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Date: Wed, 22 Feb 2012 02:10:48 +0100
From: Frederic Weisbecker <fweisbec@gmail.com>
To: Tejun Heo <tj@kernel.org>
Cc: Mandeep Singh Baines <msb@chromium.org>,
        "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>,
        Li Zefan <lizf@cn.fujitsu.com>, LKML <linux-kernel@vger.kernel.org>,
        Oleg Nesterov <oleg@redhat.com>,
        Andrew Morton <akpm@linux-foundation.org>
Subject: Re: [PATCH 2/2] cgroup: Walk task list under tasklist_lock in
 cgroup_enable_task_cg_list
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On Tue, Feb 21, 2012 at 05:06:23PM -0800, Tejun Heo wrote:
> On Wed, Feb 22, 2012 at 02:04:34AM +0100, Frederic Weisbecker wrote:
> > > Guys, this is one time thing.  It happens *once* after boot and we're
> > > already holding exclusive lock.  There's no reason to optimize this at
> > > all.  Let's just keep it simple.
> > 
> > For now I agree. But one day the real time guys might eye that thing.
> 
> If the latency issue ever comes up, I think the right thing to do is
> just disable the lazy optimization.  ie. Just chain tasks from the
> beginning.

Yeah agreed.