From: Vivek Goyal <vgoyal@redhat.com>
To: Peter Zijlstra <peterz@infradead.org>
Cc: "Jun'ichi Nomura" <j-nomura@ce.jp.nec.com>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
device-mapper development <dm-devel@redhat.com>,
Tejun Heo <tj@kernel.org>, Jens Axboe <axboe@kernel.dk>,
Alasdair G Kergon <agk@redhat.com>,
"Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Subject: Re: [PATCH 2/2] dm: stay in blk_queue_bypass until queue becomes initialized
Date: Mon, 29 Oct 2012 13:13:46 -0400 [thread overview]
Message-ID: <20121029171346.GC3308@redhat.com> (raw)
In-Reply-To: <1351529115.24721.40.camel@twins>
On Mon, Oct 29, 2012 at 05:45:15PM +0100, Peter Zijlstra wrote:
> On Mon, 2012-10-29 at 12:38 -0400, Vivek Goyal wrote:
> > Ok, so the question is what's wrong with calling synchronize_rcu() inside
> > a mutex with CONFIG_PREEMPT=y. I don't know. Ccing paul mckenney and
> > peterz.
>
> int blkcg_activate_policy(struct request_queue *q,
>
> {
>
> ...
>
> preloaded = !radix_tree_preload(GFP_KERNEL);
>
> blk_queue_bypass_start(q);
>
>
>
>
> where:
>
> int radix_tree_preload(gfp_t gfp_mask)
> {
> struct radix_tree_preload *rtp;
> struct radix_tree_node *node;
> int ret = -ENOMEM;
>
> preempt_disable();
>
>
> Seems obvious why it explodes..
Oh right. Thanks Peter. So just calling blk_queue_bypass_start() before
radix_tree_preload() should fix it. Junichi, can you please give it
a try.
Thanks
Vivek
next prev parent reply other threads:[~2012-10-29 17:14 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-10-25 9:41 [PATCH 2/2] dm: stay in blk_queue_bypass until queue becomes initialized Jun'ichi Nomura
2012-10-26 1:42 ` Jun'ichi Nomura
2012-10-26 20:21 ` Vivek Goyal
2012-10-29 10:15 ` Jun'ichi Nomura
2012-10-29 16:38 ` Vivek Goyal
2012-10-29 16:45 ` Peter Zijlstra
2012-10-29 17:13 ` Vivek Goyal [this message]
2012-10-30 2:25 ` [PATCH] blkcg: fix "scheduling while atomic" in blk_queue_bypass_start Jun'ichi Nomura
2012-10-30 13:21 ` Vivek Goyal
2013-01-08 7:31 ` [PATCH repost] " Jun'ichi Nomura
2013-01-09 15:52 ` Vivek Goyal
2013-01-09 15:55 ` Tejun Heo
2013-02-26 4:53 ` Jun'ichi Nomura
2012-10-29 16:55 ` [PATCH 2/2] dm: stay in blk_queue_bypass until queue becomes initialized Paul E. McKenney
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=20121029171346.GC3308@redhat.com \
--to=vgoyal@redhat.com \
--cc=agk@redhat.com \
--cc=axboe@kernel.dk \
--cc=dm-devel@redhat.com \
--cc=j-nomura@ce.jp.nec.com \
--cc=linux-kernel@vger.kernel.org \
--cc=paulmck@linux.vnet.ibm.com \
--cc=peterz@infradead.org \
--cc=tj@kernel.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;
as well as URLs for NNTP newsgroup(s).