diff options
Diffstat (limited to 'block/blk-ioc.c')
| -rw-r--r-- | block/blk-ioc.c | 16 |
1 files changed, 6 insertions, 10 deletions
diff --git a/block/blk-ioc.c b/block/blk-ioc.c index ce82770c72ab..9fda3906e5f5 100644 --- a/block/blk-ioc.c +++ b/block/blk-ioc.c @@ -308,24 +308,23 @@ int __copy_io(unsigned long clone_flags, struct task_struct *tsk) #ifdef CONFIG_BLK_ICQ /** - * ioc_lookup_icq - lookup io_cq from ioc + * ioc_lookup_icq - lookup io_cq from ioc in io issue path * @q: the associated request_queue * * Look up io_cq associated with @ioc - @q pair from @ioc. Must be called - * with @q->queue_lock held. + * from io issue path, either return NULL if current issue io to @q for the + * first time, or return a valid icq. */ struct io_cq *ioc_lookup_icq(struct request_queue *q) { struct io_context *ioc = current->io_context; struct io_cq *icq; - lockdep_assert_held(&q->queue_lock); - /* * icq's are indexed from @ioc using radix tree and hint pointer, - * both of which are protected with RCU. All removals are done - * holding both q and ioc locks, and we're holding q lock - if we - * find a icq which points to us, it's guaranteed to be valid. + * both of which are protected with RCU, io issue path ensures that + * both request_queue and current task are valid, the found icq + * is guaranteed to be valid until the io is done. */ rcu_read_lock(); icq = rcu_dereference(ioc->icq_hint); @@ -419,10 +418,7 @@ struct io_cq *ioc_find_get_icq(struct request_queue *q) task_unlock(current); } else { get_io_context(ioc); - - spin_lock_irq(&q->queue_lock); icq = ioc_lookup_icq(q); - spin_unlock_irq(&q->queue_lock); } if (!icq) { |