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Date: Wed, 24 Feb 2010 15:28:31 +0200
Message-ID: <cc557aab1002240528t28eae36dj976525be2fcf7246@mail.gmail.com>
Subject: Re: [PATCH -mm] cgroups: fix failure path in cgroup_write_event_control()
From: "Kirill A. Shutemov" <kirill@shutemov.name>
To: Li Zefan <lizf@cn.fujitsu.com>
Cc: Andrew Morton <akpm@linux-foundation.org>, Paul Menage <menage@google.com>,
       KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>,
       LKML <linux-kernel@vger.kernel.org>,
       "containers@lists.osdl.org" <containers@lists.osdl.org>
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On Wed, Feb 24, 2010 at 5:22 AM, Li Zefan <lizf@cn.fujitsu.com> wrote:
> How to reproduce:
>
>  # mount -t cgroup -o memory xxx /cgroup
>  # mkdir /cgroup/tmp
>  # ./cgroup_event_listener /cgroup/tmp/cgroup.event_control abc
>  ^C
>  # rmdir /cgroup/tmp
>  # cat /proc/cgroups | grep memory
>  memory  2       2       1         (should be "2 1 1")
>  # umount /cgroup
>  (failed!)
>
> Using a single goto label to cleanup multi failure paths can
> get things wrong quite easily, while multi labels makes the
> code cleaner.

I disagree.
It's easer to make mistake on changing code with multi failure
paths, if you want to move a code within function.