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Date: Thu, 5 Apr 2012 15:58:54 -0700
From: Tejun Heo <tj@kernel.org>
To: David Rientjes <rientjes@google.com>
Cc: Mike Galbraith <mgalbraith@suse.de>,
        Andrew Morton <akpm@linux-foundation.org>,
        Ingo Molnar <mingo@redhat.com>,
        Peter Zijlstra <a.p.zijlstra@chello.nl>,
        Paul Menage <paul@paulmenage.org>, LKML <linux-kernel@vger.kernel.org>,
        Li Zefan <lizefan@huawei.com>
Subject: Re: [patch 0/2] cpusets, cpu_cgroup: disallow attaching kthreadd
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Hello,

On Thu, Apr 05, 2012 at 03:55:11PM -0700, David Rientjes wrote:
> > I can see your point but the problem is that it conflicts with the
> > long term direction cgroup is taking and that cgroup seems generally
> > over-engineered to allow too many things which aren't too necessary to
> > the point where it's a giant pain in the ass for the subsystems and
> > people involved, so I'm far more likely to go for chopping down and
> > restricting stuff if it's not strictly necessary.
> 
> How does kthreadd's placement conflict with the long-term direction of 
> cgroups?

Because there's only single hierarchy, random subsystem saying no on
->can_attach() doesn't work.

Thanks.

-- 
tejun