From: Dave Chinner <david@fromorbit.com>
To: Mikulas Patocka <mpatocka@redhat.com>
Cc: Andi Kleen <andi-suse@firstfloor.org>,
linux-kernel@vger.kernel.org, xfs@oss.sgi.com,
Andi Kleen <andi@firstfloor.org>,
Alasdair G Kergon <agk@redhat.com>, Milan Broz <mbroz@redhat.com>
Subject: Re: Device loses barrier support (was: Fixed patch for simple barriers.)
Date: Sun, 7 Dec 2008 15:17:11 +1100 [thread overview]
Message-ID: <20081207041711.GA22525@disturbed> (raw)
In-Reply-To: <Pine.LNX.4.64.0812041139200.2434@hs20-bc2-1.build.redhat.com>
On Thu, Dec 04, 2008 at 11:45:44AM -0500, Mikulas Patocka wrote:
> > The write block with barrier bit varies, jbd/gfs2 do it synchronously
> > too and xfs does it asynchronously (with io done callbacks), but
>
> And how does xfs preserve write ordering, if the barrier asynchronously
> fails with -EOPNOTSUPP and there are other writes submitted after the
> barrier?
Doesn't matter. XFS executes journal state changes during the I/O
completion callbacks a layer above this resubmit code. Hence,
if the I/O is resubmitted before the completion callbacks are
run, it just appears that the I/O has taken longer than expected
and the state change is delayed....
Cheers,
Dave.
--
Dave Chinner
david@fromorbit.com
_______________________________________________
xfs mailing list
xfs@oss.sgi.com
http://oss.sgi.com/mailman/listinfo/xfs
WARNING: multiple messages have this Message-ID (diff)
From: Dave Chinner <david@fromorbit.com>
To: Mikulas Patocka <mpatocka@redhat.com>
Cc: Andi Kleen <andi@firstfloor.org>,
linux-kernel@vger.kernel.org, xfs@oss.sgi.com,
Alasdair G Kergon <agk@redhat.com>,
Andi Kleen <andi-suse@firstfloor.org>,
Milan Broz <mbroz@redhat.com>
Subject: Re: Device loses barrier support (was: Fixed patch for simple barriers.)
Date: Sun, 7 Dec 2008 15:17:11 +1100 [thread overview]
Message-ID: <20081207041711.GA22525@disturbed> (raw)
In-Reply-To: <Pine.LNX.4.64.0812041139200.2434@hs20-bc2-1.build.redhat.com>
On Thu, Dec 04, 2008 at 11:45:44AM -0500, Mikulas Patocka wrote:
> > The write block with barrier bit varies, jbd/gfs2 do it synchronously
> > too and xfs does it asynchronously (with io done callbacks), but
>
> And how does xfs preserve write ordering, if the barrier asynchronously
> fails with -EOPNOTSUPP and there are other writes submitted after the
> barrier?
Doesn't matter. XFS executes journal state changes during the I/O
completion callbacks a layer above this resubmit code. Hence,
if the I/O is resubmitted before the completion callbacks are
run, it just appears that the I/O has taken longer than expected
and the state change is delayed....
Cheers,
Dave.
--
Dave Chinner
david@fromorbit.com
next prev parent reply other threads:[~2008-12-07 4:27 UTC|newest]
Thread overview: 44+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <Pine.LNX.4.64.0812040009340.15169@hs20-bc2-1.build.redhat.com>
[not found] ` <20081204100050.GN6703@one.firstfloor.org>
2008-12-04 14:00 ` Device loses barrier support (was: Fixed patch for simple barriers.) Mikulas Patocka
2008-12-04 14:00 ` Mikulas Patocka
2008-12-04 14:20 ` Andi Kleen
2008-12-04 14:20 ` Andi Kleen
2008-12-04 14:17 ` Mikulas Patocka
2008-12-04 14:17 ` Mikulas Patocka
2008-12-04 14:58 ` Andi Kleen
2008-12-04 14:58 ` Andi Kleen
2008-12-04 16:45 ` Mikulas Patocka
2008-12-04 16:45 ` Mikulas Patocka
2008-12-04 17:48 ` Andi Kleen
2008-12-04 17:48 ` Andi Kleen
2008-12-04 17:53 ` Christoph Hellwig
2008-12-04 17:53 ` Christoph Hellwig
2008-12-04 19:37 ` Mikulas Patocka
2008-12-04 19:37 ` Mikulas Patocka
2008-12-04 22:15 ` Andi Kleen
2008-12-04 22:15 ` Andi Kleen
2008-12-04 23:08 ` Mikulas Patocka
2008-12-04 23:08 ` Mikulas Patocka
2008-12-05 0:48 ` Andi Kleen
2008-12-05 0:48 ` Andi Kleen
2008-12-05 1:16 ` Mikulas Patocka
2008-12-05 1:16 ` Mikulas Patocka
2008-12-05 1:37 ` Andi Kleen
2008-12-05 1:37 ` Andi Kleen
2008-12-05 2:21 ` Mikulas Patocka
2008-12-05 2:21 ` Mikulas Patocka
2008-12-05 3:09 ` Andi Kleen
2008-12-05 3:09 ` Andi Kleen
2008-12-05 11:52 ` Alan Cox
2008-12-05 11:52 ` Alan Cox
2008-12-05 12:29 ` Andi Kleen
2008-12-05 12:29 ` Andi Kleen
2008-12-05 3:26 ` Device loses barrier support Eric Sandeen
2008-12-05 3:26 ` Eric Sandeen
2008-12-07 4:17 ` Dave Chinner [this message]
2008-12-07 4:17 ` Device loses barrier support (was: Fixed patch for simple barriers.) Dave Chinner
2008-12-05 5:44 ` Device loses barrier support Timothy Shimmin
2008-12-05 5:44 ` Timothy Shimmin
[not found] <bFnGM-7mA-5@gated-at.bofh.it>
[not found] ` <bFpyX-1jh-15@gated-at.bofh.it>
[not found] ` <bFquY-2x2-5@gated-at.bofh.it>
[not found] ` <bFsnc-51o-37@gated-at.bofh.it>
[not found] ` <bFuyC-7Zt-11@gated-at.bofh.it>
[not found] ` <bFvuI-L8-29@gated-at.bofh.it>
[not found] ` <bFwTJ-2oc-13@gated-at.bofh.it>
[not found] ` <bFxwq-3g7-1@gated-at.bofh.it>
[not found] ` <bFxGa-3pz-1@gated-at.bofh.it>
[not found] ` <bFHvW-7up-5@gated-at.bofh.it>
[not found] ` <bFHPd-84I-13@gated-at.bofh.it>
2008-12-05 18:21 ` Device loses barrier support (was: Fixed patch for simple barriers.) Bodo Eggert
2008-12-05 18:21 ` Bodo Eggert
2008-12-05 18:41 ` Andi Kleen
2008-12-05 18:41 ` Andi Kleen
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=20081207041711.GA22525@disturbed \
--to=david@fromorbit.com \
--cc=agk@redhat.com \
--cc=andi-suse@firstfloor.org \
--cc=andi@firstfloor.org \
--cc=linux-kernel@vger.kernel.org \
--cc=mbroz@redhat.com \
--cc=mpatocka@redhat.com \
--cc=xfs@oss.sgi.com \
/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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.