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Date:   Thu, 21 Oct 2021 12:03:18 +0200
From:   Michal Hocko <mhocko@suse.com>
To:     Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Cc:     Vasily Averin <vvs@virtuozzo.com>,
        Johannes Weiner <hannes@cmpxchg.org>,
        Vladimir Davydov <vdavydov.dev@gmail.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Roman Gushchin <guro@fb.com>,
        Uladzislau Rezki <urezki@gmail.com>,
        Vlastimil Babka <vbabka@suse.cz>,
        Shakeel Butt <shakeelb@google.com>,
        Mel Gorman <mgorman@techsingularity.net>,
        cgroups@vger.kernel.org, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org, kernel@openvz.org
Subject: Re: [PATCH memcg 2/3] memcg: remove charge forcinig for dying tasks
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On Thu 21-10-21 00:20:02, Tetsuo Handa wrote:
> On 2021/10/20 23:57, Michal Hocko wrote:
> > One argument for removing it from here is the maintainability. Now you
> > have a memcg specific check which is not in sync with the oom. E.g.
> > out_of_memory does task_will_free_mem as the very first thing. You are
> > also automatically excluding oom killer for cases where that might make
> > a sense.
> 
> What makes it possible to remove this check?
> This check was added because task_will_free_mem() in out_of_memory() does NOT work.
> See commit 7775face207922ea ("memcg: killed threads should not invoke memcg OOM killer").

You are right. I've forgot about this and should have checked git blame.
Thanks for bringing this up!

-- 
Michal Hocko
SUSE Labs