how to distinguish between real and fake head page struct. if (test_bit(PG_head, &page->flags)) { unsigned long head = READ_ONCE(page[1].compound_head); if (head & 1) { if (head == (unsigned long)page + 1) ==> head page struct else ==> tail page struct } else ==> head page struct } We can safely access the field of the @page[1] with PG_head because the @page is a compound page composed with at least two contiguous pages. [songmuchun@bytedance.com: restore lost comment changes] Link: https://lkml.kernel.org/r/20211101031651.75851-1-songmuchun@bytedance.com Link: https://lkml.kernel.org/r/20211101031651.75851-2-songmuchun@bytedance.com Signed-off-by: Muchun Song Reviewed-by: Barry Song Cc: Mike Kravetz Cc: Oscar Salvador Cc: Michal Hocko Cc: David Hildenbrand Cc: Chen Huang Cc: Bodeddula Balasubramaniam Cc: Jonathan Corbet Cc: Matthew Wilcox Cc: Xiongchun Duan Cc: Fam Zheng Cc: Qi Zheng Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- Documentation/admin-guide/kernel-parameters.txt | 2 +- include/linux/page-flags.h | 78 +++++++++++++++++++++++-- mm/hugetlb_vmemmap.c | 62 +++++++++++--------- mm/sparse-vmemmap.c | 21 +++++++ 4 files changed, 130 insertions(+), 33 deletions(-) (limited to 'include/linux') diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index 7123524a86b8..bc39497f5788 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -1625,7 +1625,7 @@ [KNL] Reguires CONFIG_HUGETLB_PAGE_FREE_VMEMMAP enabled. Allows heavy hugetlb users to free up some more - memory (6 * PAGE_SIZE for each 2MB hugetlb page). + memory (7 * PAGE_SIZE for each 2MB hugetlb page). Format: { on | off (default) } on: enable the feature diff --git a/include/linux/page-flags.h b/include/linux/page-flags.h index 1c3b6e5c8bfd..111e453f23d2 100644 --- a/include/linux/page-flags.h +++ b/include/linux/page-flags.h @@ -190,13 +190,69 @@ enum pageflags { #ifndef __GENERATING_BOUNDS_H +#ifdef CONFIG_HUGETLB_PAGE_FREE_VMEMMAP +extern bool hugetlb_free_vmemmap_enabled; + +/* + * If the feature of freeing some vmemmap pages associated with each HugeTLB + * page is enabled, the head vmemmap page frame is reused and all of the tail + * vmemmap addresses map to the head vmemmap page frame (furture details can + * refer to the figure at the head of the mm/hugetlb_vmemmap.c). In other + * words, there are more than one page struct with PG_head associated with each + * HugeTLB page. We __know__ that there is only one head page struct, the tail + * page structs with PG_head are fake head page structs. We need an approach + * to distinguish between those two different types of page structs so that + * compound_head() can return the real head page struct when the parameter is + * the tail page struct but with PG_head. + * + * The page_fixed_fake_head() returns the real head page struct if the @page is + * fake page head, otherwise, returns @page which can either be a true page + * head or tail. + */ +static __always_inline const struct page *page_fixed_fake_head(const struct page *page) +{ + if (!hugetlb_free_vmemmap_enabled) + return page; + + /* + * Only addresses aligned with PAGE_SIZE of struct page may be fake head + * struct page. The alignment check aims to avoid access the fields ( + * e.g. compound_head) of the @page[1]. It can avoid touch a (possibly) + * cold cacheline in some cases. + */ + if (IS_ALIGNED((unsigned long)page, PAGE_SIZE) && + test_bit(PG_head, &page->flags)) { + /* + * We can safely access the field of the @page[1] with PG_head + * because the @page is a compound page composed with at least + * two contiguous pages. + */ + unsigned long head = READ_ONCE(page[1].compound_head); + + if (likely(head & 1)) + return (const struct page *)(head - 1); + } + return page; +} +#else +static inline const struct page *page_fixed_fake_head(const struct page *page) +{ + return page; +} +#endif + +static __always_inline int page_is_fake_head(struct page *page) +{ + return page_fixed_fake_head(page) != page; +} + static inline unsigned long _compound_head(const struct page *page) { unsigned long head = READ_ONCE(page->compound_head); if (unlikely(head & 1)) return head - 1; - return (unsigned long)page; + return (unsigned long)page_fixed_fake_head(page); } #define compound_head(page) ((typeof(page))_compound_head(page)) @@ -231,12 +287,13 @@ static inline unsigned long _compound_head(const struct page *page) static __always_inline int PageTail(struct page *page) { - return READ_ONCE(page->compound_head) & 1; + return READ_ONCE(page->compound_head) & 1 || page_is_fake_head(page); } static __always_inline int PageCompound(struct page *page) { - return test_bit(PG_head, &page->flags) || PageTail(page); + return test_bit(PG_head, &page->flags) || + READ_ONCE(page->compound_head) & 1; } #define PAGE_POISON_PATTERN -1l @@ -695,7 +752,20 @@ static inline bool test_set_page_writeback(struct page *page) return set_page_writeback(page); } -__PAGEFLAG(Head, head, PF_ANY) CLEARPAGEFLAG(Head, head, PF_ANY) +static __always_inline bool folio_test_head(struct folio *folio) +{ + return test_bit(PG_head, folio_flags(folio, FOLIO_PF_ANY)); +} + +static __always_inline int PageHead(struct page *page) +{ + PF_POISONED_CHECK(page); + return test_bit(PG_head, &page->flags) && !page_is_fake_head(page); +} + +__SETPAGEFLAG(Head, head, PF_ANY) +__CLEARPAGEFLAG(Head, head, PF_ANY) +CLEARPAGEFLAG(Head, head, PF_ANY) /** * folio_test_large() - Does this folio contain more than one page? diff --git a/mm/hugetlb_vmemmap.c b/mm/hugetlb_vmemmap.c index c540c21e26f5..4977f5a520c2 100644 --- a/mm/hugetlb_vmemmap.c +++ b/mm/hugetlb_vmemmap.c @@ -124,9 +124,9 @@ * page of page structs (page 0) associated with the HugeTLB page contains the 4 * page structs necessary to describe the HugeTLB. The only use of the remaining * pages of page structs (page 1 to page 7) is to point to page->compound_head. - * Therefore, we can remap pages 2 to 7 to page 1. Only 2 pages of page structs + * Therefore, we can remap pages 1 to 7 to page 0. Only 1 page of page structs * will be used for each HugeTLB page. This will allow us to free the remaining - * 6 pages to the buddy allocator. + * 7 pages to the buddy allocator. * * Here is how things look after remapping. * @@ -134,30 +134,30 @@ * +-----------+ ---virt_to_page---> +-----------+ mapping to +-----------+ * | | | 0 | -------------> | 0 | * | | +-----------+ +-----------+ - * | | | 1 | -------------> | 1 | - * | | +-----------+ +-----------+ - * | | | 2 | ----------------^ ^ ^ ^ ^ ^ - * | | +-----------+ | | | | | - * | | | 3 | ------------------+ | | | | - * | | +-----------+ | | | | - * | | | 4 | --------------------+ | | | - * | PMD | +-----------+ | | | - * | level | | 5 | ----------------------+ | | - * | mapping | +-----------+ | | - * | | | 6 | ------------------------+ | - * | | +-----------+ | - * | | | 7 | --------------------------+ + * | | | 1 | ---------------^ ^ ^ ^ ^ ^ ^ + * | | +-----------+ | | | | | | + * | | | 2 | -----------------+ | | | | | + * | | +-----------+ | | | | | + * | | | 3 | -------------------+ | | | | + * | | +-----------+ | | | | + * | | | 4 | ---------------------+ | | | + * | PMD | +-----------+ | | | + * | level | | 5 | -----------------------+ | | + * | mapping | +-----------+ | | + * | | | 6 | -------------------------+ | + * | | +-----------+ | + * | | | 7 | ---------------------------+ * | | +-----------+ * | | * | | * | | * +-----------+ * - * When a HugeTLB is freed to the buddy system, we should allocate 6 pages for + * When a HugeTLB is freed to the buddy system, we should allocate 7 pages for * vmemmap pages and restore the previous mapping relationship. * * For the HugeTLB page of the pud level mapping. It is similar to the former. - * We also can use this approach to free (PAGE_SIZE - 2) vmemmap pages. + * We also can use this approach to free (PAGE_SIZE - 1) vmemmap pages. * * Apart from the HugeTLB page of the pmd/pud level mapping, some architectures * (e.g. aarch64) provides a contiguous bit in the translation table entries @@ -166,7 +166,13 @@ * * The contiguous bit is used to increase the mapping size at the pmd and pte * (last) level. So this type of HugeTLB page can be optimized only when its - * size of the struct page structs is greater than 2 pages. + * size of the struct page structs is greater than 1 page. + * + * Notice: The head vmemmap page is not freed to the buddy allocator and all + * tail vmemmap pages are mapped to the head vmemmap page frame. So we can see + * more than one struct page struct with PG_head (e.g. 8 per 2 MB HugeTLB page) + * associated with each HugeTLB page. The compound_head() can handle this + * correctly (more details refer to the comment above compound_head()). */ #define pr_fmt(fmt) "HugeTLB: " fmt @@ -175,19 +181,21 @@ /* * There are a lot of struct page structures associated with each HugeTLB page. * For tail pages, the value of compound_head is the same. So we can reuse first - * page of tail page structures. We map the virtual addresses of the remaining - * pages of tail page structures to the first tail page struct, and then free - * these page frames. Therefore, we need to reserve two pages as vmemmap areas. + * page of head page structures. We map the virtual addresses of all the pages + * of tail page structures to the head page struct, and then free these page + * frames. Therefore, we need to reserve one pages as vmemmap areas. */ -#define RESERVE_VMEMMAP_NR 2U +#define RESERVE_VMEMMAP_NR 1U #define RESERVE_VMEMMAP_SIZE (RESERVE_VMEMMAP_NR << PAGE_SHIFT) -bool hugetlb_free_vmemmap_enabled = IS_ENABLED(CONFIG_HUGETLB_PAGE_FREE_VMEMMAP_DEFAULT_ON); +bool hugetlb_free_vmemmap_enabled __read_mostly = + IS_ENABLED(CONFIG_HUGETLB_PAGE_FREE_VMEMMAP_DEFAULT_ON); +EXPORT_SYMBOL(hugetlb_free_vmemmap_enabled); static int __init early_hugetlb_free_vmemmap_param(char *buf) { /* We cannot optimize if a "struct page" crosses page boundaries. */ - if ((!is_power_of_2(sizeof(struct page)))) { + if (!is_power_of_2(sizeof(struct page))) { pr_warn("cannot free vmemmap pages because \"struct page\" crosses page boundaries\n"); return 0; } @@ -236,7 +244,6 @@ int alloc_huge_page_vmemmap(struct hstate *h, struct page *head) */ ret = vmemmap_remap_alloc(vmemmap_addr, vmemmap_end, vmemmap_reuse, GFP_KERNEL | __GFP_NORETRY | __GFP_THISNODE); - if (!ret) ClearHPageVmemmapOptimized(head); @@ -282,9 +289,8 @@ void __init hugetlb_vmemmap_init(struct hstate *h) vmemmap_pages = (nr_pages * sizeof(struct page)) >> PAGE_SHIFT; /* - * The head page and the first tail page are not to be freed to buddy - * allocator, the other pages will map to the first tail page, so they - * can be freed. + * The head page is not to be freed to buddy allocator, the other tail + * pages will map to the head page, so they can be freed. * * Could RESERVE_VMEMMAP_NR be greater than @vmemmap_pages? It is true * on some architectures (e.g. aarch64). See Documentation/arm64/ diff --git a/mm/sparse-vmemmap.c b/mm/sparse-vmemmap.c index db6df27c852a..e881f5db7091 100644 --- a/mm/sparse-vmemmap.c +++ b/mm/sparse-vmemmap.c @@ -245,6 +245,26 @@ static void vmemmap_remap_pte(pte_t *pte, unsigned long addr, set_pte_at(&init_mm, addr, pte, entry); } +/* + * How many struct page structs need to be reset. When we reuse the head + * struct page, the special metadata (e.g. page->flags or page->mapping) + * cannot copy to the tail struct page structs. The invalid value will be + * checked in the free_tail_pages_check(). In order to avoid the message + * of "corrupted mapping in tail page". We need to reset at least 3 (one + * head struct page struct and two tail struct page structs) struct page + * structs. + */ +#define NR_RESET_STRUCT_PAGE 3 + +static inline void reset_struct_pages(struct page *start) +{ + int i; + struct page *from = start + NR_RESET_STRUCT_PAGE; + + for (i = 0; i < NR_RESET_STRUCT_PAGE; i++) + memcpy(start + i, from, sizeof(*from)); +} + static void vmemmap_restore_pte(pte_t *pte, unsigned long addr, struct vmemmap_remap_walk *walk) { @@ -258,6 +278,7 @@ static void vmemmap_restore_pte(pte_t *pte, unsigned long addr, list_del(&page->lru); to = page_to_virt(page); copy_page(to, (void *)walk->reuse_addr); + reset_struct_pages(to); set_pte_at(&init_mm, addr, pte, mk_pte(page, pgprot)); } -- cgit v1.2.3 From a6b40850c442bf996e729e1d441d3dbc37cea171 Mon Sep 17 00:00:00 2001 From: Muchun Song Date: Tue, 22 Mar 2022 14:45:03 -0700 Subject: mm: hugetlb: replace hugetlb_free_vmemmap_enabled with a static_key The page_fixed_fake_head() is used throughout memory management and the conditional check requires checking a global variable, although the overhead of this check may be small, it increases when the memory cache comes under pressure. Also, the global variable will not be modified after system boot, so it is very appropriate to use static key machanism. Link: https://lkml.kernel.org/r/20211101031651.75851-3-songmuchun@bytedance.com Signed-off-by: Muchun Song Reviewed-by: Barry Song Cc: Bodeddula Balasubramaniam Cc: Chen Huang Cc: David Hildenbrand Cc: Fam Zheng Cc: Jonathan Corbet Cc: Matthew Wilcox Cc: Michal Hocko Cc: Mike Kravetz Cc: Oscar Salvador Cc: Qi Zheng Cc: Xiongchun Duan Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/hugetlb.h | 6 ------ include/linux/page-flags.h | 16 ++++++++++++++-- mm/hugetlb_vmemmap.c | 12 ++++++------ mm/memory_hotplug.c | 2 +- 4 files changed, 21 insertions(+), 15 deletions(-) (limited to 'include/linux') diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h index 52c462390aee..08357b4c7be7 100644 --- a/include/linux/hugetlb.h +++ b/include/linux/hugetlb.h @@ -1075,12 +1075,6 @@ static inline void set_huge_swap_pte_at(struct mm_struct *mm, unsigned long addr } #endif /* CONFIG_HUGETLB_PAGE */ -#ifdef CONFIG_HUGETLB_PAGE_FREE_VMEMMAP -extern bool hugetlb_free_vmemmap_enabled; -#else -#define hugetlb_free_vmemmap_enabled false -#endif - static inline spinlock_t *huge_pte_lock(struct hstate *h, struct mm_struct *mm, pte_t *pte) { diff --git a/include/linux/page-flags.h b/include/linux/page-flags.h index 111e453f23d2..340cb8156568 100644 --- a/include/linux/page-flags.h +++ b/include/linux/page-flags.h @@ -191,7 +191,14 @@ enum pageflags { #ifndef __GENERATING_BOUNDS_H #ifdef CONFIG_HUGETLB_PAGE_FREE_VMEMMAP -extern bool hugetlb_free_vmemmap_enabled; +DECLARE_STATIC_KEY_MAYBE(CONFIG_HUGETLB_PAGE_FREE_VMEMMAP_DEFAULT_ON, + hugetlb_free_vmemmap_enabled_key); + +static __always_inline bool hugetlb_free_vmemmap_enabled(void) +{ + return static_branch_maybe(CONFIG_HUGETLB_PAGE_FREE_VMEMMAP_DEFAULT_ON, + &hugetlb_free_vmemmap_enabled_key); +} /* * If the feature of freeing some vmemmap pages associated with each HugeTLB @@ -211,7 +218,7 @@ extern bool hugetlb_free_vmemmap_enabled; */ static __always_inline const struct page *page_fixed_fake_head(const struct page *page) { - if (!hugetlb_free_vmemmap_enabled) + if (!hugetlb_free_vmemmap_enabled()) return page; /* @@ -239,6 +246,11 @@ static inline const struct page *page_fixed_fake_head(const struct page *page) { return page; } + +static inline bool hugetlb_free_vmemmap_enabled(void) +{ + return false; +} #endif static __always_inline int page_is_fake_head(struct page *page) diff --git a/mm/hugetlb_vmemmap.c b/mm/hugetlb_vmemmap.c index 4977f5a520c2..791626983c2e 100644 --- a/mm/hugetlb_vmemmap.c +++ b/mm/hugetlb_vmemmap.c @@ -188,9 +188,9 @@ #define RESERVE_VMEMMAP_NR 1U #define RESERVE_VMEMMAP_SIZE (RESERVE_VMEMMAP_NR << PAGE_SHIFT) -bool hugetlb_free_vmemmap_enabled __read_mostly = - IS_ENABLED(CONFIG_HUGETLB_PAGE_FREE_VMEMMAP_DEFAULT_ON); -EXPORT_SYMBOL(hugetlb_free_vmemmap_enabled); +DEFINE_STATIC_KEY_MAYBE(CONFIG_HUGETLB_PAGE_FREE_VMEMMAP_DEFAULT_ON, + hugetlb_free_vmemmap_enabled_key); +EXPORT_SYMBOL(hugetlb_free_vmemmap_enabled_key); static int __init early_hugetlb_free_vmemmap_param(char *buf) { @@ -204,9 +204,9 @@ static int __init early_hugetlb_free_vmemmap_param(char *buf) return -EINVAL; if (!strcmp(buf, "on")) - hugetlb_free_vmemmap_enabled = true; + static_branch_enable(&hugetlb_free_vmemmap_enabled_key); else if (!strcmp(buf, "off")) - hugetlb_free_vmemmap_enabled = false; + static_branch_disable(&hugetlb_free_vmemmap_enabled_key); else return -EINVAL; @@ -284,7 +284,7 @@ void __init hugetlb_vmemmap_init(struct hstate *h) BUILD_BUG_ON(__NR_USED_SUBPAGE >= RESERVE_VMEMMAP_SIZE / sizeof(struct page)); - if (!hugetlb_free_vmemmap_enabled) + if (!hugetlb_free_vmemmap_enabled()) return; vmemmap_pages = (nr_pages * sizeof(struct page)) >> PAGE_SHIFT; diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index 2a9627dc784c..0139b77c51d5 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -1327,7 +1327,7 @@ bool mhp_supports_memmap_on_memory(unsigned long size) * populate a single PMD. */ return memmap_on_memory && - !hugetlb_free_vmemmap_enabled && + !hugetlb_free_vmemmap_enabled() && IS_ENABLED(CONFIG_MHP_MEMMAP_ON_MEMORY) && size == memory_block_size_bytes() && IS_ALIGNED(vmemmap_size, PMD_SIZE) && -- cgit v1.2.3 From e54084173487804f5e2f23facf107fd9336e637e Mon Sep 17 00:00:00 2001 From: Muchun Song Date: Tue, 22 Mar 2022 14:45:12 -0700 Subject: mm: sparsemem: move vmemmap related to HugeTLB to CONFIG_HUGETLB_PAGE_FREE_VMEMMAP The vmemmap_remap_free/alloc are relevant to HugeTLB, so move those functiongs to the scope of CONFIG_HUGETLB_PAGE_FREE_VMEMMAP. Link: https://lkml.kernel.org/r/20211101031651.75851-6-songmuchun@bytedance.com Signed-off-by: Muchun Song Reviewed-by: Barry Song Cc: Bodeddula Balasubramaniam Cc: Chen Huang Cc: David Hildenbrand Cc: Fam Zheng Cc: Jonathan Corbet Cc: Matthew Wilcox Cc: Michal Hocko Cc: Mike Kravetz Cc: Oscar Salvador Cc: Qi Zheng Cc: Xiongchun Duan Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/mm.h | 2 ++ mm/sparse-vmemmap.c | 2 ++ 2 files changed, 4 insertions(+) (limited to 'include/linux') diff --git a/include/linux/mm.h b/include/linux/mm.h index 45a449e8c209..9d58321386cc 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -3146,10 +3146,12 @@ static inline void print_vma_addr(char *prefix, unsigned long rip) } #endif +#ifdef CONFIG_HUGETLB_PAGE_FREE_VMEMMAP int vmemmap_remap_free(unsigned long start, unsigned long end, unsigned long reuse); int vmemmap_remap_alloc(unsigned long start, unsigned long end, unsigned long reuse, gfp_t gfp_mask); +#endif void *sparse_buffer_alloc(unsigned long size); struct page * __populate_section_memmap(unsigned long pfn, diff --git a/mm/sparse-vmemmap.c b/mm/sparse-vmemmap.c index c64d1aa3c4b5..8aecd6b3896c 100644 --- a/mm/sparse-vmemmap.c +++ b/mm/sparse-vmemmap.c @@ -34,6 +34,7 @@ #include #include +#ifdef CONFIG_HUGETLB_PAGE_FREE_VMEMMAP /** * struct vmemmap_remap_walk - walk vmemmap page table * @@ -419,6 +420,7 @@ int vmemmap_remap_alloc(unsigned long start, unsigned long end, return 0; } +#endif /* CONFIG_HUGETLB_PAGE_FREE_VMEMMAP */ /* * Allocate a block of memory to be used to back the virtual memory map -- cgit v1.2.3 From 824ddc601adc2cc48efb7f58b57997986c1c1276 Mon Sep 17 00:00:00 2001 From: Nadav Amit Date: Tue, 22 Mar 2022 14:45:32 -0700 Subject: userfaultfd: provide unmasked address on page-fault Userfaultfd is supposed to provide the full address (i.e., unmasked) of the faulting access back to userspace. However, that is not the case for quite some time. Even running "userfaultfd_demo" from the userfaultfd man page provides the wrong output (and contradicts the man page). Notice that "UFFD_EVENT_PAGEFAULT event" shows the masked address (7fc5e30b3000) and not the first read address (0x7fc5e30b300f). Address returned by mmap() = 0x7fc5e30b3000 fault_handler_thread(): poll() returns: nready = 1; POLLIN = 1; POLLERR = 0 UFFD_EVENT_PAGEFAULT event: flags = 0; address = 7fc5e30b3000 (uffdio_copy.copy returned 4096) Read address 0x7fc5e30b300f in main(): A Read address 0x7fc5e30b340f in main(): A Read address 0x7fc5e30b380f in main(): A Read address 0x7fc5e30b3c0f in main(): A The exact address is useful for various reasons and specifically for prefetching decisions. If it is known that the memory is populated by certain objects whose size is not page-aligned, then based on the faulting address, the uffd-monitor can decide whether to prefetch and prefault the adjacent page. This bug has been for quite some time in the kernel: since commit 1a29d85eb0f1 ("mm: use vmf->address instead of of vmf->virtual_address") vmf->virtual_address"), which dates back to 2016. A concern has been raised that existing userspace application might rely on the old/wrong behavior in which the address is masked. Therefore, it was suggested to provide the masked address unless the user explicitly asks for the exact address. Add a new userfaultfd feature UFFD_FEATURE_EXACT_ADDRESS to direct userfaultfd to provide the exact address. Add a new "real_address" field to vmf to hold the unmasked address. Provide the address to userspace accordingly. Initialize real_address in various code-paths to be consistent with address, even when it is not used, to be on the safe side. [namit@vmware.com: initialize real_address on all code paths, per Jan] Link: https://lkml.kernel.org/r/20220226022655.350562-1-namit@vmware.com [akpm@linux-foundation.org: fix typo in comment, per Jan] Link: https://lkml.kernel.org/r/20220218041003.3508-1-namit@vmware.com Signed-off-by: Nadav Amit Acked-by: Peter Xu Reviewed-by: David Hildenbrand Acked-by: Mike Rapoport Reviewed-by: Jan Kara Cc: Andrea Arcangeli Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/userfaultfd.c | 5 ++++- include/linux/mm.h | 3 ++- include/uapi/linux/userfaultfd.h | 8 +++++++- mm/hugetlb.c | 6 ++++-- mm/memory.c | 1 + mm/swapfile.c | 1 + 6 files changed, 19 insertions(+), 5 deletions(-) (limited to 'include/linux') diff --git a/fs/userfaultfd.c b/fs/userfaultfd.c index 8e03b3d3f5fa..aa0c47cb0d16 100644 --- a/fs/userfaultfd.c +++ b/fs/userfaultfd.c @@ -198,6 +198,9 @@ static inline struct uffd_msg userfault_msg(unsigned long address, struct uffd_msg msg; msg_init(&msg); msg.event = UFFD_EVENT_PAGEFAULT; + + if (!(features & UFFD_FEATURE_EXACT_ADDRESS)) + address &= PAGE_MASK; msg.arg.pagefault.address = address; /* * These flags indicate why the userfault occurred: @@ -482,7 +485,7 @@ vm_fault_t handle_userfault(struct vm_fault *vmf, unsigned long reason) init_waitqueue_func_entry(&uwq.wq, userfaultfd_wake_function); uwq.wq.private = current; - uwq.msg = userfault_msg(vmf->address, vmf->flags, reason, + uwq.msg = userfault_msg(vmf->real_address, vmf->flags, reason, ctx->features); uwq.ctx = ctx; uwq.waken = false; diff --git a/include/linux/mm.h b/include/linux/mm.h index 9d58321386cc..0e4fd101616e 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -478,7 +478,8 @@ struct vm_fault { struct vm_area_struct *vma; /* Target VMA */ gfp_t gfp_mask; /* gfp mask to be used for allocations */ pgoff_t pgoff; /* Logical page offset based on vma */ - unsigned long address; /* Faulting virtual address */ + unsigned long address; /* Faulting virtual address - masked */ + unsigned long real_address; /* Faulting virtual address - unmasked */ }; enum fault_flag flags; /* FAULT_FLAG_xxx flags * XXX: should really be 'const' */ diff --git a/include/uapi/linux/userfaultfd.h b/include/uapi/linux/userfaultfd.h index 05b31d60acf6..ef739054cb1c 100644 --- a/include/uapi/linux/userfaultfd.h +++ b/include/uapi/linux/userfaultfd.h @@ -32,7 +32,8 @@ UFFD_FEATURE_SIGBUS | \ UFFD_FEATURE_THREAD_ID | \ UFFD_FEATURE_MINOR_HUGETLBFS | \ - UFFD_FEATURE_MINOR_SHMEM) + UFFD_FEATURE_MINOR_SHMEM | \ + UFFD_FEATURE_EXACT_ADDRESS) #define UFFD_API_IOCTLS \ ((__u64)1 << _UFFDIO_REGISTER | \ (__u64)1 << _UFFDIO_UNREGISTER | \ @@ -189,6 +190,10 @@ struct uffdio_api { * * UFFD_FEATURE_MINOR_SHMEM indicates the same support as * UFFD_FEATURE_MINOR_HUGETLBFS, but for shmem-backed pages instead. + * + * UFFD_FEATURE_EXACT_ADDRESS indicates that the exact address of page + * faults would be provided and the offset within the page would not be + * masked. */ #define UFFD_FEATURE_PAGEFAULT_FLAG_WP (1<<0) #define UFFD_FEATURE_EVENT_FORK (1<<1) @@ -201,6 +206,7 @@ struct uffdio_api { #define UFFD_FEATURE_THREAD_ID (1<<8) #define UFFD_FEATURE_MINOR_HUGETLBFS (1<<9) #define UFFD_FEATURE_MINOR_SHMEM (1<<10) +#define UFFD_FEATURE_EXACT_ADDRESS (1<<11) __u64 features; __u64 ioctls; diff --git a/mm/hugetlb.c b/mm/hugetlb.c index f425147e4ce3..75b41879e9e9 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -5341,6 +5341,7 @@ static inline vm_fault_t hugetlb_handle_userfault(struct vm_area_struct *vma, pgoff_t idx, unsigned int flags, unsigned long haddr, + unsigned long addr, unsigned long reason) { vm_fault_t ret; @@ -5348,6 +5349,7 @@ static inline vm_fault_t hugetlb_handle_userfault(struct vm_area_struct *vma, struct vm_fault vmf = { .vma = vma, .address = haddr, + .real_address = addr, .flags = flags, /* @@ -5416,7 +5418,7 @@ retry: /* Check for page in userfault range */ if (userfaultfd_missing(vma)) { ret = hugetlb_handle_userfault(vma, mapping, idx, - flags, haddr, + flags, haddr, address, VM_UFFD_MISSING); goto out; } @@ -5480,7 +5482,7 @@ retry: unlock_page(page); put_page(page); ret = hugetlb_handle_userfault(vma, mapping, idx, - flags, haddr, + flags, haddr, address, VM_UFFD_MINOR); goto out; } diff --git a/mm/memory.c b/mm/memory.c index 1a55b4c5b5db..e0f3410fa70c 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -4633,6 +4633,7 @@ static vm_fault_t __handle_mm_fault(struct vm_area_struct *vma, struct vm_fault vmf = { .vma = vma, .address = address & PAGE_MASK, + .real_address = address, .flags = flags, .pgoff = linear_page_index(vma, address), .gfp_mask = __get_fault_gfp_mask(vma), diff --git a/mm/swapfile.c b/mm/swapfile.c index bf0df7aa7158..33c7abb16610 100644 --- a/mm/swapfile.c +++ b/mm/swapfile.c @@ -1951,6 +1951,7 @@ static int unuse_pte_range(struct vm_area_struct *vma, pmd_t *pmd, struct vm_fault vmf = { .vma = vma, .address = addr, + .real_address = addr, .pmd = pmd, }; -- cgit v1.2.3 From b698f0a1773f7df73f2bb4bfe0e597ea1bb3881f Mon Sep 17 00:00:00 2001 From: Hugh Dickins Date: Tue, 22 Mar 2022 14:45:38 -0700 Subject: mm/fs: delete PF_SWAPWRITE PF_SWAPWRITE has been redundant since v3.2 commit ee72886d8ed5 ("mm: vmscan: do not writeback filesystem pages in direct reclaim"). Coincidentally, NeilBrown's current patch "remove inode_congested()" deletes may_write_to_inode(), which appeared to be the one function which took notice of PF_SWAPWRITE. But if you study the old logic, and the conditions under which may_write_to_inode() was called, you discover that flag and function have been pointless for a decade. Link: https://lkml.kernel.org/r/75e80e7-742d-e3bd-531-614db8961e4@google.com Signed-off-by: Hugh Dickins Cc: NeilBrown Cc: Jan Kara Cc: "Darrick J. Wong" Cc: Dave Chinner Cc: Matthew Wilcox Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/fs-writeback.c | 3 --- fs/xfs/libxfs/xfs_btree.c | 2 +- include/linux/sched.h | 1 - mm/migrate.c | 7 ------- mm/vmscan.c | 8 ++------ 5 files changed, 3 