diff options
Diffstat (limited to '')
| -rw-r--r-- | kernel/mutex.c | 95 |
1 files changed, 59 insertions, 36 deletions
diff --git a/kernel/mutex.c b/kernel/mutex.c index 5449b210d9ed..8c71cf72a497 100644 --- a/kernel/mutex.c +++ b/kernel/mutex.c @@ -17,6 +17,7 @@ #include <linux/module.h> #include <linux/spinlock.h> #include <linux/interrupt.h> +#include <linux/debug_locks.h> /* * In the DEBUG case we are using the "NULL fastpath" for mutexes, @@ -38,13 +39,14 @@ * * It is not allowed to initialize an already locked mutex. */ -void fastcall __mutex_init(struct mutex *lock, const char *name) +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); - debug_mutex_init(lock, name); + debug_mutex_init(lock, name, key); } EXPORT_SYMBOL(__mutex_init); @@ -56,7 +58,7 @@ EXPORT_SYMBOL(__mutex_init); * branch is predicted by the CPU as default-untaken. */ static void fastcall noinline __sched -__mutex_lock_slowpath(atomic_t *lock_count __IP_DECL__); +__mutex_lock_slowpath(atomic_t *lock_count); /*** * mutex_lock - acquire the mutex @@ -79,7 +81,7 @@ __mutex_lock_slowpath(atomic_t *lock_count __IP_DECL__); * * This function is similar to (but not equivalent to) down(). */ -void fastcall __sched mutex_lock(struct mutex *lock) +void inline fastcall __sched mutex_lock(struct mutex *lock) { might_sleep(); /* @@ -92,7 +94,7 @@ void fastcall __sched mutex_lock(struct mutex *lock) EXPORT_SYMBOL(mutex_lock); static void fastcall noinline __sched -__mutex_unlock_slowpath(atomic_t *lock_count __IP_DECL__); +__mutex_unlock_slowpath(atomic_t *lock_count); /*** * mutex_unlock - release the mutex @@ -120,17 +122,18 @@ EXPORT_SYMBOL(mutex_unlock); * Lock a mutex (possibly interruptible), slowpath: */ static inline int __sched -__mutex_lock_common(struct mutex *lock, long state __IP_DECL__) +__mutex_lock_common(struct mutex *lock, long state, unsigned int subclass) { struct task_struct *task = current; struct mutex_waiter waiter; unsigned int old_val; + unsigned long flags; - debug_mutex_init_waiter(&waiter); + spin_lock_mutex(&lock->wait_lock, flags); - spin_lock_mutex(&lock->wait_lock); - - debug_mutex_add_waiter(lock, &waiter, task->thread_info, ip); + debug_mutex_lock_common(lock, &waiter); + mutex_acquire(&lock->dep_map, subclass, 0, _RET_IP_); + debug_mutex_add_waiter(lock, &waiter, task->thread_info); /* add waiting tasks to the end of the waitqueue (FIFO): */ list_add_tail(&waiter.list, &lock->wait_list); @@ -157,7 +160,8 @@ __mutex_lock_common(struct mutex *lock, long state __IP_DECL__) if (unlikely(state == TASK_INTERRUPTIBLE && signal_pending(task))) { mutex_remove_waiter(lock, &waiter, task->thread_info); - spin_unlock_mutex(&lock->wait_lock); + mutex_release(&lock->dep_map, 1, _RET_IP_); + spin_unlock_mutex(&lock->wait_lock, flags); debug_mutex_free_waiter(&waiter); return -EINTR; @@ -165,48 +169,57 @@ __mutex_lock_common(struct mutex *lock, long state __IP_DECL__) __set_task_state(task, state); /* didnt get the lock, go to sleep: */ - spin_unlock_mutex(&lock->wait_lock); + spin_unlock_mutex(&lock->wait_lock, flags); schedule(); - spin_lock_mutex(&lock->wait_lock); + spin_lock_mutex(&lock->wait_lock, flags); } /* got the lock - rejoice! */ mutex_remove_waiter(lock, &waiter, task->thread_info); - debug_mutex_set_owner(lock, task->thread_info __IP__); + debug_mutex_set_owner(lock, task->thread_info); /* set it to 0 if there are no waiters left: */ if (likely(list_empty(&lock->wait_list))) atomic_set(&lock->count, 0); - spin_unlock_mutex(&lock->wait_lock); + spin_unlock_mutex(&lock->wait_lock, flags); debug_mutex_free_waiter(&waiter); - DEBUG_WARN_ON(list_empty(&lock->held_list)); - DEBUG_WARN_ON(lock->owner != task->thread_info); - return 0; } static void fastcall noinline __sched -__mutex_lock_slowpath(atomic_t *lock_count __IP_DECL__) +__mutex_lock_slowpath(atomic_t *lock_count) { struct mutex *lock = container_of(lock_count, struct mutex, count); - __mutex_lock_common(lock, TASK_UNINTERRUPTIBLE __IP__); + __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); } +EXPORT_SYMBOL_GPL(mutex_lock_nested); +#endif + /* * Release the lock, slowpath: */ -static fastcall noinline void -__mutex_unlock_slowpath(atomic_t *lock_count __IP_DECL__) +static fastcall inline void +__mutex_unlock_common_slowpath(atomic_t *lock_count, int nested) { struct mutex *lock = container_of(lock_count, struct mutex, count); + unsigned long flags; - DEBUG_WARN_ON(lock->owner != current_thread_info()); - - spin_lock_mutex(&lock->wait_lock); + spin_lock_mutex(&lock->wait_lock, flags); + mutex_release(&lock->dep_map, nested, _RET_IP_); + debug_mutex_unlock(lock); /* * some architectures leave the lock unlocked in the fastpath failure @@ -216,8 +229,6 @@ __mutex_unlock_slowpath(atomic_t *lock_count __IP_DECL__) if (__mutex_slowpath_needs_to_unlock()) atomic_set(&lock->count, 1); - debug_mutex_unlock(lock); - if (!list_empty(&lock->wait_list)) { /* get the first entry from the wait-list: */ struct mutex_waiter *waiter = @@ -231,7 +242,16 @@ __mutex_unlock_slowpath(atomic_t *lock_count __IP_DECL__) debug_mutex_clear_owner(lock); - spin_unlock_mutex(&lock->wait_lock); + spin_unlock_mutex(&lock->wait_lock, flags); +} + +/* + * Release the lock, slowpath: + */ +static fastcall noinline void +__mutex_unlock_slowpath(atomic_t *lock_count) +{ + __mutex_unlock_common_slowpath(lock_count, 1); } /* @@ -239,7 +259,7 @@ __mutex_unlock_slowpath(atomic_t *lock_count __IP_DECL__) * mutex_lock_interruptible() and mutex_trylock(). */ static int fastcall noinline __sched -__mutex_lock_interruptible_slowpath(atomic_t *lock_count __IP_DECL__); +__mutex_lock_interruptible_slowpath(atomic_t *lock_count); /*** * mutex_lock_interruptible - acquire the mutex, interruptable @@ -262,11 +282,11 @@ int fastcall __sched mutex_lock_interruptible(struct mutex *lock) EXPORT_SYMBOL(mutex_lock_interruptible); static int fastcall noinline __sched -__mutex_lock_interruptible_slowpath(atomic_t *lock_count __IP_DECL__) +__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 __IP__); + return __mutex_lock_common(lock, TASK_INTERRUPTIBLE, 0); } /* @@ -276,18 +296,21 @@ __mutex_lock_interruptible_slowpath(atomic_t *lock_count __IP_DECL__) static inline int __mutex_trylock_slowpath(atomic_t *lock_count) { struct mutex *lock = container_of(lock_count, struct mutex, count); + unsigned long flags; int prev; - spin_lock_mutex(&lock->wait_lock); + spin_lock_mutex(&lock->wait_lock, flags); prev = atomic_xchg(&lock->count, -1); - if (likely(prev == 1)) - debug_mutex_set_owner(lock, current_thread_info() __RET_IP__); + if (likely(prev == 1)) { + debug_mutex_set_owner(lock, current_thread_info()); + mutex_acquire(&lock->dep_map, 0, 1, _RET_IP_); + } /* Set it back to 0 if there are no waiters: */ if (likely(list_empty(&lock->wait_list))) atomic_set(&lock->count, 0); - spin_unlock_mutex(&lock->wait_lock); + spin_unlock_mutex(&lock->wait_lock, flags); return prev == 1; } @@ -306,7 +329,7 @@ static inline int __mutex_trylock_slowpath(atomic_t *lock_count) * This function must not be used in interrupt context. The * mutex must be released by the same task that acquired it. */ -int fastcall mutex_trylock(struct mutex *lock) +int fastcall __sched mutex_trylock(struct mutex *lock) { return __mutex_fastpath_trylock(&lock->count, __mutex_trylock_slowpath); |