From: Tejun Heo <tj@kernel.org>
To: Zefan Li <lizefan@huawei.com>
Cc: Mike Galbraith <umgwanakikbuti@gmail.com>,
LKML <linux-kernel@vger.kernel.org>,
Cgroups <cgroups@vger.kernel.org>
Subject: Re: [RFC][PATCH] cgroup: disallow subtree controller enable/disable while there are tasks
Date: Mon, 4 May 2015 12:15:00 -0400 [thread overview]
Message-ID: <20150504161500.GC1971@htj.duckdns.org> (raw)
In-Reply-To: <554745D1.1000206@huawei.com>
On Mon, May 04, 2015 at 06:11:29PM +0800, Zefan Li wrote:
> It's not safe if we enable/disable some controllers while there are
> tasks in the substree, because task migration can fail.
>
> For example rt bandwidth controller disallow having rt tasks in the
> cgroup if no bandwidth has been allocated, which is the case when
> a cgroup is just created.
>
> A kernel warning is triggered immediately by doing:
Well, the whole thing is behind the devel flag for a reason. Let's
see how we can resolve the RT case and then determine what to do.
Thanks.
--
tejun
prev parent reply other threads:[~2015-05-04 16:15 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-05-04 10:11 [RFC][PATCH] cgroup: disallow subtree controller enable/disable while there are tasks Zefan Li
2015-05-04 16:15 ` Tejun Heo [this message]
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