X-Git-Url: http://pilppa.org/gitweb/?a=blobdiff_plain;f=kernel%2Fmutex.c;h=d7fe50cc556fd79624196a175b74996d9b23cf41;hb=a34c2f3a88498257a53630f023afe07d5e6dbdbc;hp=e7cbbb82765b4f66348e927fd2911ac4d9078078;hpb=cece901481bafbf14de8cbd3a89ae869ea881055;p=linux-2.6-omap-h63xx.git diff --git a/kernel/mutex.c b/kernel/mutex.c index e7cbbb82765..d7fe50cc556 100644 --- a/kernel/mutex.c +++ b/kernel/mutex.c @@ -51,6 +51,7 @@ __mutex_init(struct mutex *lock, const char *name, struct lock_class_key *key) EXPORT_SYMBOL(__mutex_init); +#ifndef CONFIG_DEBUG_LOCK_ALLOC /* * We split the mutex lock/unlock logic into separate fastpath and * slowpath functions, to reduce the register pressure on the fastpath. @@ -92,6 +93,7 @@ void inline fastcall __sched mutex_lock(struct mutex *lock) } EXPORT_SYMBOL(mutex_lock); +#endif static void fastcall noinline __sched __mutex_unlock_slowpath(atomic_t *lock_count); @@ -122,7 +124,8 @@ EXPORT_SYMBOL(mutex_unlock); * Lock a mutex (possibly interruptible), slowpath: */ static inline int __sched -__mutex_lock_common(struct mutex *lock, long state, unsigned int subclass) +__mutex_lock_common(struct mutex *lock, long state, unsigned int subclass, + unsigned long ip) { struct task_struct *task = current; struct mutex_waiter waiter; @@ -132,13 +135,19 @@ __mutex_lock_common(struct mutex *lock, long state, unsigned int subclass) spin_lock_mutex(&lock->wait_lock, flags); debug_mutex_lock_common(lock, &waiter); - mutex_acquire(&lock->dep_map, subclass, 0, _RET_IP_); - debug_mutex_add_waiter(lock, &waiter, task->thread_info); + mutex_acquire(&lock->dep_map, subclass, 0, ip); + debug_mutex_add_waiter(lock, &waiter, task_thread_info(task)); /* add waiting tasks to the end of the waitqueue (FIFO): */ list_add_tail(&waiter.list, &lock->wait_list); waiter.task = task; + old_val = atomic_xchg(&lock->count, -1); + if (old_val == 1) + goto done; + + lock_contended(&lock->dep_map, ip); + for (;;) { /* * Lets try to take the lock again - this is needed even if @@ -159,8 +168,8 @@ __mutex_lock_common(struct mutex *lock, long state, unsigned int subclass) */ if (unlikely(state == TASK_INTERRUPTIBLE && signal_pending(task))) { - mutex_remove_waiter(lock, &waiter, task->thread_info); - mutex_release(&lock->dep_map, 1, _RET_IP_); + mutex_remove_waiter(lock, &waiter, task_thread_info(task)); + mutex_release(&lock->dep_map, 1, ip); spin_unlock_mutex(&lock->wait_lock, flags); debug_mutex_free_waiter(&waiter); @@ -174,9 +183,11 @@ __mutex_lock_common(struct mutex *lock, long state, unsigned int subclass) spin_lock_mutex(&lock->wait_lock, flags); } +done: + lock_acquired(&lock->dep_map); /* got the lock - rejoice! */ - mutex_remove_waiter(lock, &waiter, task->thread_info); - debug_mutex_set_owner(lock, task->thread_info); + mutex_remove_waiter(lock, &waiter, task_thread_info(task)); + debug_mutex_set_owner(lock, task_thread_info(task)); /* set it to 0 if there are no waiters left: */ if (likely(list_empty(&lock->wait_list))) @@ -189,20 +200,12 @@ __mutex_lock_common(struct mutex *lock, long state, unsigned int subclass) return 0; } -static void fastcall noinline __sched -__mutex_lock_slowpath(atomic_t *lock_count) -{ - struct mutex *lock = container_of(lock_count, struct mutex, count); - - __mutex_lock_common(lock, TASK_UNINTERRUPTIBLE, 0); -} - #ifdef CONFIG_DEBUG_LOCK_ALLOC void __sched mutex_lock_nested(struct mutex *lock, unsigned int subclass) { might_sleep(); - __mutex_lock_common(lock, TASK_UNINTERRUPTIBLE, subclass); + __mutex_lock_common(lock, TASK_UNINTERRUPTIBLE, subclass, _RET_IP_); } EXPORT_SYMBOL_GPL(mutex_lock_nested); @@ -211,7 +214,7 @@ int __sched mutex_lock_interruptible_nested(struct mutex *lock, unsigned int subclass) { might_sleep(); - return __mutex_lock_common(lock, TASK_INTERRUPTIBLE, subclass); + return __mutex_lock_common(lock, TASK_INTERRUPTIBLE, subclass, _RET_IP_); } EXPORT_SYMBOL_GPL(mutex_lock_interruptible_nested); @@ -263,6 +266,7 @@ __mutex_unlock_slowpath(atomic_t *lock_count) __mutex_unlock_common_slowpath(lock_count, 1); } +#ifndef CONFIG_DEBUG_LOCK_ALLOC /* * Here come the less common (and hence less performance-critical) APIs: * mutex_lock_interruptible() and mutex_trylock(). @@ -290,13 +294,22 @@ int fastcall __sched mutex_lock_interruptible(struct mutex *lock) EXPORT_SYMBOL(mutex_lock_interruptible); +static void fastcall noinline __sched +__mutex_lock_slowpath(atomic_t *lock_count) +{ + struct mutex *lock = container_of(lock_count, struct mutex, count); + + __mutex_lock_common(lock, TASK_UNINTERRUPTIBLE, 0, _RET_IP_); +} + static int fastcall noinline __sched __mutex_lock_interruptible_slowpath(atomic_t *lock_count) { struct mutex *lock = container_of(lock_count, struct mutex, count); - return __mutex_lock_common(lock, TASK_INTERRUPTIBLE, 0); + return __mutex_lock_common(lock, TASK_INTERRUPTIBLE, 0, _RET_IP_); } +#endif /* * Spinlock based trylock, we take the spinlock and check whether we