Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1#ifndef __LINUX_RWLOCK_H
2#define __LINUX_RWLOCK_H
3
4#ifndef __LINUX_INSIDE_SPINLOCK_H
5# error "Please do not include this file directly."
6#endif
7
8/*
9 * rwlock related methods
10 *
11 * split out from spinlock.h
12 *
13 * portions Copyright 2005, Red Hat, Inc., Ingo Molnar
14 * Released under the General Public License (GPL).
15 */
16
17#ifdef CONFIG_DEBUG_SPINLOCK
18 extern void __rwlock_init(rwlock_t *lock, const char *name,
19 struct lock_class_key *key);
20# define rwlock_init(lock) \
21do { \
22 static struct lock_class_key __key; \
23 \
24 __rwlock_init((lock), #lock, &__key); \
25} while (0)
26#else
27# define rwlock_init(lock) \
28 do { *(lock) = __RW_LOCK_UNLOCKED(lock); } while (0)
29#endif
30
31#ifdef CONFIG_DEBUG_SPINLOCK
32 extern void do_raw_read_lock(rwlock_t *lock) __acquires_shared(lock);
33 extern int do_raw_read_trylock(rwlock_t *lock) __cond_acquires_shared(true, lock);
34 extern void do_raw_read_unlock(rwlock_t *lock) __releases_shared(lock);
35 extern void do_raw_write_lock(rwlock_t *lock) __acquires(lock);
36extern int do_raw_write_trylock(rwlock_t *lock) __cond_acquires(true, lock);
37 extern void do_raw_write_unlock(rwlock_t *lock) __releases(lock);
38#else
39# define do_raw_read_lock(rwlock) do {__acquire_shared(lock); arch_read_lock(&(rwlock)->raw_lock); } while (0)
40static inline int do_raw_read_trylock(rwlock_t *rwlock)
41 __cond_acquires_shared(true, rwlock)
42 __no_context_analysis
43{
44 return arch_read_trylock(&(rwlock)->raw_lock);
45}
46# define do_raw_read_unlock(rwlock) do {arch_read_unlock(&(rwlock)->raw_lock); __release_shared(lock); } while (0)
47# define do_raw_write_lock(rwlock) do {__acquire(lock); arch_write_lock(&(rwlock)->raw_lock); } while (0)
48static inline int do_raw_write_trylock(rwlock_t *rwlock)
49 __cond_acquires(true, rwlock)
50 __no_context_analysis
51{
52 return arch_write_trylock(&(rwlock)->raw_lock);
53}
54# define do_raw_write_unlock(rwlock) do {arch_write_unlock(&(rwlock)->raw_lock); __release(lock); } while (0)
55#endif
56
57/*
58 * Define the various rw_lock methods. Note we define these
59 * regardless of whether CONFIG_SMP or CONFIG_PREEMPT are set. The various
60 * methods are defined as nops in the case they are not required.
61 */
62#define read_trylock(lock) _raw_read_trylock(lock)
63#define write_trylock(lock) _raw_write_trylock(lock)
64
65#define write_lock(lock) _raw_write_lock(lock)
66#define read_lock(lock) _raw_read_lock(lock)
67
68#ifdef CONFIG_DEBUG_LOCK_ALLOC
69#define write_lock_nested(lock, subclass) _raw_write_lock_nested(lock, subclass)
70#else
71#define write_lock_nested(lock, subclass) _raw_write_lock(lock)
72#endif
73
74#if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_SPINLOCK)
75
76#define read_lock_irqsave(lock, flags) \
77 do { \
78 typecheck(unsigned long, flags); \
79 flags = _raw_read_lock_irqsave(lock); \
80 } while (0)
81#define write_lock_irqsave(lock, flags) \
82 do { \
83 typecheck(unsigned long, flags); \
84 flags = _raw_write_lock_irqsave(lock); \
85 } while (0)
86
87#else
88
89#define read_lock_irqsave(lock, flags) \
90 do { \
91 typecheck(unsigned long, flags); \
92 _raw_read_lock_irqsave(lock, flags); \
93 } while (0)
94#define write_lock_irqsave(lock, flags) \
95 do { \
96 typecheck(unsigned long, flags); \
97 _raw_write_lock_irqsave(lock, flags); \
98 } while (0)
99
100#endif
101
102#define read_lock_irq(lock) _raw_read_lock_irq(lock)
103#define read_lock_bh(lock) _raw_read_lock_bh(lock)
104#define write_lock_irq(lock) _raw_write_lock_irq(lock)
105#define write_lock_bh(lock) _raw_write_lock_bh(lock)
106#define read_unlock(lock) _raw_read_unlock(lock)
107#define write_unlock(lock) _raw_write_unlock(lock)
108#define read_unlock_irq(lock) _raw_read_unlock_irq(lock)
109#define write_unlock_irq(lock) _raw_write_unlock_irq(lock)
110
111#define read_unlock_irqrestore(lock, flags) \
112 do { \
113 typecheck(unsigned long, flags); \
114 _raw_read_unlock_irqrestore(lock, flags); \
115 } while (0)
116#define read_unlock_bh(lock) _raw_read_unlock_bh(lock)
117
118#define write_unlock_irqrestore(lock, flags) \
119 do { \
120 typecheck(unsigned long, flags); \
121 _raw_write_unlock_irqrestore(lock, flags); \
122 } while (0)
123#define write_unlock_bh(lock) _raw_write_unlock_bh(lock)
124
125#define write_trylock_irqsave(lock, flags) _raw_write_trylock_irqsave(lock, &(flags))
126
127#ifdef arch_rwlock_is_contended
128#define rwlock_is_contended(lock) \
129 arch_rwlock_is_contended(&(lock)->raw_lock)
130#else
131#define rwlock_is_contended(lock) ((void)(lock), 0)
132#endif /* arch_rwlock_is_contended */
133
134#endif /* __LINUX_RWLOCK_H */