insertions(+), 18 deletions(-) (limited to 'include/linux') diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c index 42a3dfad40b8..3d8dacfff150 100644 --- a/fs/fs-writeback.c +++ b/fs/fs-writeback.c @@ -2197,7 +2197,6 @@ void wb_workfn(struct work_struct *work) long pages_written; set_worker_desc("flush-%s", bdi_dev_name(wb->bdi)); - current->flags |= PF_SWAPWRITE; if (likely(!current_is_workqueue_rescuer() || !test_bit(WB_registered, &wb->state))) { @@ -2226,8 +2225,6 @@ void wb_workfn(struct work_struct *work) wb_wakeup(wb); else if (wb_has_dirty_io(wb) && dirty_writeback_interval) wb_wakeup_delayed(wb); - - current->flags &= ~PF_SWAPWRITE; } /* diff --git a/fs/xfs/libxfs/xfs_btree.c b/fs/xfs/libxfs/xfs_btree.c index f18a875f51c6..c1500b238520 100644 --- a/fs/xfs/libxfs/xfs_btree.c +++ b/fs/xfs/libxfs/xfs_btree.c @@ -2818,7 +2818,7 @@ xfs_btree_split_worker( * in any way. */ if (args->kswapd) - new_pflags |= PF_MEMALLOC | PF_SWAPWRITE | PF_KSWAPD; + new_pflags |= PF_MEMALLOC | PF_KSWAPD; current_set_flags_nested(&pflags, new_pflags); xfs_trans_set_context(args->cur->bc_tp); diff --git a/include/linux/sched.h b/include/linux/sched.h index 75ba8aa60248..c3c841a02a00 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -1689,7 +1689,6 @@ extern struct pid *cad_pid; * I am cleaning dirty pages from some other bdi. */ #define PF_KTHREAD 0x00200000 /* I am a kernel thread */ #define PF_RANDOMIZE 0x00400000 /* Randomize virtual address space */ -#define PF_SWAPWRITE 0x00800000 /* Allowed to write to swap */ #define PF_NO_SETAFFINITY 0x04000000 /* Userland is not allowed to meddle with cpus_mask */ #define PF_MCE_EARLY 0x08000000 /* Early kill for mce process policy */ #define PF_MEMALLOC_PIN 0x10000000 /* Allocation context constrained to zones which allow long term pinning. */ diff --git a/mm/migrate.c b/mm/migrate.c index 4359d49b508a..fc75c409482e 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -1350,7 +1350,6 @@ int migrate_pages(struct list_head *from, new_page_t get_new_page, bool is_thp = false; struct page *page; struct page *page2; - int swapwrite = current->flags & PF_SWAPWRITE; int rc, nr_subpages; LIST_HEAD(ret_pages); LIST_HEAD(thp_split_pages); @@ -1359,9 +1358,6 @@ int migrate_pages(struct list_head *from, new_page_t get_new_page, trace_mm_migrate_pages_start(mode, reason); - if (!swapwrite) - current->flags |= PF_SWAPWRITE; - thp_subpage_migration: for (pass = 0; pass < 10 && (retry || thp_retry); pass++) { retry = 0; @@ -1516,9 +1512,6 @@ out: trace_mm_migrate_pages(nr_succeeded, nr_failed_pages, nr_thp_succeeded, nr_thp_failed, nr_thp_split, mode, reason); - if (!swapwrite) - current->flags &= ~PF_SWAPWRITE; - if (ret_succeeded) *ret_succeeded = nr_succeeded; diff --git a/mm/vmscan.c b/mm/vmscan.c index 5e1469887afa..d4168966311f 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -4457,7 +4457,7 @@ static int kswapd(void *p) * us from recursively trying to free more memory as we're * trying to free the first piece of memory in the first place). */ - tsk->flags |= PF_MEMALLOC | PF_SWAPWRITE | PF_KSWAPD; + tsk->flags |= PF_MEMALLOC | PF_KSWAPD; set_freezable(); WRITE_ONCE(pgdat->kswapd_order, 0); @@ -4508,7 +4508,7 @@ kswapd_try_sleep: goto kswapd_try_sleep; } - tsk->flags &= ~(PF_MEMALLOC | PF_SWAPWRITE | PF_KSWAPD); + tsk->flags &= ~(PF_MEMALLOC | PF_KSWAPD); return 0; } @@ -4749,11 +4749,8 @@ static int __node_reclaim(struct pglist_data *pgdat, gfp_t gfp_mask, unsigned in fs_reclaim_acquire(sc.gfp_mask); /* * We need to be able to allocate from the reserves for RECLAIM_UNMAP - * and we also need to be able to write out pages for RECLAIM_WRITE - * and RECLAIM_UNMAP. */ noreclaim_flag = memalloc_noreclaim_save(); - p->flags |= PF_SWAPWRITE; set_task_reclaim_state(p, &sc.reclaim_state); if (node_pagecache_reclaimable(pgdat) > pgdat->min_unmapped_pages) { @@ -4767,7 +4764,6 @@ static int __node_reclaim(struct pglist_data *pgdat, gfp_t gfp_mask, unsigned in } set_task_reclaim_state(p, NULL); - current->flags &= ~PF_SWAPWRITE; memalloc_noreclaim_restore(noreclaim_flag); fs_reclaim_release(sc.gfp_mask); psi_memstall_leave(&pflags); -- cgit v1.2.3 From 89f6c88a6ab4a11deb14c270f7f1454cda4f73d6 Mon Sep 17 00:00:00 2001 From: Hugh Dickins Date: Tue, 22 Mar 2022 14:45:41 -0700 Subject: mm: __isolate_lru_page_prepare() in isolate_migratepages_block() __isolate_lru_page_prepare() conflates two unrelated functions, with the flags to one disjoint from the flags to the other; and hides some of the important checks outside of isolate_migratepages_block(), where the sequence is better to be visible. It comes from the days of lumpy reclaim, before compaction, when the combination made more sense. Move what's needed by mm/compaction.c isolate_migratepages_block() inline there, and what's needed by mm/vmscan.c isolate_lru_pages() inline there. Shorten "isolate_mode" to "mode", so the sequence of conditions is easier to read. Declare a "mapping" variable, to save one call to page_mapping() (but not another: calling again after page is locked is necessary). Simplify isolate_lru_pages() with a "move_to" list pointer. Link: https://lkml.kernel.org/r/879d62a8-91cc-d3c6-fb3b-69768236df68@google.com Signed-off-by: Hugh Dickins Acked-by: David Rientjes Reviewed-by: Alex Shi Cc: Alexander Duyck Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/swap.h | 1 - mm/compaction.c | 51 ++++++++++++++++++++++---- mm/vmscan.c | 101 +++++++++------------------------------------------ 3 files changed, 62 insertions(+), 91 deletions(-) (limited to 'include/linux') diff --git a/include/linux/swap.h b/include/linux/swap.h index 3db431276d82..a246c137678e 100644 --- a/include/linux/swap.h +++ b/include/linux/swap.h @@ -387,7 +387,6 @@ extern void lru_cache_add_inactive_or_unevictable(struct page *page, extern unsigned long zone_reclaimable_pages(struct zone *zone); extern unsigned long try_to_free_pages(struct zonelist *zonelist, int order, gfp_t gfp_mask, nodemask_t *mask); -extern bool __isolate_lru_page_prepare(struct page *page, isolate_mode_t mode); extern unsigned long try_to_free_mem_cgroup_pages(struct mem_cgroup *memcg, unsigned long nr_pages, gfp_t gfp_mask, diff --git a/mm/compaction.c b/mm/compaction.c index b4e94cda3019..b72fb9da4c45 100644 --- a/mm/compaction.c +++ b/mm/compaction.c @@ -785,7 +785,7 @@ static bool too_many_isolated(pg_data_t *pgdat) * @cc: Compaction control structure. * @low_pfn: The first PFN to isolate * @end_pfn: The one-past-the-last PFN to isolate, within same pageblock - * @isolate_mode: Isolation mode to be used. + * @mode: Isolation mode to be used. * * Isolate all pages that can be migrated from the range specified by * [low_pfn, end_pfn). The range is expected to be within same pageblock. @@ -798,7 +798,7 @@ static bool too_many_isolated(pg_data_t *pgdat) */ static int isolate_migratepages_block(struct compact_control *cc, unsigned long low_pfn, - unsigned long end_pfn, isolate_mode_t isolate_mode) + unsigned long end_pfn, isolate_mode_t mode) { pg_data_t *pgdat = cc->zone->zone_pgdat; unsigned long nr_scanned = 0, nr_isolated = 0; @@ -806,6 +806,7 @@ isolate_migratepages_block(struct compact_control *cc, unsigned long low_pfn, unsigned long flags = 0; struct lruvec *locked = NULL; struct page *page = NULL, *valid_page = NULL; + struct address_space *mapping; unsigned long start_pfn = low_pfn; bool skip_on_failure = false; unsigned long next_skip_pfn = 0; @@ -990,7 +991,7 @@ isolate_migratepages_block(struct compact_control *cc, unsigned long low_pfn, locked = NULL; } - if (!isolate_movable_page(page, isolate_mode)) + if (!isolate_movable_page(page, mode)) goto isolate_success; } @@ -1002,15 +1003,15 @@ isolate_migratepages_block(struct compact_control *cc, unsigned long low_pfn, * so avoid taking lru_lock and isolating it unnecessarily in an * admittedly racy check. */ - if (!page_mapping(page) && - page_count(page) > page_mapcount(page)) + mapping = page_mapping(page); + if (!mapping && page_count(page) > page_mapcount(page)) goto isolate_fail; /* * Only allow to migrate anonymous pages in GFP_NOFS context * because those do not depend on fs locks. */ - if (!(cc->gfp_mask & __GFP_FS) && page_mapping(page)) + if (!(cc->gfp_mask & __GFP_FS) && mapping) goto isolate_fail; /* @@ -1021,9 +1022,45 @@ isolate_migratepages_block(struct compact_control *cc, unsigned long low_pfn, if (unlikely(!get_page_unless_zero(page))) goto isolate_fail; - if (!__isolate_lru_page_prepare(page, isolate_mode)) + /* Only take pages on LRU: a check now makes later tests safe */ + if (!PageLRU(page)) + goto isolate_fail_put; + + /* Compaction might skip unevictable pages but CMA takes them */ + if (!(mode & ISOLATE_UNEVICTABLE) && PageUnevictable(page)) + goto isolate_fail_put; + + /* + * To minimise LRU disruption, the caller can indicate with + * ISOLATE_ASYNC_MIGRATE that it only wants to isolate pages + * it will be able to migrate without blocking - clean pages + * for the most part. PageWriteback would require blocking. + */ + if ((mode & ISOLATE_ASYNC_MIGRATE) && PageWriteback(page)) goto isolate_fail_put; + if ((mode & ISOLATE_ASYNC_MIGRATE) && PageDirty(page)) { + bool migrate_dirty; + + /* + * Only pages without mappings or that have a + * ->migratepage callback are possible to migrate + * without blocking. However, we can be racing with + * truncation so it's necessary to lock the page + * to stabilise the mapping as truncation holds + * the page lock until after the page is removed + * from the page cache. + */ + if (!trylock_page(page)) + goto isolate_fail_put; + + mapping = page_mapping(page); + migrate_dirty = !mapping || mapping->a_ops->migratepage; + unlock_page(page); + if (!migrate_dirty) + goto isolate_fail_put; + } + /* Try isolate the page */ if (!TestClearPageLRU(page)) goto isolate_fail_put; diff --git a/mm/vmscan.c b/mm/vmscan.c index d4168966311f..24601f394c25 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -1998,69 +1998,6 @@ unsigned int reclaim_clean_pages_from_list(struct zone *zone, return nr_reclaimed; } -/* - * Attempt to remove the specified page from its LRU. Only take this page - * if it is of the appropriate PageActive status. Pages which are being - * freed elsewhere are also ignored. - * - * page: page to consider - * mode: one of the LRU isolation modes defined above - * - * returns true on success, false on failure. - */ -bool __isolate_lru_page_prepare(struct page *page, isolate_mode_t mode) -{ - /* Only take pages on the LRU. */ - if (!PageLRU(page)) - return false; - - /* Compaction should not handle unevictable pages but CMA can do so */ - if (PageUnevictable(page) && !(mode & ISOLATE_UNEVICTABLE)) - return false; - - /* - * To minimise LRU disruption, the caller can indicate that it only - * wants to isolate pages it will be able to operate on without - * blocking - clean pages for the most part. - * - * ISOLATE_ASYNC_MIGRATE is used to indicate that it only wants to pages - * that it is possible to migrate without blocking - */ - if (mode & ISOLATE_ASYNC_MIGRATE) { - /* All the caller can do on PageWriteback is block */ - if (PageWriteback(page)) - return false; - - if (PageDirty(page)) { - struct address_space *mapping; - bool migrate_dirty; - - /* - * Only pages without mappings or that have a - * ->migratepage callback are possible to migrate - * without blocking. However, we can be racing with - * truncation so it's necessary to lock the page - * to stabilise the mapping as truncation holds - * the page lock until after the page is removed - * from the page cache. - */ - if (!trylock_page(page)) - return false; - - mapping = page_mapping(page); - migrate_dirty = !mapping || mapping->a_ops->migratepage; - unlock_page(page); - if (!migrate_dirty) - return false; - } - } - - if ((mode & ISOLATE_UNMAPPED) && page_mapped(page)) - return false; - - return true; -} - /* * Update LRU sizes after isolating pages. The LRU size updates must * be complete before mem_cgroup_update_lru_size due to a sanity check. @@ -2112,11 +2049,11 @@ static unsigned long isolate_lru_pages(unsigned long nr_to_scan, unsigned long skipped = 0; unsigned long scan, total_scan, nr_pages; LIST_HEAD(pages_skipped); - isolate_mode_t mode = (sc->may_unmap ? 0 : ISOLATE_UNMAPPED); total_scan = 0; scan = 0; while (scan < nr_to_scan && !list_empty(src)) { + struct list_head *move_to = src; struct page *page; page = lru_to_page(src); @@ -2126,9 +2063,9 @@ static unsigned long isolate_lru_pages(unsigned long nr_to_scan, total_scan += nr_pages; if (page_zonenum(page) > sc->reclaim_idx) { - list_move(&page->lru, &pages_skipped); nr_skipped[page_zonenum(page)] += nr_pages; - continue; + move_to = &pages_skipped; + goto move; } /* @@ -2136,37 +2073,34 @@ static unsigned long isolate_lru_pages(unsigned long nr_to_scan, * return with no isolated pages if the LRU mostly contains * ineligible pages. This causes the VM to not reclaim any * pages, triggering a premature OOM. - * - * Account all tail pages of THP. This would not cause - * premature OOM since __isolate_lru_page() returns -EBUSY - * only when the page is being freed somewhere else. + * Account all tail pages of THP. */ scan += nr_pages; - if (!__isolate_lru_page_prepare(page, mode)) { - /* It is being freed elsewhere */ - list_move(&page->lru, src); - continue; - } + + if (!PageLRU(page)) + goto move; + if (!sc->may_unmap && page_mapped(page)) + goto move; + /* * Be careful not to clear PageLRU until after we're * sure the page is not being freed elsewhere -- the * page release code relies on it. */ - if (unlikely(!get_page_unless_zero(page))) { - list_move(&page->lru, src); - continue; - } + if (unlikely(!get_page_unless_zero(page))) + goto move; if (!TestClearPageLRU(page)) { /* Another thread is already isolating this page */ put_page(page); - list_move(&page->lru, src); - continue; + goto move; } nr_taken += nr_pages; nr_zone_taken[page_zonenum(page)] += nr_pages; - list_move(&page->lru, dst); + move_to = dst; +move: + list_move(&page->lru, move_to); } /* @@ -2190,7 +2124,8 @@ static unsigned long isolate_lru_pages(unsigned long nr_to_scan, } *nr_scanned = total_scan; trace_mm_vmscan_lru_isolate(sc->reclaim_idx, sc->order, nr_to_scan, - total_scan, skipped, nr_taken, mode, lru); + total_scan, skipped, nr_taken, + sc->may_unmap ? 0 : ISOLATE_UNMAPPED, lru); update_lru_sizes(lruvec, lru, nr_zone_taken); return nr_taken; } -- cgit v1.2.3 From 356ea3865687926e5da7579d1f3351d3f0a322a1 Mon Sep 17 00:00:00 2001 From: "andrew.yang" Date: Tue, 22 Mar 2022 14:46:08 -0700 Subject: mm/migrate: fix race between lock page and clear PG_Isolated When memory is tight, system may start to compact memory for large continuous memory demands. If one process tries to lock a memory page that is being locked and isolated for compaction, it may wait a long time or even forever. This is because compaction will perform non-atomic PG_Isolated clear while holding page lock, this may overwrite PG_waiters set by the process that can't obtain the page lock and add itself to the waiting queue to wait for the lock to be unlocked. CPU1 CPU2 lock_page(page); (successful) lock_page(); (failed) __ClearPageIsolated(page); SetPageWaiters(page) (may be overwritten) unlock_page(page); The solution is to not perform non-atomic operation on page flags while holding page lock. Link: https://lkml.kernel.org/r/20220315030515.20263-1-andrew.yang@mediatek.com Signed-off-by: andrew.yang Cc: Matthias Brugger Cc: Matthew Wilcox Cc: "Vlastimil Babka" Cc: David Howells Cc: "William Kucharski" Cc: David Hildenbrand Cc: Yang Shi Cc: Marc Zyngier Cc: Nicholas Tang Cc: Kuan-Ying Lee Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/page-flags.h | 2 +- mm/migrate.c | 12 ++++++------ 2 files changed, 7 insertions(+), 7 deletions(-) (limited to 'include/linux') diff --git a/include/linux/page-flags.h b/include/linux/page-flags.h index 340cb8156568..88fe1d759cdd 100644 --- a/include/linux/page-flags.h +++ b/include/linux/page-flags.h @@ -1000,7 +1000,7 @@ PAGE_TYPE_OPS(Guard, guard) extern bool is_free_buddy_page(struct page *page); -__PAGEFLAG(Isolated, isolated, PF_ANY); +PAGEFLAG(Isolated, isolated, PF_ANY); #ifdef CONFIG_MMU #define __PG_MLOCKED (1UL << PG_mlocked) diff --git a/mm/migrate.c b/mm/migrate.c index 67616ee4aa26..c0d16f050fec 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -107,7 +107,7 @@ int isolate_movable_page(struct page *page, isolate_mode_t mode) /* Driver shouldn't use PG_isolated bit of page->flags */ WARN_ON_ONCE(PageIsolated(page)); - __SetPageIsolated(page); + SetPageIsolated(page); unlock_page(page); return 0; @@ -126,7 +126,7 @@ static void putback_movable_page(struct page *page) mapping = page_mapping(page); mapping->a_ops->putback_page(page); - __ClearPageIsolated(page); + ClearPageIsolated(page); } /* @@ -159,7 +159,7 @@ void putback_movable_pages(struct list_head *l) if (PageMovable(page)) putback_movable_page(page); else - __ClearPageIsolated(page); + ClearPageIsolated(page); unlock_page(page); put_page(page); } else { @@ -883,7 +883,7 @@ static int move_to_new_page(struct page *newpage, struct page *page, VM_BUG_ON_PAGE(!PageIsolated(page), page); if (!PageMovable(page)) { rc = MIGRATEPAGE_SUCCESS; - __ClearPageIsolated(page); + ClearPageIsolated(page); goto out; } @@ -905,7 +905,7 @@ static int move_to_new_page(struct page *newpage, struct page *page, * We clear PG_movable under page_lock so any compactor * cannot try to migrate this page. */ - __ClearPageIsolated(page); + ClearPageIsolated(page); } /* @@ -1091,7 +1091,7 @@ static int unmap_and_move(new_page_t get_new_page, if (unlikely(__PageMovable(page))) { lock_page(page); if (!PageMovable(page)) - __ClearPageIsolated(page); + ClearPageIsolated(page); unlock_page(page); } goto out; -- cgit v1.2.3 From 27d121d0ec6d604d0147c5b579e4181b688a2d64 Mon Sep 17 00:00:00 2001 From: Hari Bathini Date: Tue, 22 Mar 2022 14:46:14 -0700 Subject: mm/cma: provide option to opt out from exposing pages on activation failure Patch series "powerpc/fadump: handle CMA activation failure appropriately", v3. Commit 072355c1cf2d ("mm/cma: expose all pages to the buddy if activation of an area fails") started exposing all pages to buddy allocator on CMA activation failure. But there can be CMA users that want to handle the reserved memory differently on CMA allocation failure. Provide an option to opt out from exposing pages to buddy for such cases. Link: https://lkml.kernel.org/r/20220117075246.36072-1-hbathini@linux.ibm.com Link: https://lkml.kernel.org/r/20220117075246.36072-2-hbathini@linux.ibm.com Signed-off-by: Hari Bathini Reviewed-by: David Hildenbrand Cc: Oscar Salvador Cc: Mike Kravetz Cc: Mahesh Salgaonkar Cc: Sourabh Jain Cc: Michael Ellerman Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/cma.h | 2 ++ mm/cma.c | 11 +++++++++-- mm/cma.h | 1 + 3 files changed, 12 insertions(+), 2 deletions(-) (limited to 'include/linux') diff --git a/include/linux/cma.h b/include/linux/cma.h index b1ba94f1cc9c..90fd742fd1ef 100644 --- a/include/linux/cma.h +++ b/include/linux/cma.h @@ -58,4 +58,6 @@ extern bool cma_pages_valid(struct cma *cma, const struct page *pages, unsigned extern bool cma_release(struct cma *cma, const struct page *pages, unsigned long count); extern int cma_for_each_area(int (*it)(struct cma *cma, void *data), void *data); + +extern void cma_reserve_pages_on_error(struct cma *cma); #endif diff --git a/mm/cma.c b/mm/cma.c index 5a2cd5851658..eaa4b5c920a2 100644 --- a/mm/cma.c +++ b/mm/cma.c @@ -131,8 +131,10 @@ not_in_zone: bitmap_free(cma->bitmap); out_error: /* Expose all pages to the buddy, they are useless for CMA. */ - for (pfn = base_pfn; pfn < base_pfn + cma->count; pfn++) - free_reserved_page(pfn_to_page(pfn)); + if (!cma->reserve_pages_on_error) { + for (pfn = base_pfn; pfn < base_pfn + cma->count; pfn++) + free_reserved_page(pfn_to_page(pfn)); + } totalcma_pages -= cma->count; cma->count = 0; pr_err("CMA area %s could not be activated\n", cma->name); @@ -150,6 +152,11 @@ static int __init cma_init_reserved_areas(void) } core_initcall(cma_init_reserved_areas); +void __init cma_reserve_pages_on_error(struct cma *cma) +{ + cma->reserve_pages_on_error = true; +} + /** * cma_init_reserved_mem() - create custom contiguous area from reserved memory * @base: Base address of the reserved area diff --git a/mm/cma.h b/mm/cma.h index 2c775877eae2..88a0595670b7 100644 --- a/mm/cma.h +++ b/mm/cma.h @@ -30,6 +30,7 @@ struct cma { /* kobject requires dynamic object */ struct cma_kobject *cma_kobj; #endif + bool reserve_pages_on_error; }; extern struct cma cma_areas[MAX_CMA_AREAS]; -- cgit v1.2.3 From e39bb6be9f2b39a6dbaeff484361de76021b175d Mon Sep 17 00:00:00 2001 From: Huang Ying Date: Tue, 22 Mar 2022 14:46:20 -0700 Subject: NUMA Balancing: add page promotion counter Patch series "NUMA balancing: optimize memory placement for memory tiering system", v13 With the advent of various new memory types, some machines will have multiple types of memory, e.g. DRAM and PMEM (persistent memory). The memory subsystem of these machines can be called memory tiering system, because the performance of the different types of memory are different. After commit c221c0b0308f ("device-dax: "Hotplug" persistent memory for use like normal RAM"), the PMEM could be used as the cost-effective volatile memory in separate NUMA nodes. In a typical memory tiering system, there are CPUs, DRAM and PMEM in each physical NUMA node. The CPUs and the DRAM will be put in one logical node, while the PMEM will be put in another (faked) logical node. To optimize the system overall performance, the hot pages should be placed in DRAM node. To do that, we need to identify the hot pages in the PMEM node and migrate them to DRAM node via NUMA migration. In the original NUMA balancing, there are already a set of existing mechanisms to identify the pages recently accessed by the CPUs in a node and migrate the pages to the node. So we can reuse these mechanisms to build the mechanisms to optimize the page placement in the memory tiering system. This is implemented in this patchset. At the other hand, the cold pages should be placed in PMEM node. So, we also need to identify the cold pages in the DRAM node and migrate them to PMEM node. In commit 26aa2d199d6f ("mm/migrate: demote pages during reclaim"), a mechanism to demote the cold DRAM pages to PMEM node under memory pressure is implemented. Based on that, the cold DRAM pages can be demoted to PMEM node proactively to free some memory space on DRAM node to accommodate the promoted hot PMEM pages. This is implemented in this patchset too. We have tested the solution with the pmbench memory accessing benchmark with the 80:20 read/write ratio and the Gauss access address distribution on a 2 socket Intel server with Optane DC Persistent Memory Model. The test results shows that the pmbench score can improve up to 95.9%. This patch (of 3): In a system with multiple memory types, e.g. DRAM and PMEM, the CPU and DRAM in one socket will be put in one NUMA node as before, while the PMEM will be put in another NUMA node as described in the description of the commit c221c0b0308f ("device-dax: "Hotplug" persistent memory for use like normal RAM"). So, the NUMA balancing mechanism will identify all PMEM accesses as remote access and try to promote the PMEM pages to DRAM. To distinguish the number of the inter-type promoted pages from that of the inter-socket migrated pages. A new vmstat count is added. The counter is per-node (count in the target node). So this can be used to identify promotion imbalance among the NUMA nodes. Link: https://lkml.kernel.org/r/20220301085329.3210428-1-ying.huang@intel.com Link: https://lkml.kernel.org/r/20220221084529.1052339-1-ying.huang@intel.com Link: https://lkml.kernel.org/r/20220221084529.1052339-2-ying.huang@intel.com Signed-off-by: "Huang, Ying" Reviewed-by: Yang Shi Tested-by: Baolin Wang Reviewed-by: Baolin Wang Acked-by: Johannes Weiner Reviewed-by: Oscar Salvador Cc: Michal Hocko Cc: Rik van Riel Cc: Mel Gorman Cc: Peter Zijlstra Cc: Dave Hansen Cc: Zi Yan Cc: Wei Xu Cc: Shakeel Butt Cc: zhongjiang-ali Cc: Feng Tang Cc: Randy Dunlap Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/mmzone.h | 3 +++ include/linux/node.h | 5 +++++ mm/migrate.c | 13 ++++++++++--- mm/vmstat.c | 3 +++ 4 files changed, 21 insertions(+), 3 deletions(-) (limited to 'include/linux') diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h index c9e6a50109b9..310b6e7ce58a 100644 --- a/include/linux/mmzone.h +++ b/include/linux/mmzone.h @@ -221,6 +221,9 @@ enum node_stat_item { NR_PAGETABLE, /* used for pagetables */ #ifdef CONFIG_SWAP NR_SWAPCACHE, +#endif +#ifdef CONFIG_NUMA_BALANCING + PGPROMOTE_SUCCESS, /* promote successfully */ #endif NR_VM_NODE_STAT_ITEMS }; diff --git a/include/linux/node.h b/include/linux/node.h index bb21fd631b16..81bbf1c0afd3 100644 --- a/include/linux/node.h +++ b/include/linux/node.h @@ -181,4 +181,9 @@ static inline void register_hugetlbfs_with_node(node_registration_func_t reg, #define to_node(device) container_of(device, struct node, dev) +static inline bool node_is_toptier(int node) +{ + return node_state(node, N_CPU); +} + #endif /* _LINUX_NODE_H_ */ diff --git a/mm/migrate.c b/mm/migrate.c index c0d16f050fec..dc4adf979201 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -2069,6 +2069,7 @@ int migrate_misplaced_page(struct page *page, struct vm_area_struct *vma, pg_data_t *pgdat = NODE_DATA(node); int isolated; int nr_remaining; + unsigned int nr_succeeded; LIST_HEAD(migratepages); new_page_t *new; bool compound; @@ -2107,7 +2108,8 @@ int migrate_misplaced_page(struct page *page, struct vm_area_struct *vma, list_add(&page->lru, &migratepages); nr_remaining = migrate_pages(&migratepages, *new, NULL, node, - MIGRATE_ASYNC, MR_NUMA_MISPLACED, NULL); + MIGRATE_ASYNC, MR_NUMA_MISPLACED, + &nr_succeeded); if (nr_remaining) { if (!list_empty(&migratepages)) { list_del(&page->lru); @@ -2116,8 +2118,13 @@ int migrate_misplaced_page(struct page *page, struct vm_area_struct *vma, putback_lru_page(page); } isolated = 0; - } else - count_vm_numa_events(NUMA_PAGE_MIGRATE, nr_pages); + } + if (nr_succeeded) { + count_vm_numa_events(NUMA_PAGE_MIGRATE, nr_succeeded); + if (!node_is_toptier(page_to_nid(page)) && node_is_toptier(node)) + mod_node_page_state(pgdat, PGPROMOTE_SUCCESS, + nr_succeeded); + } BUG_ON(!list_empty(&migratepages)); return isolated; diff --git a/mm/vmstat.c b/mm/vmstat.c index 4057372745d0..846b670dd346 100644 --- a/mm/vmstat.c +++ b/mm/vmstat.c @@ -1242,6 +1242,9 @@ const char * const vmstat_text[] = { #ifdef CONFIG_SWAP "nr_swapcached", #endif +#ifdef CONFIG_NUMA_BALANCING + "pgpromote_success", +#endif /* enum writeback_stat_item counters */ "nr_dirty_threshold", -- cgit v1.2.3 From c574bbe917036c8968b984c82c7b13194fe5ce98 Mon Sep 17 00:00:00 2001 From: Huang Ying Date: Tue, 22 Mar 2022 14:46:23 -0700 Subject: NUMA balancing: optimize page placement