From: Tejun Heo <tj@kernel.org>
To: Frederic Weisbecker <fweisbec@gmail.com>
Cc: tip-bot for Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>,
linux-tip-commits@vger.kernel.org, linux-kernel@vger.kernel.org,
hpa@zytor.com, mingo@redhat.com, a.p.zijlstra@chello.nl,
pjt@google.com, tglx@linutronix.de, mingo@elte.hu
Subject: Re: [tip:sched/core] sched: Fix cgroup movement of forking process
Date: Wed, 21 Dec 2011 18:01:57 -0800 [thread overview]
Message-ID: <20111222020157.GR9213@google.com> (raw)
In-Reply-To: <20111222015440.GM17668@somewhere>
Hello,
On Thu, Dec 22, 2011 at 02:54:42AM +0100, Frederic Weisbecker wrote:
> > Frederic, so, it seems we actually have race conditions here. I
> > really wish cgroup made sure that things like this can't happen even
> > if we pay a bit of overhead in relatively cold paths. I could be
> > being unrealistic tho. Any ideas?
>
> Hmm, I'm a bit confused about the issue. But doesn't this patch fix the issue?
Yeah, I was just saying it would be nice if we don't have to fix the
issue.
> Also the parent can't be calling sched_fork() and cgroup_exit() at
> the same time.
Hmmm... so this one can't happen anymore but there are races involving
cgroup_exit() which doesn't have anything to do with threadgroup lock
(Dalsuke has more patches), so this doesn't really matter. Let's
forget about this thread.
Thanks.
--
tejun
next prev parent reply other threads:[~2011-12-22 2:02 UTC|newest]
Thread overview: 22+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-12-13 6:57 [PATCH 0/3] sched: some fixes for vruntime calculation related to cgroup movement Daisuke Nishimura
2011-12-13 6:57 ` [PATCH 1/3] sched: fix cgroup movement of newly created process Daisuke Nishimura
2011-12-13 12:01 ` Paul Turner
2011-12-14 1:04 ` Daisuke Nishimura
2011-12-13 12:41 ` Peter Zijlstra
2011-12-14 1:05 ` Daisuke Nishimura
2011-12-13 6:58 ` [PATCH 2/3] sched: fix cgroup movement of forking process Daisuke Nishimura
2011-12-13 12:22 ` Paul Turner
2011-12-13 6:59 ` [PATCH 3/3] sched: fix cgroup movement of waking process Daisuke Nishimura
2011-12-13 12:24 ` Paul Turner
2011-12-15 5:35 ` [PATCH -tip 0/3] sched: some fixes for vruntime calculation related to cgroup movement(v2) Daisuke Nishimura
2011-12-15 5:36 ` [PATCH 1/3] sched: fix cgroup movement of newly created process Daisuke Nishimura
2011-12-21 11:45 ` [tip:sched/core] sched: Fix " tip-bot for Daisuke Nishimura
2011-12-15 5:36 ` [PATCH 2/3] sched: fix cgroup movement of forking process Daisuke Nishimura
2011-12-21 11:44 ` [tip:sched/core] sched: Fix " tip-bot for Daisuke Nishimura
2011-12-21 17:26 ` Tejun Heo
2011-12-21 17:37 ` Tejun Heo
2011-12-22 1:54 ` Frederic Weisbecker
2011-12-22 2:01 ` Tejun Heo [this message]
2011-12-15 5:37 ` [PATCH 3/3] sched: fix cgroup movement of waking process Daisuke Nishimura
2011-12-21 11:45 ` [tip:sched/core] sched: Fix " tip-bot for Daisuke Nishimura
2011-12-19 2:55 ` [PATCH -tip 0/3] sched: some fixes for vruntime calculation related to cgroup movement(v2) Daisuke Nishimura
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