04fc8bbcf5
DECLARE_MUTEX_LOCKED was used for semaphores used as completions and we've got rid of them. Well, except for one in libusual that the maintainer explicitly wants to keep as semaphore. So convert that useage to an explicit sema_init and kill of DECLARE_MUTEX_LOCKED so that new code is reminded to use a completion. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: "Satyam Sharma" <satyam.sharma@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
100 lines
2.1 KiB
C
100 lines
2.1 KiB
C
/*
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* linux/include/asm-xtensa/semaphore.h
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*
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* This file is subject to the terms and conditions of the GNU General Public
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* License. See the file "COPYING" in the main directory of this archive
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* for more details.
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*
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* Copyright (C) 2001 - 2005 Tensilica Inc.
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*/
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#ifndef _XTENSA_SEMAPHORE_H
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#define _XTENSA_SEMAPHORE_H
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#include <asm/atomic.h>
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#include <asm/system.h>
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#include <linux/wait.h>
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#include <linux/rwsem.h>
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struct semaphore {
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atomic_t count;
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int sleepers;
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wait_queue_head_t wait;
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};
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#define __SEMAPHORE_INITIALIZER(name,n) \
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{ \
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.count = ATOMIC_INIT(n), \
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.sleepers = 0, \
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.wait = __WAIT_QUEUE_HEAD_INITIALIZER((name).wait) \
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}
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#define __DECLARE_SEMAPHORE_GENERIC(name,count) \
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struct semaphore name = __SEMAPHORE_INITIALIZER(name,count)
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#define DECLARE_MUTEX(name) __DECLARE_SEMAPHORE_GENERIC(name,1)
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static inline void sema_init (struct semaphore *sem, int val)
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{
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atomic_set(&sem->count, val);
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sem->sleepers = 0;
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init_waitqueue_head(&sem->wait);
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}
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static inline void init_MUTEX (struct semaphore *sem)
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{
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sema_init(sem, 1);
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}
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static inline void init_MUTEX_LOCKED (struct semaphore *sem)
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{
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sema_init(sem, 0);
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}
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asmlinkage void __down(struct semaphore * sem);
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asmlinkage int __down_interruptible(struct semaphore * sem);
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asmlinkage int __down_trylock(struct semaphore * sem);
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asmlinkage void __up(struct semaphore * sem);
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extern spinlock_t semaphore_wake_lock;
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static inline void down(struct semaphore * sem)
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{
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might_sleep();
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if (atomic_sub_return(1, &sem->count) < 0)
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__down(sem);
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}
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static inline int down_interruptible(struct semaphore * sem)
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{
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int ret = 0;
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might_sleep();
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if (atomic_sub_return(1, &sem->count) < 0)
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ret = __down_interruptible(sem);
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return ret;
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}
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static inline int down_trylock(struct semaphore * sem)
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{
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int ret = 0;
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if (atomic_sub_return(1, &sem->count) < 0)
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ret = __down_trylock(sem);
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return ret;
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}
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/*
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* Note! This is subtle. We jump to wake people up only if
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* the semaphore was negative (== somebody was waiting on it).
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*/
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static inline void up(struct semaphore * sem)
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{
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if (atomic_add_return(1, &sem->count) <= 0)
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__up(sem);
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}
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#endif /* _XTENSA_SEMAPHORE_H */
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