for memory tiering system With the advent of various new memory types, some machines will have multiple types of memory, e.g. DRAM and PMEM (persistent memory). The memory subsystem of these machines can be called memory tiering system, because the performance of the different types of memory are usually different. In such system, because of the memory accessing pattern changing etc, some pages in the slow memory may become hot globally. So in this patch, the NUMA balancing mechanism is enhanced to optimize the page placement among the different memory types according to hot/cold dynamically. In a typical memory tiering system, there are CPUs, fast memory and slow memory in each physical NUMA node. The CPUs and the fast memory will be put in one logical node (called fast memory node), while the slow memory will be put in another (faked) logical node (called slow memory node). That is, the fast memory is regarded as local while the slow memory is regarded as remote. So it's possible for the recently accessed pages in the slow memory node to be promoted to the fast memory node via the existing NUMA balancing mechanism. The original NUMA balancing mechanism will stop to migrate pages if the free memory of the target node becomes below the high watermark. This is a reasonable policy if there's only one memory type. But this makes the original NUMA balancing mechanism almost do not work to optimize page placement among different memory types. Details are as follows. It's the common cases that the working-set size of the workload is larger than the size of the fast memory nodes. Otherwise, it's unnecessary to use the slow memory at all. So, there are almost always no enough free pages in the fast memory nodes, so that the globally hot pages in the slow memory node cannot be promoted to the fast memory node. To solve the issue, we have 2 choices as follows, a. Ignore the free pages watermark checking when promoting hot pages from the slow memory node to the fast memory node. This will create some memory pressure in the fast memory node, thus trigger the memory reclaiming. So that, the cold pages in the fast memory node will be demoted to the slow memory node. b. Define a new watermark called wmark_promo which is higher than wmark_high, and have kswapd reclaiming pages until free pages reach such watermark. The scenario is as follows: when we want to promote hot-pages from a slow memory to a fast memory, but fast memory's free pages would go lower than high watermark with such promotion, we wake up kswapd with wmark_promo watermark in order to demote cold pages and free us up some space. So, next time we want to promote hot-pages we might have a chance of doing so. The choice "a" may create high memory pressure in the fast memory node. If the memory pressure of the workload is high, the memory pressure may become so high that the memory allocation latency of the workload is influenced, e.g. the direct reclaiming may be triggered. The choice "b" works much better at this aspect. If the memory pressure of the workload is high, the hot pages promotion will stop earlier because its allocation watermark is higher than that of the normal memory allocation. So in this patch, choice "b" is implemented. A new zone watermark (WMARK_PROMO) is added. Which is larger than the high watermark and can be controlled via watermark_scale_factor. In addition to the original page placement optimization among sockets, the NUMA balancing mechanism is extended to be used to optimize page placement according to hot/cold among different memory types. So the sysctl user space interface (numa_balancing) is extended in a backward compatible way as follow, so that the users can enable/disable these functionality individually. The sysctl is converted from a Boolean value to a bits field. The definition of the flags is, - 0: NUMA_BALANCING_DISABLED - 1: NUMA_BALANCING_NORMAL - 2: NUMA_BALANCING_MEMORY_TIERING We have tested the patch with the pmbench memory accessing benchmark with the 80:20 read/write ratio and the Gauss access address distribution on a 2 socket Intel server with Optane DC Persistent Memory Model. The test results shows that the pmbench score can improve up to 95.9%. Thanks Andrew Morton to help fix the document format error. Link: https://lkml.kernel.org/r/20220221084529.1052339-3-ying.huang@intel.com Signed-off-by: "Huang, Ying" Tested-by: Baolin Wang Reviewed-by: Baolin Wang Acked-by: Johannes Weiner Reviewed-by: Oscar Salvador Reviewed-by: Yang Shi Cc: Michal Hocko Cc: Rik van Riel Cc: Mel Gorman Cc: Peter Zijlstra Cc: Dave Hansen Cc: Zi Yan Cc: Wei Xu Cc: Shakeel Butt Cc: zhongjiang-ali Cc: Randy Dunlap Cc: Feng Tang Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- Documentation/admin-guide/sysctl/kernel.rst | 29 ++++++++++++++++++++--------- include/linux/mmzone.h | 1 + include/linux/sched/sysctl.h | 10 ++++++++++ kernel/sched/core.c | 21 +++++++++++++++++---- kernel/sysctl.c | 2 +- mm/migrate.c | 16 ++++++++++++++-- mm/page_alloc.c | 3 ++- mm/vmscan.c | 6 +++++- 8 files changed, 70 insertions(+), 18 deletions(-) (limited to 'include/linux') diff --git a/Documentation/admin-guide/sysctl/kernel.rst b/Documentation/admin-guide/sysctl/kernel.rst index d359bcfadd39..fdfd2b684822 100644 --- a/Documentation/admin-guide/sysctl/kernel.rst +++ b/Documentation/admin-guide/sysctl/kernel.rst @@ -595,16 +595,23 @@ Documentation/admin-guide/kernel-parameters.rst). numa_balancing ============== -Enables/disables automatic page fault based NUMA memory -balancing. Memory is moved automatically to nodes -that access it often. +Enables/disables and configures automatic page fault based NUMA memory +balancing. Memory is moved automatically to nodes that access it often. +The value to set can be the result of ORing the following: -Enables/disables automatic NUMA memory balancing. On NUMA machines, there -is a performance penalty if remote memory is accessed by a CPU. When this -feature is enabled the kernel samples what task thread is accessing memory -by periodically unmapping pages and later trapping a page fault. At the -time of the page fault, it is determined if the data being accessed should -be migrated to a local memory node. += ================================= +0 NUMA_BALANCING_DISABLED +1 NUMA_BALANCING_NORMAL +2 NUMA_BALANCING_MEMORY_TIERING += ================================= + +Or NUMA_BALANCING_NORMAL to optimize page placement among different +NUMA nodes to reduce remote accessing. On NUMA machines, there is a +performance penalty if remote memory is accessed by a CPU. When this +feature is enabled the kernel samples what task thread is accessing +memory by periodically unmapping pages and later trapping a page +fault. At the time of the page fault, it is determined if the data +being accessed should be migrated to a local memory node. The unmapping of pages and trapping faults incur additional overhead that ideally is offset by improved memory locality but there is no universal @@ -615,6 +622,10 @@ faults may be controlled by the `numa_balancing_scan_period_min_ms, numa_balancing_scan_delay_ms, numa_balancing_scan_period_max_ms, numa_balancing_scan_size_mb`_, and numa_balancing_settle_count sysctls. +Or NUMA_BALANCING_MEMORY_TIERING to optimize page placement among +different types of memory (represented as different NUMA nodes) to +place the hot pages in the fast memory. This is implemented based on +unmapping and page fault too. numa_balancing_scan_period_min_ms, numa_balancing_scan_delay_ms, numa_balancing_scan_period_max_ms, numa_balancing_scan_size_mb =============================================================================================================================== diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h index 310b6e7ce58a..962b14d403e8 100644 --- a/include/linux/mmzone.h +++ b/include/linux/mmzone.h @@ -353,6 +353,7 @@ enum zone_watermarks { WMARK_MIN, WMARK_LOW, WMARK_HIGH, + WMARK_PROMO, NR_WMARK }; diff --git a/include/linux/sched/sysctl.h b/include/linux/sched/sysctl.h index c19dd5a2c05c..b5eec8854c5a 100644 --- a/include/linux/sched/sysctl.h +++ b/include/linux/sched/sysctl.h @@ -23,6 +23,16 @@ enum sched_tunable_scaling { SCHED_TUNABLESCALING_END, }; +#define NUMA_BALANCING_DISABLED 0x0 +#define NUMA_BALANCING_NORMAL 0x1 +#define NUMA_BALANCING_MEMORY_TIERING 0x2 + +#ifdef CONFIG_NUMA_BALANCING +extern int sysctl_numa_balancing_mode; +#else +#define sysctl_numa_balancing_mode 0 +#endif + /* * control realtime throttling: * diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 9745613d531c..da6a60383645 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -4279,7 +4279,9 @@ DEFINE_STATIC_KEY_FALSE(sched_numa_balancing); #ifdef CONFIG_NUMA_BALANCING -void set_numabalancing_state(bool enabled) +int sysctl_numa_balancing_mode; + +static void __set_numabalancing_state(bool enabled) { if (enabled) static_branch_enable(&sched_numa_balancing); @@ -4287,13 +4289,22 @@ void set_numabalancing_state(bool enabled) static_branch_disable(&sched_numa_balancing); } +void set_numabalancing_state(bool enabled) +{ + if (enabled) + sysctl_numa_balancing_mode = NUMA_BALANCING_NORMAL; + else + sysctl_numa_balancing_mode = NUMA_BALANCING_DISABLED; + __set_numabalancing_state(enabled); +} + #ifdef CONFIG_PROC_SYSCTL int sysctl_numa_balancing(struct ctl_table *table, int write, void *buffer, size_t *lenp, loff_t *ppos) { struct ctl_table t; int err; - int state = static_branch_likely(&sched_numa_balancing); + int state = sysctl_numa_balancing_mode; if (write && !capable(CAP_SYS_ADMIN)) return -EPERM; @@ -4303,8 +4314,10 @@ int sysctl_numa_balancing(struct ctl_table *table, int write, err = proc_dointvec_minmax(&t, write, buffer, lenp, ppos); if (err < 0) return err; - if (write) - set_numabalancing_state(state); + if (write) { + sysctl_numa_balancing_mode = state; + __set_numabalancing_state(state); + } return err; } #endif diff --git a/kernel/sysctl.c b/kernel/sysctl.c index 730ab56d9e92..3395b99d59a4 100644 --- a/kernel/sysctl.c +++ b/kernel/sysctl.c @@ -1696,7 +1696,7 @@ static struct ctl_table kern_table[] = { .mode = 0644, .proc_handler = sysctl_numa_balancing, .extra1 = SYSCTL_ZERO, - .extra2 = SYSCTL_ONE, + .extra2 = SYSCTL_FOUR, }, #endif /* CONFIG_NUMA_BALANCING */ { diff --git a/mm/migrate.c b/mm/migrate.c index dc4adf979201..78b2cf87946d 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -51,6 +51,7 @@ #include #include #include +#include #include @@ -2031,16 +2032,27 @@ static int numamigrate_isolate_page(pg_data_t *pgdat, struct page *page) { int page_lru; int nr_pages = thp_nr_pages(page); + int order = compound_order(page); - VM_BUG_ON_PAGE(compound_order(page) && !PageTransHuge(page), page); + VM_BUG_ON_PAGE(order && !PageTransHuge(page), page); /* Do not migrate THP mapped by multiple processes */ if (PageTransHuge(page) && total_mapcount(page) > 1) return 0; /* Avoid migrating to a node that is nearly full */ - if (!migrate_balanced_pgdat(pgdat, nr_pages)) + if (!migrate_balanced_pgdat(pgdat, nr_pages)) { + int z; + + if (!(sysctl_numa_balancing_mode & NUMA_BALANCING_MEMORY_TIERING)) + return 0; + for (z = pgdat->nr_zones - 1; z >= 0; z--) { + if (populated_zone(pgdat->node_zones + z)) + break; + } + wakeup_kswapd(pgdat->node_zones + z, 0, order, ZONE_MOVABLE); return 0; + } if (isolate_lru_page(page)) return 0; diff --git a/mm/page_alloc.c b/mm/page_alloc.c index a573aa9f5160..8b18a077c409 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -8441,7 +8441,8 @@ static void __setup_per_zone_wmarks(void) zone->watermark_boost = 0; zone->_watermark[WMARK_LOW] = min_wmark_pages(zone) + tmp; - zone->_watermark[WMARK_HIGH] = min_wmark_pages(zone) + tmp * 2; + zone->_watermark[WMARK_HIGH] = low_wmark_pages(zone) + tmp; + zone->_watermark[WMARK_PROMO] = high_wmark_pages(zone) + tmp; spin_unlock_irqrestore(&zone->lock, flags); } diff --git a/mm/vmscan.c b/mm/vmscan.c index f5ec53f19f3b..499fa86e754a 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -56,6 +56,7 @@ #include #include +#include #include "internal.h" @@ -3895,7 +3896,10 @@ static bool pgdat_balanced(pg_data_t *pgdat, int order, int highest_zoneidx) if (!managed_zone(zone)) continue; - mark = high_wmark_pages(zone); + if (sysctl_numa_balancing_mode & NUMA_BALANCING_MEMORY_TIERING) + mark = wmark_pages(zone, WMARK_PROMO); + else + mark = high_wmark_pages(zone); if (zone_watermark_ok_safe(zone, order, mark, highest_zoneidx)) return true; } -- cgit v1.2.3 From 4d45c3aff5ebf80d329eba0f90544d20224f612d Mon Sep 17 00:00:00 2001 From: Yang Yang Date: Tue, 22 Mar 2022 14:46:33 -0700 Subject: mm/vmstat: add event for ksm swapping in copy When faults in from swap what used to be a KSM page and that page had been swapped in before, system has to make a copy, and leaves remerging the pages to a later pass of ksmd. That is not good for performace, we'd better to reduce this kind of copy. There are some ways to reduce it, for example lessen swappiness or madvise(, , MADV_MERGEABLE) range. So add this event to support doing this tuning. Just like this patch: "mm, THP, swap: add THP swapping out fallback counting". Link: https://lkml.kernel.org/r/20220113023839.758845-1-yang.yang29@zte.com.cn Signed-off-by: Yang Yang Reviewed-by: Ran Xiaokai Cc: Hugh Dickins Cc: Yang Shi Cc: Dave Hansen Cc: Saravanan D Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/vm_event_item.h | 3 +++ mm/ksm.c | 3 +++ mm/vmstat.c | 3 +++ 3 files changed, 9 insertions(+) (limited to 'include/linux') diff --git a/include/linux/vm_event_item.h b/include/linux/vm_event_item.h index 7b2363388bfa..16a0a4fd000b 100644 --- a/include/linux/vm_event_item.h +++ b/include/linux/vm_event_item.h @@ -129,6 +129,9 @@ enum vm_event_item { PGPGIN, PGPGOUT, PSWPIN, PSWPOUT, #ifdef CONFIG_SWAP SWAP_RA, SWAP_RA_HIT, +#ifdef CONFIG_KSM + KSM_SWPIN_COPY, +#endif #endif #ifdef CONFIG_X86 DIRECT_MAP_LEVEL2_SPLIT, diff --git a/mm/ksm.c b/mm/ksm.c index c20bd4d9a0d9..4a7f8614e57d 100644 --- a/mm/ksm.c +++ b/mm/ksm.c @@ -2595,6 +2595,9 @@ struct page *ksm_might_need_to_copy(struct page *page, SetPageDirty(new_page); __SetPageUptodate(new_page); __SetPageLocked(new_page); +#ifdef CONFIG_SWAP + count_vm_event(KSM_SWPIN_COPY); +#endif } return new_page; diff --git a/mm/vmstat.c b/mm/vmstat.c index 846b670dd346..d5cc8d739fac 100644 --- a/mm/vmstat.c +++ b/mm/vmstat.c @@ -1388,6 +1388,9 @@ const char * const vmstat_text[] = { #ifdef CONFIG_SWAP "swap_ra", "swap_ra_hit", +#ifdef CONFIG_KSM + "ksm_swpin_copy", +#endif #endif #ifdef CONFIG_X86 "direct_map_level2_splits", -- cgit v1.2.3 From e930d999715073a70d306fb59a394ea8b84d0b45 Mon Sep 17 00:00:00 2001 From: Michal Hocko Date: Tue, 22 Mar 2022 14:46:51 -0700 Subject: mm, memory_hotplug: make arch_alloc_nodedata independent on CONFIG_MEMORY_HOTPLUG Patch series "mm, memory_hotplug: handle unitialized numa node gracefully". The core of the fix is patch 2 which also links existing bug reports. The high level goal is to have all possible numa nodes have their pgdat allocated and initialized so for_each_possible_node(nid) NODE_DATA(nid) will never return garbage. This has proven to be problem in several places when an offline numa node is used for an allocation just to realize that node_data and therefore allocation fallback zonelists are not initialized and such an allocation request blows up. There were attempts to address that by checking node_online in several places including the page allocator. This patchset approaches the problem from a different perspective and instead of special casing, which just adds a runtime overhead, it allocates pglist_data for each possible node. This can add some memory overhead for platforms with high number of possible nodes if they do not contain any memory. This should be a rather rare configuration though. How to test this? David has provided and excellent howto: http://lkml.kernel.org/r/6e5ebc19-890c-b6dd-1924-9f25c441010d@redhat.com Patches 1 and 3-6 are mostly cleanups. The patchset has been reviewed by Rafael (thanks!) and the core fix tested by Rafael and Alexey (thanks to both). David has tested as per instructions above and hasn't found any fallouts in the memory hotplug scenarios. This patch (of 6): This is a preparatory patch and it doesn't introduce any functional change. It merely pulls out arch_alloc_nodedata (and co) outside of CONFIG_MEMORY_HOTPLUG because the following patch will need to call this from the generic MM code. Link: https://lkml.kernel.org/r/20220127085305.20890-1-mhocko@kernel.org Link: https://lkml.kernel.org/r/20220127085305.20890-2-mhocko@kernel.org Signed-off-by: Michal Hocko Acked-by: Rafael Aquini Acked-by: David Hildenbrand Acked-by: Mike Rapoport Reviewed-by: Oscar Salvador Reviewed-by: Wei Yang Cc: Alexey Makhalov Cc: Christoph Lameter Cc: Dennis Zhou Cc: Eric Dumazet Cc: Nico Pache Cc: Tejun Heo Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/ia64/mm/discontig.c | 2 - include/linux/memory_hotplug.h | 119 ++++++++++++++++++++--------------------- 2 files changed, 59 insertions(+), 62 deletions(-) (limited to 'include/linux') diff --git a/arch/ia64/mm/discontig.c b/arch/ia64/mm/discontig.c index 791d4176e4a6..8dc8a554f774 100644 --- a/arch/ia64/mm/discontig.c +++ b/arch/ia64/mm/discontig.c @@ -608,7 +608,6 @@ void __init paging_init(void) zero_page_memmap_ptr = virt_to_page(ia64_imva(empty_zero_page)); } -#ifdef CONFIG_MEMORY_HOTPLUG pg_data_t *arch_alloc_nodedata(int nid) { unsigned long size = compute_pernodesize(nid); @@ -626,7 +625,6 @@ void arch_refresh_nodedata(int update_node, pg_data_t *update_pgdat) pgdat_list[update_node] = update_pgdat; scatter_node_data(); } -#endif #ifdef CONFIG_SPARSEMEM_VMEMMAP int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node, diff --git a/include/linux/memory_hotplug.h b/include/linux/memory_hotplug.h index be48e003a518..4355983b364d 100644 --- a/include/linux/memory_hotplug.h +++ b/include/linux/memory_hotplug.h @@ -16,6 +16,65 @@ struct memory_group; struct resource; struct vmem_altmap; +#ifdef CONFIG_HAVE_ARCH_NODEDATA_EXTENSION +/* + * For supporting node-hotadd, we have to allocate a new pgdat. + * + * If an arch has generic style NODE_DATA(), + * node_data[nid] = kzalloc() works well. But it depends on the architecture. + * + * In general, generic_alloc_nodedata() is used. + * Now, arch_free_nodedata() is just defined for error path of node_hot_add. + * + */ +extern pg_data_t *arch_alloc_nodedata(int nid); +extern void arch_free_nodedata(pg_data_t *pgdat); +extern void arch_refresh_nodedata(int nid, pg_data_t *pgdat); + +#else /* CONFIG_HAVE_ARCH_NODEDATA_EXTENSION */ + +#define arch_alloc_nodedata(nid) generic_alloc_nodedata(nid) +#define arch_free_nodedata(pgdat) generic_free_nodedata(pgdat) + +#ifdef CONFIG_NUMA +/* + * XXX: node aware allocation can't work well to get new node's memory at this time. + * Because, pgdat for the new node is not allocated/initialized yet itself. + * To use new node's memory, more consideration will be necessary. + */ +#define generic_alloc_nodedata(nid) \ +({ \ + kzalloc(sizeof(pg_data_t), GFP_KERNEL); \ +}) +/* + * This definition is just for error path in node hotadd. + * For node hotremove, we have to replace this. + */ +#define generic_free_nodedata(pgdat) kfree(pgdat) + +extern pg_data_t *node_data[]; +static inline void arch_refresh_nodedata(int nid, pg_data_t *pgdat) +{ + node_data[nid] = pgdat; +} + +#else /* !CONFIG_NUMA */ + +/* never called */ +static inline pg_data_t *generic_alloc_nodedata(int nid) +{ + BUG(); + return NULL; +} +static inline void generic_free_nodedata(pg_data_t *pgdat) +{ +} +static inline void arch_refresh_nodedata(int nid, pg_data_t *pgdat) +{ +} +#endif /* CONFIG_NUMA */ +#endif /* CONFIG_HAVE_ARCH_NODEDATA_EXTENSION */ + #ifdef CONFIG_MEMORY_HOTPLUG struct page *pfn_to_online_page(unsigned long pfn); @@ -154,66 +213,6 @@ int add_pages(int nid, unsigned long start_pfn, unsigned long nr_pages, struct mhp_params *params); #endif /* ARCH_HAS_ADD_PAGES */ -#ifdef CONFIG_HAVE_ARCH_NODEDATA_EXTENSION -/* - * For supporting node-hotadd, we have to allocate a new pgdat. - * - * If an arch has generic style NODE_DATA(), - * node_data[nid] = kzalloc() works well. But it depends on the architecture. - * - * In general, generic_alloc_nodedata() is used. - * Now, arch_free_nodedata() is just defined for error path of node_hot_add. - * - */ -extern pg_data_t *arch_alloc_nodedata(int nid); -extern void arch_free_nodedata(pg_data_t *pgdat); -extern void arch_refresh_nodedata(int nid, pg_data_t *pgdat); - -#else /* CONFIG_HAVE_ARCH_NODEDATA_EXTENSION */ - -#define arch_alloc_nodedata(nid) generic_alloc_nodedata(nid) -#define arch_free_nodedata(pgdat) generic_free_nodedata(pgdat) - -#ifdef CONFIG_NUMA -/* - * If ARCH_HAS_NODEDATA_EXTENSION=n, this func is used to allocate pgdat. - * XXX: kmalloc_node() can't work well to get new node's memory at this time. - * Because, pgdat for the new node is not allocated/initialized yet itself. - * To use new node's memory, more consideration will be necessary. - */ -#define generic_alloc_nodedata(nid) \ -({ \ - kzalloc(sizeof(pg_data_t), GFP_KERNEL); \ -}) -/* - * This definition is just for error path in node hotadd. - * For node hotremove, we have to replace this. - */ -#define generic_free_nodedata(pgdat) kfree(pgdat) - -extern pg_data_t *node_data[]; -static inline void arch_refresh_nodedata(int nid, pg_data_t *pgdat) -{ - node_data[nid] = pgdat; -} - -#else /* !CONFIG_NUMA */ - -/* never called */ -static inline pg_data_t *generic_alloc_nodedata(int nid) -{ - BUG(); - return NULL; -} -static inline void generic_free_nodedata(pg_data_t *pgdat) -{ -} -static inline void arch_refresh_nodedata(int nid, pg_data_t *pgdat) -{ -} -#endif /* CONFIG_NUMA */ -#endif /* CONFIG_HAVE_ARCH_NODEDATA_EXTENSION */ - void get_online_mems(void); void put_online_mems(void); -- cgit v1.2.3 From 09f49dca570a917a8c6bccd7e8c61f5141534e3a Mon Sep 17 00:00:00 2001 From: Michal Hocko Date: Tue, 22 Mar 2022 14:46:54 -0700 Subject: mm: handle uninitialized numa nodes gracefully We have had several reports [1][2][3] that page allocator blows up when an allocation from a possible node is requested. The underlying reason is that NODE_DATA for the specific node is not allocated. NUMA specific initialization is arch specific and it can vary a lot. E.g. x86 tries to initialize all nodes that have some cpu affinity (see init_cpu_to_node) but this can be insufficient because the node might be cpuless for example. One way to address this problem would be to check for !node_online nodes when trying to get a zonelist and silently fall back to another node. That is unfortunately adding a branch into allocator hot path and it doesn't handle any other potential NODE_DATA users. This patch takes a different approach (following a lead of [3]) and it pre allocates pgdat for all possible nodes in an arch indipendent code - free_area_init. All uninitialized nodes are treated as memoryless nodes. node_state of the node is not changed because that would lead to other side effects - e.g. sysfs representation of such a node and from past discussions [4] it is known that some tools might have problems digesting that. Newly allocated pgdat only gets a minimal initialization and the rest of the work is expected to be done by the memory hotplug - hotadd_new_pgdat (renamed to hotadd_init_pgdat). generic_alloc_nodedata is changed to use the memblock allocator because neither page nor slab allocators are available at the stage when all pgdats are allocated. Hotplug doesn't allocate pgdat anymore so we can use the early boot allocator. The only arch specific implementation is ia64 and that is changed to use the early allocator as well. [1] http://lkml.kernel.org/r/20211101201312.11589-1-amakhalov@vmware.com [2] http://lkml.kernel.org/r/20211207224013.880775-1-npache@redhat.com [3] http://lkml.kernel.org/r/20190114082416.30939-1-mhocko@kernel.org [4] http://lkml.kernel.org/r/20200428093836.27190-1-srikar@linux.vnet.ibm.com [akpm@linux-foundation.org: replace comment, per Mike] Link: https://lkml.kernel.org/r/Yfe7RBeLCijnWBON@dhcp22.suse.cz Reported-by: Alexey Makhalov Tested-by: Alexey Makhalov Reported-by: Nico Pache Acked-by: Rafael Aquini Tested-by: Rafael Aquini Acked-by: David Hildenbrand Reviewed-by: Oscar Salvador Acked-by: Mike Rapoport Signed-off-by: Michal Hocko Cc: Christoph Lameter Cc: Dennis Zhou Cc: Eric Dumazet Cc: Tejun Heo Cc: Wei Yang Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/ia64/mm/discontig.c | 4 ++-- include/linux/memory_hotplug.h | 2 +- mm/internal.h | 2 ++ mm/memory_hotplug.c | 21 +++++++++------------ mm/page_alloc.c | 40 ++++++++++++++++++++++++++++++++++++---- 5 files changed, 50 insertions(+), 19 deletions(-) (limited to 'include/linux') diff --git a/arch/ia64/mm/discontig.c b/arch/ia64/mm/discontig.c index 8dc8a554f774..dd0cf4834eaa 100644 --- a/arch/ia64/mm/discontig.c +++ b/arch/ia64/mm/discontig.c @@ -608,11 +608,11 @@ void __init paging_init(void) zero_page_memmap_ptr = virt_to_page(ia64_imva(empty_zero_page)); } -pg_data_t *arch_alloc_nodedata(int nid) +pg_data_t * __init arch_alloc_nodedata(int nid) { unsigned long size = compute_pernodesize(nid); - return kzalloc(size, GFP_KERNEL); + return memblock_alloc(size, SMP_CACHE_BYTES); } void arch_free_nodedata(pg_data_t *pgdat) diff --git a/include/linux/memory_hotplug.h b/include/linux/memory_hotplug.h index 4355983b364d..cdd66bfdf855 100644 --- a/include/linux/memory_hotplug.h +++ b/include/linux/memory_hotplug.h @@ -44,7 +44,7 @@ extern void arch_refresh_nodedata(int nid, pg_data_t *pgdat); */ #define generic_alloc_nodedata(nid) \ ({ \ - kzalloc(sizeof(pg_data_t), GFP_KERNEL); \ + memblock_alloc(sizeof(*pgdat), SMP_CACHE_BYTES); \ }) /* * This definition is just for error path in node hotadd. diff --git a/mm/internal.h b/mm/internal.h index 9c298afb9688..f1554a4e249e 100644 --- a/mm/internal.h +++ b/mm/internal.h @@ -707,4 +707,6 @@ void vunmap_range_noflush(unsigned long start, unsigned long end); int numa_migrate_prep(struct page *page, struct vm_area_struct *vma, unsigned long addr, int page_nid, int *flags); +DECLARE_PER_CPU(struct per_cpu_nodestat, boot_nodestats); + #endif /* __MM_INTERNAL_H */ diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index 0139b77c51d5..11f39d0e76ec 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -1162,19 +1162,21 @@ static void reset_node_present_pages(pg_data_t *pgdat) } /* we are OK calling __meminit stuff here - we have CONFIG_MEMORY_HOTPLUG */ -static pg_data_t __ref *hotadd_new_pgdat(int nid) +static pg_data_t __ref *hotadd_init_pgdat(int nid) { struct pglist_data *pgdat; pgdat = NODE_DATA(nid); - if (!pgdat) { - pgdat = arch_alloc_nodedata(nid); - if (!pgdat) - return NULL; + /* + * NODE_DATA is preallocated (free_area_init) but its internal + * state is not allocated completely. Add missing pieces. + * Completely offline nodes stay around and they just need + * reintialization. + */ + if (pgdat->per_cpu_nodestats == &boot_nodestats) { pgdat->per_cpu_nodestats = alloc_percpu(struct per_cpu_nodestat); - arch_refresh_nodedata(nid, pgdat); } else { int cpu; /* @@ -1193,8 +1195,6 @@ static pg_data_t __ref *hotadd_new_pgdat(int nid) } } - /* we can use NODE_DATA(nid) from here */ - pgdat->node_id = nid; pgdat->node_start_pfn = 0; /* init node's zones as empty zones, we don't have any present pages.