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Date: Thu, 11 Dec 2008 09:09:15 -0800
Message-ID: <6599ad830812110909t5e268bcak31df359c516874d1@mail.gmail.com>
Subject: Re: [RFC][PATCH 1/3] CGroups: Add a per-subsystem hierarchy_mutex
From: Paul Menage <menage@google.com>
To: balbir@linux.vnet.ibm.com, menage@google.com,
       kamezawa.hiroyu@jp.fujitsu.com, containers@lists.linux-foundation.org,
       linux-kernel@vger.kernel.org, akpm@linux-foundation.org
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On Wed, Dec 10, 2008 at 10:29 PM, Balbir Singh
<balbir@linux.vnet.ibm.com> wrote:
>
> Seems reasonable, I was wondering if instead of acquiring a mutex per
> subsystem that shares the root, if we can collapse it to a single
> mutex and prevent cgroup from changing binding. Those are
> optimizations that we can think of later

You mean a single hierarchy_mutex per root? But given that one of the
things being protected is which root you're attached to, if you're
trying to prevent hierarchy changes then which root's hierarchy_mutex
would you lock?

Paul