diff options
Diffstat (limited to 'kernel/locking/rwsem-xadd.c')
| -rw-r--r-- | kernel/locking/rwsem-xadd.c | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/kernel/locking/rwsem-xadd.c b/kernel/locking/rwsem-xadd.c index 0b1f77957240..385ebcfc31a6 100644 --- a/kernel/locking/rwsem-xadd.c +++ b/kernel/locking/rwsem-xadd.c @@ -454,6 +454,8 @@ __rwsem_down_read_failed_common(struct rw_semaphore *sem, int state) * been set in the count. */ if (atomic_long_read(&sem->count) >= 0) { + /* Provide lock ACQUIRE */ + smp_acquire__after_ctrl_dep(); raw_spin_unlock_irq(&sem->wait_lock); rwsem_set_reader_owned(sem); lockevent_inc(rwsem_rlock_fast); @@ -483,8 +485,10 @@ __rwsem_down_read_failed_common(struct rw_semaphore *sem, int state) /* wait to be given the lock */ while (true) { set_current_state(state); - if (!waiter.task) + if (!smp_load_acquire(&waiter.task)) { + /* Orders against rwsem_mark_wake()'s smp_store_release() */ break; + } if (signal_pending_state(state, current)) { raw_spin_lock_irq(&sem->wait_lock); if (waiter.task) |