Commit f168420c authored by Liu Song's avatar Liu Song Committed by Jens Axboe
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blk-mq: don't redirect completion for hctx withs only one ctx mapping 



High-performance NVMe devices usually support a large hw queues, which
ensures a 1:1 mapping of hctx and ctx. In this case there will be no
remote request, so we don't need to care about it.

Signed-off-by: default avatarLiu Song <liusong@linux.alibaba.com>
Link: https://lore.kernel.org/r/1663731123-81536-1-git-send-email-liusong@linux.alibaba.com


Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent 81c7a63a

block/blk-mq.c

+5 −3
Original line number Diff line number Diff line
@@ -1093,10 +1093,12 @@ bool blk_mq_complete_request_remote(struct request *rq) 
	WRITE_ONCE(rq->state, MQ_RQ_COMPLETE);



	/*

	 * For a polled request, always complete locally, it's pointless

	 * to redirect the completion.

	 * For request which hctx has only one ctx mapping,

	 * or a polled request, always complete locally,

	 * it's pointless to redirect the completion.

	 */

	if (rq->cmd_flags & REQ_POLLED)

	if (rq->mq_hctx->nr_ctx == 1 ||

		rq->cmd_flags & REQ_POLLED)

		return false;



	if (blk_mq_complete_need_ipi(rq)) {