From: Tejun Heo <tj-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
To: Kent Overstreet <koverstreet-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org>
Cc: linux-bcache-u79uwXL29TY76Z2rM5mHXA@public.gmane.org,
linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org,
dm-devel-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org,
axboe-tSWWG44O7X1aa/9Udqfwiw@public.gmane.org,
Vivek Goyal <vgoyal-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>,
Mikulas Patocka
<mpatocka-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>,
bharrosh-C4P08NqkoRlBDgjK7y7TUQ@public.gmane.org,
david-FqsqvQoI3Ljby3iVrkZq2A@public.gmane.org
Subject: Re: [PATCH 2/2] block: Avoid deadlocks with bio allocation by stacking drivers
Date: Mon, 10 Sep 2012 16:13:26 -0700 [thread overview]
Message-ID: <20120910231326.GG7677@google.com> (raw)
In-Reply-To: <20120910220910.GB7677-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org>
Hello, again.
On Mon, Sep 10, 2012 at 03:09:10PM -0700, Tejun Heo wrote:
> I'm still a bit scared but think this is correct.
>
> Acked-by: Tejun Heo <tj-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
>
> One last thing is that we may want to add @name on bioset creation so
> that we can name the workqueue properly but that's for another patch.
Yet another thing that I noticed in a different discussion.
http://thread.gmane.org/gmane.linux.network.drbd.devel/2130
Before this, I think bios didn't get reordered while they're traveling
down the stacked bio drivers. After this, I don't think that's true
anymore. Currently, IIRC, we don't have any ordering functionality at
bio interface, so I don't think this breaks anything but this can lead
to stupidly subtle bugs if the upper layer is making assumption on
ordering somehow. It's something which at least should be noted, I
think. Whether we want to update the code so that ordering is
maintained, I don't know. I hope not. It's already crazy complex. :(
Thanks.
--
tejun
WARNING: multiple messages have this Message-ID (diff)
From: Tejun Heo <tj@kernel.org>
To: Kent Overstreet <koverstreet@google.com>
Cc: linux-bcache@vger.kernel.org, linux-kernel@vger.kernel.org,
dm-devel@redhat.com, axboe@kernel.dk,
Vivek Goyal <vgoyal@redhat.com>,
Mikulas Patocka <mpatocka@redhat.com>,
bharrosh@panasas.com, david@fromorbit.com
Subject: Re: [PATCH 2/2] block: Avoid deadlocks with bio allocation by stacking drivers
Date: Mon, 10 Sep 2012 16:13:26 -0700 [thread overview]
Message-ID: <20120910231326.GG7677@google.com> (raw)
In-Reply-To: <20120910220910.GB7677@google.com>
Hello, again.
On Mon, Sep 10, 2012 at 03:09:10PM -0700, Tejun Heo wrote:
> I'm still a bit scared but think this is correct.
>
> Acked-by: Tejun Heo <tj@kernel.org>
>
> One last thing is that we may want to add @name on bioset creation so
> that we can name the workqueue properly but that's for another patch.
Yet another thing that I noticed in a different discussion.
http://thread.gmane.org/gmane.linux.network.drbd.devel/2130
Before this, I think bios didn't get reordered while they're traveling
down the stacked bio drivers. After this, I don't think that's true
anymore. Currently, IIRC, we don't have any ordering functionality at
bio interface, so I don't think this breaks anything but this can lead
to stupidly subtle bugs if the upper layer is making assumption on
ordering somehow. It's something which at least should be noted, I
think. Whether we want to update the code so that ordering is
maintained, I don't know. I hope not. It's already crazy complex. :(
Thanks.
