nbd: quiesce request queues to make sure no submissions are inflight

Unlike blk_mq_stop_hw_queues, blk_mq_quiesce_queue respects the
submission path rcu grace. quiesce the queue before iterating
on live tags.

Reviewed-by: Ming Lei <ming.lei@redhat.com>
Acked-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
This commit is contained in:
Sagi Grimberg 2017-07-04 09:57:09 +03:00
parent 8d7b8fafad
commit b52c2e9254

View file

@ -661,9 +661,9 @@ static void nbd_clear_req(struct request *req, void *data, bool reserved)
static void nbd_clear_que(struct nbd_device *nbd)
{
blk_mq_stop_hw_queues(nbd->disk->queue);
blk_mq_quiesce_queue(nbd->disk->queue);
blk_mq_tagset_busy_iter(&nbd->tag_set, nbd_clear_req, NULL);
blk_mq_start_hw_queues(nbd->disk->queue);
blk_mq_unquiesce_queue(nbd->disk->queue);
dev_dbg(disk_to_dev(nbd->disk), "queue cleared\n");
}