*/ @@ -1246,7 +1246,7 @@ static int __try_online_node(int nid, bool set_node_online) if (node_online(nid)) return 0; - pgdat = hotadd_new_pgdat(nid); + pgdat = hotadd_init_pgdat(nid); if (!pgdat) { pr_err("Cannot online node %d due to NULL pgdat\n", nid); ret = -ENOMEM; @@ -1445,9 +1445,6 @@ int __ref add_memory_resource(int nid, struct resource *res, mhp_t mhp_flags) return ret; error: - /* rollback pgdat allocation and others */ - if (new_node) - rollback_node_hotadd(nid); if (IS_ENABLED(CONFIG_ARCH_KEEP_MEMBLOCK)) memblock_remove(start, size); error_mem_hotplug_end: diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 8b18a077c409..4f141a4e5b64 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -6341,7 +6341,7 @@ static void per_cpu_pages_init(struct per_cpu_pages *pcp, struct per_cpu_zonesta #define BOOT_PAGESET_BATCH 1 static DEFINE_PER_CPU(struct per_cpu_pages, boot_pageset); static DEFINE_PER_CPU(struct per_cpu_zonestat, boot_zonestats); -static DEFINE_PER_CPU(struct per_cpu_nodestat, boot_nodestats); +DEFINE_PER_CPU(struct per_cpu_nodestat, boot_nodestats); static void __build_all_zonelists(void *data) { @@ -6363,7 +6363,11 @@ static void __build_all_zonelists(void *data) if (self && !node_online(self->node_id)) { build_zonelists(self); } else { - for_each_online_node(nid) { + /* + * All possible nodes have pgdat preallocated + * in free_area_init + */ + for_each_node(nid) { pg_data_t *pgdat = NODE_DATA(nid); build_zonelists(pgdat); @@ -8063,8 +8067,36 @@ void __init free_area_init(unsigned long *max_zone_pfn) /* Initialise every node */ mminit_verify_pageflags_layout(); setup_nr_node_ids(); - for_each_online_node(nid) { - pg_data_t *pgdat = NODE_DATA(nid); + for_each_node(nid) { + pg_data_t *pgdat; + + if (!node_online(nid)) { + pr_info("Initializing node %d as memoryless\n", nid); + + /* Allocator not initialized yet */ + pgdat = arch_alloc_nodedata(nid); + if (!pgdat) { + pr_err("Cannot allocate %zuB for node %d.\n", + sizeof(*pgdat), nid); + continue; + } + arch_refresh_nodedata(nid, pgdat); + free_area_init_memoryless_node(nid); + + /* + * We do not want to confuse userspace by sysfs + * files/directories for node without any memory + * attached to it, so this node is not marked as + * N_MEMORY and not marked online so that no sysfs + * hierarchy will be created via register_one_node for + * it. The pgdat will get fully initialized by + * hotadd_init_pgdat() when memory is hotplugged into + * this node. + */ + continue; + } + + pgdat = NODE_DATA(nid); free_area_init_node(nid); /* Any memory on that node */ -- cgit v1.2.3 From 390511e1476eb1cc41d420a7661b33f4d8584c3f Mon Sep 17 00:00:00 2001 From: Michal Hocko Date: Tue, 22 Mar 2022 14:46:57 -0700 Subject: mm, memory_hotplug: drop arch_free_nodedata Prior to "mm: handle uninitialized numa nodes gracefully" memory hotplug used to allocate pgdat when memory has been added to a node (hotadd_init_pgdat) arch_free_nodedata has been only used in the failure path because once the pgdat is exported (to be visible by NODA_DATA(nid)) it cannot really be freed because there is no synchronization available for that. pgdat is allocated for each possible nodes now so the memory hotplug doesn't need to do the ever use arch_free_nodedata so drop it. This patch doesn't introduce any functional change. Link: https://lkml.kernel.org/r/20220127085305.20890-4-mhocko@kernel.org Signed-off-by: Michal Hocko Acked-by: Rafael Aquini Acked-by: David Hildenbrand Acked-by: Mike Rapoport Reviewed-by: Oscar Salvador Cc: Alexey Makhalov Cc: Christoph Lameter Cc: Dennis Zhou Cc: Eric Dumazet Cc: Nico Pache Cc: Tejun Heo Cc: Wei Yang Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/ia64/mm/discontig.c | 5 ----- include/linux/memory_hotplug.h | 3 --- mm/memory_hotplug.c | 10 ---------- 3 files changed, 18 deletions(-) (limited to 'include/linux') diff --git a/arch/ia64/mm/discontig.c b/arch/ia64/mm/discontig.c index dd0cf4834eaa..73d0db36edb6 100644 --- a/arch/ia64/mm/discontig.c +++ b/arch/ia64/mm/discontig.c @@ -615,11 +615,6 @@ pg_data_t * __init arch_alloc_nodedata(int nid) return memblock_alloc(size, SMP_CACHE_BYTES); } -void arch_free_nodedata(pg_data_t *pgdat) -{ - kfree(pgdat); -} - void arch_refresh_nodedata(int update_node, pg_data_t *update_pgdat) { pgdat_list[update_node] = update_pgdat; diff --git a/include/linux/memory_hotplug.h b/include/linux/memory_hotplug.h index cdd66bfdf855..60f09d3ebb3d 100644 --- a/include/linux/memory_hotplug.h +++ b/include/linux/memory_hotplug.h @@ -24,17 +24,14 @@ struct vmem_altmap; * node_data[nid] = kzalloc() works well. But it depends on the architecture. * * In general, generic_alloc_nodedata() is used. - * Now, arch_free_nodedata() is just defined for error path of node_hot_add. * */ extern pg_data_t *arch_alloc_nodedata(int nid); -extern void arch_free_nodedata(pg_data_t *pgdat); extern void arch_refresh_nodedata(int nid, pg_data_t *pgdat); #else /* CONFIG_HAVE_ARCH_NODEDATA_EXTENSION */ #define arch_alloc_nodedata(nid) generic_alloc_nodedata(nid) -#define arch_free_nodedata(pgdat) generic_free_nodedata(pgdat) #ifdef CONFIG_NUMA /* diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index 11f39d0e76ec..55c3e5309088 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -1217,16 +1217,6 @@ static pg_data_t __ref *hotadd_init_pgdat(int nid) return pgdat; } -static void rollback_node_hotadd(int nid) -{ - pg_data_t *pgdat = NODE_DATA(nid); - - arch_refresh_nodedata(nid, NULL); - free_percpu(pgdat->per_cpu_nodestats); - arch_free_nodedata(pgdat); -} - - /* * __try_online_node - online a node if offlined * @nid: the node ID -- cgit v1.2.3 From 70b5b46a754245d383811b4d2f2c76c34bb7e145 Mon Sep 17 00:00:00 2001 From: Michal Hocko Date: Tue, 22 Mar 2022 14:47:00 -0700 Subject: mm, memory_hotplug: reorganize new pgdat initialization When a !node_online node is brought up it needs a hotplug specific initialization because the node could be either uninitialized yet or it could have been recycled after previous hotremove. hotadd_init_pgdat is responsible for that. Internal pgdat state is initialized at two places currently - hotadd_init_pgdat - free_area_init_core_hotplug There is no real clear cut what should go where but this patch's chosen to move the whole internal state initialization into free_area_init_core_hotplug. hotadd_init_pgdat is still responsible to pull all the parts together - most notably to initialize zonelists because those depend on the overall topology. This patch doesn't introduce any functional change. Link: https://lkml.kernel.org/r/20220127085305.20890-5-mhocko@kernel.org Signed-off-by: Michal Hocko Acked-by: Rafael Aquini Acked-by: David Hildenbrand Reviewed-by: Oscar Salvador Cc: Alexey Makhalov Cc: Christoph Lameter Cc: Dennis Zhou Cc: Eric Dumazet Cc: Mike Rapoport Cc: Nico Pache Cc: Tejun Heo Cc: Wei Yang Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/memory_hotplug.h | 2 +- mm/memory_hotplug.c | 28 +++------------------------- mm/page_alloc.c | 25 +++++++++++++++++++++++-- 3 files changed, 27 insertions(+), 28 deletions(-) (limited to 'include/linux') diff --git a/include/linux/memory_hotplug.h b/include/linux/memory_hotplug.h index 60f09d3ebb3d..76bf2de86def 100644 --- a/include/linux/memory_hotplug.h +++ b/include/linux/memory_hotplug.h @@ -319,7 +319,7 @@ extern void set_zone_contiguous(struct zone *zone); extern void clear_zone_contiguous(struct zone *zone); #ifdef CONFIG_MEMORY_HOTPLUG -extern void __ref free_area_init_core_hotplug(int nid); +extern void __ref free_area_init_core_hotplug(struct pglist_data *pgdat); extern int __add_memory(int nid, u64 start, u64 size, mhp_t mhp_flags); extern int add_memory(int nid, u64 start, u64 size, mhp_t mhp_flags); extern int add_memory_resource(int nid, struct resource *resource, diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index 55c3e5309088..a4f69d399929 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -1166,39 +1166,16 @@ static pg_data_t __ref *hotadd_init_pgdat(int nid) { struct pglist_data *pgdat; - pgdat = NODE_DATA(nid); - /* * NODE_DATA is preallocated (free_area_init) but its internal * state is not allocated completely. Add missing pieces. * Completely offline nodes stay around and they just need * reintialization. */ - if (pgdat->per_cpu_nodestats == &boot_nodestats) { - pgdat->per_cpu_nodestats = - alloc_percpu(struct per_cpu_nodestat); - } else { - int cpu; - /* - * Reset the nr_zones, order and highest_zoneidx before reuse. - * Note that kswapd will init kswapd_highest_zoneidx properly - * when it starts in the near future. - */ - pgdat->nr_zones = 0; - pgdat->kswapd_order = 0; - pgdat->kswapd_highest_zoneidx = 0; - for_each_online_cpu(cpu) { - struct per_cpu_nodestat *p; - - p = per_cpu_ptr(pgdat->per_cpu_nodestats, cpu); - memset(p, 0, sizeof(*p)); - } - } - - pgdat->node_start_pfn = 0; + pgdat = NODE_DATA(nid); /* init node's zones as empty zones, we don't have any present pages.*/ - free_area_init_core_hotplug(nid); + free_area_init_core_hotplug(pgdat); /* * The node we allocated has no zone fallback lists. For avoiding @@ -1210,6 +1187,7 @@ static pg_data_t __ref *hotadd_init_pgdat(int nid) * When memory is hot-added, all the memory is in offline state. So * clear all zones' present_pages because they will be updated in * online_pages() and offline_pages(). + * TODO: should be in free_area_init_core_hotplug? */ reset_node_managed_pages(pgdat); reset_node_present_pages(pgdat); diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 4f141a4e5b64..d32a635f2c72 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -7466,12 +7466,33 @@ static void __meminit zone_init_internals(struct zone *zone, enum zone_type idx, * NOTE: this function is only called during memory hotplug */ #ifdef CONFIG_MEMORY_HOTPLUG -void __ref free_area_init_core_hotplug(int nid) +void __ref free_area_init_core_hotplug(struct pglist_data *pgdat) { + int nid = pgdat->node_id; enum zone_type z; - pg_data_t *pgdat = NODE_DATA(nid); + int cpu; pgdat_init_internals(pgdat); + + if (pgdat->per_cpu_nodestats == &boot_nodestats) + pgdat->per_cpu_nodestats = alloc_percpu(struct per_cpu_nodestat); + + /* + * Reset the nr_zones, order and highest_zoneidx before reuse. + * Note that kswapd will init kswapd_highest_zoneidx properly + * when it starts in the near future. + */ + pgdat->nr_zones = 0; + pgdat->kswapd_order = 0; + pgdat->kswapd_highest_zoneidx = 0; + pgdat->node_start_pfn = 0; + for_each_online_cpu(cpu) { + struct per_cpu_nodestat *p; + + p = per_cpu_ptr(pgdat->per_cpu_nodestats, cpu); + memset(p, 0, sizeof(*p)); + } + for (z = 0; z < MAX_NR_ZONES; z++) zone_init_internals(&pgdat->node_zones[z], z, nid, 0); } -- cgit v1.2.3 From 2848a28b0a6052a4c8450397d2647d7d8e3f6f06 Mon Sep 17 00:00:00 2001 From: David Hildenbrand Date: Tue, 22 Mar 2022 14:47:13 -0700 Subject: drivers/base/node: consolidate node device subsystem initialization in node_dev_init() ... and call node_dev_init() after memory_dev_init() from driver_init(), so before any of the existing arch/subsys calls. All online nodes should be known at that point: early during boot, arch code determines node and zone ranges and sets the relevant nodes online; usually this happens in setup_arch(). This is in line with memory_dev_init(), which initializes the memory device subsystem and creates all memory block devices. Similar to memory_dev_init(), panic() if anything goes wrong, we don't want to continue with such basic initialization errors. The important part is that node_dev_init() gets called after memory_dev_init() and after cpu_dev_init(), but before any of the relevant archs call register_cpu() to register the new cpu device under the node device. The latter should be the case for the current users of topology_init(). Link: https://lkml.kernel.org/r/20220203105212.30385-1-david@redhat.com Signed-off-by: David Hildenbrand Reviewed-by: Oscar Salvador Tested-by: Anatoly Pugachev (sparc64) Cc: Greg Kroah-Hartman Cc: Michal Hocko Cc: Oscar Salvador Cc: Mike Rapoport Cc: Catalin Marinas Cc: Will Deacon Cc: Thomas Bogendoerfer Cc: Michael Ellerman Cc: Benjamin Herrenschmidt Cc: Paul Mackerras Cc: Paul Walmsley Cc: Palmer Dabbelt Cc: Albert Ou Cc: Heiko Carstens Cc: Vasily Gorbik Cc: Yoshinori Sato Cc: Rich Felker Cc: "David S. Miller" Cc: Thomas Gleixner Cc: Ingo Molnar Cc: Borislav Petkov Cc: Dave Hansen Cc: "Rafael J. Wysocki" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/arm64/kernel/setup.c | 3 --- arch/ia64/kernel/topology.c | 10 ---------- arch/mips/kernel/topology.c | 5 ----- arch/powerpc/kernel/sysfs.c | 17 ----------------- arch/riscv/kernel/setup.c | 3 --- arch/s390/kernel/numa.c | 7 ------- arch/sh/kernel/topology.c | 5 ----- arch/sparc/kernel/sysfs.c | 12 ------------ arch/x86/kernel/topology.c | 5 ----- drivers/base/init.c | 1 + drivers/base/node.c | 30 +++++++++++++++++------------- include/linux/node.h | 4 ++++ 12 files changed, 22 insertions(+), 80 deletions(-) (limited to 'include/linux') diff --git a/arch/arm64/kernel/setup.c b/arch/arm64/kernel/setup.c index f70573928f1b..3505789cf4bd 100644 --- a/arch/arm64/kernel/setup.c +++ b/arch/arm64/kernel/setup.c @@ -406,9 +406,6 @@ static int __init topology_init(void) { int i; - for_each_online_node(i) - register_one_node(i); - for_each_possible_cpu(i) { struct cpu *cpu = &per_cpu(cpu_data.cpu, i); cpu->hotpluggable = cpu_can_disable(i); diff --git a/arch/ia64/kernel/topology.c b/arch/ia64/kernel/topology.c index e4992917a24b..94a848b06f15 100644 --- a/arch/ia64/kernel/topology.c +++ b/arch/ia64/kernel/topology.c @@ -70,16 +70,6 @@ static int __init topology_init(void) { int i, err = 0; -#ifdef CONFIG_NUMA - /* - * MCD - Do we want to register all ONLINE nodes, or all POSSIBLE nodes? - */ - for_each_online_node(i) { - if ((err = register_one_node(i))) - goto out; - } -#endif - sysfs_cpus = kcalloc(NR_CPUS, sizeof(struct ia64_cpu), GFP_KERNEL); if (!sysfs_cpus) panic("kzalloc in topology_init failed - NR_CPUS too big?"); diff --git a/arch/mips/kernel/topology.c b/arch/mips/kernel/topology.c index 08ad6371fbe0..9429d85a4703 100644 --- a/arch/mips/kernel/topology.c +++ b/arch/mips/kernel/topology.c @@ -12,11 +12,6 @@ static int __init topology_init(void) { int i, ret; -#ifdef CONFIG_NUMA - for_each_online_node(i) - register_one_node(i); -#endif /* CONFIG_NUMA */ - for_each_present_cpu(i) { struct cpu *c = &per_cpu(cpu_devices, i); diff --git a/arch/powerpc/kernel/sysfs.c b/arch/powerpc/kernel/sysfs.c index d45a415d5374..2069bbb90a9a 100644 --- a/arch/powerpc/kernel/sysfs.c +++ b/arch/powerpc/kernel/sysfs.c @@ -1110,14 +1110,6 @@ EXPORT_SYMBOL_GPL(cpu_remove_dev_attr_group); /* NUMA stuff */ #ifdef CONFIG_NUMA -static void __init register_nodes(void) -{ - int i; - - for (i = 0; i < MAX_NUMNODES; i++) - register_one_node(i); -} - int sysfs_add_device_to_node(struct device *dev, int nid) { struct node *node = node_devices[nid]; @@ -1132,13 +1124,6 @@ void sysfs_remove_device_from_node(struct device *dev, int nid) sysfs_remove_link(&node->dev.kobj, kobject_name(&dev->kobj)); } EXPORT_SYMBOL_GPL(sysfs_remove_device_from_node); - -#else -static void __init register_nodes(void) -{ - return; -} - #endif /* Only valid if CPU is present. */ @@ -1155,8 +1140,6 @@ static int __init topology_init(void) { int cpu, r; - register_nodes(); - for_each_possible_cpu(cpu) { struct cpu *c = &per_cpu(cpu_devices, cpu); diff --git a/arch/riscv/kernel/setup.c b/arch/riscv/kernel/setup.c index b42bfdc67482..834eb652a7b9 100644 --- a/arch/riscv/kernel/setup.c +++ b/arch/riscv/kernel/setup.c @@ -301,9 +301,6 @@ static int __init topology_init(void) { int i, ret; - for_each_online_node(i) - register_one_node(i); - for_each_possible_cpu(i) { struct cpu *cpu = &per_cpu(cpu_devices, i); diff --git a/arch/s390/kernel/numa.c b/arch/s390/kernel/numa.c index 51c5a9f6e525..23ab9f02f278 100644 --- a/arch/s390/kernel/numa.c +++ b/arch/s390/kernel/numa.c @@ -33,10 +33,3 @@ void __init numa_setup(void) NODE_DATA(0)->node_spanned_pages = memblock_end_of_DRAM() >> PAGE_SHIFT; NODE_DATA(0)->node_id = 0; } - -static int __init numa_init_late(void) -{ - register_one_node(0); - return 0; -} -arch_initcall(numa_init_late); diff --git a/arch/sh/kernel/topology.c b/arch/sh/kernel/topology.c index 76af6db9daa2..2d2a7509b565 100644 --- a/arch/sh/kernel/topology.c +++ b/arch/sh/kernel/topology.c @@ -46,11 +46,6 @@ static int __init topology_init(void) { int i, ret; -#ifdef CONFIG_NUMA - for_each_online_node(i) - register_one_node(i); -#endif - for_each_present_cpu(i) { struct cpu *c = &per_cpu(cpu_devices, i); diff --git a/arch/sparc/kernel/sysfs.c b/arch/sparc/kernel/sysfs.c index 6d60d416f0dd..f19487e4cc71 100644 --- a/arch/sparc/kernel/sysfs.c +++ b/arch/sparc/kernel/sysfs.c @@ -244,22 +244,10 @@ static void __init check_mmu_stats(void) mmu_stats_supported = 1; } -static void register_nodes(void) -{ -#ifdef CONFIG_NUMA - int i; - - for (i = 0; i < MAX_NUMNODES; i++) - register_one_node(i); -#endif -} - static int __init topology_init(void) { int cpu, ret; - register_nodes(); - check_mmu_stats(); for_each_possible_cpu(cpu) { diff --git a/arch/x86/kernel/topology.c b/arch/x86/kernel/topology.c index bd83748e2bde..8617d1ed9d31 100644 --- a/arch/x86/kernel/topology.c +++ b/arch/x86/kernel/topology.c @@ -154,11 +154,6 @@ static int __init topology_init(void) { int i; -#ifdef CONFIG_NUMA - for_each_online_node(i) - register_one_node(i); -#endif - for_each_present_cpu(i) arch_register_cpu(i); diff --git a/drivers/base/init.c b/drivers/base/init.c index a9f57c22fb9e..d8d0fe687111 100644 --- a/drivers/base/init.c +++ b/drivers/base/init.c @@ -35,5 +35,6 @@ void __init driver_init(void) auxiliary_bus_init(); cpu_dev_init(); memory_dev_init(); + node_dev_init(); container_dev_init(); } diff --git a/drivers/base/node.c b/drivers/base/node.c index 87acc47e8951..a133981a12fc 100644 --- a/drivers/base/node.c +++ b/drivers/base/node.c @@ -1065,26 +1065,30 @@ static const struct attribute_group *cpu_root_attr_groups[] = { }; #define NODE_CALLBACK_PRI 2 /* lower than SLAB */ -static int __init register_node_type(void) +void __init node_dev_init(void) { - int ret; + static struct notifier_block node_memory_callback_nb = { + .notifier_call = node_memory_callback, + .priority = NODE_CALLBACK_PRI, + }; + int ret, i; BUILD_BUG_ON(ARRAY_SIZE(node_state_attr) != NR_NODE_STATES); BUILD_BUG_ON(ARRAY_SIZE(node_state_attrs)-1 != NR_NODE_STATES); ret = subsys_system_register(&node_subsys, cpu_root_attr_groups); - if (!ret) { - static struct notifier_block node_memory_callback_nb = { - .notifier_call = node_memory_callback, - .priority = NODE_CALLBACK_PRI, - }; - register_hotmemory_notifier(&node_memory_callback_nb); - } + if (ret) + panic("%s() failed to register subsystem: %d\n", __func__, ret); + + register_hotmemory_notifier(&node_memory_callback_nb); /* - * Note: we're not going to unregister the node class if we fail - * to register the node state class attribute files. + * Create all node devices, which will properly link the node + * to applicable memory block devices and already created cpu devices. */ - return ret; + for_each_online_node(i) { + ret = register_one_node(i); + if (ret) + panic("%s() failed to add node: %d\n", __func__, ret); + } } -postcore_initcall(register_node_type); diff --git a/include/linux/node.h b/include/linux/node.h index 81bbf1c0afd3..7f876d48af11 100644 --- a/include/linux/node.h +++ b/include/linux/node.h @@ -112,6 +112,7 @@ static inline void link_mem_sections(int nid, unsigned long start_pfn, extern void unregister_node(struct node *node); #ifdef CONFIG_NUMA +extern void node_dev_init(void); /* Core of the node registration - only memory hotplug should use this */ extern int __register_one_node(int nid); @@ -149,6 +150,9 @@ extern void register_hugetlbfs_with_node(node_registration_func_t doregister, node_registration_func_t unregister); #endif #else +static inline void node_dev_init(void) +{ +} static inline int __register_one_node(int nid) { return 0; -- cgit v1.2.3 From cc6515591b25f08ce199e9379844a964f52a27f2 Mon Sep 17 00:00:00 2001 From: David Hildenbrand Date: Tue, 22 Mar 2022 14:47:28 -0700 Subject: drivers/base/node: rename link_mem_sections() to register_memory_block_under_node() Patch series "drivers/base/memory: determine and store zone for single-zone memory blocks", v2. I remember talking to Michal in the past about removing test_pages_in_a_zone(), which we use for: * verifying that a memory block we intend to offline is really only managed by a single zone. We don't support offlining of memory blocks that are managed by multiple zones (e.g., multiple nodes, DMA and DMA32) * exposing that zone to user space via /sys/devices/system/memory/memory*/valid_zones Now that I identified some more cases where test_pages_in_a_zone() might go wrong, and we received an UBSAN report (see patch #3), let's get rid of this PFN walker. So instead of detecting the zone at runtime with test_pages_in_a_zone() by scanning the memmap, let's determine and remember for each memory block if it's managed by a single zone. The stored zone can then be used for the above two cases, avoiding a manual lookup using test_pages_in_a_zone(). This avoids eventually stumbling over uninitialized memmaps in corner cases, especially when ZONE_DEVICE ranges partly fall into memory block (that are responsible for managing System RAM). Handling memory onlining is easy, because we online to exactly one zone. Handling boot memory is more tricky, because we want to avoid scanning all zones of all nodes to detect possible zones that overlap with the physical memory region of interest. Fortunately, we already have code that determines the applicable nodes for a memory block, to create sysfs links -- we'll hook into that. Patch #1 is a simple cleanup I had laying around for a longer time. Patch #2 contains the main logic to remove test_pages_in_a_zone() and further details. [1] https://lkml.kernel.org/r/20220128144540.153902-1-david@redhat.com [2] https://lkml.kernel.org/r/20220203105212.30385-1-david@redhat.com This patch (of 2): Let's adjust the stale terminology, making it match unregister_memory_block_under_nodes() and do_register_memory_block_under_node(). We're dealing with memory block devices, which span 1..X memory sections. Link: https://lkml.kernel.org/r/20220210184359.235565-1-david@redhat.com Link: https://lkml.kernel.org/r/20220210184359.235565-2-david@redhat.com Signed-off-by: David Hildenbrand Acked-by: Oscar Salvador Cc: Greg Kroah-Hartman Cc: Michal Hocko Cc: "Rafael J. Wysocki" Cc: Rafael Parra Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/base/node.c | 5 +++-- include/linux/node.h | 16 ++++++++-------- mm/memory_hotplug.c | 6 +++--- 3 files changed, 14 insertions(+), 13 deletions(-) (limited to 'include/linux') diff --git a/drivers/base/node.c b/drivers/base/node.c index a133981a12fc..5d75341413ce 100644 --- a/drivers/base/node.c +++ b/drivers/base/node.c @@ -892,8 +892,9 @@ void unregister_memory_block_under_nodes(struct memory_block *mem_blk) kobject_name(&node_devices[mem_blk->nid]->dev.kobj)); } -void link_mem_sections(int nid, unsigned long start_pfn, unsigned long end_pfn, - enum meminit_context context) +void register_memory_blocks_under_node(int nid, unsigned long start_pfn, + unsigned long end_pfn, + enum meminit_context context) { walk_memory_blocks_func_t func; diff --git a/include/linux/node.h b/include/linux/node.h index 7f876d48af11..40d641a8bfb0 100644 --- a/include/linux/node.h +++ b/include/linux/node.h @@ -99,13 +99,13 @@ extern struct node *node_devices[]; typedef void (*node_registration_func_t)(struct node *); #if defined(CONFIG_MEMORY_HOTPLUG) && defined(CONFIG_NUMA) -void link_mem_sections(int nid, unsigned long start_pfn, - unsigned long end_pfn, - enum meminit_context context); +void register_memory_blocks_under_node(int nid, unsigned long start_pfn, + unsigned long end_pfn, + enum meminit_context context); #else -static inline void link_mem_sections(int nid, unsigned long start_pfn, - unsigned long end_pfn, - enum meminit_context context) +static inline void register_memory_blocks_under_node(int nid, unsigned long start_pfn, + unsigned long end_pfn, + enum meminit_context context) { } #endif @@ -129,8 +129,8 @@ static inline int register_one_node(int nid) error = __register_one_node(nid); if (error) return error; - /* link memory sections under this node */ - link_mem_sections(nid, start_pfn, end_pfn, MEMINIT_EARLY); + register_memory_blocks_under_node(nid, start_pfn, end_pfn, + MEMINIT_EARLY); } return error; diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index ce68098832aa..ed1a5dac6797 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -1383,9 +1383,9 @@ int __ref add_memory_resource(int nid, struct resource *res, mhp_t mhp_flags) BUG_ON(ret); } - /* link memory sections under this node.