Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
Date:   Fri, 11 Jun 2021 10:27:43 +0100
From:   Aaron Tomlin <atomlin@redhat.com>
To:     Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Cc:     Michal Hocko <mhocko@suse.com>, Waiman Long <llong@redhat.com>,
        Shakeel Butt <shakeelb@google.com>,
        Linux MM <linux-mm@kvack.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Vlastimil Babka <vbabka@suse.cz>,
        LKML <linux-kernel@vger.kernel.org>
Subject: Re: [RFC PATCH] mm/oom_kill: allow oom kill allocating task for
 non-global case
Message-ID: <20210611092743.lsxfavezj3sps5ay@ava.usersys.com>
References: <YL51Tp/3jVHUrpuj@dhcp22.suse.cz>
 <YL57rLFwAo7EpYeH@dhcp22.suse.cz>
 <353d012f-e8d4-c54c-b33e-54737e1a0115@redhat.com>
 <YL8MjSteKeO7w0il@dhcp22.suse.cz>
 <20210609143534.v65qknfihqimiivd@ava.usersys.com>
 <YMHivM+0DRYXzAD0@dhcp22.suse.cz>
 <20210610122323.6geriip66jjmdstj@ava.usersys.com>
 <YMII3OMPoZPuCe0r@dhcp22.suse.cz>
 <20210610133644.zpoqfvlchaey24za@ava.usersys.com>
 <c205367d-f47e-61f3-3aed-fd8142a0010f@i-love.sakura.ne.jp>
MIME-Version: 1.0
Content-Type: text/plain; charset=utf-8
Content-Disposition: inline
In-Reply-To: <c205367d-f47e-61f3-3aed-fd8142a0010f@i-love.sakura.ne.jp>
Precedence: bulk

On Thu 2021-06-10 23:06 +0900, Tetsuo Handa wrote:
> Yes, marking ineligible (i.e. oom_badness() returning LONG_MIN) tasks
> would be useful.

Sure. I'll send a patch to append this information; and the reason why
i.e. "yes: oom skipped" or "yes: oom score" or "yes: vfork" to dump_task()
with the use of some helper function e.g. is_task_eligible_oom().

> By the way, was the task namely "node" (i.e. PID 1703345) multithreaded
> program?

Unfortunately, I cannot confirm since the scenario/or situation is no
longer present in the vmcore; albeit, I believe so.

> Your kernel might want commit 7775face207922ea ("memcg: killed threads
> should not invoke memcg OOM killer").

Tetsuo-san,

Yes, this does appear to be a match.
Thanks for this.


Kind regards,

-- 
Aaron Tomlin