From f168420c62e7a106961f2489a89f6ade84fe3f27 Mon Sep 17 00:00:00 2001 From: Liu Song Date: Wed, 21 Sep 2022 11:32:03 +0800 Subject: 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: Liu Song Link: https://lore.kernel.org/r/1663731123-81536-1-git-send-email-liusong@linux.alibaba.com Signed-off-by: Jens Axboe --- block/blk-mq.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) (limited to 'block/blk-mq.c') diff --git a/block/blk-mq.c b/block/blk-mq.c index 29bb48de5bda..496085132899 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -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)) { -- cgit 1.4.1