--
tejun
next prev parent reply other threads:[~2012-09-10 23:13 UTC|newest]
Thread overview: 48+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-09-07 22:12 [PATCH 0/2] Avoid deadlocks with bio allocation Kent Overstreet
2012-09-07 22:12 ` Kent Overstreet
[not found] ` <1347055973-11581-1-git-send-email-koverstreet-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org>
2012-09-07 22:12 ` [PATCH 1/2] block: Reorder struct bio_set Kent Overstreet
2012-09-07 22:12 ` Kent Overstreet
2012-09-07 22:12 ` [PATCH 2/2] block: Avoid deadlocks with bio allocation by stacking drivers Kent Overstreet
[not found] ` <1347055973-11581-3-git-send-email-koverstreet-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org>
2012-09-08 19:36 ` Tejun Heo
2012-09-08 19:36 ` Tejun Heo
[not found] ` <20120908193641.GB12773-RcKxWJ4Cfj1J2suj2OqeGauc2jM2gXBXkQQo+JxHRPFibQn6LdNjmg@public.gmane.org>
2012-09-10 0:28 ` Kent Overstreet
2012-09-10 0:28 ` Kent Overstreet
[not found] ` <20120910002810.GA23241-jC9Py7bek1znysI04z7BkA@public.gmane.org>
2012-09-10 15:25 ` Vivek Goyal
2012-09-10 15:25 ` Vivek Goyal
2012-09-10 17:22 ` Tejun Heo
2012-09-10 17:22 ` Tejun Heo
[not found] ` <20120910172210.GC14103-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org>
2012-09-10 20:24 ` Kent Overstreet
2012-09-10 20:24 ` Kent Overstreet
[not found] ` <20120910202435.GG16360-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org>
2012-09-10 20:40 ` Tejun Heo
2012-09-10 20:40 ` Tejun Heo
[not found] ` <20120910204010.GA32310-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org>
2012-09-10 21:33 ` Kent Overstreet
2012-09-10 21:33 ` Kent Overstreet
[not found] ` <20120910213349.GH16360-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org>
2012-09-10 21:37 ` Tejun Heo
2012-09-10 21:37 ` Tejun Heo
2012-09-10 21:56 ` Kent Overstreet
[not found] ` <20120910215633.GA19739-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org>
2012-09-10 22:09 ` Tejun Heo
2012-09-10 22:09 ` Tejun Heo
[not found] ` <20120910220910.GB7677-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org>
2012-09-10 22:50 ` [dm-devel] " Alasdair G Kergon
2012-09-10 22:50 ` Alasdair G Kergon
[not found] ` <20120910225057.GA10477-FDJ95KluN3Z0klwcnFlA1dvLeJWuRmrY@public.gmane.org>
2012-09-10 23:01 ` Tejun Heo
2012-09-10 23:01 ` Tejun Heo
2012-09-10 23:06 ` Kent Overstreet
[not found] ` <CAOS58YO5puV2iPhwe0vbyEydPnR=eWPStNRm=xEpMeo-TMHCaw-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
2012-09-10 23:09 ` Alasdair G Kergon
2012-09-10 23:09 ` Alasdair G Kergon
[not found] ` <20120910230917.GB10477-FDJ95KluN3Z0klwcnFlA1dvLeJWuRmrY@public.gmane.org>
2012-09-10 23:35 ` Tejun Heo
2012-09-10 23:35 ` Tejun Heo
[not found] ` <20120910233502.GH7677-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org>
2012-09-10 23:45 ` Alasdair G Kergon
2012-09-10 23:45 ` Alasdair G Kergon
2012-09-10 23:01 ` Kent Overstreet
2012-09-10 23:01 ` Kent Overstreet
2012-09-10 23:13 ` Tejun Heo [this message]
2012-09-10 23:13 ` Tejun Heo
2012-09-11 18:36 ` Muthu Kumar
2012-09-11 18:36 ` Muthu Kumar
[not found] ` <CAFR8ued=Le4B4i_Rf4eECXsVgKvce9J7bO9sDSS91PFzBZ6j5w-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
2012-09-11 18:45 ` Tejun Heo
2012-09-11 18:45 ` Tejun Heo
[not found] ` <20120911184553.GT7677-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org>
2012-09-11 18:58 ` Muthu Kumar
2012-09-11 18:58 ` Muthu Kumar
2012-09-11 19:31 ` Kent Overstreet
[not found] ` <20120911193124.GI19739-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org>
2012-09-11 20:00 ` Muthu Kumar
2012-09-11 20:00 ` Muthu Kumar
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=20120910231326.GG7677@google.com \
--to=tj-dgejt+ai2ygdnm+yrofe0a@public.gmane.org \
--cc=axboe-tSWWG44O7X1aa/9Udqfwiw@public.gmane.org \
--cc=bharrosh-C4P08NqkoRlBDgjK7y7TUQ@public.gmane.org \
--cc=david-FqsqvQoI3Ljby3iVrkZq2A@public.gmane.org \
--cc=dm-devel-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org \
--cc=koverstreet-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org \
--cc=linux-bcache-u79uwXL29TY76Z2rM5mHXA@public.gmane.org \
--cc=linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org \
--cc=mpatocka-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org \
--cc=vgoyal-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.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 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.