Re: [PATCH 2/2] cgroup: reset css on destruction

From: Johannes Weiner
Date: Tue Mar 01 2016 - 14:55:50 EST


On Tue, Mar 01, 2016 at 07:56:30PM +0300, Vladimir Davydov wrote:
> From: Vladimir Davydov <vdavydov@xxxxxxxxxxxxx>
> Subject: [PATCH] cgroup: reset css on destruction
>
> An associated css can be around for quite a while after a cgroup
> directory has been removed. In general, it makes sense to reset it to
> defaults so as not to worry about any remnants. For instance, memory
> cgroup needs to reset memory.low, otherwise pages charged to a dead
> cgroup might never get reclaimed. There's ->css_reset callback, which
> would fit perfectly for the purpose. Currently, it's only called when a
> subsystem is disabled in the unified hierarchy and there are other
> subsystems dependant on it. Let's call it on css destruction as well.
>
> Suggested-by: Johannes Weiner <hannes@xxxxxxxxxxx>
> Signed-off-by: Vladimir Davydov <vdavydov@xxxxxxxxxxxxx>

It's already in a git tree, but FWIW

Acked-by: Johannes Weiner <hannes@xxxxxxxxxxx>