fs: use kmem_cache_zalloc instead
[pv_ops_mirror.git] / include / asm-arm / semaphore.h
blob1c8b441f89e300c6c46dda9bcf6c707a38ceca66
1 /*
2 * linux/include/asm-arm/semaphore.h
3 */
4 #ifndef __ASM_ARM_SEMAPHORE_H
5 #define __ASM_ARM_SEMAPHORE_H
7 #include <linux/linkage.h>
8 #include <linux/spinlock.h>
9 #include <linux/wait.h>
10 #include <linux/rwsem.h>
12 #include <asm/atomic.h>
13 #include <asm/locks.h>
15 struct semaphore {
16 atomic_t count;
17 int sleepers;
18 wait_queue_head_t wait;
21 #define __SEMAPHORE_INIT(name, cnt) \
22 { \
23 .count = ATOMIC_INIT(cnt), \
24 .wait = __WAIT_QUEUE_HEAD_INITIALIZER((name).wait), \
27 #define __DECLARE_SEMAPHORE_GENERIC(name,count) \
28 struct semaphore name = __SEMAPHORE_INIT(name,count)
30 #define DECLARE_MUTEX(name) __DECLARE_SEMAPHORE_GENERIC(name,1)
32 static inline void sema_init(struct semaphore *sem, int val)
34 atomic_set(&sem->count, val);
35 sem->sleepers = 0;
36 init_waitqueue_head(&sem->wait);
39 static inline void init_MUTEX(struct semaphore *sem)
41 sema_init(sem, 1);
44 static inline void init_MUTEX_LOCKED(struct semaphore *sem)
46 sema_init(sem, 0);
50 * special register calling convention
52 asmlinkage void __down_failed(void);
53 asmlinkage int __down_interruptible_failed(void);
54 asmlinkage int __down_trylock_failed(void);
55 asmlinkage void __up_wakeup(void);
57 extern void __down(struct semaphore * sem);
58 extern int __down_interruptible(struct semaphore * sem);
59 extern int __down_trylock(struct semaphore * sem);
60 extern void __up(struct semaphore * sem);
63 * This is ugly, but we want the default case to fall through.
64 * "__down" is the actual routine that waits...
66 static inline void down(struct semaphore * sem)
68 might_sleep();
69 __down_op(sem, __down_failed);
73 * This is ugly, but we want the default case to fall through.
74 * "__down_interruptible" is the actual routine that waits...
76 static inline int down_interruptible (struct semaphore * sem)
78 might_sleep();
79 return __down_op_ret(sem, __down_interruptible_failed);
82 static inline int down_trylock(struct semaphore *sem)
84 return __down_op_ret(sem, __down_trylock_failed);
88 * Note! This is subtle. We jump to wake people up only if
89 * the semaphore was negative (== somebody was waiting on it).
90 * The default case (no contention) will result in NO
91 * jumps for both down() and up().
93 static inline void up(struct semaphore * sem)
95 __up_op(sem, __up_wakeup);
98 #endif