From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx1.redhat.com ([209.132.183.28]:51612 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932667AbdGLDMX (ORCPT ); Tue, 11 Jul 2017 23:12:23 -0400 Date: Wed, 12 Jul 2017 11:12:13 +0800 From: Ming Lei To: Roger Pau =?iso-8859-1?Q?Monn=E9?= Cc: Jens Axboe , linux-block@vger.kernel.org, Christoph Hellwig , Bart Van Assche , Sagi Grimberg , Konrad Rzeszutek Wilk , Boris Ostrovsky , Juergen Gross , xen-devel@lists.xenproject.org Subject: Re: [PATCH 1/6] xen-blkfront: avoid to use start/stop queue Message-ID: <20170712031212.GF13036@ming.t460p> References: <20170711182103.11461-1-ming.lei@redhat.com> <20170711182103.11461-2-ming.lei@redhat.com> <20170711212444.ttmkvlxexuduzfcj@MacBook-Pro-de-Roger.local> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 In-Reply-To: <20170711212444.ttmkvlxexuduzfcj@MacBook-Pro-de-Roger.local> Sender: linux-block-owner@vger.kernel.org List-Id: linux-block@vger.kernel.org On Tue, Jul 11, 2017 at 11:24:44PM +0200, Roger Pau Monn� wrote: > On Wed, Jul 12, 2017 at 02:20:58AM +0800, Ming Lei wrote: > > This interfaces will be removed soon, so use quiesce and > > unquiesce instead, which should be more safe. > > > > The only one usage will be removed in the following > > congestion control patches. > > Would it be better to simply fix blk_mq_{start/stop}_stopped_hw_queues > rather than introducing a new interface? No, we do not want to expose start/stop state to drivers any more, which has caused enough trouble already, so these APIs need to be removed, and quiesce/unquiesce is preferred way for this purpose, as you can see the work done by Sagi Grimberg: http://marc.info/?t=149927415900006&r=1&w=2 Thanks, Ming