# include <asm/mutex.h>
#endif
-/***
- * mutex_init - initialize the mutex
- * @lock: the mutex to be initialized
- * @key: the lock_class_key for the class; used by mutex lock debugging
- *
- * Initialize the mutex to unlocked state.
- *
- * It is not allowed to initialize an already locked mutex.
- */
void
__mutex_init(struct mutex *lock, const char *name, struct lock_class_key *key)
{
static __used noinline void __sched
__mutex_lock_slowpath(atomic_t *lock_count);
-/***
+/**
* mutex_lock - acquire the mutex
* @lock: the mutex to be acquired
*
static __used noinline void __sched __mutex_unlock_slowpath(atomic_t *lock_count);
-/***
+/**
* mutex_unlock - release the mutex
* @lock: the mutex to be released
*
preempt_disable();
mutex_acquire(&lock->dep_map, subclass, 0, ip);
-#if defined(CONFIG_SMP) && !defined(CONFIG_DEBUG_MUTEXES) && \
- !defined(CONFIG_HAVE_DEFAULT_NO_SPIN_MUTEXES)
+
+#ifdef CONFIG_MUTEX_SPIN_ON_OWNER
/*
* Optimistic spinning.
*
for (;;) {
struct thread_info *owner;
+ /*
+ * If we own the BKL, then don't spin. The owner of
+ * the mutex might be waiting on us to release the BKL.
+ */
+ if (unlikely(current->lock_depth >= 0))
+ break;
+
/*
* If there's an owner, wait for it to either
* release the lock or go to sleep.
* memory barriers as we'll eventually observe the right
* values at the cost of a few extra spins.
*/
- cpu_relax();
+ arch_mutex_cpu_relax();
}
#endif
spin_lock_mutex(&lock->wait_lock, flags);
}
__set_task_state(task, state);
- /* didnt get the lock, go to sleep: */
+ /* didn't get the lock, go to sleep: */
spin_unlock_mutex(&lock->wait_lock, flags);
- __schedule();
+ preempt_enable_no_resched();
+ schedule();
+ preempt_disable();
spin_lock_mutex(&lock->wait_lock, flags);
}
static noinline int __sched
__mutex_lock_interruptible_slowpath(atomic_t *lock_count);
-/***
- * mutex_lock_interruptible - acquire the mutex, interruptable
+/**
+ * mutex_lock_interruptible - acquire the mutex, interruptible
* @lock: the mutex to be acquired
*
* Lock the mutex like mutex_lock(), and return 0 if the mutex has
return prev == 1;
}
-/***
- * mutex_trylock - try acquire the mutex, without waiting
+/**
+ * mutex_trylock - try to acquire the mutex, without waiting
* @lock: the mutex to be acquired
*
* Try to acquire the mutex atomically. Returns 1 if the mutex
* has been acquired successfully, and 0 on contention.
*
* NOTE: this function follows the spin_trylock() convention, so
- * it is negated to the down_trylock() return values! Be careful
+ * it is negated from the down_trylock() return values! Be careful
* about this when converting semaphore users to mutexes.
*
* This function must not be used in interrupt context. The