From: Jens Axboe <axboe@kernel.dk>
To: Tejun Heo <tj@kernel.org>, Hong Zhiguo <honkiko@gmail.com>
Cc: vgoyal@redhat.com, cgroups@vger.kernel.org,
linux-kernel@vger.kernel.org,
Hong Zhiguo <zhiguohong@tencent.com>
Subject: Re: [PATCH] blkcg: have bh disable for 32bit UP system reading 64bit stats
Date: Wed, 20 Nov 2013 10:31:31 -0700 [thread overview]
Message-ID: <528CF1F3.7020106@kernel.dk> (raw)
In-Reply-To: <20131120172413.GN28946@htj.dyndns.org>
On 11/20/2013 10:24 AM, Tejun Heo wrote:
> On Wed, Nov 06, 2013 at 07:14:44PM +0800, Hong Zhiguo wrote:
>> From: Hong Zhiguo <zhiguohong@tencent.com>
>>
>> Update of blkg_stat and blkg_rwstat may happen in bh context.
>> While u64_stats_fetch_retry is only preempt_disable on 32bit
>> UP system. This is not enough to avoid preemption by bh and
>> may read strange 64 bit value.
>>
>> Signed-off-by: Hong Zhiguo <zhiguohong@tencent.com>
>
> Acked-by: Tejun Heo <tj@kernel.org>
>
> Jens, can you please pick this one up? This probably needs to be
> tagged for stable too.
Yeah will do, thanks.
--
Jens Axboe
prev parent reply other threads:[~2013-11-20 17:31 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-11-06 11:14 [PATCH] blkcg: have bh disable for 32bit UP system reading 64bit stats Hong Zhiguo
2013-11-20 17:24 ` Tejun Heo
2013-11-20 17:31 ` Jens Axboe [this message]
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=528CF1F3.7020106@kernel.dk \
--to=axboe@kernel.dk \
--cc=cgroups@vger.kernel.org \
--cc=honkiko@gmail.com \
--cc=linux-kernel@vger.kernel.org \
--cc=tj@kernel.org \
--cc=vgoyal@redhat.com \
--cc=zhiguohong@tencent.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 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).