*/ - link_mem_sections(nid, PFN_DOWN(start), PFN_UP(start + size - 1), - MEMINIT_HOTPLUG); + register_memory_blocks_under_node(nid, PFN_DOWN(start), + PFN_UP(start + size - 1), + MEMINIT_HOTPLUG); /* create new memmap entry */ if (!strcmp(res->name, "System RAM")) -- cgit v1.2.3 From 395f6081bad49f9c54abafebab49ee23aa985bbd Mon Sep 17 00:00:00 2001 From: David Hildenbrand Date: Tue, 22 Mar 2022 14:47:31 -0700 Subject: drivers/base/memory: determine and store zone for single-zone memory blocks test_pages_in_a_zone() is just another nasty PFN walker that can easily stumble over ZONE_DEVICE memory ranges falling into the same memory block as ordinary system RAM: the memmap of parts of these ranges might possibly be uninitialized. In fact, we observed (on an older kernel) with UBSAN: UBSAN: Undefined behaviour in ./include/linux/mm.h:1133:50 index 7 is out of range for type 'zone [5]' CPU: 121 PID: 35603 Comm: read_all Kdump: loaded Tainted: [...] Hardware name: Dell Inc. PowerEdge R7425/08V001, BIOS 1.12.2 11/15/2019 Call Trace: dump_stack+0x9a/0xf0 ubsan_epilogue+0x9/0x7a __ubsan_handle_out_of_bounds+0x13a/0x181 test_pages_in_a_zone+0x3c4/0x500 show_valid_zones+0x1fa/0x380 dev_attr_show+0x43/0xb0 sysfs_kf_seq_show+0x1c5/0x440 seq_read+0x49d/0x1190 vfs_read+0xff/0x300 ksys_read+0xb8/0x170 do_syscall_64+0xa5/0x4b0 entry_SYSCALL_64_after_hwframe+0x6a/0xdf RIP: 0033:0x7f01f4439b52 We seem to stumble over a memmap that contains a garbage zone id. While we could try inserting pfn_to_online_page() calls, it will just make memory offlining slower, because we use test_pages_in_a_zone() to make sure we're offlining pages that all belong to the same zone. Let's just get rid of this PFN walker and determine the single zone of a memory block -- if any -- for early memory blocks during boot. For memory onlining, we know the single zone already. Let's avoid any additional memmap scanning and just rely on the zone information available during boot. For memory hot(un)plug, we only really care about memory blocks that: * span a single zone (and, thereby, a single node) * are completely System RAM (IOW, no holes, no ZONE_DEVICE) If one of these conditions is not met, we reject memory offlining. Hotplugged memory blocks (starting out offline), always meet both conditions. There are three scenarios to handle: (1) Memory hot(un)plug A memory block with zone == NULL cannot be offlined, corresponding to our previous test_pages_in_a_zone() check. After successful memory onlining/offlining, we simply set the zone accordingly. * Memory onlining: set the zone we just used for onlining * Memory offlining: set zone = NULL So a hotplugged memory block starts with zone = NULL. Once memory onlining is done, we set the proper zone. (2) Boot memory with !CONFIG_NUMA We know that there is just a single pgdat, so we simply scan all zones of that pgdat for an intersection with our memory block PFN range when adding the memory block. If more than one zone intersects (e.g., DMA and DMA32 on x86 for the first memory block) we set zone = NULL and consequently mimic what test_pages_in_a_zone() used to do. (3) Boot memory with CONFIG_NUMA At the point in time we create the memory block devices during boot, we don't know yet which nodes *actually* span a memory block. While we could scan all zones of all nodes for intersections, overlapping nodes complicate the situation and scanning all nodes is possibly expensive. But that problem has already been solved by the code that sets the node of a memory block and creates the link in the sysfs -- do_register_memory_block_under_node(). So, we hook into the code that sets the node id for a memory block. If we already have a different node id set for the memory block, we know that multiple nodes *actually* have PFNs falling into our memory block: we set zone = NULL and consequently mimic what test_pages_in_a_zone() used to do. If there is no node id set, we do the same as (2) for the given node. Note that the call order in driver_init() is: -> memory_dev_init(): create memory block devices -> node_dev_init(): link memory block devices to the node and set the node id So in summary, we detect if there is a single zone responsible for this memory block and we consequently store the zone in that case in the memory block, updating it during memory onlining/offlining. Link: https://lkml.kernel.org/r/20220210184359.235565-3-david@redhat.com Signed-off-by: David Hildenbrand Reported-by: Rafael Parra Reviewed-by: Oscar Salvador Cc: "Rafael J. Wysocki" Cc: Greg Kroah-Hartman Cc: Michal Hocko Cc: Rafael Parra Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/base/memory.c | 101 +++++++++++++++++++++++++++++++++++++++-- drivers/base/node.c | 13 ++---- include/linux/memory.h | 12 +++++ include/linux/memory_hotplug.h | 6 +-- mm/memory_hotplug.c | 50 ++++---------------- 5 files changed, 125 insertions(+), 57 deletions(-) (limited to 'include/linux') diff --git a/drivers/base/memory.c b/drivers/base/memory.c index 6ee2181adc3f..f75e3467cb59 100644 --- a/drivers/base/memory.c +++ b/drivers/base/memory.c @@ -215,6 +215,7 @@ static int memory_block_online(struct memory_block *mem) adjust_present_page_count(pfn_to_page(start_pfn), mem->group, nr_vmemmap_pages); + mem->zone = zone; return ret; } @@ -225,6 +226,9 @@ static int memory_block_offline(struct memory_block *mem) unsigned long nr_vmemmap_pages = mem->nr_vmemmap_pages; int ret; + if (!mem->zone) + return -EINVAL; + /* * Unaccount before offlining, such that unpopulated zone and kthreads * can properly be torn down in offline_pages(). @@ -234,7 +238,7 @@ static int memory_block_offline(struct memory_block *mem) -nr_vmemmap_pages); ret = offline_pages(start_pfn + nr_vmemmap_pages, - nr_pages - nr_vmemmap_pages, mem->group); + nr_pages - nr_vmemmap_pages, mem->zone, mem->group); if (ret) { /* offline_pages() failed. Account back. */ if (nr_vmemmap_pages) @@ -246,6 +250,7 @@ static int memory_block_offline(struct memory_block *mem) if (nr_vmemmap_pages) mhp_deinit_memmap_on_memory(start_pfn, nr_vmemmap_pages); + mem->zone = NULL; return ret; } @@ -411,11 +416,10 @@ static ssize_t valid_zones_show(struct device *dev, */ if (mem->state == MEM_ONLINE) { /* - * The block contains more than one zone can not be offlined. - * This can happen e.g. for ZONE_DMA and ZONE_DMA32 + * If !mem->zone, the memory block spans multiple zones and + * cannot get offlined. */ - default_zone = test_pages_in_a_zone(start_pfn, - start_pfn + nr_pages); + default_zone = mem->zone; if (!default_zone) return sysfs_emit(buf, "%s\n", "none"); len += sysfs_emit_at(buf, len, "%s", default_zone->name); @@ -643,6 +647,82 @@ int register_memory(struct memory_block *memory) return ret; } +static struct zone *early_node_zone_for_memory_block(struct memory_block *mem, + int nid) +{ + const unsigned long start_pfn = section_nr_to_pfn(mem->start_section_nr); + const unsigned long nr_pages = PAGES_PER_SECTION * sections_per_block; + struct zone *zone, *matching_zone = NULL; + pg_data_t *pgdat = NODE_DATA(nid); + int i; + + /* + * This logic only works for early memory, when the applicable zones + * already span the memory block. We don't expect overlapping zones on + * a single node for early memory. So if we're told that some PFNs + * of a node fall into this memory block, we can assume that all node + * zones that intersect with the memory block are actually applicable. + * No need to look at the memmap. + */ + for (i = 0; i < MAX_NR_ZONES; i++) { + zone = pgdat->node_zones + i; + if (!populated_zone(zone)) + continue; + if (!zone_intersects(zone, start_pfn, nr_pages)) + continue; + if (!matching_zone) { + matching_zone = zone; + continue; + } + /* Spans multiple zones ... */ + matching_zone = NULL; + break; + } + return matching_zone; +} + +#ifdef CONFIG_NUMA +/** + * memory_block_add_nid() - Indicate that system RAM falling into this memory + * block device (partially) belongs to the given node. + * @mem: The memory block device. + * @nid: The node id. + * @context: The memory initialization context. + * + * Indicate that system RAM falling into this memory block (partially) belongs + * to the given node. If the context indicates ("early") that we are adding the + * node during node device subsystem initialization, this will also properly + * set/adjust mem->zone based on the zone ranges of the given node. + */ +void memory_block_add_nid(struct memory_block *mem, int nid, + enum meminit_context context) +{ + if (context == MEMINIT_EARLY && mem->nid != nid) { + /* + * For early memory we have to determine the zone when setting + * the node id and handle multiple nodes spanning a single + * memory block by indicate via zone == NULL that we're not + * dealing with a single zone. So if we're setting the node id + * the first time, determine if there is a single zone. If we're + * setting the node id a second time to a different node, + * invalidate the single detected zone. + */ + if (mem->nid == NUMA_NO_NODE) + mem->zone = early_node_zone_for_memory_block(mem, nid); + else + mem->zone = NULL; + } + + /* + * If this memory block spans multiple nodes, we only indicate + * the last processed node. If we span multiple nodes (not applicable + * to hotplugged memory), zone == NULL will prohibit memory offlining + * and consequently unplug. + */ + mem->nid = nid; +} +#endif + static int init_memory_block(unsigned long block_id, unsigned long state, unsigned long nr_vmemmap_pages, struct memory_group *group) @@ -665,6 +745,17 @@ static int init_memory_block(unsigned long block_id, unsigned long state, mem->nr_vmemmap_pages = nr_vmemmap_pages; INIT_LIST_HEAD(&mem->group_next); +#ifndef CONFIG_NUMA + if (state == MEM_ONLINE) + /* + * MEM_ONLINE at this point implies early memory. With NUMA, + * we'll determine the zone when setting the node id via + * memory_block_add_nid(). Memory hotplug updated the zone + * manually when memory onlining/offlining succeeds. + */ + mem->zone = early_node_zone_for_memory_block(mem, NUMA_NO_NODE); +#endif /* CONFIG_NUMA */ + ret = register_memory(mem); if (ret) return ret; diff --git a/drivers/base/node.c b/drivers/base/node.c index 5d75341413ce..ec8bb24a5a22 100644 --- a/drivers/base/node.c +++ b/drivers/base/node.c @@ -796,15 +796,12 @@ static int __ref get_nid_for_pfn(unsigned long pfn) } static void do_register_memory_block_under_node(int nid, - struct memory_block *mem_blk) + struct memory_block *mem_blk, + enum meminit_context context) { int ret; - /* - * If this memory block spans multiple nodes, we only indicate - * the last processed node. - */ - mem_blk->nid = nid; + memory_block_add_nid(mem_blk, nid, context); ret = sysfs_create_link_nowarn(&node_devices[nid]->dev.kobj, &mem_blk->dev.kobj, @@ -857,7 +854,7 @@ static int register_mem_block_under_node_early(struct memory_block *mem_blk, if (page_nid != nid) continue; - do_register_memory_block_under_node(nid, mem_blk); + do_register_memory_block_under_node(nid, mem_blk, MEMINIT_EARLY); return 0; } /* mem section does not span the specified node */ @@ -873,7 +870,7 @@ static int register_mem_block_under_node_hotplug(struct memory_block *mem_blk, { int nid = *(int *)arg; - do_register_memory_block_under_node(nid, mem_blk); + do_register_memory_block_under_node(nid, mem_blk, MEMINIT_HOTPLUG); return 0; } diff --git a/include/linux/memory.h b/include/linux/memory.h index 88eb587b5143..aa619464a1df 100644 --- a/include/linux/memory.h +++ b/include/linux/memory.h @@ -70,6 +70,13 @@ struct memory_block { unsigned long state; /* serialized by the dev->lock */ int online_type; /* for passing data to online routine */ int nid; /* NID for this memory block */ + /* + * The single zone of this memory block if all PFNs of this memory block + * that are System RAM (not a memory hole, not ZONE_DEVICE ranges) are + * managed by a single zone. NULL if multiple zones (including nodes) + * apply. + */ + struct zone *zone; struct device dev; /* * Number of vmemmap pages. These pages @@ -161,6 +168,11 @@ int walk_dynamic_memory_groups(int nid, walk_memory_groups_func_t func, }) #define register_hotmemory_notifier(nb) register_memory_notifier(nb) #define unregister_hotmemory_notifier(nb) unregister_memory_notifier(nb) + +#ifdef CONFIG_NUMA +void memory_block_add_nid(struct memory_block *mem, int nid, + enum meminit_context context); +#endif /* CONFIG_NUMA */ #endif /* CONFIG_MEMORY_HOTPLUG */ /* diff --git a/include/linux/memory_hotplug.h b/include/linux/memory_hotplug.h index 76bf2de86def..1ce6f8044f1e 100644 --- a/include/linux/memory_hotplug.h +++ b/include/linux/memory_hotplug.h @@ -163,8 +163,6 @@ extern int mhp_init_memmap_on_memory(unsigned long pfn, unsigned long nr_pages, extern void mhp_deinit_memmap_on_memory(unsigned long pfn, unsigned long nr_pages); extern int online_pages(unsigned long pfn, unsigned long nr_pages, struct zone *zone, struct memory_group *group); -extern struct zone *test_pages_in_a_zone(unsigned long start_pfn, - unsigned long end_pfn); extern void __offline_isolated_pages(unsigned long start_pfn, unsigned long end_pfn); @@ -293,7 +291,7 @@ static inline void pgdat_resize_init(struct pglist_data *pgdat) {} extern void try_offline_node(int nid); extern int offline_pages(unsigned long start_pfn, unsigned long nr_pages, - struct memory_group *group); + struct zone *zone, struct memory_group *group); extern int remove_memory(u64 start, u64 size); extern void __remove_memory(u64 start, u64 size); extern int offline_and_remove_memory(u64 start, u64 size); @@ -302,7 +300,7 @@ extern int offline_and_remove_memory(u64 start, u64 size); static inline void try_offline_node(int nid) {} static inline int offline_pages(unsigned long start_pfn, unsigned long nr_pages, - struct memory_group *group) + struct zone *zone, struct memory_group *group) { return -EINVAL; } diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index ed1a5dac6797..aee69281dad6 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -1548,38 +1548,6 @@ bool mhp_range_allowed(u64 start, u64 size, bool need_mapping) } #ifdef CONFIG_MEMORY_HOTREMOVE -/* - * Confirm all pages in a range [start, end) belong to the same zone (skipping - * memory holes). When true, return the zone. - */ -struct zone *test_pages_in_a_zone(unsigned long start_pfn, - unsigned long end_pfn) -{ - unsigned long pfn, sec_end_pfn; - struct zone *zone = NULL; - struct page *page; - - for (pfn = start_pfn, sec_end_pfn = SECTION_ALIGN_UP(start_pfn + 1); - pfn < end_pfn; - pfn = sec_end_pfn, sec_end_pfn += PAGES_PER_SECTION) { - /* Make sure the memory section is present first */ - if (!present_section_nr(pfn_to_section_nr(pfn))) - continue; - for (; pfn < sec_end_pfn && pfn < end_pfn; - pfn += MAX_ORDER_NR_PAGES) { - /* Check if we got outside of the zone */ - if (zone && !zone_spans_pfn(zone, pfn)) - return NULL; - page = pfn_to_page(pfn); - if (zone && page_zone(page) != zone) - return NULL; - zone = page_zone(page); - } - } - - return zone; -} - /* * Scan pfn range [start,end) to find movable/migratable pages (LRU pages, * non-lru movable pages and hugepages). Will skip over most unmovable @@ -1803,15 +1771,15 @@ static int count_system_ram_pages_cb(unsigned long start_pfn, } int __ref offline_pages(unsigned long start_pfn, unsigned long nr_pages, - struct memory_group *group) + struct zone *zone, struct memory_group *group) { const unsigned long end_pfn = start_pfn + nr_pages; unsigned long pfn, system_ram_pages = 0; + const int node = zone_to_nid(zone); unsigned long flags; - struct zone *zone; struct memory_notify arg; - int ret, node; char *reason; + int ret; /* * {on,off}lining is constrained to full memory sections (or more @@ -1843,15 +1811,17 @@ int __ref offline_pages(unsigned long start_pfn, unsigned long nr_pages, goto failed_removal; } - /* This makes hotplug much easier...and readable. - we assume this for now. .*/ - zone = test_pages_in_a_zone(start_pfn, end_pfn); - if (!zone) { + /* + * We only support offlining of memory blocks managed by a single zone, + * checked by calling code. This is just a sanity check that we might + * want to remove in the future. + */ + if (WARN_ON_ONCE(page_zone(pfn_to_page(start_pfn)) != zone || + page_zone(pfn_to_page(end_pfn - 1)) != zone)) { ret = -EINVAL; reason = "multizone range"; goto failed_removal; } - node = zone_to_nid(zone); /* * Disable pcplists so that page isolation cannot race with freeing -- cgit v1.2.3 From 734c15700cdf9062ae98d8b131c6fe873dfad26d Mon Sep 17 00:00:00 2001 From: Oscar Salvador Date: Tue, 22 Mar 2022 14:47:37 -0700 Subject: mm: only re-generate demotion targets when a numa node changes its N_CPU state Abhishek reported that after patch [1], hotplug operations are taking roughly double the expected time. [2] The reason behind is that the CPU callbacks that migrate_on_reclaim_init() sets always call set_migration_target_nodes() whenever a CPU is brought up/down. But we only care about numa nodes going from having cpus to become cpuless, and vice versa, as that influences the demotion_target order. We do already have two CPU callbacks (vmstat_cpu_online() and vmstat_cpu_dead()) that check exactly that, so get rid of the CPU callbacks in migrate_on_reclaim_init() and only call set_migration_target_nodes() from vmstat_cpu_{dead,online}() whenever a numa node change its N_CPU state. [1] https://lore.kernel.org/linux-mm/20210721063926.3024591-2-ying.huang@intel.com/ [2] https://lore.kernel.org/linux-mm/eb438ddd-2919-73d4-bd9f-b7eecdd9577a@linux.vnet.ibm.com/ [osalvador@suse.de: add feedback from Huang Ying] Link: https://lkml.kernel.org/r/20220314150945.12694-1-osalvador@suse.de Link: https://lkml.kernel.org/r/20220310120749.23077-1-osalvador@suse.de Fixes: 884a6e5d1f93b ("mm/migrate: update node demotion order on hotplug events") Signed-off-by: Oscar Salvador Reviewed-by: Baolin Wang Tested-by: Baolin Wang Reported-by: Abhishek Goel Cc: Dave Hansen Cc: "Huang, Ying" Cc: Abhishek Goel Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/migrate.h | 8 ++++++++ mm/migrate.c | 47 ++++++++++------------------------------------- mm/vmstat.c | 13 ++++++++++++- 3 files changed, 30 insertions(+), 38 deletions(-) (limited to 'include/linux') diff --git a/include/linux/migrate.h b/include/linux/migrate.h index db96e10eb8da..90e75d5a54d6 100644 --- a/include/linux/migrate.h +++ b/include/linux/migrate.h @@ -48,7 +48,15 @@ int folio_migrate_mapping(struct address_space *mapping, struct folio *newfolio, struct folio *folio, int extra_count); extern bool numa_demotion_enabled; +extern void migrate_on_reclaim_init(void); +#ifdef CONFIG_HOTPLUG_CPU +extern void set_migration_target_nodes(void); #else +static inline void set_migration_target_nodes(void) {} +#endif +#else + +static inline void set_migration_target_nodes(void) {} static inline void putback_movable_pages(struct list_head *l) {} static inline int migrate_pages(struct list_head *l, new_page_t new, diff --git a/mm/migrate.c b/mm/migrate.c index 78b2cf87946d..bc9da3fd01aa 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -3209,7 +3209,7 @@ again: /* * For callers that do not hold get_online_mems() already. */ -static void set_migration_target_nodes(void) +void set_migration_target_nodes(void) { get_online_mems(); __set_migration_target_nodes(); @@ -3273,51 +3273,24 @@ static int __meminit migrate_on_reclaim_callback(struct notifier_block *self, return notifier_from_errno(0); } -/* - * React to hotplug events that might affect the migration targets - * like events that online or offline NUMA nodes. - * - * The ordering is also currently dependent on which nodes have - * CPUs. That means we need CPU on/offline notification too. - */ -static int migration_online_cpu(unsigned int cpu) -{ - set_migration_target_nodes(); - return 0; -} - -static int migration_offline_cpu(unsigned int cpu) +void __init migrate_on_reclaim_init(void) { - set_migration_target_nodes(); - return 0; -} - -static int __init migrate_on_reclaim_init(void) -{ - int ret; - node_demotion = kmalloc_array(nr_node_ids, sizeof(struct demotion_nodes), GFP_KERNEL); WARN_ON(!node_demotion); - ret = cpuhp_setup_state_nocalls(CPUHP_MM_DEMOTION_DEAD, "mm/demotion:offline", - NULL, migration_offline_cpu); + hotplug_memory_notifier(migrate_on_reclaim_callback, 100); /* - * In the unlikely case that this fails, the automatic - * migration targets may become suboptimal for nodes - * where N_CPU changes. With such a small impact in a - * rare case, do not bother trying to do anything special. + * At this point, all numa nodes with memory/CPus have their state + * properly set, so we can build the demotion order now. + * Let us hold the cpu_hotplug lock just, as we could possibily have + * CPU hotplug events during boot. */ - WARN_ON(ret < 0); - ret = cpuhp_setup_state(CPUHP_AP_MM_DEMOTION_ONLINE, "mm/demotion:online", - migration_online_cpu, NULL); - WARN_ON(ret < 0); - - hotplug_memory_notifier(migrate_on_reclaim_callback, 100); - return 0; + cpus_read_lock(); + set_migration_target_nodes(); + cpus_read_unlock(); } -late_initcall(migrate_on_reclaim_init); #endif /* CONFIG_HOTPLUG_CPU */ bool numa_demotion_enabled = false; diff --git a/mm/vmstat.c b/mm/vmstat.c index d5cc8d739fac..b75b1a64b54c 100644 --- a/mm/vmstat.c +++ b/mm/vmstat.c @@ -28,6 +28,7 @@ #include #include #include +#include #include "internal.h" @@ -2049,7 +2050,12 @@ static void __init init_cpu_node_state(void) static int vmstat_cpu_online(unsigned int cpu) { refresh_zone_stat_thresholds(); - node_set_state(cpu_to_node(cpu), N_CPU); + + if (!node_state(cpu_to_node(cpu), N_CPU)) { + node_set_state(cpu_to_node(cpu), N_CPU); + set_migration_target_nodes(); + } + return 0; } @@ -2072,6 +2078,8 @@ static int vmstat_cpu_dead(unsigned int cpu) return 0; node_clear_state(node, N_CPU); + set_migration_target_nodes(); + return 0; } @@ -2103,6 +2111,9 @@ void __init init_mm_internals(void) start_shepherd_timer(); #endif +#if defined(CONFIG_MIGRATION) && defined(CONFIG_HOTPLUG_CPU) + migrate_on_reclaim_init(); +#endif #ifdef CONFIG_PROC_FS proc_create_seq("buddyinfo", 0444, NULL, &fragmentation_op); proc_create_seq("pagetypeinfo", 0400, NULL, &pagetypeinfo_op); -- cgit v1.2.3 From 6eada26ffc80bfe1f2db088be0c44ec82b5cd3dc Mon Sep 17 00:00:00 2001 From: Christophe Leroy Date: Tue, 22 Mar 2022 14:47:46 -0700 Subject: mm: remove usercopy_warn() Users of usercopy_warn() were removed by commit 53944f171a89 ("mm: remove HARDENED_USERCOPY_FALLBACK") Remove it. Link: https://lkml.kernel.org/r/5f26643fc70b05f8455b60b99c30c17d635fa640.1644231910.git.christophe.leroy@csgroup.eu Signed-off-by: Christophe Leroy Reviewed-by: Miaohe Lin Reviewed-by: Stephen Kitt Reviewed-by: Muchun Song Cc: Kees Cook Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/uaccess.h | 2 -- mm/usercopy.c | 11 ----------- 2 files changed, 13 deletions(-) (limited to 'include/linux') diff --git a/include/linux/uaccess.h b/include/linux/uaccess.h index ac0394087f7d..bca27b4e5eb2 100644 --- a/include/linux/uaccess.h +++ b/include/linux/uaccess.h @@ -401,8 +401,6 @@ static inline void user_access_restore(unsigned long flags) { } #endif #ifdef CONFIG_HARDENED_USERCOPY -void usercopy_warn(const char *name, const char *detail, bool to_user, - unsigned long offset, unsigned long len); void __noreturn usercopy_abort(const char *name, const char *detail, bool to_user, unsigned long offset, unsigned long len); diff --git a/mm/usercopy.c b/mm/usercopy.c index d0d268135d96..e7b0cb49daa1 100644 --- a/mm/usercopy.c +++ b/mm/usercopy.c @@ -70,17 +70,6 @@ static noinline int check_stack_object(const void *obj, unsigned long len) * kmem_cache_create_usercopy() function to create the cache (and * carefully audit the whitelist range). */ -void usercopy_warn(const char *name, const char *detail, bool to_user, - unsigned long offset, unsigned long len) -{ - WARN_ONCE(1, "Bad or missing usercopy whitelist? Kernel memory %s attempt detected %s %s%s%s%s (offset %lu, size %lu)!\n", - to_user ? "exposure" : "overwrite", - to_user ? "from" : "to", - name ? : "unknown?!", - detail ? " '" : "", detail ? : "", detail ? "'" : "", - offset, len); -} - void __noreturn usercopy_abort(const char *name, const char *detail, bool to_user, unsigned long offset, unsigned long len) -- cgit v1.2.3 From ad7489d5262d2aa775b5e5a1782793925fa90065 Mon Sep 17 00:00:00 2001 From: Christophe Leroy Date: Tue, 22 Mar 2022 14:47:49 -0700 Subject: mm: uninline copy_overflow() While building a small config with CONFIG_CC_OPTIMISE_FOR_SIZE, I ended up with more than 50 times the following function in vmlinux because GCC doesn't honor the 'inline' keyword: c00243bc : c00243bc: 94 21 ff f0 stwu r1,-16(r1) c00243c0: 7c 85 23 78 mr r5,r4 c00243c4: 7c 64 1b 78 mr r4,r3 c00243c8: 3c 60 c0 62 lis r3,-16286 c00243cc: 7c 08 02 a6 mflr r0 c00243d0: 38 63 5e e5 addi r3,r3,24293 c00243d4: 90 01 00 14 stw r0,20(r1) c00243d8: 4b ff 82 45 bl c001c61c <__warn_printk> c00243dc: 0f e0 00 00 twui r0,0 c00243e0: 80 01 00 14 lwz r0,20(r1) c00243e4: 38 21 00 10 addi r1,r1,16 c00243e8: 7c 08 03 a6 mtlr r0 c00243ec: 4e 80 00 20 blr With -Winline, GCC tells: /include/linux/thread_info.h:212:20: warning: inlining failed in call to 'copy_overflow': call is unlikely and code size would grow [-Winline] copy_overflow() is a non conditional warning called by check_copy_size() on an error path. check_copy_size() have to remain inlined in order to benefit from constant folding, but copy_overflow() is not worth inlining. Uninline the warning when CONFIG_BUG is selected. When CONFIG_BUG is not selected, WARN() does nothing so skip it. This reduces the size of vmlinux by almost 4kbytes. Link: https://lkml.kernel.org/r/e1723b9cfa924bcefcd41f69d0025b38e4c9364e.1644819985.git.christophe.leroy@csgroup.eu Signed-off-by: Christophe Leroy Cc: David Laight Cc: Anshuman Khandual Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/thread_info.h | 5 ++++- mm/maccess.c | 6 ++++++ 2 files changed, 10 insertions(+), 1 deletion(-) (limited to 'include/linux') diff --git a/include/linux/thread_info.h b/include/linux/thread_info.h index 73a6f34b3847..9f392ec76f2b 100644 --- a/include/linux/thread_info.h +++ b/include/linux/thread_info.h @@ -209,9 +209,12 @@ __bad_copy_from(void); extern void __compiletime_error("copy destination size is too small") __bad_copy_to(void); +void __copy_overflow(int size, unsigned long count); + static inline void copy_overflow(int size, unsigned long count) { - WARN(1, "Buffer overflow detected (%d < %lu)!\n", size, count); + if (IS_ENABLED(CONFIG_BUG)) + __copy_overflow(size, count); } static __always_inline __must_check bool diff --git a/mm/maccess.c b/mm/maccess.c index d3f1a1f0b1c1..3fed2b876539 100644 --- a/mm/maccess.c +++ b/mm/maccess.c @@ -335,3 +335,9 @@ long strnlen_user_nofault(const void __user *unsafe_addr, long count) return ret; } + +void __copy_overflow(int size, unsigned long count) +{ + WARN(1, "Buffer overflow detected (%d < %lu)!\n", size, count); +} +EXPORT_SYMBOL(__copy_overflow); -- cgit v1.2.3 From d7ca25c53e25a9a628aaa19b5a031f115d8c353d Mon Sep 17 00:00:00 2001 From: Ira Weiny Date: Tue, 22 Mar 2022 14:47:58 -0700 Subject: highmem: document kunmap_local() Some users of kmap() add an offset to the kmap() address to be used during the mapping. When converting to kmap_local_page() the base address does not need to be stored because any address within the page can be used in kunmap_local(). However, this was not clear from the documentation and cause some questions.