59 lines
1.3 KiB
C
59 lines
1.3 KiB
C
#ifndef __LINUX_MUTEX_H
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#define __LINUX_MUTEX_H
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#include <asm/semaphore.h>
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struct mutex {
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struct semaphore sema;
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};
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#define mutex_init(mutex) init_MUTEX(&mutex->sema)
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#define mutex_destroy(mutex) do { } while (0)
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#define DEFINE_MUTEX(mutexname) \
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struct mutex mutexname = { __MUTEX_INITIALIZER(mutexname.sema) }
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/**
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* mutex_is_locked - is the mutex locked
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* @lock: the mutex to be queried
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*
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* Returns 1 if the mutex is locked, 0 if unlocked.
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*/
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static inline int mutex_is_locked(struct mutex *lock)
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{
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return sem_getcount(&lock->sema) == 0;
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}
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/*
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* See kernel/mutex.c for detailed documentation of these APIs.
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* Also see Documentation/mutex-design.txt.
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*/
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static inline void mutex_lock(struct mutex *lock)
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{
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down(&lock->sema);
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}
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static inline int mutex_lock_interruptible(struct mutex *lock)
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{
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return down_interruptible(&lock->sema);
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}
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#define mutex_lock_nested(lock, subclass) mutex_lock(lock)
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#define mutex_lock_interruptible_nested(lock, subclass) mutex_lock_interruptible(lock)
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/*
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* NOTE: mutex_trylock() follows the spin_trylock() convention,
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* not the down_trylock() convention!
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*/
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static inline int mutex_trylock(struct mutex *lock)
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{
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return !down_trylock(&lock->sema);
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}
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static inline void mutex_unlock(struct mutex *lock)
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{
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up(&lock->sema);
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}
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#endif
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