From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753430AbaE0SxI (ORCPT ); Tue, 27 May 2014 14:53:08 -0400 Received: from verein.lst.de ([213.95.11.211]:60818 "EHLO newverein.lst.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752654AbaE0SxF (ORCPT ); Tue, 27 May 2014 14:53:05 -0400 Date: Tue, 27 May 2014 20:53:01 +0200 From: Christoph Hellwig To: Jens Axboe Cc: Ming Lei , Linux Kernel Mailing List , stable Subject: Re: [PATCH] block: mq flush: fix race between IPI handler and mq flush worker Message-ID: <20140527185301.GA8466@lst.de> References: <1400511950-18522-1-git-send-email-tom.leiming@gmail.com> <20140519151824.GA21762@lst.de> <20140520152303.GA20352@lst.de> <20140521053634.GA4764@lst.de> <20140527181305.GA7975@lst.de> <5384DB97.70606@kernel.dk> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <5384DB97.70606@kernel.dk> User-Agent: Mutt/1.5.17 (2007-11-01) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, May 27, 2014 at 12:38:15PM -0600, Jens Axboe wrote: > On 2014-05-27 12:13, Christoph Hellwig wrote: >> Here is my counter proposal that requeues via two lists and a work struct >> in the request_queue. I've also tested it with scsi-mq. >> > > I like this, moves the state out of the request. But how about we > consolidate the two requeue requests lists, and just mark the request as > needing head insertion instead? Just add a cmd_flags flag, REQ_REQUEUE_HEAD > or something. That should be doable, just didn't like introducing even more flags.