block: call rq_qos_exit() after queue is frozen

rq_qos_exit() removes the current q->rq_qos, this action has to be
done after queue is frozen, otherwise the IO queue path may never
be waken up, then IO hang is caused.

So fixes this issue by moving rq_qos_exit() after queue is frozen.

Cc: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Ming Lei 2018-10-24 21:18:09 +08:00 committed by Jens Axboe
parent 698b53b311
commit c57cdf7a9e
2 changed files with 3 additions and 2 deletions

View File

@ -785,6 +785,9 @@ void blk_cleanup_queue(struct request_queue *q)
* prevent that q->request_fn() gets invoked after draining finished.
*/
blk_freeze_queue(q);
rq_qos_exit(q);
spin_lock_irq(lock);
queue_flag_set(QUEUE_FLAG_DEAD, q);
spin_unlock_irq(lock);

View File

@ -1007,8 +1007,6 @@ void blk_unregister_queue(struct gendisk *disk)
kobject_del(&q->kobj);
blk_trace_remove_sysfs(disk_to_dev(disk));
rq_qos_exit(q);
mutex_lock(&q->sysfs_lock);
if (q->request_fn || (q->mq_ops && q->elevator))
elv_unregister_queue(q);