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Date: Mon, 14 Nov 2016 19:58:17 +0100
From: Oleg Nesterov <oleg@redhat.com>
To: Ingo Molnar <mingo@kernel.org>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Mike Galbraith <efault@gmx.de>,
        Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: hartsjc@redhat.com, vbendel@redhat.com, vlovejoy@redhat.com,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH 2/2] sched/autogroup: a zombie thread must not use
 autogroup->tg
Message-ID: <20161114185817.GA15995@redhat.com>
References: <20161114184548.GA15954@redhat.com>
 <20161114184612.GA15968@redhat.com>
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On 11/14, Oleg Nesterov wrote:
>
> +void sched_autogroup_exit_task(struct task_struct *p)
> +{
> +	/*
> +	 * We are going to call exit_notify() and autogroup_move_group() can't
> +	 * see this thread after that: we can no longer use signal->autogroup.
> +	 * See the PF_EXITING check in task_wants_autogroup().
> +	 */
> +	sched_move_task(p);

We only need it if task_group_is_autogroup(task_group(p)) but then this code
will need even more comments, lets keep it simple.

Oleg.