1 | #ifndef __LINUX_RWLOCK_H |
2 | #define __LINUX_RWLOCK_H |
3 | |
4 | #ifndef __LINUX_INSIDE_SPINLOCK_H |
5 | # error "please don't 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) \ |
21 | do { \ |
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(lock); |
33 | extern int do_raw_read_trylock(rwlock_t *lock); |
34 | extern void do_raw_read_unlock(rwlock_t *lock) __releases(lock); |
35 | extern void do_raw_write_lock(rwlock_t *lock) __acquires(lock); |
36 | extern int do_raw_write_trylock(rwlock_t *lock); |
37 | extern void do_raw_write_unlock(rwlock_t *lock) __releases(lock); |
38 | #else |
39 | # define do_raw_read_lock(rwlock) do {__acquire(lock); arch_read_lock(&(rwlock)->raw_lock); } while (0) |
40 | # define do_raw_read_trylock(rwlock) arch_read_trylock(&(rwlock)->raw_lock) |
41 | # define do_raw_read_unlock(rwlock) do {arch_read_unlock(&(rwlock)->raw_lock); __release(lock); } while (0) |
42 | # define do_raw_write_lock(rwlock) do {__acquire(lock); arch_write_lock(&(rwlock)->raw_lock); } while (0) |
43 | # define do_raw_write_trylock(rwlock) arch_write_trylock(&(rwlock)->raw_lock) |
44 | # define do_raw_write_unlock(rwlock) do {arch_write_unlock(&(rwlock)->raw_lock); __release(lock); } while (0) |
45 | #endif |
46 | |
47 | /* |
48 | * Define the various rw_lock methods. Note we define these |
49 | * regardless of whether CONFIG_SMP or CONFIG_PREEMPT are set. The various |
50 | * methods are defined as nops in the case they are not required. |
51 | */ |
52 | #define read_trylock(lock) __cond_lock(lock, _raw_read_trylock(lock)) |
53 | #define write_trylock(lock) __cond_lock(lock, _raw_write_trylock(lock)) |
54 | |
55 | #define write_lock(lock) _raw_write_lock(lock) |
56 | #define read_lock(lock) _raw_read_lock(lock) |
57 | |
58 | #ifdef CONFIG_DEBUG_LOCK_ALLOC |
59 | #define write_lock_nested(lock, subclass) _raw_write_lock_nested(lock, subclass) |
60 | #else |
61 | #define write_lock_nested(lock, subclass) _raw_write_lock(lock) |
62 | #endif |
63 | |
64 | #if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_SPINLOCK) |
65 | |
66 | #define read_lock_irqsave(lock, flags) \ |
67 | do { \ |
68 | typecheck(unsigned long, flags); \ |
69 | flags = _raw_read_lock_irqsave(lock); \ |
70 | } while (0) |
71 | #define write_lock_irqsave(lock, flags) \ |
72 | do { \ |
73 | typecheck(unsigned long, flags); \ |
74 | flags = _raw_write_lock_irqsave(lock); \ |
75 | } while (0) |
76 | |
77 | #else |
78 | |
79 | #define read_lock_irqsave(lock, flags) \ |
80 | do { \ |
81 | typecheck(unsigned long, flags); \ |
82 | _raw_read_lock_irqsave(lock, flags); \ |
83 | } while (0) |
84 | #define write_lock_irqsave(lock, flags) \ |
85 | do { \ |
86 | typecheck(unsigned long, flags); \ |
87 | _raw_write_lock_irqsave(lock, flags); \ |
88 | } while (0) |
89 | |
90 | #endif |
91 | |
92 | #define read_lock_irq(lock) _raw_read_lock_irq(lock) |
93 | #define read_lock_bh(lock) _raw_read_lock_bh(lock) |
94 | #define write_lock_irq(lock) _raw_write_lock_irq(lock) |
95 | #define write_lock_bh(lock) _raw_write_lock_bh(lock) |
96 | #define read_unlock(lock) _raw_read_unlock(lock) |
97 | #define write_unlock(lock) _raw_write_unlock(lock) |
98 | #define read_unlock_irq(lock) _raw_read_unlock_irq(lock) |
99 | #define write_unlock_irq(lock) _raw_write_unlock_irq(lock) |
100 | |
101 | #define read_unlock_irqrestore(lock, flags) \ |
102 | do { \ |
103 | typecheck(unsigned long, flags); \ |
104 | _raw_read_unlock_irqrestore(lock, flags); \ |
105 | } while (0) |
106 | #define read_unlock_bh(lock) _raw_read_unlock_bh(lock) |
107 | |
108 | #define write_unlock_irqrestore(lock, flags) \ |
109 | do { \ |
110 | typecheck(unsigned long, flags); \ |
111 | _raw_write_unlock_irqrestore(lock, flags); \ |
112 | } while (0) |
113 | #define write_unlock_bh(lock) _raw_write_unlock_bh(lock) |
114 | |
115 | #define write_trylock_irqsave(lock, flags) \ |
116 | ({ \ |
117 | local_irq_save(flags); \ |
118 | write_trylock(lock) ? \ |
119 | 1 : ({ local_irq_restore(flags); 0; }); \ |
120 | }) |
121 | |
122 | #ifdef arch_rwlock_is_contended |
123 | #define rwlock_is_contended(lock) \ |
124 | arch_rwlock_is_contended(&(lock)->raw_lock) |
125 | #else |
126 | #define rwlock_is_contended(lock) ((void)(lock), 0) |
127 | #endif /* arch_rwlock_is_contended */ |
128 | |
129 | #endif /* __LINUX_RWLOCK_H */ |
130 | |