You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
101 lines
2.1 KiB
101 lines
2.1 KiB
20 years ago
|
#ifndef _ASM_IA64_SEMAPHORE_H
|
||
|
#define _ASM_IA64_SEMAPHORE_H
|
||
|
|
||
|
/*
|
||
|
* Copyright (C) 1998-2000 Hewlett-Packard Co
|
||
|
* Copyright (C) 1998-2000 David Mosberger-Tang <davidm@hpl.hp.com>
|
||
|
*/
|
||
|
|
||
|
#include <linux/wait.h>
|
||
|
#include <linux/rwsem.h>
|
||
|
|
||
|
#include <asm/atomic.h>
|
||
|
|
||
|
struct semaphore {
|
||
|
atomic_t count;
|
||
|
int sleepers;
|
||
|
wait_queue_head_t wait;
|
||
|
};
|
||
|
|
||
|
#define __SEMAPHORE_INITIALIZER(name, n) \
|
||
|
{ \
|
||
|
.count = ATOMIC_INIT(n), \
|
||
|
.sleepers = 0, \
|
||
|
.wait = __WAIT_QUEUE_HEAD_INITIALIZER((name).wait) \
|
||
|
}
|
||
|
|
||
|
#define __DECLARE_SEMAPHORE_GENERIC(name,count) \
|
||
|
struct semaphore name = __SEMAPHORE_INITIALIZER(name, count)
|
||
|
|
||
|
#define DECLARE_MUTEX(name) __DECLARE_SEMAPHORE_GENERIC(name, 1)
|
||
|
#define DECLARE_MUTEX_LOCKED(name) __DECLARE_SEMAPHORE_GENERIC(name, 0)
|
||
|
|
||
|
static inline void
|
||
|
sema_init (struct semaphore *sem, int val)
|
||
|
{
|
||
|
*sem = (struct semaphore) __SEMAPHORE_INITIALIZER(*sem, val);
|
||
|
}
|
||
|
|
||
|
static inline void
|
||
|
init_MUTEX (struct semaphore *sem)
|
||
|
{
|
||
|
sema_init(sem, 1);
|
||
|
}
|
||
|
|
||
|
static inline void
|
||
|
init_MUTEX_LOCKED (struct semaphore *sem)
|
||
|
{
|
||
|
sema_init(sem, 0);
|
||
|
}
|
||
|
|
||
|
extern void __down (struct semaphore * sem);
|
||
|
extern int __down_interruptible (struct semaphore * sem);
|
||
|
extern int __down_trylock (struct semaphore * sem);
|
||
|
extern void __up (struct semaphore * sem);
|
||
|
|
||
|
/*
|
||
|
* Atomically decrement the semaphore's count. If it goes negative,
|
||
|
* block the calling thread in the TASK_UNINTERRUPTIBLE state.
|
||
|
*/
|
||
|
static inline void
|
||
|
down (struct semaphore *sem)
|
||
|
{
|
||
|
might_sleep();
|
||
|
if (atomic_dec_return(&sem->count) < 0)
|
||
|
__down(sem);
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* Atomically decrement the semaphore's count. If it goes negative,
|
||
|
* block the calling thread in the TASK_INTERRUPTIBLE state.
|
||
|
*/
|
||
|
static inline int
|
||
|
down_interruptible (struct semaphore * sem)
|
||
|
{
|
||
|
int ret = 0;
|
||
|
|
||
|
might_sleep();
|
||
|
if (atomic_dec_return(&sem->count) < 0)
|
||
|
ret = __down_interruptible(sem);
|
||
|
return ret;
|
||
|
}
|
||
|
|
||
|
static inline int
|
||
|
down_trylock (struct semaphore *sem)
|
||
|
{
|
||
|
int ret = 0;
|
||
|
|
||
|
if (atomic_dec_return(&sem->count) < 0)
|
||
|
ret = __down_trylock(sem);
|
||
|
return ret;
|
||
|
}
|
||
|
|
||
|
static inline void
|
||
|
up (struct semaphore * sem)
|
||
|
{
|
||
|
if (atomic_inc_return(&sem->count) <= 0)
|
||
|
__up(sem);
|
||
|
}
|
||
|
|
||
|
#endif /* _ASM_IA64_SEMAPHORE_H */
|