blk-mq: don't call io sched's .requeue_request when requeueing rq to ->dispatch
__blk_mq_requeue_request() covers two cases:
- one is that the requeued request is added to hctx->dispatch, such as
blk_mq_dispatch_rq_list()
- another case is that the request is requeued to io scheduler, such as
blk_mq_requeue_request().
We should call io sched's .requeue_request callback only for the 2nd
case.
Cc: Paolo Valente <paolo.valente@linaro.org>
Cc: Omar Sandoval <osandov@fb.com>
Fixes: bd166ef183c2 ("blk-mq-sched: add framework for MQ capable IO schedulers")
Cc: stable@vger.kernel.org
Reviewed-by: Bart Van Assche <bart.vanassche@wdc.com>
Acked-by: Paolo Valente <paolo.valente@linaro.org>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
diff --git a/block/blk-mq.c b/block/blk-mq.c
index 3574927..16e83e6 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -712,7 +712,6 @@
trace_block_rq_requeue(q, rq);
wbt_requeue(q->rq_wb, &rq->issue_stat);
- blk_mq_sched_requeue_request(rq);
if (blk_mq_rq_state(rq) != MQ_RQ_IDLE) {
blk_mq_rq_update_state(rq, MQ_RQ_IDLE);
@@ -725,6 +724,9 @@
{
__blk_mq_requeue_request(rq);
+ /* this request will be re-inserted to io scheduler queue */
+ blk_mq_sched_requeue_request(rq);
+
BUG_ON(blk_queued_rq(rq));
blk_mq_add_to_requeue_list(rq, true, kick_requeue_list);
}