Re: [PATCH] mm/memcontrol: Skip root memcg in memcg_memory_event_mm

From: Shakeel Butt
Date: Fri Dec 16 2022 - 01:42:20 EST


On Fri, Dec 16, 2022 at 09:43:02AM +0800, Haifeng Xu wrote:
>
>
> On 2022/12/16 02:18, Shakeel Butt wrote:
> > On Thu, Dec 15, 2022 at 09:19:07AM +0000, Haifeng Xu wrote:
> >> The memory events aren't supported on root cgroup, so there is no need
> >> to account MEMCG_OOM_KILL on root memcg.
> >>
> >
> > Can you explain the scenario where this is happening and causing issue
> > for you?
> >
> If the victim selected by oom killer belongs to root memcg, memcg_memory_event_mm
> still counts the MEMCG_OOM_KILL event. This behavior is meaningless because the
> flag of events/events.local in memory_files is CFTYPE_NOT_ON_ROOT. The root memcg
> does not count any memory event.
>

What about v1's memory.oom_control?