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Linux Kernel 互斥量初始化

void __mutex_init(struct mutex *lock, const char *name, struct lock_class_key *key)
{
	atomic_set(&lock->count, 1);
	spin_lock_init(&lock->wait_lock);
	INIT_LIST_HEAD(&lock->wait_list);
	mutex_clear_owner(lock);
#ifdef CONFIG_MUTEX_SPIN_ON_OWNER
	osq_lock_init(&lock->osq);
#endif

	debug_mutex_init(lock, name, key);
}
EXPORT_SYMBOL(__mutex_init);
      
#define __MUTEX_INITIALIZER(lockname) \
		{ .count = ATOMIC_INIT(1) \
		, .wait_lock = __SPIN_LOCK_UNLOCKED(lockname.wait_lock) \
		, .wait_list = LIST_HEAD_INIT(lockname.wait_list) \
		__DEBUG_MUTEX_INITIALIZER(lockname) \
		__DEP_MAP_MUTEX_INITIALIZER(lockname) }


#define DEFINE_MUTEX(mutexname) \
	struct mutex mutexname = __MUTEX_INITIALIZER(mutexname)
      
/**
 * mutex_init - initialize the mutex
 * @mutex: the mutex to be initialized
 *
 * Initialize the mutex to unlocked state.
 *
 * It is not allowed to initialize an already locked mutex.
 */
# define mutex_init(mutex) \
do {							\
	static struct lock_class_key __key;		\
							\
	__mutex_init((mutex), #mutex, &__key);		\
} while (0)