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Subject: Re: [RFC][PATCH 3/5] Container Freezer: Implement freezer cgroup
	subsystem
From: Matt Helsley <matthltc@us.ibm.com>
To: Linux-Kernel <linux-kernel@vger.kernel.org>
Cc: Cedric Le Goater <clg@fr.ibm.com>, Paul Menage <menage@google.com>,
       Oren Laadan <orenl@cs.columbia.edu>,
       Linus Torvalds <torvalds@linux-foundation.org>,
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Date: Wed, 30 Apr 2008 15:30:49 -0700
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On Wed, 2008-04-30 at 14:28 -0700, Matt Helsley wrote:
> On Wed, 2008-04-23 at 23:47 -0700, Matt Helsley wrote:
> 
> <snip>

> > +	cgroup_lock();
> > +
> > +	if (cgroup_is_removed(cgroup)) {
> > +		retval = -ENODEV;
> > +		goto unlock;
> > +	}
> 
> I think this was copy/paste'd from cgroup_common_file_write() which
> modifies the cgroup hierarchy. However this function does not modify the
> cgroup hierarchy and we're not getting the cgroup from the task. So I
> don't think cgroup_lock()/unlock() are needed here. Paul, do you agree?

Oops! I didn't track the call chain correctly. Sorry for the noise...

Cheers,
	-Matt Helsley