[1] Document that any address in the page can be used in kunmap_local() to clarify this for future users. [1] https://lore.kernel.org/lkml/20211213154543.GM3538886@iweiny-DESK2.sc.intel.com/ [ira.weiny@intel.com: updates per Christoph] Link: https://lkml.kernel.org/r/20220124182138.816693-1-ira.weiny@intel.com Link: https://lkml.kernel.org/r/20220124013045.806718-1-ira.weiny@intel.com Signed-off-by: Ira Weiny Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/highmem-internal.h | 10 ++++++++++ 1 file changed, 10 insertions(+) (limited to 'include/linux') diff --git a/include/linux/highmem-internal.h b/include/linux/highmem-internal.h index 0a0b2b09b1b8..a77be5630209 100644 --- a/include/linux/highmem-internal.h +++ b/include/linux/highmem-internal.h @@ -246,6 +246,16 @@ do { \ __kunmap_atomic(__addr); \ } while (0) +/** + * kunmap_local - Unmap a page mapped via kmap_local_page(). + * @__addr: An address within the page mapped + * + * @__addr can be any address within the mapped page. Commonly it is the + * address return from kmap_local_page(), but it can also include offsets. + * + * Unmapping should be done in the reverse order of the mapping. See + * kmap_local_page() for details. + */ #define kunmap_local(__addr) \ do { \ BUILD_BUG_ON(__same_type((__addr), struct page *)); \ -- cgit v1.2.3 From 436428255d5981e49ff015fc8e398ecf2ba10c24 Mon Sep 17 00:00:00 2001 From: SeongJae Park Date: Tue, 22 Mar 2022 14:48:37 -0700 Subject: mm/damon/core: move damon_set_targets() into dbgfs damon_set_targets() function is defined in the core for general use cases, but called from only dbgfs. Also, because the function is for general use cases, dbgfs does additional handling of pid type target id case. To make the situation simpler, this commit moves the function into dbgfs and makes it to do the pid type case handling on its own. Link: https://lkml.kernel.org/r/20211230100723.2238-4-sj@kernel.org Signed-off-by: SeongJae Park Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/damon.h | 2 -- mm/damon/core-test.h | 5 ++++- mm/damon/core.c | 32 ------------------------------- mm/damon/dbgfs-test.h | 14 +++++++------- mm/damon/dbgfs.c | 53 +++++++++++++++++++++++++++++++++++++++------------ 5 files changed, 52 insertions(+), 54 deletions(-) (limited to 'include/linux') diff --git a/include/linux/damon.h b/include/linux/damon.h index 5e1e3a128b77..bd021af5db3d 100644 --- a/include/linux/damon.h +++ b/include/linux/damon.h @@ -484,8 +484,6 @@ unsigned int damon_nr_regions(struct damon_target *t); struct damon_ctx *damon_new_ctx(void); void damon_destroy_ctx(struct damon_ctx *ctx); -int damon_set_targets(struct damon_ctx *ctx, - unsigned long *ids, ssize_t nr_ids); int damon_set_attrs(struct damon_ctx *ctx, unsigned long sample_int, unsigned long aggr_int, unsigned long primitive_upd_int, unsigned long min_nr_reg, unsigned long max_nr_reg); diff --git a/mm/damon/core-test.h b/mm/damon/core-test.h index 7008c3735e99..4a6141ddd6fc 100644 --- a/mm/damon/core-test.h +++ b/mm/damon/core-test.h @@ -86,7 +86,10 @@ static void damon_test_aggregate(struct kunit *test) struct damon_region *r; int it, ir; - damon_set_targets(ctx, target_ids, 3); + for (it = 0; it < 3; it++) { + t = damon_new_target(target_ids[it]); + damon_add_target(ctx, t); + } it = 0; damon_for_each_target(t, ctx) { diff --git a/mm/damon/core.c b/mm/damon/core.c index 1dd153c31c9e..3fef5c667a31 100644 --- a/mm/damon/core.c +++ b/mm/damon/core.c @@ -245,38 +245,6 @@ void damon_destroy_ctx(struct damon_ctx *ctx) kfree(ctx); } -/** - * damon_set_targets() - Set monitoring targets. - * @ctx: monitoring context - * @ids: array of target ids - * @nr_ids: number of entries in @ids - * - * This function should not be called while the kdamond is running. - * - * Return: 0 on success, negative error code otherwise. - */ -int damon_set_targets(struct damon_ctx *ctx, - unsigned long *ids, ssize_t nr_ids) -{ - ssize_t i; - struct damon_target *t, *next; - - damon_destroy_targets(ctx); - - for (i = 0; i < nr_ids; i++) { - t = damon_new_target(ids[i]); - if (!t) { - /* The caller should do cleanup of the ids itself */ - damon_for_each_target_safe(t, next, ctx) - damon_destroy_target(t); - return -ENOMEM; - } - damon_add_target(ctx, t); - } - - return 0; -} - /** * damon_set_attrs() - Set attributes for the monitoring. * @ctx: monitoring context diff --git a/mm/damon/dbgfs-test.h b/mm/damon/dbgfs-test.h index 00bff058fe08..c1c988b607bc 100644 --- a/mm/damon/dbgfs-test.h +++ b/mm/damon/dbgfs-test.h @@ -86,23 +86,23 @@ static void damon_dbgfs_test_set_targets(struct kunit *test) ctx->primitive.target_valid = NULL; ctx->primitive.cleanup = NULL; - damon_set_targets(ctx, ids, 3); + dbgfs_set_targets(ctx, ids, 3); sprint_target_ids(ctx, buf, 64); KUNIT_EXPECT_STREQ(test, (char *)buf, "1 2 3\n"); - damon_set_targets(ctx, NULL, 0); + dbgfs_set_targets(ctx, NULL, 0); sprint_target_ids(ctx, buf, 64); KUNIT_EXPECT_STREQ(test, (char *)buf, "\n"); - damon_set_targets(ctx, (unsigned long []){1, 2}, 2); + dbgfs_set_targets(ctx, (unsigned long []){1, 2}, 2); sprint_target_ids(ctx, buf, 64); KUNIT_EXPECT_STREQ(test, (char *)buf, "1 2\n"); - damon_set_targets(ctx, (unsigned long []){2}, 1); + dbgfs_set_targets(ctx, (unsigned long []){2}, 1); sprint_target_ids(ctx, buf, 64); KUNIT_EXPECT_STREQ(test, (char *)buf, "2\n"); - damon_set_targets(ctx, NULL, 0); + dbgfs_set_targets(ctx, NULL, 0); sprint_target_ids(ctx, buf, 64); KUNIT_EXPECT_STREQ(test, (char *)buf, "\n"); @@ -130,7 +130,7 @@ static void damon_dbgfs_test_set_init_regions(struct kunit *test) int i, rc; char buf[256]; - damon_set_targets(ctx, ids, 3); + dbgfs_set_targets(ctx, ids, 3); /* Put valid inputs and check the results */ for (i = 0; i < ARRAY_SIZE(valid_inputs); i++) { @@ -158,7 +158,7 @@ static void damon_dbgfs_test_set_init_regions(struct kunit *test) KUNIT_EXPECT_STREQ(test, (char *)buf, ""); } - damon_set_targets(ctx, NULL, 0); + dbgfs_set_targets(ctx, NULL, 0); damon_destroy_ctx(ctx); } diff --git a/mm/damon/dbgfs.c b/mm/damon/dbgfs.c index 3f65af04e4e6..58867b966635 100644 --- a/mm/damon/dbgfs.c +++ b/mm/damon/dbgfs.c @@ -358,11 +358,48 @@ static void dbgfs_put_pids(unsigned long *ids, int nr_ids) put_pid((struct pid *)ids[i]); } +/* + * dbgfs_set_targets() - Set monitoring targets. + * @ctx: monitoring context + * @ids: array of target ids + * @nr_ids: number of entries in @ids + * + * This function should not be called while the kdamond is running. + * + * Return: 0 on success, negative error code otherwise. + */ +static int dbgfs_set_targets(struct damon_ctx *ctx, + unsigned long *ids, ssize_t nr_ids) +{ + ssize_t i; + struct damon_target *t, *next; + + damon_for_each_target_safe(t, next, ctx) { + if (targetid_is_pid(ctx)) + put_pid((struct pid *)t->id); + damon_destroy_target(t); + } + + for (i = 0; i < nr_ids; i++) { + t = damon_new_target(ids[i]); + if (!t) { + /* The caller should do cleanup of the ids itself */ + damon_for_each_target_safe(t, next, ctx) + damon_destroy_target(t); + if (targetid_is_pid(ctx)) + dbgfs_put_pids(ids, nr_ids); + return -ENOMEM; + } + damon_add_target(ctx, t); + } + + return 0; +} + static ssize_t dbgfs_target_ids_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos) { struct damon_ctx *ctx = file->private_data; - struct damon_target *t, *next_t; bool id_is_pid = true; char *kbuf; unsigned long *targets; @@ -407,11 +444,7 @@ static ssize_t dbgfs_target_ids_write(struct file *file, } /* remove previously set targets */ - damon_for_each_target_safe(t, next_t, ctx) { - if (targetid_is_pid(ctx)) - put_pid((struct pid *)t->id); - damon_destroy_target(t); - } + dbgfs_set_targets(ctx, NULL, 0); /* Configure the context for the address space type */ if (id_is_pid) @@ -419,13 +452,9 @@ static ssize_t dbgfs_target_ids_write(struct file *file, else damon_pa_set_primitives(ctx); - ret = damon_set_targets(ctx, targets, nr_targets); - if (ret) { - if (id_is_pid) - dbgfs_put_pids(targets, nr_targets); - } else { + ret = dbgfs_set_targets(ctx, targets, nr_targets); + if (!ret) ret = count; - } unlock_out: mutex_unlock(&ctx->kdamond_lock); -- cgit v1.2.3 From 1971bd630452e943380429336a851c55b027eed1 Mon Sep 17 00:00:00 2001 From: SeongJae Park Date: Tue, 22 Mar 2022 14:48:40 -0700 Subject: mm/damon: remove the target id concept DAMON asks each monitoring target ('struct damon_target') to have one 'unsigned long' integer called 'id', which should be unique among the targets of same monitoring context. Meaning of it is, however, totally up to the monitoring primitives that registered to the monitoring context. For example, the virtual address spaces monitoring primitives treats the id as a 'struct pid' pointer. This makes the code flexible, but ugly, not well-documented, and type-unsafe[1]. Also, identification of each target can be done via its index. For the reason, this commit removes the concept and uses clear type definition. For now, only 'struct pid' pointer is used for the virtual address spaces monitoring. If DAMON is extended in future so that we need to put another identifier field in the struct, we will use a union for such primitives-dependent fields and document which primitives are using which type. [1] https://lore.kernel.org/linux-mm/20211013154535.4aaeaaf9d0182922e405dd1e@linux-foundation.org/ Link: https://lkml.kernel.org/r/20211230100723.2238-5-sj@kernel.org Signed-off-by: SeongJae Park Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/damon.h | 11 ++-- mm/damon/core-test.h | 18 +++--- mm/damon/core.c | 4 +- mm/damon/dbgfs-test.h | 63 ++++++++------------- mm/damon/dbgfs.c | 152 ++++++++++++++++++++++++++++++-------------------- mm/damon/reclaim.c | 3 +- mm/damon/vaddr-test.h | 6 +- mm/damon/vaddr.c | 4 +- 8 files changed, 133 insertions(+), 128 deletions(-) (limited to 'include/linux') diff --git a/include/linux/damon.h b/include/linux/damon.h index bd021af5db3d..7c1d915b3587 100644 --- a/include/linux/damon.h +++ b/include/linux/damon.h @@ -60,19 +60,18 @@ struct damon_region { /** * struct damon_target - Represents a monitoring target. - * @id: Unique identifier for this target. + * @pid: The PID of the virtual address space to monitor. * @nr_regions: Number of monitoring target regions of this target. * @regions_list: Head of the monitoring target regions of this target. * @list: List head for siblings. * * Each monitoring context could have multiple targets. For example, a context * for virtual memory address spaces could have multiple target processes. The - * @id of each target should be unique among the targets of the context. For - * example, in the virtual address monitoring context, it could be a pidfd or - * an address of an mm_struct. + * @pid should be set for appropriate address space monitoring primitives + * including the virtual address spaces monitoring primitives. */ struct damon_target { - unsigned long id; + struct pid *pid; unsigned int nr_regions; struct list_head regions_list; struct list_head list; @@ -475,7 +474,7 @@ struct damos *damon_new_scheme( void damon_add_scheme(struct damon_ctx *ctx, struct damos *s); void damon_destroy_scheme(struct damos *s); -struct damon_target *damon_new_target(unsigned long id); +struct damon_target *damon_new_target(void); void damon_add_target(struct damon_ctx *ctx, struct damon_target *t); bool damon_targets_empty(struct damon_ctx *ctx); void damon_free_target(struct damon_target *t); diff --git a/mm/damon/core-test.h b/mm/damon/core-test.h index 4a6141ddd6fc..b4085deb9fa0 100644 --- a/mm/damon/core-test.h +++ b/mm/damon/core-test.h @@ -24,7 +24,7 @@ static void damon_test_regions(struct kunit *test) KUNIT_EXPECT_EQ(test, 2ul, r->ar.end); KUNIT_EXPECT_EQ(test, 0u, r->nr_accesses); - t = damon_new_target(42); + t = damon_new_target(); KUNIT_EXPECT_EQ(test, 0u, damon_nr_regions(t)); damon_add_region(r, t); @@ -52,8 +52,7 @@ static void damon_test_target(struct kunit *test) struct damon_ctx *c = damon_new_ctx(); struct damon_target *t; - t = damon_new_target(42); - KUNIT_EXPECT_EQ(test, 42ul, t->id); + t = damon_new_target(); KUNIT_EXPECT_EQ(test, 0u, nr_damon_targets(c)); damon_add_target(c, t); @@ -78,7 +77,6 @@ static void damon_test_target(struct kunit *test) static void damon_test_aggregate(struct kunit *test) { struct damon_ctx *ctx = damon_new_ctx(); - unsigned long target_ids[] = {1, 2, 3}; unsigned long saddr[][3] = {{10, 20, 30}, {5, 42, 49}, {13, 33, 55} }; unsigned long eaddr[][3] = {{15, 27, 40}, {31, 45, 55}, {23, 44, 66} }; unsigned long accesses[][3] = {{42, 95, 84}, {10, 20, 30}, {0, 1, 2} }; @@ -87,7 +85,7 @@ static void damon_test_aggregate(struct kunit *test) int it, ir; for (it = 0; it < 3; it++) { - t = damon_new_target(target_ids[it]); + t = damon_new_target(); damon_add_target(ctx, t); } @@ -125,7 +123,7 @@ static void damon_test_split_at(struct kunit *test) struct damon_target *t; struct damon_region *r; - t = damon_new_target(42); + t = damon_new_target(); r = damon_new_region(0, 100); damon_add_region(r, t); damon_split_region_at(c, t, r, 25); @@ -146,7 +144,7 @@ static void damon_test_merge_two(struct kunit *test) struct damon_region *r, *r2, *r3; int i; - t = damon_new_target(42); + t = damon_new_target(); r = damon_new_region(0, 100); r->nr_accesses = 10; damon_add_region(r, t); @@ -194,7 +192,7 @@ static void damon_test_merge_regions_of(struct kunit *test) unsigned long eaddrs[] = {112, 130, 156, 170, 230}; int i; - t = damon_new_target(42); + t = damon_new_target(); for (i = 0; i < ARRAY_SIZE(sa); i++) { r = damon_new_region(sa[i], ea[i]); r->nr_accesses = nrs[i]; @@ -218,14 +216,14 @@ static void damon_test_split_regions_of(struct kunit *test) struct damon_target *t; struct damon_region *r; - t = damon_new_target(42); + t = damon_new_target(); r = damon_new_region(0, 22); damon_add_region(r, t); damon_split_regions_of(c, t, 2); KUNIT_EXPECT_LE(test, damon_nr_regions(t), 2u); damon_free_target(t); - t = damon_new_target(42); + t = damon_new_target(); r = damon_new_region(0, 220); damon_add_region(r, t); damon_split_regions_of(c, t, 4); diff --git a/mm/damon/core.c b/mm/damon/core.c index 3fef5c667a31..bf495236d741 100644 --- a/mm/damon/core.c +++ b/mm/damon/core.c @@ -144,7 +144,7 @@ void damon_destroy_scheme(struct damos *s) * * Returns the pointer to the new struct if success, or NULL otherwise */ -struct damon_target *damon_new_target(unsigned long id) +struct damon_target *damon_new_target(void) { struct damon_target *t; @@ -152,7 +152,7 @@ struct damon_target *damon_new_target(unsigned long id) if (!t) return NULL; - t->id = id; + t->pid = NULL; t->nr_regions = 0; INIT_LIST_HEAD(&t->regions_list); diff --git a/mm/damon/dbgfs-test.h b/mm/damon/dbgfs-test.h index c1c988b607bc..0d3a14c00acf 100644 --- a/mm/damon/dbgfs-test.h +++ b/mm/damon/dbgfs-test.h @@ -12,66 +12,58 @@ #include -static void damon_dbgfs_test_str_to_target_ids(struct kunit *test) +static void damon_dbgfs_test_str_to_ints(struct kunit *test) { char *question; - unsigned long *answers; - unsigned long expected[] = {12, 35, 46}; + int *answers; + int expected[] = {12, 35, 46}; ssize_t nr_integers = 0, i; question = "123"; - answers = str_to_target_ids(question, strlen(question), - &nr_integers); + answers = str_to_ints(question, strlen(question), &nr_integers); KUNIT_EXPECT_EQ(test, (ssize_t)1, nr_integers); - KUNIT_EXPECT_EQ(test, 123ul, answers[0]); + KUNIT_EXPECT_EQ(test, 123, answers[0]); kfree(answers); question = "123abc"; - answers = str_to_target_ids(question, strlen(question), - &nr_integers); + answers = str_to_ints(question, strlen(question), &nr_integers); KUNIT_EXPECT_EQ(test, (ssize_t)1, nr_integers); - KUNIT_EXPECT_EQ(test, 123ul, answers[0]); + KUNIT_EXPECT_EQ(test, 123, answers[0]); kfree(answers); question = "a123"; - answers = str_to_target_ids(question, strlen(question), - &nr_integers); + answers = str_to_ints(question, strlen(question), &nr_integers); KUNIT_EXPECT_EQ(test, (ssize_t)0, nr_integers); kfree(answers); question = "12 35"; - answers = str_to_target_ids(question, strlen(question), - &nr_integers); + answers = str_to_ints(question, strlen(question), &nr_integers); KUNIT_EXPECT_EQ(test, (ssize_t)2, nr_integers); for (i = 0; i < nr_integers; i++) KUNIT_EXPECT_EQ(test, expected[i], answers[i]); kfree(answers); question = "12 35 46"; - answers = str_to_target_ids(question, strlen(question), - &nr_integers); + answers = str_to_ints(question, strlen(question), &nr_integers); KUNIT_EXPECT_EQ(test, (ssize_t)3, nr_integers); for (i = 0; i < nr_integers; i++) KUNIT_EXPECT_EQ(test, expected[i], answers[i]); kfree(answers); question = "12 35 abc 46"; - answers = str_to_target_ids(question, strlen(question), - &nr_integers); + answers = str_to_ints(question, strlen(question), &nr_integers); KUNIT_EXPECT_EQ(test, (ssize_t)2, nr_integers); for (i = 0; i < 2; i++) KUNIT_EXPECT_EQ(test, expected[i], answers[i]); kfree(answers); question = ""; - answers = str_to_target_ids(question, strlen(question), - &nr_integers); + answers = str_to_ints(question, strlen(question), &nr_integers); KUNIT_EXPECT_EQ(test, (ssize_t)0, nr_integers); kfree(answers); question = "\n"; - answers = str_to_target_ids(question, strlen(question), - &nr_integers); + answers = str_to_ints(question, strlen(question), &nr_integers); KUNIT_EXPECT_EQ(test, (ssize_t)0, nr_integers); kfree(answers); } @@ -79,30 +71,20 @@ static void damon_dbgfs_test_str_to_target_ids(struct kunit *test) static void damon_dbgfs_test_set_targets(struct kunit *test) { struct damon_ctx *ctx = dbgfs_new_ctx(); - unsigned long ids[] = {1, 2, 3}; char buf[64]; - /* Make DAMON consider target id as plain number */ - ctx->primitive.target_valid = NULL; - ctx->primitive.cleanup = NULL; + /* Make DAMON consider target has no pid */ + ctx->primitive = (struct damon_primitive){}; - dbgfs_set_targets(ctx, ids, 3); - sprint_target_ids(ctx, buf, 64); - KUNIT_EXPECT_STREQ(test, (char *)buf, "1 2 3\n"); - - dbgfs_set_targets(ctx, NULL, 0); + dbgfs_set_targets(ctx, 0, NULL); sprint_target_ids(ctx, buf, 64); KUNIT_EXPECT_STREQ(test, (char *)buf, "\n"); - dbgfs_set_targets(ctx, (unsigned long []){1, 2}, 2); - sprint_target_ids(ctx, buf, 64); - KUNIT_EXPECT_STREQ(test, (char *)buf, "1 2\n"); - - dbgfs_set_targets(ctx, (unsigned long []){2}, 1); + dbgfs_set_targets(ctx, 1, NULL); sprint_target_ids(ctx, buf, 64); - KUNIT_EXPECT_STREQ(test, (char *)buf, "2\n"); + KUNIT_EXPECT_STREQ(test, (char *)buf, "42\n"); - dbgfs_set_targets(ctx, NULL, 0); + dbgfs_set_targets(ctx, 0, NULL); sprint_target_ids(ctx, buf, 64); KUNIT_EXPECT_STREQ(test, (char *)buf, "\n"); @@ -112,7 +94,6 @@ static void damon_dbgfs_test_set_targets(struct kunit *test) static void damon_dbgfs_test_set_init_regions(struct kunit *test) { struct damon_ctx *ctx = damon_new_ctx(); - unsigned long ids[] = {1, 2, 3}; /* Each line represents one region in `` `` */ char * const valid_inputs[] = {"1 10 20\n 1 20 30\n1 35 45", "1 10 20\n", @@ -130,7 +111,7 @@ static void damon_dbgfs_test_set_init_regions(struct kunit *test) int i, rc; char buf[256]; - dbgfs_set_targets(ctx, ids, 3); + dbgfs_set_targets(ctx, 3, NULL); /* Put valid inputs and check the results */ for (i = 0; i < ARRAY_SIZE(valid_inputs); i++) { @@ -158,12 +139,12 @@ static void damon_dbgfs_test_set_init_regions(struct kunit *test) KUNIT_EXPECT_STREQ(test, (char *)buf, ""); } - dbgfs_set_targets(ctx, NULL, 0); + dbgfs_set_targets(ctx, 0, NULL); damon_destroy_ctx(ctx); } static struct kunit_case damon_test_cases[] = { - KUNIT_CASE(damon_dbgfs_test_str_to_target_ids), + KUNIT_CASE(damon_dbgfs_test_str_to_ints), KUNIT_CASE(damon_dbgfs_test_set_targets), KUNIT_CASE(damon_dbgfs_test_set_init_regions), {}, diff --git a/mm/damon/dbgfs.c b/mm/damon/dbgfs.c index 58867b966635..78ff645433c6 100644 --- a/mm/damon/dbgfs.c +++ b/mm/damon/dbgfs.c @@ -275,7 +275,7 @@ out: return ret; } -static inline bool targetid_is_pid(const struct damon_ctx *ctx) +static inline bool target_has_pid(const struct damon_ctx *ctx) { return ctx->primitive.target_valid == damon_va_target_valid; } @@ -283,17 +283,19 @@ static inline bool targetid_is_pid(const struct damon_ctx *ctx) static ssize_t sprint_target_ids(struct damon_ctx *ctx, char *buf, ssize_t len) { struct damon_target *t; - unsigned long id; + int id; int written = 0; int rc; damon_for_each_target(t, ctx) { - id = t->id; - if (targetid_is_pid(ctx)) + if (target_has_pid(ctx)) /* Show pid numbers to debugfs users */ - id = (unsigned long)pid_vnr((struct pid *)id); + id = pid_vnr(t->pid); + else + /* Show 42 for physical address space, just for fun */ + id = 42; - rc = scnprintf(&buf[written], len - written, "%lu ", id); + rc = scnprintf(&buf[written], len - written, "%d ", id); if (!rc) return -ENOMEM; written += rc; @@ -321,75 +323,114 @@ static ssize_t dbgfs_target_ids_read(struct file *file, } /* - * Converts a string into an array of unsigned long integers + * Converts a string into an integers array * - * Returns an array of unsigned long integers if the conversion success, or - * NULL otherwise. + * Returns an array of integers array if the conversion success, or NULL + * otherwise. */ -static unsigned long *str_to_target_ids(const char *str, ssize_t len, - ssize_t *nr_ids) +static int *str_to_ints(const char *str, ssize_t len, ssize_t *nr_ints) { - unsigned long *ids; - const int max_nr_ids = 32; - unsigned long id; + int *array; + const int max_nr_ints = 32; + int nr; int pos = 0, parsed, ret; - *nr_ids = 0; - ids = kmalloc_array(max_nr_ids, sizeof(id), GFP_KERNEL); - if (!ids) + *nr_ints = 0; + array = kmalloc_array(max_nr_ints, sizeof(*array), GFP_KERNEL); + if (!array) return NULL; - while (*nr_ids < max_nr_ids && pos < len) { - ret = sscanf(&str[pos], "%lu%n", &id, &parsed); + while (*nr_ints < max_nr_ints && pos < len) { + ret = sscanf(&str[pos], "%d%n", &nr, &parsed); pos += parsed; if (ret != 1) break; - ids[*nr_ids] = id; - *nr_ids += 1; + array[*nr_ints] = nr; + *nr_ints += 1; } - return ids; + return array; } -static void dbgfs_put_pids(unsigned long *ids, int nr_ids) +static void dbgfs_put_pids(struct pid **pids, int nr_pids) { int i; - for (i = 0; i < nr_ids; i++) - put_pid((struct pid *)ids[i]); + for (i = 0; i < nr_pids; i++) + put_pid(pids[i]); +} + +/* + * Converts a string into an struct pid pointers array + * + * Returns an array of struct pid pointers if the conversion success, or NULL + * otherwise. + */ +static struct pid **str_to_pids(const char *str, ssize_t len, ssize_t *nr_pids) +{ + int *ints; + ssize_t nr_ints; + struct pid **pids; + + *nr_pids = 0; + + ints = str_to_ints(str, len, &nr_ints); + if (!ints) + return NULL; + + pids = kmalloc_array(nr_ints, sizeof(*pids), GFP_KERNEL); + if (!pids) + goto out; + + for (; *nr_pids < nr_ints; (*nr_pids)++) { + pids[*nr_pids] = find_get_pid(ints[*nr_pids]); + if (!pids[*nr_pids]) { + dbgfs_put_pids(pids, *nr_pids); + kfree(ints); + kfree(pids); + return NULL; + } + } + +out: + kfree(ints); + return pids; } /* * dbgfs_set_targets() - Set monitoring targets. * @ctx: monitoring context - * @ids: array of target ids - * @nr_ids: number of entries in @ids + * @nr_targets: number of targets + * @pids: array of target pids (size is same to @nr_targets) * - * This function should not be called while the kdamond is running. + * This function should not be called while the kdamond is running. @pids is + * ignored if the context is not configured to have pid in each target. On + * failure, reference counts of all pids in @pids are decremented. * * Return: 0 on success, negative error code otherwise. */ -static int dbgfs_set_targets(struct damon_ctx *ctx, - unsigned long *ids, ssize_t nr_ids) +static int dbgfs_set_targets(struct damon_ctx *ctx, ssize_t nr_targets, + struct pid **pids) { ssize_t i; struct damon_target *t, *next; damon_for_each_target_safe(t, next, ctx) { - if (targetid_is_pid(ctx)) - put_pid((struct pid *)t->id); + if (target_has_pid(ctx)) + put_pid(t->pid); damon_destroy_target(t); } - for (i = 0; i < nr_ids; i++) { - t = damon_new_target(ids[i]); + for (i = 0; i < nr_targets; i++) { + t = damon_new_target(); if (!t) { - /* The caller should do cleanup of the ids itself */ damon_for_each_target_safe(t, next, ctx) damon_destroy_target(t); - if (targetid_is_pid(ctx)) - dbgfs_put_pids(ids, nr_ids); + if (target_has_pid(ctx)) + dbgfs_put_pids(pids, nr_targets); return -ENOMEM; } + if (target_has_pid(ctx)) + t->pid = pids[i]; damon_add_target(ctx, t); } @@ -402,10 +443,9 @@ static ssize_t dbgfs_target_ids_write(struct file *file, struct damon_ctx *ctx = file->private_data; bool id_is_pid = true; char *kbuf; - unsigned long *targets; + struct pid **target_pids = NULL; ssize_t nr_targets; ssize_t ret; - int i; kbuf = user_input_str(buf, count, ppos); if (IS_ERR(kbuf)) @@ -413,38 +453,27 @@ static ssize_t dbgfs_target_ids_write(struct file *file, if (!strncmp(kbuf, "paddr\n", count)) { id_is_pid = false; - /* target id is meaningless here, but we set it just for fun */ - scnprintf(kbuf, count, "42 "); - } - - targets = str_to_target_ids(kbuf, count, &nr_targets); - if (!targets) { - ret = -ENOMEM; - goto out; + nr_targets = 1; } if (id_is_pid) { - for (i = 0; i < nr_targets; i++) { - targets[i] = (unsigned long)find_get_pid( - (int)targets[i]); - if (!targets[i]) { - dbgfs_put_pids(targets, i); - ret = -EINVAL; - goto free_targets_out; - } + target_pids = str_to_pids(kbuf, count, &nr_targets); + if (!target_pids) { + ret = -ENOMEM; + goto out; } } mutex_lock(&ctx->kdamond_lock); if (ctx->kdamond) { if (id_is_pid) - dbgfs_put_pids(targets, nr_targets); + dbgfs_put_pids(target_pids, nr_targets); ret = -EBUSY; goto unlock_out; } /* remove previously set targets */ - dbgfs_set_targets(ctx, NULL, 0); + dbgfs_set_targets(ctx, 0, NULL); /* Configure the context for the address space type */ if (id_is_pid) @@ -452,14 +481,13 @@ static ssize_t dbgfs_target_ids_write(struct file *file, else damon_pa_set_primitives(ctx); - ret = dbgfs_set_targets(ctx, targets, nr_targets); + ret = dbgfs_set_targets(ctx, nr_targets, target_pids); if (!ret) ret = count; unlock_out: mutex_unlock(&ctx->kdamond_lock); -free_targets_out: - kfree(targets); + kfree(target_pids); out: kfree(kbuf); return ret; @@ -688,12 +716,12 @@ static void dbgfs_before_terminate(struct damon_ctx *ctx) { struct damon_target *t, *next; - if (!targetid_is_pid(ctx)) + if (!target_has_pid(ctx)) return; mutex_lock(&ctx->kdamond_lock); damon_for_each_target_safe(t, next, ctx) { - put_pid((struct pid *)t->id); + put_pid(t->pid); damon_destroy_target(t); } mutex_unlock(&ctx->kdamond_lock); diff --git a/mm/damon/reclaim.c b/mm/damon/reclaim.c index bc476cef688e..29da37192e4a 100644 --- a/mm/damon/reclaim.c +++ b/mm/damon/reclaim.c @@ -387,8 +387,7 @@ static int __init damon_reclaim_init(void) damon_pa_set_primitives(ctx); ctx->callback.after_aggregation = damon_reclaim_after_aggregation; - /* 4242 means nothing but fun */ - target = damon_new_target(4242); + target = damon_new_target(); if (!target) { damon_destroy_ctx(ctx); return -ENOMEM; diff --git a/mm/damon/vaddr-test.h b/mm/damon/vaddr-test.h index 6a1b9272ea12..f0d0ba591792 100644 --- a/mm/damon/vaddr-test.h +++ b/mm/damon/vaddr-test.h @@ -139,7 +139,7 @@ static void damon_do_test_apply_three_regions(struct kunit *test, struct damon_region *r; int i; - t = damon_new_target(42); + t = damon_new_target(); for (i = 0; i < nr_regions / 2; i++) { r = damon_new_region(regions[i * 2], regions[i * 2 + 1]); damon_add_region(r, t); @@ -251,7 +251,7 @@ static void damon_test_apply_three_regions4(struct kunit *test) static void damon_test_split_evenly_fail(struct kunit *test, unsigned long start, unsigned long end, unsigned int nr_pieces) { - struct damon_target *t = damon_new_target(42); + struct damon_target *t = damon_new_target(); struct damon_region *r = damon_new_region(start, end); damon_add_region(r, t); @@ -270,7 +270,7 @@ static void damon_test_split_evenly_fail(struct kunit *test, static void damon_test_split_evenly_succ(struct kunit *test, unsigned long start, unsigned long end, unsigned int nr_pieces) { - struct damon_target *t = damon_new_target(42); + struct damon_target *t = damon_new_target(); struct damon_region *r = damon_new_region(start, end); unsigned long expected_width = (end - start) / nr_pieces; unsigned long i = 0; diff --git a/mm/damon/vaddr.c b/mm/damon/vaddr.c index 89b6468da2b9..f98edb90a873 100644 --- a/mm/damon/vaddr.c +++ b/mm/damon/vaddr.c @@ -23,12 +23,12 @@ #endif /* - * 't->id' should be the pointer to the relevant 'struct pid' having reference + * 't->pid' should be the pointer to the relevant 'struct pid' having reference * count. Caller must put the returned task, unless it is NULL. */ static inline struct task_struct *damon_get_task_struct(struct damon_target *t) { - return get_pid_task((struct pid *)t->id, PIDTYPE_PID); + return get_pid_task(t->pid, PIDTYPE_PID); } /* -- cgit v1.2.3 From f7d911c39cbbb88d625216a0cfd0517a3047c46e Mon Sep 17 00:00:00 2001 From: SeongJae Park Date: Tue, 22 Mar 2022 14:48:46 -0700 Subject: mm/damon: rename damon_primitives to damon_operations Patch series "Allow DAMON user code independent of monitoring primitives". In-kernel DAMON user code is required to configure the monitoring context (struct damon_ctx) with proper monitoring primitives (struct damon_primitive). This makes the user code dependent to all supporting monitoring primitives. For example, DAMON debugfs interface depends on both DAMON_VADDR and DAMON_PADDR, though some users have interest in only one use case. As more monitoring primitives are introduced, the problem will be bigger. To minimize such unnecessary dependency, this patchset makes monitoring primitives can be registered by the implemnting code and later dynamically searched and selected by the user code. In addition to that, this patchset renames monitoring primitives to monitoring operations, which is more easy to intuitively understand what it means and how it would be structed. This patch (of 8): DAMON has a set of callback functions called monitoring primitives and let it can be configured with various implementations for easy extension for different address spaces and usages. However, the word 'primitive' is not so explicit. Meanwhile, many other structs resembles similar purpose calls themselves 'operations'. To make the code easier to be understood, this commit renames 'damon_primitives' to 'damon_operations' before it is too late to rename. Link: https://lkml.kernel.org/r/20220215184603.1479-1-sj@kernel.org Link: https://lkml.kernel.org/r/20220215184603.1479-2-sj@kernel.org Signed-off-by: SeongJae Park Cc: Xin Hao Cc: David Rientjes Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/damon.h | 48 ++++++++--------- mm/damon/Kconfig | 12 ++--- mm/damon/Makefile | 4 +- mm/damon/core.c | 65 +++++++++++------------ mm/damon/dbgfs-test.h | 2 +- mm/damon/dbgfs.c | 10 ++-- mm/damon/ops-common.c | 133 ++++++++++++++++++++++++++++++++++++++++++++++++ mm/damon/ops-common.h | 16 ++++++ mm/damon/paddr.c | 22 ++++---- mm/damon/prmtv-common.c | 133 ------------------------------------------------ mm/damon/prmtv-common.h | 16 ------ mm/damon/reclaim.c | 2 +- mm/damon/vaddr-test.h | 2 +- mm/damon/vaddr.c | 22 ++++---- 14 files changed, 244 insertions(+), 243 deletions(-) create mode 100644 mm/damon/ops-common.c create mode 100644 mm/damon/ops-common.h delete mode 100644 mm/damon/prmtv-common.c delete mode 100644 mm/damon/prmtv-common.h (limited to 'include/linux') diff --git a/include/linux/damon.h b/include/linux/damon.h index 7c1d915b3587..00baeb42c18e 100644 --- a/include/linux/damon.h +++ b/include/linux/damon.h @@ -67,8 +67,8 @@ struct damon_region { * * Each monitoring context could have multiple targets. For example, a context * for virtual memory address spaces could have multiple target processes. The - * @pid should be set for appropriate address space monitoring primitives - * including the virtual address spaces monitoring primitives. + * @pid should be set for appropriate &struct damon_operations including the + * virtual address spaces monitoring operations. */ struct damon_target { struct pid *pid; @@ -120,9 +120,9 @@ enum damos_action { * uses smaller one as the effective quota. * * For selecting regions within the quota, DAMON prioritizes current scheme's - * target memory regions using the &struct damon_primitive->get_scheme_score. + * target memory regions using the &struct damon_operations->get_scheme_score. * You could customize the prioritization logic by setting &weight_sz, - * &weight_nr_accesses, and &weight_age, because monitoring primitives are + * &weight_nr_accesses, and &weight_age, because monitoring operations are * encouraged to respect those. */ struct damos_quota { @@ -256,10 +256,10 @@ struct damos { struct damon_ctx; /** - * struct damon_primitive - Monitoring primitives for given use cases. + * struct damon_operations - Monitoring operations for given use cases. * - * @init: Initialize primitive-internal data structures. - * @update: Update primitive-internal data structures. + * @init: Initialize operations-related data structures. + * @update: Update operations-related data structures. * @prepare_access_checks: Prepare next access check of target regions. * @check_accesses: Check the accesses to target regions. * @reset_aggregated: Reset aggregated accesses monitoring results. @@ -269,18 +269,18 @@ struct damon_ctx; * @cleanup: Clean up the context. * * DAMON can be extended for various address spaces and usages. For this, - * users should register the low level primitives for their target address - * space and usecase via the &damon_ctx.primitive. Then, the monitoring thread + * users should register the low level operations for their target address + * space and usecase via the &damon_ctx.ops. Then, the monitoring thread * (&damon_ctx.kdamond) calls @init and @prepare_access_checks before starting - * the monitoring, @update after each &damon_ctx.primitive_update_interval, and + * the monitoring, @update after each &damon_ctx.ops_update_interval, and * @check_accesses, @target_valid and @prepare_access_checks after each * &damon_ctx.sample_interval. Finally, @reset_aggregated is called after each * &damon_ctx.aggr_interval. * - * @init should initialize primitive-internal data structures. For example, + * @init should initialize operations-related data structures. For example, * this could be used to construct proper monitoring target regions and link * those to @damon_ctx.adaptive_targets. - * @update should update the primitive-internal data structures. For example, + * @update should update the operations-related data structures. For example, * this could be used to update monitoring target regions for current status. * @prepare_access_checks should manipulate the monitoring regions to be * prepared for the next access check. @@ -300,7 +300,7 @@ struct damon_ctx; * monitoring. * @cleanup is called from @kdamond just before its termination. */ -struct damon_primitive { +struct damon_operations { void (*init)(struct damon_ctx *context); void (*update)(struct damon_ctx *context); void (*prepare_access_checks)(struct damon_ctx *context); @@ -354,15 +354,15 @@ struct damon_callback { * * @sample_interval: The time between access samplings. * @aggr_interval: The time between monitor results aggregations. - * @primitive_update_interval: The time between monitoring primitive updates. + * @ops_update_interval: The time between monitoring operations updates. * * For each @sample_interval, DAMON checks whether each region is accessed or * not. It aggregates and keeps the access information (number of accesses to * each region) for @aggr_interval time. DAMON also checks whether the target * memory regions need update (e.g., by ``mmap()`` calls from the application, * in case of virtual memory monitoring) and applies the changes for each - * @primitive_update_interval. All time intervals are in micro-seconds. - * Please refer to &struct damon_primitive and &struct damon_callback for more + * @ops_update_interval. All time intervals are in micro-seconds. + * Please refer to &struct damon_operations and &struct damon_callback for more * detail. * * @kdamond: Kernel thread who does the monitoring. @@ -374,7 +374,7 @@ struct damon_callback { * * Once started, the monitoring thread runs until explicitly required to be * terminated or every monitoring target is invalid. The validity of the - * targets is checked via the &damon_primitive.target_valid of @primitive. The + * targets is checked via the &damon_operations.target_valid of @ops. The * termination can also be explicitly requested by writing non-zero to * @kdamond_stop. The thread sets @kdamond to NULL when it terminates. * Therefore, users can know whether the monitoring is ongoing or terminated by @@ -384,7 +384,7 @@ struct damon_callback { * Note that the monitoring thread protects only @kdamond and @kdamond_stop via * @kdamond_lock. Accesses to other fields must be protected by themselves. * - * @primitive: Set of monitoring primitives for given use cases. + * @ops: Set of monitoring operations for given use cases. * @callback: Set of callbacks for monitoring events notifications. * * @min_nr_regions: The minimum number of adaptive monitoring regions. @@ -395,17 +395,17 @@ struct damon_callback { struct damon_ctx { unsigned long sample_interval; unsigned long aggr_interval; - unsigned long primitive_update_interval; + unsigned long ops_update_interval; /* private: internal use only */ struct timespec64 last_aggregation; - struct timespec64 last_primitive_update; + struct timespec64 last_ops_update; /* public: */ struct task_struct *kdamond; struct mutex kdamond_lock; - struct damon_primitive primitive; + struct damon_operations ops; struct damon_callback callback; unsigned long min_nr_regions; @@ -484,7 +484,7 @@ unsigned int damon_nr_regions(struct damon_target *t); struct damon_ctx *damon_new_ctx(void); void damon_destroy_ctx(struct damon_ctx *ctx); int damon_set_attrs(struct damon_ctx *ctx, unsigned long sample_int, - unsigned long aggr_int, unsigned long primitive_upd_int, + unsigned long aggr_int, unsigned long ops_upd_int, unsigned long min_nr_reg, unsigned long max_nr_reg); int damon_set_schemes(struct damon_ctx *ctx, struct damos **schemes, ssize_t nr_schemes); @@ -497,12 +497,12 @@ int damon_stop(struct damon_ctx **ctxs, int nr_ctxs); #ifdef CONFIG_DAMON_VADDR bool damon_va_target_valid(void *t); -void damon_va_set_primitives(struct damon_ctx *ctx); +void damon_va_set_operations(struct damon_ctx *ctx); #endif /* CONFIG_DAMON_VADDR */ #ifdef CONFIG_DAMON_PADDR bool damon_pa_target_valid(void *t); -void damon_pa_set_primitives(struct damon_ctx *ctx); +void damon_pa_set_operations(struct damon_ctx *ctx); #endif /* CONFIG_DAMON_PADDR */ #endif /* _DAMON_H */ diff --git a/mm/damon/Kconfig b/mm/damon/Kconfig index 5bcf05851ad0..01bad77ad7ae 100644 --- a/mm/damon/Kconfig +++ b/mm/damon/Kconfig @@ -25,27 +25,27 @@ config DAMON_KUNIT_TEST If unsure, say N. config DAMON_VADDR - bool "Data access monitoring primitives for virtual address spaces" + bool "Data access monitoring operations for virtual address spaces" depends on DAMON && MMU select PAGE_IDLE_FLAG help - This builds the default data access monitoring primitives for DAMON + This builds the default data access monitoring operations for DAMON that work for virtual address spaces. config DAMON_PADDR - bool "Data access monitoring primitives for the physical address space" + bool "Data access monitoring operations for the physical address space" depends on DAMON && MMU select PAGE_IDLE_FLAG help - This builds the default data access monitoring primitives for DAMON + This builds the default data access monitoring operations for DAMON that works for the physical address space. config DAMON_VADDR_KUNIT_TEST - bool "Test for DAMON primitives" if !KUNIT_ALL_TESTS + bool "Test for DAMON operations" if !KUNIT_ALL_TESTS depends on DAMON_VADDR && KUNIT=y default KUNIT_ALL_TESTS help - This builds the DAMON virtual addresses primitives Kunit test suite. + This builds the DAMON virtual addresses operations Kunit test suite. For more information on KUnit and unit tests in general, please refer to the KUnit documentation. diff --git a/mm/damon/Makefile b/mm/damon/Makefile index f7d5ac377a2b..03931472991a 100644 --- a/mm/damon/Makefile +++ b/mm/damon/Makefile @@ -1,7 +1,7 @@ # SPDX-License-Identifier: GPL-2.0 obj-$(CONFIG_DAMON) := core.o -obj-$(CONFIG_DAMON_VADDR) += prmtv-common.o vaddr.o -obj-$(CONFIG_DAMON_PADDR) += prmtv-common.o paddr.o +obj-$(CONFIG_DAMON_VADDR) += ops-common.o vaddr.o +obj-$(CONFIG_DAMON_PADDR) += ops-common.o paddr.o obj-$(CONFIG_DAMON_DBGFS) += dbgfs.o obj-$(CONFIG_DAMON_RECLAIM) += reclaim.o diff --git a/mm/damon/core.c b/mm/damon/core.c index bf495236d741..be93fb1c3473 100644 --- a/mm/damon/core.c +++ b/mm/damon/core.c @@ -204,10 +204,10 @@ struct damon_ctx *damon_new_ctx(void) ctx->sample_interval = 5 * 1000; ctx->aggr_interval = 100 * 1000; - ctx->primitive_update_interval = 60 * 1000 * 1000; + ctx->ops_update_interval = 60 * 1000 * 1000; ktime_get_coarse_ts64(&ctx->last_aggregation); - ctx->last_primitive_update = ctx->last_aggregation; + ctx->last_ops_update = ctx->last_aggregation; mutex_init(&ctx->kdamond_lock); @@ -224,8 +224,8 @@ static void damon_destroy_targets(struct damon_ctx *ctx) { struct damon_target *t, *next_t; - if (ctx->primitive.cleanup) { - ctx->primitive.cleanup(ctx); + if (ctx->ops.cleanup) { + ctx->ops.cleanup(ctx); return; } @@ -250,7 +250,7 @@ void damon_destroy_ctx(struct damon_ctx *ctx) * @ctx: monitoring context * @sample_int: time interval between samplings * @aggr_int: time interval between aggregations - * @primitive_upd_int: time interval between monitoring primitive updates + * @ops_upd_int: time interval between monitoring operations updates * @min_nr_reg: minimal number of regions * @max_nr_reg: maximum number of regions * @@ -260,7 +260,7 @@ void damon_destroy_ctx(struct damon_ctx *ctx) * Return: 0 on success, negative error code otherwise. */ int damon_set_attrs(struct damon_ctx *ctx, unsigned long sample_int, - unsigned long aggr_int, unsigned long primitive_upd_int, + unsigned long aggr_int, unsigned long ops_upd_int, unsigned long min_nr_reg, unsigned long max_nr_reg) { if (min_nr_reg < 3) @@ -270,7 +270,7 @@ int damon_set_attrs(struct damon_ctx *ctx, unsigned long sample_int, ctx->sample_interval = sample_int; ctx->aggr_interval = aggr_int; - ctx->primitive_update_interval = primitive_upd_int; + ctx->ops_update_interval = ops_upd_int; ctx->min_nr_regions = min_nr_reg; ctx->max_nr_regions = max_nr_reg; @@ -516,10 +516,10 @@ static bool damos_valid_target(struct damon_ctx *c, struct damon_target *t, { bool ret = __damos_valid_target(r, s); - if (!ret || !s->quota.esz || !c->primitive.get_scheme_score) + if (!ret || !s->quota.esz || !c->ops.get_scheme_score) return ret; - return c->primitive.get_scheme_score(c, t, r, s) >= s->quota.min_score; + return c->ops.get_scheme_score(c, t, r, s) >= s->quota.min_score; } static void damon_do_apply_schemes(struct damon_ctx *c, @@ -576,7 +576,7 @@ static void damon_do_apply_schemes(struct damon_ctx *c, continue; /* Apply the scheme */ - if (c->primitive.apply_scheme) { + if (c->ops.apply_scheme) { if (quota->esz && quota->charged_sz + sz > quota->esz) { sz = ALIGN_DOWN(quota->esz - quota->charged_sz, @@ -586,7 +586,7 @@ static void damon_do_apply_schemes(struct damon_ctx *c, damon_split_region_at(c, t, r, sz); } ktime_get_coarse_ts64(&begin); - sz_applied = c->primitive.apply_scheme(c, t, r, s); + sz_applied = c->ops.apply_scheme(c, t, r, s); ktime_get_coarse_ts64(&end); quota->total_charged_ns += timespec64_to_ns(&end) - timespec64_to_ns(&begin); @@ -660,7 +660,7 @@ static void kdamond_apply_schemes(struct damon_ctx *c) damos_set_effective_quota(quota); } - if (!c->primitive.get_scheme_score) + if (!c->ops.get_scheme_score) continue; /* Fill up the score histogram */ @@ -669,7 +669,7 @@ static void kdamond_apply_schemes(struct damon_ctx *c) damon_for_each_region(r, t) { if (!__damos_valid_target(r, s)) continue; - score = c->primitive.get_scheme_score( + score = c->ops.get_scheme_score( c, t, r, s); quota->histogram[score] += r->ar.end - r->ar.start; @@ -848,14 +848,15 @@ static void kdamond_split_regions(struct damon_ctx *ctx) } /* - * Check whether it is time to check and apply the target monitoring regions + * Check whether it is time to check and apply the operations-related data + * structures. * * Returns true if it is. */ -static bool kdamond_need_update_primitive(struct damon_ctx *ctx) +static bool kdamond_need_update_operations(struct damon_ctx *ctx) { - return damon_check_reset_time_interval(&ctx->last_primitive_update, - ctx->primitive_update_interval); + return damon_check_reset_time_interval(&ctx->last_ops_update, + ctx->ops_update_interval); } /* @@ -873,11 +874,11 @@ static bool kdamond_need_stop(struct damon_ctx *ctx) if (kthread_should_stop()) return true; - if (!ctx->primitive.target_valid) + if (!ctx->ops.target_valid) return false; damon_for_each_target(t, ctx) { - if (ctx->primitive.target_valid(t)) + if (ctx->ops.target_valid(t)) return false; } @@ -976,8 +977,8 @@ static int kdamond_fn(void *data) pr_debug("kdamond (%d) starts\n", current->pid); - if (ctx->primitive.init) - ctx->primitive.init(ctx); + if (ctx->ops.init) + ctx->ops.init(ctx); if (ctx->callback.before_start && ctx->callback.before_start(ctx)) done = true; @@ -987,16 +988,16 @@ static int kdamond_fn(void *data) if (kdamond_wait_activation(ctx)) continue; - if (ctx->primitive.prepare_access_checks) - ctx->primitive.prepare_access_checks(ctx); + if (ctx->ops.prepare_access_checks) + ctx->ops.prepare_access_checks(ctx); if (ctx->callback.after_sampling && ctx->callback.after_sampling(ctx)) done = true; kdamond_usleep(ctx->sample_interval); - if (ctx->primitive.check_accesses) - max_nr_accesses = ctx->primitive.check_accesses(ctx); + if (ctx->ops.check_accesses) + max_nr_accesses = ctx->ops.check_accesses(ctx); if (kdamond_aggregate_interval_passed(ctx)) { kdamond_merge_regions(ctx, @@ -1008,13 +1009,13 @@ static int kdamond_fn(void *data) kdamond_apply_schemes(ctx); kdamond_reset_aggregated(ctx); kdamond_split_regions(ctx); - if (ctx->primitive.reset_aggregated) - ctx->primitive.reset_aggregated(ctx); + if (ctx->ops.reset_aggregated) + ctx->ops.reset_aggregated(ctx); } - if (kdamond_need_update_primitive(ctx)) { - if (ctx->primitive.update) - ctx->primitive.update(ctx); + if (kdamond_need_update_operations(ctx)) { + if (ctx->ops.update) + ctx->ops.update(ctx); sz_limit = damon_region_sz_limit(ctx); } } @@ -1025,8 +1026,8 @@ static int kdamond_fn(void *data) if (ctx->callback.before_terminate) ctx->callback.before_terminate(ctx); - if (ctx->primitive.cleanup) - ctx->primitive.cleanup(ctx); + if (ctx->ops.cleanup) + ctx->ops.cleanup(ctx); pr_debug("kdamond (%d) finishes\n", current->pid); mutex_lock(&ctx->kdamond_lock); diff --git a/mm/damon/dbgfs-test.h b/mm/damon/dbgfs-test.h index 0d3a14c00acf..8f7f32595055 100644 --- a/mm/damon/dbgfs-test.h +++ b/mm/damon/dbgfs-test.h @@ -74,7 +74,7 @@ static void damon_dbgfs_test_set_targets(struct kunit *test) char buf[64]; /* Make DAMON consider target has no pid */ - ctx->primitive = (struct damon_primitive){}; + ctx->ops = (struct damon_operations){}; dbgfs_set_targets(ctx, 0, NULL); sprint_target_ids(ctx, buf, 64); diff --git a/mm/damon/dbgfs.c b/mm/damon/dbgfs.c index 78ff645433c6..719278a8cc5e 100644 --- a/mm/damon/dbgfs.c +++ b/mm/damon/dbgfs.c @@ -56,7 +56,7 @@ static ssize_t dbgfs_attrs_read(struct file *file, mutex_lock(&ctx->kdamond_lock); ret = scnprintf(kbuf, ARRAY_SIZE(kbuf), "%lu %lu %lu %lu %lu\n", ctx->sample_interval, ctx->aggr_interval, - ctx->primitive_update_interval, ctx->min_nr_regions, + ctx->ops_update_interval, ctx->min_nr_regions, ctx->max_nr_regions); mutex_unlock(&ctx->kdamond_lock); @@ -277,7 +277,7 @@ out: static inline bool target_has_pid(const struct damon_ctx *ctx) { - return ctx->primitive.target_valid == damon_va_target_valid; + return ctx->ops.target_valid == damon_va_target_valid; } static ssize_t sprint_target_ids(struct damon_ctx *ctx, char *buf, ssize_t len) @@ -477,9 +477,9 @@ static ssize_t dbgfs_target_ids_write(struct file *file, /* Configure the context for the address space type */ if (id_is_pid) - damon_va_set_primitives(ctx); + damon_va_set_operations(ctx); else - damon_pa_set_primitives(ctx); + damon_pa_set_operations(ctx); ret = dbgfs_set_targets(ctx, nr_targets, target_pids); if (!ret) @@ -735,7 +735,7 @@ static struct damon_ctx *dbgfs_new_ctx(void) if (!ctx) return NULL; - damon_va_set_primitives(ctx); + damon_va_set_operations(ctx); ctx->callback.before_terminate = dbgfs_before_terminate; return ctx; } diff --git a/mm/damon/ops-common.c b/mm/damon/ops-common.c new file mode 100644 index 000000000000..e346cc10d143 --- /dev/null +++ b/mm/damon/ops-common.c @@ -0,0 +1,133 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Common Primitives for Data Access Monitoring + * + * Author: SeongJae Park + */ + +#include +#include +#include +#include + +#include "ops-common.h" + +/* + * Get an online page for a pfn if it's in the LRU list. Otherwise, returns + * NULL. + * + * The body of this function is stolen from the 'page_idle_get_page()'. We + * steal rather than reuse it because the code is quite simple. + */ +struct page *damon_get_page(unsigned long pfn) +{ + struct page *page = pfn_to_online_page(pfn); + + if (!page || !PageLRU(page) || !get_page_unless_zero(page)) + return NULL; + + if (unlikely(!PageLRU(page))) { + put_page(page); + page = NULL; + } + return page; +} + +void damon_ptep_mkold(pte_t *pte, struct mm_struct *mm, unsigned long addr) +{ + bool referenced = false; + struct page *page = damon_get_page(pte_pfn(*pte)); + + if (!page) + return; + + if (pte_young(*pte)) { + referenced = true; + *pte = pte_mkold(*pte); + } + +#ifdef CONFIG_MMU_NOTIFIER + if (mmu_notifier_clear_young(mm, addr, addr + PAGE_SIZE)) + referenced = true; +#endif /* CONFIG_MMU_NOTIFIER */ + + if (referenced) + set_page_young(page); + + set_page_idle(page); + put_page(page); +} + +void damon_pmdp_mkold(pmd_t *pmd, struct mm_struct *mm, unsigned long addr) +{ +#ifdef CONFIG_TRANSPARENT_HUGEPAGE + bool referenced = false; + struct page *page = damon_get_page(pmd_pfn(*pmd)); + + if (!page) + return; + + if (pmd_young(*pmd)) { + referenced = true; + *pmd = pmd_mkold(*pmd); + } + +#ifdef CONFIG_MMU_NOTIFIER + if (mmu_notifier_clear_young(mm, addr, + addr + ((1UL) << HPAGE_PMD_SHIFT))) + referenced = true; +#endif /* CONFIG_MMU_NOTIFIER */ + + if (referenced) + set_page_young(page); + + set_page_idle(page); + put_page(page); +#endif /* CONFIG_TRANSPARENT_HUGEPAGE */ +} + +#define DAMON_MAX_SUBSCORE (100) +#define DAMON_MAX_AGE_IN_LOG (32) + +int damon_pageout_score(struct damon_ctx *c, struct damon_region *r, + struct damos *s) +{ + unsigned int max_nr_accesses; + int freq_subscore; + unsigned int age_in_sec; + int age_in_log, age_subscore; + unsigned int freq_weight = s->quota.weight_nr_accesses; + unsigned int age_weight = s->quota.weight_age; + int hotness; + + max_nr_accesses = c->aggr_interval / c->sample_interval; + freq_subscore = r->nr_accesses * DAMON_MAX_SUBSCORE / max_nr_accesses; + + age_in_sec = (unsigned long)r->age * c->aggr_interval / 1000000; + for (age_in_log = 0; age_in_log < DAMON_MAX_AGE_IN_LOG && age_in_sec; + age_in_log++, age_in_sec >>= 1) + ; + + /* If frequency is 0, higher age means it's colder */ + if (freq_subscore == 0) + age_in_log *= -1; + + /* + * Now age_in_log is in [-DAMON_MAX_AGE_IN_LOG, DAMON_MAX_AGE_IN_LOG]. + * Scale it to be in [0, 100] and set it as age subscore. + */ + age_in_log += DAMON_MAX_AGE_IN_LOG; + age_subscore = age_in_log * DAMON_MAX_SUBSCORE / + DAMON_MAX_AGE_IN_LOG / 2; + + hotness = (freq_weight * freq_subscore + age_weight * age_subscore); + if (freq_weight + age_weight) + hotness /= freq_weight + age_weight; + /* + * Transform it to fit in [0, DAMOS_MAX_SCORE] + */ + hotness = hotness * DAMOS_MAX_SCORE / DAMON_MAX_SUBSCORE; + + /* Return coldness of the region */ + return DAMOS_MAX_SCORE - hotness; +} diff --git a/mm/damon/ops-common.h b/mm/damon/ops-common.h new file mode 100644 index 000000000000..e790cb5f8fe0 --- /dev/null +++ b/mm/damon/ops-common.h @@ -0,0 +1,16 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Common Primitives for Data Access Monitoring + * + * Author: SeongJae Park + */ + +#include + +struct page *damon_get_page(unsigned long pfn); + +void damon_ptep_mkold(pte_t *pte, struct mm_struct *mm, unsigned long addr); +void damon_pmdp_mkold(pmd_t *pmd, struct mm_struct *mm, unsigned long addr); + +int damon_pageout_score(struct damon_ctx *c, struct damon_region *r, + struct damos *s); diff --git a/mm/damon/paddr.c b/mm/damon/paddr.c index 5e8244f65a1a..9f0abd0369bc 100644 --- a/mm/damon/paddr.c +++ b/mm/damon/paddr.c @@ -14,7 +14,7 @@ #include #include "../internal.h" -#include "prmtv-common.h" +#include "ops-common.h" static bool __damon_pa_mkold(struct page *page, struct vm_area_struct *vma, unsigned long addr, void *arg) @@ -261,15 +261,15 @@ static int damon_pa_scheme_score(struct damon_ctx *context, return DAMOS_MAX_SCORE; } -void damon_pa_set_primitives(struct damon_ctx *ctx) +void damon_pa_set_operations(struct damon_ctx *ctx) { - ctx->primitive.init = NULL; - ctx->primitive.update = NULL; - ctx->primitive.prepare_access_checks = damon_pa_prepare_access_checks; - ctx->primitive.check_accesses = damon_pa_check_accesses; - ctx->primitive.reset_aggregated = NULL; - ctx->primitive.target_valid = damon_pa_target_valid; - ctx->primitive.cleanup = NULL; - ctx->primitive.apply_scheme = damon_pa_apply_scheme; - ctx->primitive.get_scheme_score = damon_pa_scheme_score; + ctx->ops.init = NULL; + ctx->ops.update = NULL; + ctx->ops.prepare_access_checks = damon_pa_prepare_access_checks; + ctx->ops.check_accesses = damon_pa_check_accesses; + ctx->ops.reset_aggregated = NULL; + ctx->ops.target_valid = damon_pa_target_valid; + ctx->ops.cleanup = NULL; + ctx->ops.apply_scheme = damon_pa_apply_scheme; + ctx->ops.get_scheme_score = damon_pa_scheme_score; } diff --git a/mm/damon/prmtv-common.c b/mm/damon/prmtv-common.c deleted file mode 100644 index 92a04f5831d6..000000000000 --- a/mm/damon/prmtv-common.c +++ /dev/null @@ -1,133 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0 -/* - * Common Primitives for Data Access Monitoring - * - * Author: SeongJae Park - */ - -#include -#include -#include -#include - -#include "prmtv-common.h" - -/* - * Get an online page for a pfn if it's in the LRU list. Otherwise, returns - * NULL. - * - * The body of this function is stolen from the 'page_idle_get_page()'. We - * steal rather than reuse it because the code is quite simple. - */ -struct page *damon_get_page(unsigned long pfn) -{ - struct page *page = pfn_to_online_page(pfn); - - if (!page || !PageLRU(page) || !get_page_unless_zero(page)) - return NULL; - - if (unlikely(!PageLRU(page))) { - put_page(page); - page = NULL; - } - return page; -} - -void