linux-kernel - Re: [PATCH 3/8] cgroup: use cgroup_lock_live_group(parent) in cgroup

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <CAOS58YM+kRtspVUzmnSmOmrDoNS_kF6KA02zWGxqH5FUcRWo1Q@mail.gmail.com>
Date:	Thu, 1 Nov 2012 07:52:24 -0700
From:	Tejun Heo <tj@...nel.org>
To:	Michal Hocko <mhocko@...e.cz>
Cc:	lizefan@...wei.com, hannes@...xchg.org, bsingharora@...il.com,
	kamezawa.hiroyu@...fujitsu.com,
	containers@...ts.linux-foundation.org, cgroups@...r.kernel.org,
	linux-kernel@...r.kernel.org
Subject: Re: [PATCH 3/8] cgroup: use cgroup_lock_live_group(parent) in cgroup_create()

Hey, Michal.

On Thu, Nov 1, 2012 at 2:16 AM, Michal Hocko <mhocko@...e.cz> wrote:
> I am not sure I understand. What does deactivate_super has to do with
> the above suggestion? cgroup_lock_live_group will take the cgroup_mutex
> on the success or frees the previously allocated&unused memory. The
> only thing I was suggesting is to do cgroup_lock_live_group first and
> allocate the cgroup only if it doesn't fail.

It complicates updates to the error exit path. You end up having to
update a lot more and it's not like grabbing lock first is
substantially better in any way, so why bother?

Thanks.

-- 
tejun
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/