blk-mq: use blk_mq_start_hw_queues() when running requeue work

When requests are retried due to hw or sw resource shortages,
we often stop the associated hardware queue. So ensure that we
restart the queues when running the requeue work, otherwise the
queue run will be a no-op.

Signed-off-by: Jens Axboe <axboe@fb.com>

block/blk-mq.c

@@ -479,7 +479,11 @@ static void blk_mq_requeue_work(struct work_struct *work)
 		blk_mq_insert_request(rq, false, false, false);
 	}
 
-	blk_mq_run_queues(q, false);
+	/*
+	 * Use the start variant of queue running here, so that running
+	 * the requeue work will kick stopped queues.
+	 */
+	blk_mq_start_hw_queues(q);
 }
 
 void blk_mq_add_to_requeue_list(struct request *rq, bool at_head)