diff options
Diffstat (limited to 'kernel/locking/rt.c')
-rw-r--r-- | kernel/locking/rt.c | 60 |
1 files changed, 22 insertions, 38 deletions
diff --git a/kernel/locking/rt.c b/kernel/locking/rt.c index 5d177272ffb4..055a3df13c2a 100644 --- a/kernel/locking/rt.c +++ b/kernel/locking/rt.c @@ -180,12 +180,14 @@ EXPORT_SYMBOL(_mutex_unlock); */ int __lockfunc rt_write_trylock(rwlock_t *rwlock) { - int ret = rt_mutex_trylock(&rwlock->lock); + int ret; - if (ret) { + migrate_disable(); + ret = rt_mutex_trylock(&rwlock->lock); + if (ret) rwlock_acquire(&rwlock->dep_map, 0, 1, _RET_IP_); - migrate_disable(); - } + else + migrate_enable(); return ret; } @@ -212,11 +214,13 @@ int __lockfunc rt_read_trylock(rwlock_t *rwlock) * write locked. */ if (rt_mutex_owner(lock) != current) { + migrate_disable(); ret = rt_mutex_trylock(lock); - if (ret) { + if (ret) rwlock_acquire(&rwlock->dep_map, 0, 1, _RET_IP_); - migrate_disable(); - } + else + migrate_enable(); + } else if (!rwlock->read_depth) { ret = 0; } @@ -240,13 +244,14 @@ void __lockfunc rt_read_lock(rwlock_t *rwlock) { struct rt_mutex *lock = &rwlock->lock; + /* * recursive read locks succeed when current owns the lock */ if (rt_mutex_owner(lock) != current) { - rwlock_acquire(&rwlock->dep_map, 0, 0, _RET_IP_); - __rt_spin_lock(lock); migrate_disable(); + rwlock_acquire_read(&rwlock->dep_map, 0, 0, _RET_IP_); + __rt_spin_lock(lock); } rwlock->read_depth++; } @@ -316,10 +321,8 @@ EXPORT_SYMBOL(rt_up_write); void rt_up_read(struct rw_semaphore *rwsem) { - if (--rwsem->read_depth == 0) { - rwsem_release(&rwsem->dep_map, 1, _RET_IP_); - rt_mutex_unlock(&rwsem->lock); - } + rwsem_release(&rwsem->dep_map, 1, _RET_IP_); + rt_mutex_unlock(&rwsem->lock); } EXPORT_SYMBOL(rt_up_read); @@ -330,7 +333,6 @@ EXPORT_SYMBOL(rt_up_read); void rt_downgrade_write(struct rw_semaphore *rwsem) { BUG_ON(rt_mutex_owner(&rwsem->lock) != current); - rwsem->read_depth = 1; } EXPORT_SYMBOL(rt_downgrade_write); @@ -367,37 +369,20 @@ void rt_down_write_nested_lock(struct rw_semaphore *rwsem, int rt_down_read_trylock(struct rw_semaphore *rwsem) { - struct rt_mutex *lock = &rwsem->lock; - int ret = 1; - - /* - * recursive read locks succeed when current owns the rwsem, - * but not when read_depth == 0 which means that the rwsem is - * write locked. - */ - if (rt_mutex_owner(lock) != current) { - ret = rt_mutex_trylock(&rwsem->lock); - if (ret) - rwsem_acquire(&rwsem->dep_map, 0, 1, _RET_IP_); - } else if (!rwsem->read_depth) { - ret = 0; - } + int ret; + ret = rt_mutex_trylock(&rwsem->lock); if (ret) - rwsem->read_depth++; + rwsem_acquire(&rwsem->dep_map, 0, 1, _RET_IP_); + return ret; } EXPORT_SYMBOL(rt_down_read_trylock); static void __rt_down_read(struct rw_semaphore *rwsem, int subclass) { - struct rt_mutex *lock = &rwsem->lock; - - if (rt_mutex_owner(lock) != current) { - rwsem_acquire(&rwsem->dep_map, subclass, 0, _RET_IP_); - rt_mutex_lock(&rwsem->lock); - } - rwsem->read_depth++; + rwsem_acquire(&rwsem->dep_map, subclass, 0, _RET_IP_); + rt_mutex_lock(&rwsem->lock); } void rt_down_read(struct rw_semaphore *rwsem) @@ -422,7 +407,6 @@ void __rt_rwsem_init(struct rw_semaphore *rwsem, const char *name, debug_check_no_locks_freed((void *)rwsem, sizeof(*rwsem)); lockdep_init_map(&rwsem->dep_map, name, key, 0); #endif - rwsem->read_depth = 0; rwsem->lock.save_state = 0; } EXPORT_SYMBOL(__rt_rwsem_init); |