mirror of https://lore.kernel.org/lkml/
 help / color / mirror / Atom feed
From: Christoph Hellwig <hch@infradead.org>
To: Mark McLoughlin <markmc@redhat.com>,
	device-mapper development <dm-devel@redhat.com>,
	Jens Axboe <jens.axboe@oracle.com>,
	Rusty Russell <rusty@rustcorp.com.au>,
	linux-kernel <linux-kernel@vger.kernel.org>,
	virtualization <virtualization@lists.linux-foundation.org>,
	Mikulas Patocka <mpatocka@redhat.com>
Subject: Re: [dm-devel] [PATCH] block: silently error unsupported empty barriers too
Date: Thu, 6 Aug 2009 08:22:21 -0400	[thread overview]
Message-ID: <20090806122221.GA5175@infradead.org> (raw)
In-Reply-To: <20090806114550.GL29899@agk-dp.fab.redhat.com>

On Thu, Aug 06, 2009 at 12:45:50PM +0100, Alasdair G Kergon wrote:
> On Thu, Aug 06, 2009 at 12:14:17PM +0100, Mark McLoughlin wrote:
> > We should error all barriers, even empty barriers, on devices like
> > virtio_blk which don't support them.
>  
> Have you considered whether or not virtio_blk actually needs to
> support empty barriers?

virtio_blk on kvm does not support any barriers at all, similar to many
other drivers out there.  If the queue flags say we don't support
barriers higher layers should not submit any barrier requests.


  reply	other threads:[~2009-08-06 12:22 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-08-06 11:14 Mark McLoughlin
2009-08-06 11:45 ` [dm-devel] " Alasdair G Kergon
2009-08-06 12:22   ` Christoph Hellwig [this message]
2009-08-07  1:50   ` Mikulas Patocka
2009-10-28 20:19     ` Andrew Patterson
2009-10-28 21:03       ` Mike Snitzer
2009-10-29  7:45         ` Jens Axboe

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20090806122221.GA5175@infradead.org \
    --to=hch@infradead.org \
    --cc=dm-devel@redhat.com \
    --cc=jens.axboe@oracle.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=markmc@redhat.com \
    --cc=mpatocka@redhat.com \
    --cc=rusty@rustcorp.com.au \
    --cc=virtualization@lists.linux-foundation.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox

Powered by JetHome