From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx1.redhat.com ([209.132.183.28]:56106 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751407AbdINQmZ (ORCPT ); Thu, 14 Sep 2017 12:42:25 -0400 From: Ming Lei To: Jens Axboe , linux-block@vger.kernel.org Cc: Omar Sandoval , Ming Lei Subject: [PATCH 0/6] blk-mq: don't allocate driver tag beforehand for flush rq Date: Fri, 15 Sep 2017 00:42:07 +0800 Message-Id: <20170914164213.17859-1-ming.lei@redhat.com> Sender: linux-block-owner@vger.kernel.org List-Id: linux-block@vger.kernel.org Hi, This patchset avoids to allocate driver tag beforehand for flush rq in case of I/O scheduler, then flush rq isn't treated specially wrt. get/put driver tag, code gets cleanup much, such as, reorder_tags_to_front() is removed, and we needn't to worry about request order in dispatch list for avoiding I/O deadlock. 'dbench -t 30 -s -F 64' has been run on different devices(shared tag, multi-queue, singele queue, ...), and no issues are observed, even very low queue depth(1) test are run, debench still works well. Any comments are welcome! Thanks, Ming Ming Lei (6): blk-flush: don't run queue for requests of bypassing flush block: pass 'run_queue' to blk_mq_request_bypass_insert blk-flush: use blk_mq_request_bypass_insert() blk-mq: decide how to handle flush rq via RQF_FLUSH_SEQ blk-mq: move __blk_mq_put_driver_tag() into blk-mq.h blk-mq: don't allocate driver tag beforehand for flush rq block/blk-core.c | 2 +- block/blk-flush.c | 43 +++++++++++++++++++++++++++++------ block/blk-mq-sched.c | 64 ++++++++++++++-------------------------------------- block/blk-mq.c | 55 ++++++-------------------------------------- block/blk-mq.h | 15 +++++++++++- 5 files changed, 75 insertions(+), 104 deletions(-) -- 2.9.5