From ea65b41807a26495ff2a73dd8b1bab2751940887 Mon Sep 17 00:00:00 2001 From: John Keeping Date: Mon, 27 Mar 2023 18:36:46 +0100 Subject: ftrace: Mark get_lock_parent_ip() __always_inline If the compiler decides not to inline this function then preemption tracing will always show an IP inside the preemption disabling path and never the function actually calling preempt_{enable,disable}. Link: https://lore.kernel.org/linux-trace-kernel/20230327173647.1690849-1-john@metanate.com Cc: Masami Hiramatsu Cc: Mark Rutland Cc: stable@vger.kernel.org Fixes: f904f58263e1d ("sched/debug: Fix preempt_disable_ip recording for preempt_disable()") Signed-off-by: John Keeping Signed-off-by: Steven Rostedt (Google) --- include/linux/ftrace.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include') diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h index 366c730beaa3..402fc061de75 100644 --- a/include/linux/ftrace.h +++ b/include/linux/ftrace.h @@ -980,7 +980,7 @@ static inline void __ftrace_enabled_restore(int enabled) #define CALLER_ADDR5 ((unsigned long)ftrace_return_address(5)) #define CALLER_ADDR6 ((unsigned long)ftrace_return_address(6)) -static inline unsigned long get_lock_parent_ip(void) +static __always_inline unsigned long get_lock_parent_ip(void) { unsigned long addr = CALLER_ADDR0; -- cgit v1.2.3 From f82e7ca019dfad3b006fd3b772f7ac569672db55 Mon Sep 17 00:00:00 2001 From: "Steven Rostedt (Google)" Date: Thu, 9 Mar 2023 22:13:02 -0500 Subject: tracing: Error if a trace event has an array for a __field() A __field() in the TRACE_EVENT() macro is used to set up the fields of the trace event data. It is for single storage units (word, char, int, pointer, etc) and not for complex structures or arrays. Unfortunately, there's nothing preventing the build from accepting: __field(int, arr[5]); from building. It will turn into a array value. This use to work fine, as the offset and size use to be determined by the macro using the field name, but things have changed and the offset and size are now determined by the type. So the above would only be size 4, and the next field will be located 4 bytes from it (instead of 20). The proper way to declare static arrays is to use the __array() macro. Instead of __field(int, arr[5]) it should be __array(int, arr, 5). Add some macro tricks to the building of a trace event from the TRACE_EVENT() macro such that __field(int, arr[5]) will fail to build. A comment by the failure will explain why the build failed. Link: https://lore.kernel.org/lkml/20230306122549.236561-1-douglas.raillard@arm.com/ Link: https://lore.kernel.org/linux-trace-kernel/20230309221302.642e82d9@gandalf.local.home Reported-by: Douglas RAILLARD Signed-off-by: Steven Rostedt (Google) Acked-by: Masami Hiramatsu (Google) --- include/trace/stages/stage5_get_offsets.h | 21 +++++++++++++++++---- 1 file changed, 17 insertions(+), 4 deletions(-) (limited to 'include') diff --git a/include/trace/stages/stage5_get_offsets.h b/include/trace/stages/stage5_get_offsets.h index ac5c24d3beeb..e30a13be46ba 100644 --- a/include/trace/stages/stage5_get_offsets.h +++ b/include/trace/stages/stage5_get_offsets.h @@ -9,17 +9,30 @@ #undef __entry #define __entry entry +/* + * Fields should never declare an array: i.e. __field(int, arr[5]) + * If they do, it will cause issues in parsing and possibly corrupt the + * events. To prevent that from happening, test the sizeof() a fictitious + * type called "struct _test_no_array_##item" which will fail if "item" + * contains array elements (like "arr[5]"). + * + * If you hit this, use __array(int, arr, 5) instead. + */ #undef __field -#define __field(type, item) +#define __field(type, item) \ + { (void)sizeof(struct _test_no_array_##item *); } #undef __field_ext -#define __field_ext(type, item, filter_type) +#define __field_ext(type, item, filter_type) \ + { (void)sizeof(struct _test_no_array_##item *); } #undef __field_struct -#define __field_struct(type, item) +#define __field_struct(type, item) \ + { (void)sizeof(struct _test_no_array_##item *); } #undef __field_struct_ext -#define __field_struct_ext(type, item, filter_type) +#define __field_struct_ext(type, item, filter_type) \ + { (void)sizeof(struct _test_no_array_##item *); } #undef __array #define __array(type, item, len) -- cgit v1.2.3