From: Michal Hocko <mhocko@kernel.org>
To: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Cc: Andrew Morton <akpm@linux-foundation.org>,
linux-mm@kvack.org, Johannes Weiner <hannes@cmpxchg.org>,
LKML <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH 0/2] oom, memcg: do not report racy no-eligible OOM
Date: Fri, 11 Jan 2019 14:34:01 +0100 [thread overview]
Message-ID: <20190111133401.GA6997@dhcp22.suse.cz> (raw)
In-Reply-To: <0d67b389-91e2-18ab-b596-39361b895c89@i-love.sakura.ne.jp>
On Fri 11-01-19 21:40:52, Tetsuo Handa wrote:
[...]
> Did you notice that there is no
>
> "Killed process %d (%s) total-vm:%lukB, anon-rss:%lukB, file-rss:%lukB, shmem-rss:%lukB\n"
>
> line between
>
> [ 71.304703][ T9694] Memory cgroup out of memory: Kill process 9692 (a.out) score 904 or sacrifice child
>
> and
>
> [ 71.309149][ T54] oom_reaper: reaped process 9750 (a.out), now anon-rss:0kB, file-rss:0kB, shmem-rss:185532kB
>
> ? Then, you will find that [ T9694] failed to reach for_each_process(p) loop inside
> __oom_kill_process() in the first round of out_of_memory() call because
> find_lock_task_mm() == NULL at __oom_kill_process() because Ctrl-C made that victim
> complete exit_mm() before find_lock_task_mm() is called.
OK, so we haven't killed anything because the victim has exited by the
time we wanted to do so. We still have other tasks sharing that mm
pending and not killed because nothing has killed them yet, right?
How come the oom reaper could act on this oom event at all then?
What am I missing?
--
Michal Hocko
SUSE Labs
next prev parent reply other threads:[~2019-01-11 13:34 UTC|newest]
Thread overview: 28+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-01-07 14:38 [PATCH 0/2] oom, memcg: do not report racy no-eligible OOM Michal Hocko
2019-01-07 14:38 ` [PATCH 1/2] mm, oom: marks all killed tasks as oom victims Michal Hocko
2019-01-07 20:58 ` Tetsuo Handa
2019-01-08 8:11 ` Michal Hocko
2019-01-07 14:38 ` [PATCH 2/2] memcg: do not report racy no-eligible OOM tasks Michal Hocko
2019-01-07 20:59 ` Tetsuo Handa
2019-01-08 8:14 ` Michal Hocko
2019-01-08 10:39 ` Tetsuo Handa
2019-01-08 11:46 ` Michal Hocko
2019-01-08 8:35 ` kbuild test robot
2019-01-08 9:39 ` Michal Hocko
2019-01-11 0:23 ` [kbuild-all] " Rong Chen
2019-01-08 14:21 ` [PATCH 3/2] memcg: Facilitate termination of memcg OOM victims Tetsuo Handa
2019-01-08 14:38 ` Michal Hocko
2019-01-09 11:03 ` [PATCH 0/2] oom, memcg: do not report racy no-eligible OOM Michal Hocko
2019-01-09 11:34 ` Tetsuo Handa
2019-01-09 12:02 ` Michal Hocko
2019-01-10 23:59 ` Tetsuo Handa
2019-01-11 10:25 ` Tetsuo Handa
2019-01-11 11:33 ` Michal Hocko
2019-01-11 12:40 ` Tetsuo Handa
2019-01-11 13:34 ` Michal Hocko [this message]
2019-01-11 14:31 ` Tetsuo Handa
2019-01-11 15:07 ` Michal Hocko
2019-01-11 15:37 ` Tetsuo Handa
2019-01-11 16:45 ` Michal Hocko
2019-01-12 10:52 ` Tetsuo Handa
2019-01-13 17:36 ` Michal Hocko
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20190111133401.GA6997@dhcp22.suse.cz \
--to=mhocko@kernel.org \
--cc=akpm@linux-foundation.org \
--cc=hannes@cmpxchg.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=penguin-kernel@i-love.sakura.ne.jp \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).