damon_ptep_mkold(pte_t *pte, struct mm_struct *mm, unsigned long addr) -{ - bool referenced = false; - struct page *page = damon_get_page(pte_pfn(*pte)); - - if (!page) - return; - - if (pte_young(*pte)) { - referenced = true; - *pte = pte_mkold(*pte); - } - -#ifdef CONFIG_MMU_NOTIFIER - if (mmu_notifier_clear_young(mm, addr, addr + PAGE_SIZE)) - referenced = true; -#endif /* CONFIG_MMU_NOTIFIER */ - - if (referenced) - set_page_young(page); - - set_page_idle(page); - put_page(page); -} - -void damon_pmdp_mkold(pmd_t *pmd, struct mm_struct *mm, unsigned long addr) -{ -#ifdef CONFIG_TRANSPARENT_HUGEPAGE - bool referenced = false; - struct page *page = damon_get_page(pmd_pfn(*pmd)); - - if (!page) - return; - - if (pmd_young(*pmd)) { - referenced = true; - *pmd = pmd_mkold(*pmd); - } - -#ifdef CONFIG_MMU_NOTIFIER - if (mmu_notifier_clear_young(mm, addr, - addr + ((1UL) << HPAGE_PMD_SHIFT))) - referenced = true; -#endif /* CONFIG_MMU_NOTIFIER */ - - if (referenced) - set_page_young(page); - - set_page_idle(page); - put_page(page); -#endif /* CONFIG_TRANSPARENT_HUGEPAGE */ -} - -#define DAMON_MAX_SUBSCORE (100) -#define DAMON_MAX_AGE_IN_LOG (32) - -int damon_pageout_score(struct damon_ctx *c, struct damon_region *r, - struct damos *s) -{ - unsigned int max_nr_accesses; - int freq_subscore; - unsigned int age_in_sec; - int age_in_log, age_subscore; - unsigned int freq_weight = s->quota.weight_nr_accesses; - unsigned int age_weight = s->quota.weight_age; - int hotness; - - max_nr_accesses = c->aggr_interval / c->sample_interval; - freq_subscore = r->nr_accesses * DAMON_MAX_SUBSCORE / max_nr_accesses; - - age_in_sec = (unsigned long)r->age * c->aggr_interval / 1000000; - for (age_in_log = 0; age_in_log < DAMON_MAX_AGE_IN_LOG && age_in_sec; - age_in_log++, age_in_sec >>= 1) - ; - - /* If frequency is 0, higher age means it's colder */ - if (freq_subscore == 0) - age_in_log *= -1; - - /* - * Now age_in_log is in [-DAMON_MAX_AGE_IN_LOG, DAMON_MAX_AGE_IN_LOG]. - * Scale it to be in [0, 100] and set it as age subscore. - */ - age_in_log += DAMON_MAX_AGE_IN_LOG; - age_subscore = age_in_log * DAMON_MAX_SUBSCORE / - DAMON_MAX_AGE_IN_LOG / 2; - - hotness = (freq_weight * freq_subscore + age_weight * age_subscore); - if (freq_weight + age_weight) - hotness /= freq_weight + age_weight; - /* - * Transform it to fit in [0, DAMOS_MAX_SCORE] - */ - hotness = hotness * DAMOS_MAX_SCORE / DAMON_MAX_SUBSCORE; - - /* Return coldness of the region */ - return DAMOS_MAX_SCORE - hotness; -} diff --git a/mm/damon/prmtv-common.h b/mm/damon/prmtv-common.h deleted file mode 100644 index e790cb5f8fe0..000000000000 --- a/mm/damon/prmtv-common.h +++ /dev/null @@ -1,16 +0,0 @@ -/* SPDX-License-Identifier: GPL-2.0 */ -/* - * Common Primitives for Data Access Monitoring - * - * Author: SeongJae Park - */ - -#include - -struct page *damon_get_page(unsigned long pfn); - -void damon_ptep_mkold(pte_t *pte, struct mm_struct *mm, unsigned long addr); -void damon_pmdp_mkold(pmd_t *pmd, struct mm_struct *mm, unsigned long addr); - -int damon_pageout_score(struct damon_ctx *c, struct damon_region *r, - struct damos *s); diff --git a/mm/damon/reclaim.c b/mm/damon/reclaim.c index 29da37192e4a..3c93095c793c 100644 --- a/mm/damon/reclaim.c +++ b/mm/damon/reclaim.c @@ -384,7 +384,7 @@ static int __init damon_reclaim_init(void) if (!ctx) return -ENOMEM; - damon_pa_set_primitives(ctx); + damon_pa_set_operations(ctx); ctx->callback.after_aggregation = damon_reclaim_after_aggregation; target = damon_new_target(); diff --git a/mm/damon/vaddr-test.h b/mm/damon/vaddr-test.h index f0d0ba591792..1a55bb6c36c3 100644 --- a/mm/damon/vaddr-test.h +++ b/mm/damon/vaddr-test.h @@ -314,7 +314,7 @@ static struct kunit_case damon_test_cases[] = { }; static struct kunit_suite damon_test_suite = { - .name = "damon-primitives", + .name = "damon-operations", .test_cases = damon_test_cases, }; kunit_test_suite(damon_test_suite); diff --git a/mm/damon/vaddr.c b/mm/damon/vaddr.c index 6d3454dd3204..c0eb32025f9b 100644 --- a/mm/damon/vaddr.c +++ b/mm/damon/vaddr.c @@ -15,7 +15,7 @@ #include #include -#include "prmtv-common.h" +#include "ops-common.h" #ifdef CONFIG_DAMON_VADDR_KUNIT_TEST #undef DAMON_MIN_REGION @@ -739,17 +739,17 @@ static int damon_va_scheme_score(struct damon_ctx *context, return DAMOS_MAX_SCORE; } -void damon_va_set_primitives(struct damon_ctx *ctx) +void damon_va_set_operations(struct damon_ctx *ctx) { - ctx->primitive.init = damon_va_init; - ctx->primitive.update = damon_va_update; - ctx->primitive.prepare_access_checks = damon_va_prepare_access_checks; - ctx->primitive.check_accesses = damon_va_check_accesses; - ctx->primitive.reset_aggregated = NULL; - ctx->primitive.target_valid = damon_va_target_valid; - ctx->primitive.cleanup = NULL; - ctx->primitive.apply_scheme = damon_va_apply_scheme; - ctx->primitive.get_scheme_score = damon_va_scheme_score; + ctx->ops.init = damon_va_init; + ctx->ops.update = damon_va_update; + ctx->ops.prepare_access_checks = damon_va_prepare_access_checks; + ctx->ops.check_accesses = damon_va_check_accesses; + ctx->ops.reset_aggregated = NULL; + ctx->ops.target_valid = damon_va_target_valid; + ctx->ops.cleanup = NULL; + ctx->ops.apply_scheme = damon_va_apply_scheme; + ctx->ops.get_scheme_score = damon_va_scheme_score; } #include "vaddr-test.h" -- cgit v1.2.3 From 9f7b053a0f6121f89e00d1688bfca0bf278caa25 Mon Sep 17 00:00:00 2001 From: SeongJae Park Date: Tue, 22 Mar 2022 14:48:49 -0700 Subject: mm/damon: let monitoring operations can be registered and selected In-kernel DAMON user code like DAMON debugfs interface should set 'struct damon_operations' of its 'struct damon_ctx' on its own. Therefore, the client code should depend on all supporting monitoring operations implementations that it could use. For example, DAMON debugfs interface depends on both vaddr and paddr, while some of the users are not always interested in both. To minimize such unnecessary dependencies, this commit makes the monitoring operations can be registered by implementing code and then dynamically selected by the user code without build-time dependency. Link: https://lkml.kernel.org/r/20220215184603.1479-3-sj@kernel.org Signed-off-by: SeongJae Park Cc: David Rientjes Cc: Xin Hao Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/damon.h | 18 ++++++++++++++ mm/damon/core.c | 66 +++++++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 84 insertions(+) (limited to 'include/linux') diff --git a/include/linux/damon.h b/include/linux/damon.h index 00baeb42c18e..076da277b249 100644 --- a/include/linux/damon.h +++ b/include/linux/damon.h @@ -253,11 +253,24 @@ struct damos { struct list_head list; }; +/** + * enum damon_ops_id - Identifier for each monitoring operations implementation + * + * @DAMON_OPS_VADDR: Monitoring operations for virtual address spaces + * @DAMON_OPS_PADDR: Monitoring operations for the physical address space + */ +enum damon_ops_id { + DAMON_OPS_VADDR, + DAMON_OPS_PADDR, + NR_DAMON_OPS, +}; + struct damon_ctx; /** * struct damon_operations - Monitoring operations for given use cases. * + * @id: Identifier of this operations set. * @init: Initialize operations-related data structures. * @update: Update operations-related data structures. * @prepare_access_checks: Prepare next access check of target regions. @@ -277,6 +290,8 @@ struct damon_ctx; * &damon_ctx.sample_interval. Finally, @reset_aggregated is called after each * &damon_ctx.aggr_interval. * + * Each &struct damon_operations instance having valid @id can be registered + * via damon_register_ops() and selected by damon_select_ops() later. * @init should initialize operations-related data structures. For example, * this could be used to construct proper monitoring target regions and link * those to @damon_ctx.adaptive_targets. @@ -301,6 +316,7 @@ struct damon_ctx; * @cleanup is called from @kdamond just before its termination. */ struct damon_operations { + enum damon_ops_id id; void (*init)(struct damon_ctx *context); void (*update)(struct damon_ctx *context); void (*prepare_access_checks)(struct damon_ctx *context); @@ -489,6 +505,8 @@ int damon_set_attrs(struct damon_ctx *ctx, unsigned long sample_int, int damon_set_schemes(struct damon_ctx *ctx, struct damos **schemes, ssize_t nr_schemes); int damon_nr_running_ctxs(void); +int damon_register_ops(struct damon_operations *ops); +int damon_select_ops(struct damon_ctx *ctx, enum damon_ops_id id); int damon_start(struct damon_ctx **ctxs, int nr_ctxs); int damon_stop(struct damon_ctx **ctxs, int nr_ctxs); diff --git a/mm/damon/core.c b/mm/damon/core.c index be93fb1c3473..82e0a4620c4f 100644 --- a/mm/damon/core.c +++ b/mm/damon/core.c @@ -25,6 +25,72 @@ static DEFINE_MUTEX(damon_lock); static int nr_running_ctxs; +static DEFINE_MUTEX(damon_ops_lock); +static struct damon_operations damon_registered_ops[NR_DAMON_OPS]; + +/* Should be called under damon_ops_lock with id smaller than NR_DAMON_OPS */ +static bool damon_registered_ops_id(enum damon_ops_id id) +{ + struct damon_operations empty_ops = {}; + + if (!memcmp(&empty_ops, &damon_registered_ops[id], sizeof(empty_ops))) + return false; + return true; +} + +/** + * damon_register_ops() - Register a monitoring operations set to DAMON. + * @ops: monitoring operations set to register. + * + * This function registers a monitoring operations set of valid &struct + * damon_operations->id so that others can find and use them later. + * + * Return: 0 on success, negative error code otherwise. + */ +int damon_register_ops(struct damon_operations *ops) +{ + int err = 0; + + if (ops->id >= NR_DAMON_OPS) + return -EINVAL; + mutex_lock(&damon_ops_lock); + /* Fail for already registered ops */ + if (damon_registered_ops_id(ops->id)) { + err = -EINVAL; + goto out; + } + damon_registered_ops[ops->id] = *ops; +out: + mutex_unlock(&damon_ops_lock); + return err; +} + +/** + * damon_select_ops() - Select a monitoring operations to use with the context. + * @ctx: monitoring context to use the operations. + * @id: id of the registered monitoring operations to select. + * + * This function finds registered monitoring operations set of @id and make + * @ctx to use it. + * + * Return: 0 on success, negative error code otherwise. + */ +int damon_select_ops(struct damon_ctx *ctx, enum damon_ops_id id) +{ + int err = 0; + + if (id >= NR_DAMON_OPS) + return -EINVAL; + + mutex_lock(&damon_ops_lock); + if (!damon_registered_ops_id(id)) + err = -EINVAL; + else + ctx->ops = damon_registered_ops[id]; + mutex_unlock(&damon_ops_lock); + return err; +} + /* * Construct a damon_region struct * -- cgit v1.2.3 From 851040566a008f7248cb754d5bb9a3e34f2effe5 Mon Sep 17 00:00:00 2001 From: SeongJae Park Date: Tue, 22 Mar 2022 14:49:07 -0700 Subject: mm/damon/paddr,vaddr: remove damon_{p,v}a_{target_valid,set_operations}() Because DAMON debugfs interface and DAMON-based proactive reclaim are now using monitoring operations via registration mechanism, damon_{p,v}a_{target_valid,set_operations}() functions have no user. This commit clean them up. Link: https://lkml.kernel.org/r/20220215184603.1479-9-sj@kernel.org Signed-off-by: SeongJae Park Cc: David Rientjes Cc: Xin Hao Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/damon.h | 10 ---------- mm/damon/paddr.c | 20 +------------------- mm/damon/vaddr.c | 15 +-------------- 3 files changed, 2 insertions(+), 43 deletions(-) (limited to 'include/linux') diff --git a/include/linux/damon.h b/include/linux/damon.h index 076da277b249..49c4a11ecf20 100644 --- a/include/linux/damon.h +++ b/include/linux/damon.h @@ -513,14 +513,4 @@ int damon_stop(struct damon_ctx **ctxs, int nr_ctxs); #endif /* CONFIG_DAMON */ -#ifdef CONFIG_DAMON_VADDR -bool damon_va_target_valid(void *t); -void damon_va_set_operations(struct damon_ctx *ctx); -#endif /* CONFIG_DAMON_VADDR */ - -#ifdef CONFIG_DAMON_PADDR -bool damon_pa_target_valid(void *t); -void damon_pa_set_operations(struct damon_ctx *ctx); -#endif /* CONFIG_DAMON_PADDR */ - #endif /* _DAMON_H */ diff --git a/mm/damon/paddr.c b/mm/damon/paddr.c index d968bb38bd5d..7c263797a9a9 100644 --- a/mm/damon/paddr.c +++ b/mm/damon/paddr.c @@ -208,11 +208,6 @@ static unsigned int damon_pa_check_accesses(struct damon_ctx *ctx) return max_nr_accesses; } -bool damon_pa_target_valid(void *t) -{ - return true; -} - static unsigned long damon_pa_apply_scheme(struct damon_ctx *ctx, struct damon_target *t, struct damon_region *r, struct damos *scheme) @@ -261,19 +256,6 @@ static int damon_pa_scheme_score(struct damon_ctx *context, return DAMOS_MAX_SCORE; } -void damon_pa_set_operations(struct damon_ctx *ctx) -{ - ctx->ops.init = NULL; - ctx->ops.update = NULL; - ctx->ops.prepare_access_checks = damon_pa_prepare_access_checks; - ctx->ops.check_accesses = damon_pa_check_accesses; - ctx->ops.reset_aggregated = NULL; - ctx->ops.target_valid = damon_pa_target_valid; - ctx->ops.cleanup = NULL; - ctx->ops.apply_scheme = damon_pa_apply_scheme; - ctx->ops.get_scheme_score = damon_pa_scheme_score; -} - static int __init damon_pa_initcall(void) { struct damon_operations ops = { @@ -283,7 +265,7 @@ static int __init damon_pa_initcall(void) .prepare_access_checks = damon_pa_prepare_access_checks, .check_accesses = damon_pa_check_accesses, .reset_aggregated = NULL, - .target_valid = damon_pa_target_valid, + .target_valid = NULL, .cleanup = NULL, .apply_scheme = damon_pa_apply_scheme, .get_scheme_score = damon_pa_scheme_score, diff --git a/mm/damon/vaddr.c b/mm/damon/vaddr.c index 87475ba37bec..b2ec0aa1ff45 100644 --- a/mm/damon/vaddr.c +++ b/mm/damon/vaddr.c @@ -653,7 +653,7 @@ static unsigned int damon_va_check_accesses(struct damon_ctx *ctx) * Functions for the target validity check and cleanup */ -bool damon_va_target_valid(void *target) +static bool damon_va_target_valid(void *target) { struct damon_target *t = target; struct task_struct *task; @@ -739,19 +739,6 @@ static int damon_va_scheme_score(struct damon_ctx *context, return DAMOS_MAX_SCORE; } -void damon_va_set_operations(struct damon_ctx *ctx) -{ - ctx->ops.init = damon_va_init; - ctx->ops.update = damon_va_update; - ctx->ops.prepare_access_checks = damon_va_prepare_access_checks; - ctx->ops.check_accesses = damon_va_check_accesses; - ctx->ops.reset_aggregated = NULL; - ctx->ops.target_valid = damon_va_target_valid; - ctx->ops.cleanup = NULL; - ctx->ops.apply_scheme = damon_va_apply_scheme; - ctx->ops.get_scheme_score = damon_va_scheme_score; -} - static int __init damon_va_initcall(void) { struct damon_operations ops = { -- cgit v1.2.3 From 8b9b0d335a345cbc590baa5aa8aa02c467c1e4e8 Mon Sep 17 00:00:00 2001 From: SeongJae Park Date: Tue, 22 Mar 2022 14:49:21 -0700 Subject: mm/damon/core: allow non-exclusive DAMON start/stop MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Patch series "Introduce DAMON sysfs interface", v3. Introduction ============ DAMON's debugfs-based user interface (DAMON_DBGFS) served very well, so far. However, it unnecessarily depends on debugfs, while DAMON is not aimed to be used for only debugging. Also, the interface receives multiple values via one file. For example, schemes file receives 18 values. As a result, it is inefficient, hard to be used, and difficult to be extended. Especially, keeping backward compatibility of user space tools is getting only challenging. It would be better to implement another reliable and flexible interface and deprecate DAMON_DBGFS in long term. For the reason, this patchset introduces a sysfs-based new user interface of DAMON. The idea of the new interface is, using directory hierarchies and having one dedicated file for each value. For a short example, users can do the virtual address monitoring via the interface as below: # cd /sys/kernel/mm/damon/admin/ # echo 1 > kdamonds/nr_kdamonds # echo 1 > kdamonds/0/contexts/nr_contexts # echo vaddr > kdamonds/0/contexts/0/operations # echo 1 > kdamonds/0/contexts/0/targets/nr_targets # echo $(pidof ) > kdamonds/0/contexts/0/targets/0/pid_target # echo on > kdamonds/0/state A brief representation of the files hierarchy of DAMON sysfs interface is as below. Childs are represented with indentation, directories are having '/' suffix, and files in each directory are separated by comma. /sys/kernel/mm/damon/admin │ kdamonds/nr_kdamonds │ │ 0/state,pid │ │ │ contexts/nr_contexts │ │ │ │ 0/operations │ │ │ │ │ monitoring_attrs/ │ │ │ │ │ │ intervals/sample_us,aggr_us,update_us │ │ │ │ │ │ nr_regions/min,max │ │ │ │ │ targets/nr_targets │ │ │ │ │ │ 0/pid_target │ │ │ │ │ │ │ regions/nr_regions │ │ │ │ │ │ │ │ 0/start,end │ │ │ │ │ │ │ │ ... │ │ │ │ │ │ ... │ │ │ │ │ schemes/nr_schemes │ │ │ │ │ │ 0/action │ │ │ │ │ │ │ access_pattern/ │ │ │ │ │ │ │ │ sz/min,max │ │ │ │ │ │ │ │ nr_accesses/min,max │ │ │ │ │ │ │ │ age/min,max │ │ │ │ │ │ │ quotas/ms,bytes,reset_interval_ms │ │ │ │ │ │ │ │ weights/sz_permil,nr_accesses_permil,age_permil │ │ │ │ │ │ │ watermarks/metric,interval_us,high,mid,low │ │ │ │ │ │ │ stats/nr_tried,sz_tried,nr_applied,sz_applied,qt_exceeds │ │ │ │ │ │ ... │ │ │ │ ... │ │ ... Detailed usage of the files will be described in the final Documentation patch of this patchset. Main Difference Between DAMON_DBGFS and DAMON_SYSFS --------------------------------------------------- At the moment, DAMON_DBGFS and DAMON_SYSFS provides same features. One important difference between them is their exclusiveness. DAMON_DBGFS works in an exclusive manner, so that no DAMON worker thread (kdamond) in the system can run concurrently and interfere somehow. For the reason, DAMON_DBGFS asks users to construct all monitoring contexts and start them at once. It's not a big problem but makes the operation a little bit complex and unflexible. For more flexible usage, DAMON_SYSFS moves the responsibility of preventing any possible interference to the admins and work in a non-exclusive manner. That is, users can configure and start contexts one by one. Note that DAMON respects both exclusive groups and non-exclusive groups of contexts, in a manner similar to that of reader-writer locks. That is, if any exclusive monitoring contexts (e.g., contexts that started via DAMON_DBGFS) are running, DAMON_SYSFS does not start new contexts, and vice versa. Future Plan of DAMON_DBGFS Deprecation ====================================== Once this patchset is merged, DAMON_DBGFS development will be frozen. That is, we will maintain it to work as is now so that no users will be break. But, it will not be extended to provide any new feature of DAMON. The support will be continued only until next LTS release. After that, we will drop DAMON_DBGFS. User-space Tooling Compatibility -------------------------------- As DAMON_SYSFS provides all features of DAMON_DBGFS, all user space tooling can move to DAMON_SYSFS. As we will continue supporting DAMON_DBGFS until next LTS kernel release, user space tools would have enough time to move to DAMON_SYSFS. The official user space tool, damo[1], is already supporting both DAMON_SYSFS and DAMON_DBGFS. Both correctness tests[2] and performance tests[3] of DAMON using DAMON_SYSFS also passed. [1] https://github.com/awslabs/damo [2] https://github.com/awslabs/damon-tests/tree/master/corr [3] https://github.com/awslabs/damon-tests/tree/master/perf Sequence of Patches =================== First two patches (patches 1-2) make core changes for DAMON_SYSFS. The first one (patch 1) allows non-exclusive DAMON contexts so that DAMON_SYSFS can work in non-exclusive mode, while the second one (patch 2) adds size of DAMON enum types so that DAMON API users can safely iterate the enums. Third patch (patch 3) implements basic sysfs stub for virtual address spaces monitoring. Note that this implements only sysfs files and DAMON is not linked. Fourth patch (patch 4) links the DAMON_SYSFS to DAMON so that users can control DAMON using the sysfs files. Following six patches (patches 5-10) implements other DAMON features that DAMON_DBGFS supports one by one (physical address space monitoring, DAMON-based operation schemes, schemes quotas, schemes prioritization weights, schemes watermarks, and schemes stats). Following patch (patch 11) adds a simple selftest for DAMON_SYSFS, and the final one (patch 12) documents DAMON_SYSFS. This patch (of 13): To avoid interference between DAMON contexts monitoring overlapping memory regions, damon_start() works in an exclusive manner. That is, damon_start() does nothing bug fails if any context that started by another instance of the function is still running. This makes its usage a little bit restrictive. However, admins could aware each DAMON usage and address such interferences on their own in some cases. This commit hence implements non-exclusive mode of the function and allows the callers to select the mode. Note that the exclusive groups and non-exclusive groups of contexts will respect each other in a manner similar to that of reader-writer locks. Therefore, this commit will not cause any behavioral change to the exclusive groups. Link: https://lkml.kernel.org/r/20220228081314.5770-1-sj@kernel.org Link: https://lkml.kernel.org/r/20220228081314.5770-2-sj@kernel.org Signed-off-by: SeongJae Park Cc: Jonathan Corbet Cc: Shuah Khan Cc: David Rientjes Cc: Xin Hao Cc: Greg Kroah-Hartman Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/damon.h | 2 +- mm/damon/core.c | 23 +++++++++++++++-------- mm/damon/dbgfs.c | 2 +- mm/damon/reclaim.c | 2 +- 4 files changed, 18 insertions(+), 11 deletions(-) (limited to 'include/linux') diff --git a/include/linux/damon.h b/include/linux/damon.h index 49c4a11ecf20..f8e99e47d747 100644 --- a/include/linux/damon.h +++ b/include/linux/damon.h @@ -508,7 +508,7 @@ int damon_nr_running_ctxs(void); int damon_register_ops(struct damon_operations *ops); int damon_select_ops(struct damon_ctx *ctx, enum damon_ops_id id); -int damon_start(struct damon_ctx **ctxs, int nr_ctxs); +int damon_start(struct damon_ctx **ctxs, int nr_ctxs, bool exclusive); int damon_stop(struct damon_ctx **ctxs, int nr_ctxs); #endif /* CONFIG_DAMON */ diff --git a/mm/damon/core.c b/mm/damon/core.c index 82e0a4620c4f..c1e0fed4e877 100644 --- a/mm/damon/core.c +++ b/mm/damon/core.c @@ -24,6 +24,7 @@ static DEFINE_MUTEX(damon_lock); static int nr_running_ctxs; +static bool running_exclusive_ctxs; static DEFINE_MUTEX(damon_ops_lock); static struct damon_operations damon_registered_ops[NR_DAMON_OPS]; @@ -434,22 +435,25 @@ static int __damon_start(struct damon_ctx *ctx) * damon_start() - Starts the monitorings for a given group of contexts. * @ctxs: an array of the pointers for contexts to start monitoring * @nr_ctxs: size of @ctxs + * @exclusive: exclusiveness of this contexts group * * This function starts a group of monitoring threads for a group of monitoring * contexts. One thread per each context is created and run in parallel. The - * caller should handle synchronization between the threads by itself. If a - * group of threads that created by other 'damon_start()' call is currently - * running, this function does nothing but returns -EBUSY. + * caller should handle synchronization between the threads by itself. If + * @exclusive is true and a group of threads that created by other + * 'damon_start()' call is currently running, this function does nothing but + * returns -EBUSY. * * Return: 0 on success, negative error code otherwise. */ -int damon_start(struct damon_ctx **ctxs, int nr_ctxs) +int damon_start(struct damon_ctx **ctxs, int nr_ctxs, bool exclusive) { int i; int err = 0; mutex_lock(&damon_lock); - if (nr_running_ctxs) { + if ((exclusive && nr_running_ctxs) || + (!exclusive && running_exclusive_ctxs)) { mutex_unlock(&damon_lock); return -EBUSY; } @@ -460,13 +464,15 @@ int damon_start(struct damon_ctx **ctxs, int nr_ctxs) break; nr_running_ctxs++; } + if (exclusive && nr_running_ctxs) + running_exclusive_ctxs = true; mutex_unlock(&damon_lock); return err; } /* - * __damon_stop() - Stops monitoring of given context. + * __damon_stop() - Stops monitoring of a given context. * @ctx: monitoring context * * Return: 0 on success, negative error code otherwise. @@ -504,9 +510,8 @@ int damon_stop(struct damon_ctx **ctxs, int nr_ctxs) /* nr_running_ctxs is decremented in kdamond_fn */ err = __damon_stop(ctxs[i]); if (err) - return err; + break; } - return err; } @@ -1102,6 +1107,8 @@ static int kdamond_fn(void *data) mutex_lock(&damon_lock); nr_running_ctxs--; + if (!nr_running_ctxs && running_exclusive_ctxs) + running_exclusive_ctxs = false; mutex_unlock(&damon_lock); return 0; diff --git a/mm/damon/dbgfs.c b/mm/damon/dbgfs.c index 05b574cbcea8..a0dab8b5e45f 100644 --- a/mm/damon/dbgfs.c +++ b/mm/damon/dbgfs.c @@ -967,7 +967,7 @@ static ssize_t dbgfs_monitor_on_write(struct file *file, return -EINVAL; } } - ret = damon_start(dbgfs_ctxs, dbgfs_nr_ctxs); + ret = damon_start(dbgfs_ctxs, dbgfs_nr_ctxs, true); } else if (!strncmp(kbuf, "off", count)) { ret = damon_stop(dbgfs_ctxs, dbgfs_nr_ctxs); } else { diff --git a/mm/damon/reclaim.c b/mm/damon/reclaim.c index b53d9c22fad1..e34c4d0c4d93 100644 --- a/mm/damon/reclaim.c +++ b/mm/damon/reclaim.c @@ -330,7 +330,7 @@ static int damon_reclaim_turn(bool on) if (err) goto free_scheme_out; - err = damon_start(&ctx, 1); + err = damon_start(&ctx, 1, true); if (!err) { kdamond_pid = ctx->kdamond->pid; return 0; -- cgit v1.2.3 From 5257f36ec289d544532f2889cbed11abbb06cf0c Mon Sep 17 00:00:00 2001 From: SeongJae Park Date: Tue, 22 Mar 2022 14:49:24 -0700 Subject: mm/damon/core: add number of each enum type values This commit declares the number of legal values for each DAMON enum types to make traversals of such DAMON enum types easy and safe. Link: https://lkml.kernel.org/r/20220228081314.5770-3-sj@kernel.org Signed-off-by: SeongJae Park Cc: David Rientjes Cc: Greg Kroah-Hartman Cc: Jonathan Corbet Cc: Shuah Khan Cc: Xin Hao Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/damon.h | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'include/linux') diff --git a/include/linux/damon.h b/include/linux/damon.h index f8e99e47d747..f23cbfa4248d 100644 --- a/include/linux/damon.h +++ b/include/linux/damon.h @@ -87,6 +87,7 @@ struct damon_target { * @DAMOS_HUGEPAGE: Call ``madvise()`` for the region with MADV_HUGEPAGE. * @DAMOS_NOHUGEPAGE: Call ``madvise()`` for the region with MADV_NOHUGEPAGE. * @DAMOS_STAT: Do nothing but count the stat. + * @NR_DAMOS_ACTIONS: Total number of DAMOS actions */ enum damos_action { DAMOS_WILLNEED, @@ -95,6 +96,7 @@ enum damos_action { DAMOS_HUGEPAGE, DAMOS_NOHUGEPAGE, DAMOS_STAT, /* Do nothing but only record the stat */ + NR_DAMOS_ACTIONS, }; /** @@ -157,10 +159,12 @@ struct damos_quota { * * @DAMOS_WMARK_NONE: Ignore the watermarks of the given scheme. * @DAMOS_WMARK_FREE_MEM_RATE: Free memory rate of the system in [0,1000]. + * @NR_DAMOS_WMARK_METRICS: Total number of DAMOS watermark metrics */ enum damos_wmark_metric { DAMOS_WMARK_NONE, DAMOS_WMARK_FREE_MEM_RATE, + NR_DAMOS_WMARK_METRICS, }; /** -- cgit v1.2.3