Date: Thu, 16 Dec 2010 16:07:57 +0100
From: Oleg Nesterov <oleg@redhat.com>
To: Mike Galbraith <efault@gmx.de>
Cc: linux-tip-commits@vger.kernel.org, linux-kernel@vger.kernel.org,
        hpa@zytor.com, mingo@redhat.com, mathieu.desnoyers@efficios.com,
        a.p.zijlstra@chello.nl, torvalds@linux-foundation.org, pjt@google.com,
        markus@trippelsdorf.de, tglx@linutronix.de, mingo@elte.hu
Subject: Re: [tip:sched/core] sched: Add 'autogroup' scheduling feature:
	automated per session task groups
Message-ID: <20101216150757.GA5841@redhat.com>
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On 12/16, Mike Galbraith wrote:
>
> I'd also have to disable interrupts though,

Even irq_disable can't help, I think.

> so may as well just lock it.

this also looks simpler.

> I didn't do the -ESRCH or no display bit.  As far as autogroup is
> concerned, if you couldn't lock, it's history, so belongs to init.

Agreed. I considered this option too, but I was worried about
sched_group_set_shares(root).

However, as you pointed out,

> sched_group_set_shares() does the right thing, says no to changing the
> root task group's shares.

Aha, I see, thanks.


I believe the patch is correct and closes the hole.

Oleg.

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