alistair23-linux/include/linux/semaphore.h
Tycho Andersen 2dd6fd2e99 locking/semaphore: Update the file path in documentation
While reading this header I noticed that the locking stuff has moved to
kernel/locking/*, so update the path in semaphore.h to point to that.

Signed-off-by: Tycho Andersen <tycho@tycho.ws>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20180201114119.1090-1-tycho@tycho.ws
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-02-13 15:00:06 +01:00

47 lines
1.4 KiB
C

/*
* Copyright (c) 2008 Intel Corporation
* Author: Matthew Wilcox <willy@linux.intel.com>
*
* Distributed under the terms of the GNU GPL, version 2
*
* Please see kernel/locking/semaphore.c for documentation of these functions
*/
#ifndef __LINUX_SEMAPHORE_H
#define __LINUX_SEMAPHORE_H
#include <linux/list.h>
#include <linux/spinlock.h>
/* Please don't access any members of this structure directly */
struct semaphore {
raw_spinlock_t lock;
unsigned int count;
struct list_head wait_list;
};
#define __SEMAPHORE_INITIALIZER(name, n) \
{ \
.lock = __RAW_SPIN_LOCK_UNLOCKED((name).lock), \
.count = n, \
.wait_list = LIST_HEAD_INIT((name).wait_list), \
}
#define DEFINE_SEMAPHORE(name) \
struct semaphore name = __SEMAPHORE_INITIALIZER(name, 1)
static inline void sema_init(struct semaphore *sem, int val)
{
static struct lock_class_key __key;
*sem = (struct semaphore) __SEMAPHORE_INITIALIZER(*sem, val);
lockdep_init_map(&sem->lock.dep_map, "semaphore->lock", &__key, 0);
}
extern void down(struct semaphore *sem);
extern int __must_check down_interruptible(struct semaphore *sem);
extern int __must_check down_killable(struct semaphore *sem);
extern int __must_check down_trylock(struct semaphore *sem);
extern int __must_check down_timeout(struct semaphore *sem, long jiffies);
extern void up(struct semaphore *sem);
#endif /* __LINUX_SEMAPHORE_H */