From 2299722c4b117af867425d097e470c8566e0c82e Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Wed, 22 Mar 2017 15:01:52 -0400 Subject: [PATCH] blk-mq: split the plug and sync cases in blk_mq_make_request Now that we have a nice direct issue heper this helps simplifying the code a bit, and also gets rid of the old_rq variable. Signed-off-by: Christoph Hellwig Signed-off-by: Jens Axboe --- block/blk-mq.c | 36 ++++++++++++++++++------------------ 1 file changed, 18 insertions(+), 18 deletions(-) diff --git a/block/blk-mq.c b/block/blk-mq.c index e82e1a9c7d5e..a9d2e02a8e02 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -1569,32 +1569,32 @@ static blk_qc_t blk_mq_make_request(struct request_queue *q, struct bio *bio) list_add_tail(&rq->queuelist, &plug->mq_list); goto done; - } else if (((plug && !blk_queue_nomerges(q)) || is_sync)) { - struct request *old_rq = NULL; - + } else if (plug && !blk_queue_nomerges(q)) { blk_mq_bio_to_request(rq, bio); /* * We do limited plugging. If the bio can be merged, do that. * Otherwise the existing request in the plug list will be * issued. So the plug list will have one request at most + * The plug list might get flushed before this. If that happens, + * the plug list is empty, and same_queue_rq is invalid. */ - if (plug) { - /* - * The plug list might get flushed before this. If that - * happens, same_queue_rq is invalid and plug list is - * empty - */ - if (same_queue_rq && !list_empty(&plug->mq_list)) { - old_rq = same_queue_rq; - list_del_init(&old_rq->queuelist); - } - list_add_tail(&rq->queuelist, &plug->mq_list); - } else /* is_sync */ - old_rq = rq; + if (list_empty(&plug->mq_list)) + same_queue_rq = NULL; + if (same_queue_rq) + list_del_init(&same_queue_rq->queuelist); + list_add_tail(&rq->queuelist, &plug->mq_list); + blk_mq_put_ctx(data.ctx); - if (old_rq) - blk_mq_try_issue_directly(data.hctx, old_rq, &cookie); + if (same_queue_rq) + blk_mq_try_issue_directly(data.hctx, same_queue_rq, + &cookie); + goto done; + } else if (is_sync) { + blk_mq_bio_to_request(rq, bio); + + blk_mq_put_ctx(data.ctx); + blk_mq_try_issue_directly(data.hctx, rq, &cookie); goto done; }