2 * include/asm-s390/semaphore.h
5 * Copyright (C) 1999 IBM Deutschland Entwicklung GmbH, IBM Corporation
7 * Derived from "include/asm-i386/semaphore.h"
8 * (C) Copyright 1996 Linus Torvalds
11 #ifndef _S390_SEMAPHORE_H
12 #define _S390_SEMAPHORE_H
14 #include <asm/system.h>
15 #include <asm/atomic.h>
16 #include <linux/wait.h>
17 #include <linux/rwsem.h>
22 wait_queue_head_t wait;
25 #define __SEM_DEBUG_INIT(name)
27 #define __SEMAPHORE_INITIALIZER(name,count) \
28 { ATOMIC_INIT(count), 0, __WAIT_QUEUE_HEAD_INITIALIZER((name).wait) \
29 __SEM_DEBUG_INIT(name) }
31 #define __MUTEX_INITIALIZER(name) \
32 __SEMAPHORE_INITIALIZER(name,1)
34 #define __DECLARE_SEMAPHORE_GENERIC(name,count) \
35 struct semaphore name = __SEMAPHORE_INITIALIZER(name,count)
37 #define DECLARE_MUTEX(name) __DECLARE_SEMAPHORE_GENERIC(name,1)
38 #define DECLARE_MUTEX_LOCKED(name) __DECLARE_SEMAPHORE_GENERIC(name,0)
40 static inline void sema_init (struct semaphore *sem, int val)
42 *sem = (struct semaphore)__SEMAPHORE_INITIALIZER((*sem),val);
45 static inline void init_MUTEX (struct semaphore *sem)
50 static inline void init_MUTEX_LOCKED (struct semaphore *sem)
55 asmlinkage void __down_failed(void /* special register calling convention */);
56 asmlinkage int __down_failed_interruptible(void /* params in registers */);
57 asmlinkage int __down_failed_trylock(void /* params in registers */);
58 asmlinkage void __up_wakeup(void /* special register calling convention */);
60 asmlinkage void __down(struct semaphore * sem);
61 asmlinkage int __down_interruptible(struct semaphore * sem);
62 asmlinkage int __down_trylock(struct semaphore * sem);
63 asmlinkage void __up(struct semaphore * sem);
65 static inline void down(struct semaphore * sem)
67 if (atomic_dec_return(&sem->count) < 0)
71 static inline int down_interruptible(struct semaphore * sem)
75 if (atomic_dec_return(&sem->count) < 0)
76 ret = __down_interruptible(sem);
80 static inline int down_trylock(struct semaphore * sem)
84 if (atomic_dec_return(&sem->count) < 0)
85 ret = __down_trylock(sem);
89 static inline void up(struct semaphore * sem)
91 if (atomic_inc_return(&sem->count) <= 0)
95 static inline int sem_getcount(struct semaphore *sem)
97 return atomic_read(&sem->count);