1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
|
/*-
* Copyright (c) 2008-2012 WiredTiger, Inc.
* All rights reserved.
*
* See the file LICENSE for redistribution information.
*/
/*
* Spin locks:
*
* These used for cases where fast mutual exclusion is needed (where operations
* done while holding the spin lock are expected to complete in a small number
* of instructions.
*/
#if SPINLOCK_TYPE == SPINLOCK_GCC
static inline void
__wt_spin_init(WT_SESSION_IMPL *session, WT_SPINLOCK *t)
{
WT_UNUSED(session);
*(t) = 0;
}
static inline void
__wt_spin_destroy(WT_SESSION_IMPL *session, WT_SPINLOCK *t)
{
WT_UNUSED(session);
WT_UNUSED(t);
}
static inline void
__wt_spin_lock(WT_SESSION_IMPL *session, WT_SPINLOCK *t)
{
WT_UNUSED(session);
while (__sync_lock_test_and_set(t, 1))
while (*t)
WT_PAUSE();
}
static inline int
__wt_spin_trylock(WT_SESSION_IMPL *session, WT_SPINLOCK *t)
{
WT_UNUSED(session);
return (!__sync_lock_test_and_set(t, 1));
}
static inline void
__wt_spin_unlock(WT_SESSION_IMPL *session, WT_SPINLOCK *t)
{
WT_UNUSED(session);
__sync_lock_release(t);
}
#elif SPINLOCK_TYPE == SPINLOCK_PTHREAD_MUTEX
static inline void
__wt_spin_init(WT_SESSION_IMPL *session, WT_SPINLOCK *t)
{
WT_UNUSED(session);
(void)pthread_mutex_init(t, NULL);
}
static inline void
__wt_spin_destroy(WT_SESSION_IMPL *session, WT_SPINLOCK *t)
{
WT_UNUSED(session);
(void)pthread_mutex_destroy(t);
}
static inline void
__wt_spin_lock(WT_SESSION_IMPL *session, WT_SPINLOCK *t)
{
WT_UNUSED(session);
pthread_mutex_lock(t);
}
static inline int
__wt_spin_trylock(WT_SESSION_IMPL *session, WT_SPINLOCK *t)
{
WT_UNUSED(session);
return (pthread_mutex_trylock(t));
}
static inline void
__wt_spin_unlock(WT_SESSION_IMPL *session, WT_SPINLOCK *t)
{
WT_UNUSED(session);
pthread_mutex_unlock(t);
}
#else
#error Unknown spinlock type
#endif
|
