From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752865AbbJNDby (ORCPT ); Tue, 13 Oct 2015 23:31:54 -0400 Received: from mail-pa0-f43.google.com ([209.85.220.43]:36623 "EHLO mail-pa0-f43.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751947AbbJNDbG (ORCPT ); Tue, 13 Oct 2015 23:31:06 -0400 From: Ming Lei To: Jens Axboe , linux-kernel@vger.kernel.org Cc: Ming Lin , Kent Overstreet , Christoph Hellwig , Ming Lei Subject: [PATCH 3/4] blk-mq: check bio_mergeable() early before merging Date: Wed, 14 Oct 2015 11:30:47 +0800 Message-Id: <1444793448-9994-4-git-send-email-ming.lei@canonical.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1444793448-9994-1-git-send-email-ming.lei@canonical.com> References: <1444793448-9994-1-git-send-email-ming.lei@canonical.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org It isn't necessary to try to merge the bio which is marked as NOMERGE. Signed-off-by: Ming Lei --- block/blk-mq.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/block/blk-mq.c b/block/blk-mq.c index 546b3b8..deb5f4c 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -671,6 +671,9 @@ static bool blk_mq_attempt_merge(struct request_queue *q, struct request *rq; int checked = 8; + if (!bio_mergeable(bio)) + return false; + list_for_each_entry_reverse(rq, &ctx->rq_list, queuelist) { int el_ret; @@ -1140,7 +1143,7 @@ static inline bool blk_mq_merge_queue_io(struct blk_mq_hw_ctx *hctx, struct blk_mq_ctx *ctx, struct request *rq, struct bio *bio) { - if (!hctx_allow_merges(hctx)) { + if (!hctx_allow_merges(hctx) || !bio_mergeable(bio)) { blk_mq_bio_to_request(rq, bio); spin_lock(&ctx->lock); insert_rq: -- 1.9.1