Patch "blk-mq: don't call io sched's .requeue_request when requeueing rq to ->dispatch" has been added to the 4.15-stable tree

This is a note to let you know that I've just added the patch titled

    blk-mq: don't call io sched's .requeue_request when requeueing rq to ->dispatch

to the 4.15-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
blk-mq-don-t-call-io-sched-s-.requeue_request-when-requeueing-rq-to-dispatch.patch
and it can be found in the queue-4.15 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Ming Lei <[email protected]>
Date: Fri, 23 Feb 2018 23:36:56 +0800
Subject: blk-mq: don't call io sched's .requeue_request when requeueing rq to ->dispatch

From: Ming Lei <[email protected]>

commit 105976f517791aed3b11f8f53b308a2069d42055 upstream.

__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.

---
 block/blk-mq.c |    4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

@@ -655,7 +655,6 @@ static void __blk_mq_requeue_request(str
 
 	trace_block_rq_requeue(q, rq);
 	wbt_requeue(q->rq_wb, &rq->issue_stat);
-	blk_mq_sched_requeue_request(rq);
 
 	if (test_and_clear_bit(REQ_ATOM_STARTED, &rq->atomic_flags)) {
 		if (q->dma_drain_size && blk_rq_bytes(rq))

@@ -667,6 +666,9 @@ void blk_mq_requeue_request(struct reque
 {
 	__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);
 }

Patches currently in stable-queue which might be from [email protected] are

queue-4.15/block-pass-inclusive-lend-parameter-to-truncate_inode_pages_range.patch queue-4.15/blk-mq-don-t-call-io-sched-s-.requeue_request-when-requeueing-rq-to-dispatch.patch queue-4.15/block-kyber-fix-domain-token-leak-during-requeue.patch