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Date: Fri, 14 Oct 2011 14:15:49 +0200
From: Frederic Weisbecker <fweisbec@gmail.com>
To: Ben Blum <bblum@andrew.cmu.edu>
Cc: Andrew Morton <akpm@linux-foundation.org>, Oleg Nesterov <oleg@redhat.com>,
        linux-kernel@vger.kernel.org, NeilBrown <neilb@suse.de>,
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        Balbir Singh <bsingharora@gmail.com>,
        Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>,
        KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Subject: Re: [PATCH 1/2] cgroups: use sighand lock instead of tasklist_lock
 in cgroup_attach_proc
Message-ID: <20111014121547.GK14968@somewhere>
References: <20110727171101.5e32d8eb@notabene.brown>
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Hi Ben,

On Thu, Oct 13, 2011 at 08:31:15PM -0400, Ben Blum wrote:
> Use sighand lock instead of tasklist_lock in cgroup_attach_proc.

Could you please feed more the changelog to explain the reason of
the change? Well, the reason of converting tasklist_lock based locking to
something more granular is almost obvious these days, but
it would be nice to know why it is safe to do so. And what exactly
that protects.

Thanks.