Re: [PATCH 2/2] mm: oom: deduplicate victim selection code for memcg and global oom

From: Johannes Weiner
Date: Fri May 27 2016 - 13:25:16 EST


On Fri, May 27, 2016 at 05:17:42PM +0300, Vladimir Davydov wrote:
> When selecting an oom victim, we use the same heuristic for both memory
> cgroup and global oom. The only difference is the scope of tasks to
> select the victim from. So we could just export an iterator over all
> memcg tasks and keep all oom related logic in oom_kill.c, but instead we
> duplicate pieces of it in memcontrol.c reusing some initially private
> functions of oom_kill.c in order to not duplicate all of it. That looks
> ugly and error prone, because any modification of select_bad_process
> should also be propagated to mem_cgroup_out_of_memory.
>
> Let's rework this as follows: keep all oom heuristic related code
> private to oom_kill.c and make oom_kill.c use exported memcg functions
> when it's really necessary (like in case of iterating over memcg tasks).
>
> Signed-off-by: Vladimir Davydov <vdavydov@xxxxxxxxxxxxx>

Cool work!

I'll do a full review after the rebase on top of Michal's stuff.