From mboxrd@z Thu Jan 1 00:00:00 1970 From: "NeilBrown" Subject: Re: Re: Write barriers on MD RAID1 Date: Wed, 24 Jun 2009 17:34:50 +1000 (EST) Message-ID: References: <4A188CAD.1080009@googlemail.com> <0fa4b1e19d3edb12931e0d641ce2c7d7.squirrel@neil.brown.name> <4A3E3C49.7010907@googlemail.com> <19009.41191.662901.179565@notabene.brown> <20090624070917.GB27500@agk-dp.fab.redhat.com> Reply-To: device-mapper development Mime-Version: 1.0 Content-Type: text/plain;charset=iso-8859-1 Content-Transfer-Encoding: quoted-printable Return-path: In-Reply-To: <20090624070917.GB27500@agk-dp.fab.redhat.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: dm-devel-bounces@redhat.com Errors-To: dm-devel-bounces@redhat.com To: Neil Brown , device-mapper development , Ken Milmore , linux-raid@vger.kernel.org, linux-kernel@vger.kernel.org List-Id: linux-raid.ids On Wed, June 24, 2009 5:09 pm, Alasdair G Kergon wrote: > On Wed, Jun 24, 2009 at 01:43:35PM +1000, Neil Brown wrote: >> Since this test was added, barriers have not worked on md, and (I >> think) dm and similar devices that don't use __make_request and so >> don't bother to set next_ordered. > > In dm, we added this: > > + blk_queue_ordered(md->queue, QUEUE_ORDERED_DRAIN, NULL); > I obviously didn't grep for the right thing. This will obviously work, but I can't help thinking it is in the wrong place. I don't even have a queue in md/raid1, so making a statement about how it is ordered just doesn't make sense. Jens? NeilBrown