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From: "NeilBrown" <neilb@suse.de>
To: Neil Brown <neilb@suse.de>,
	device-mapper development <dm-devel@redhat.com>,
	Ken Milmore <ken.milmore@googlemail.com>,
	linux-raid@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: Re: Write barriers on MD RAID1
Date: Wed, 24 Jun 2009 17:34:50 +1000 (EST)	[thread overview]
Message-ID: <ee1590411620eede90e75c14fde50244.squirrel@neil.brown.name> (raw)
In-Reply-To: <20090624070917.GB27500@agk-dp.fab.redhat.com>

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

  reply	other threads:[~2009-06-24  7:34 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <4A188CAD.1080009@googlemail.com>
     [not found] ` <0fa4b1e19d3edb12931e0d641ce2c7d7.squirrel@neil.brown.name>
     [not found]   ` <4A3E3C49.7010907@googlemail.com>
2009-06-24  3:43     ` Write barriers on MD RAID1 Neil Brown
2009-06-24  7:09       ` Alasdair G Kergon
2009-06-24  7:34         ` NeilBrown [this message]
2009-06-24  7:38       ` Jens Axboe
2009-06-24  9:28         ` Neil Brown

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