From: Andrew Morton <akpm@linux-foundation.org>
To: Vasily Averin <vvs@virtuozzo.com>
Cc: Michal Hocko <mhocko@kernel.org>,
Johannes Weiner <hannes@cmpxchg.org>,
Vladimir Davydov <vdavydov.dev@gmail.com>,
Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>,
cgroups@vger.kernel.org, linux-mm@kvack.org,
linux-kernel@vger.kernel.org, kernel@openvz.org
Subject: Re: [PATCH mm v2] vmalloc: back off when the current task is OOM-killed
Date: Thu, 7 Oct 2021 12:55:41 -0700 [thread overview]
Message-ID: <20211007125541.db0f3ff2bdbd8fa7dc1db03d@linux-foundation.org> (raw)
In-Reply-To: <83efc664-3a65-2adb-d7c4-2885784cf109@virtuozzo.com>
On Tue, 5 Oct 2021 16:52:40 +0300 Vasily Averin <vvs@virtuozzo.com> wrote:
> Huge vmalloc allocation on heavy loaded node can lead to a global
> memory shortage. Task called vmalloc can have worst badness and
> be selected by OOM-killer, however taken fatal signal does not
> interrupt allocation cycle. Vmalloc repeat page allocaions
> again and again, exacerbating the crisis and consuming the memory
> freed up by another killed tasks.
>
> After a successful completion of the allocation procedure, a fatal
> signal will be processed and task will be destroyed finally.
> However it may not release the consumed memory, since the allocated
> object may have a lifetime unrelated to the completed task.
> In the worst case, this can lead to the host will panic
> due to "Out of memory and no killable processes..."
>
> This patch allows OOM-killer to break vmalloc cycle, makes OOM more
> effective and avoid host panic. It does not check oom condition directly,
> however, and breaks page allocation cycle when fatal signal was received.
>
> This may trigger some hidden problems, when caller does not handle
> vmalloc failures, or when rollaback after failed vmalloc calls own
> vmallocs inside. However all of these scenarios are incorrect:
> vmalloc does not guarantee successful allocation, it has never been called
> with __GFP_NOFAIL and threfore either should not be used for any rollbacks
> or should handle such errors correctly and not lead to critical
> failures.
>
This needed a little rework due to
https://lkml.kernel.org/r/20210928121040.2547407-1-chenwandun@huawei.com.
Please check and retest sometime?
--- a/mm/vmalloc.c~vmalloc-back-off-when-the-current-task-is-oom-killed
+++ a/mm/vmalloc.c
@@ -2887,6 +2887,9 @@ vm_area_alloc_pages(gfp_t gfp, int nid,
page = NULL;
while (nr_allocated < nr_pages) {
+ if (fatal_signal_pending(current))
+ break;
+
if (nid == NUMA_NO_NODE)
page = alloc_pages(gfp, order);
else
_
next prev parent reply other threads:[~2021-10-07 19:55 UTC|newest]
Thread overview: 34+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-09-10 12:39 [PATCH memcg] memcg: prohibit unconditional exceeding the limit of dying tasks Vasily Averin
2021-09-10 13:04 ` Tetsuo Handa
2021-09-10 13:20 ` Vasily Averin
2021-09-10 14:55 ` Michal Hocko
2021-09-13 8:29 ` Vasily Averin
2021-09-13 8:42 ` Michal Hocko
2021-09-17 8:06 ` [PATCH mm] vmalloc: back off when the current task is OOM-killed Vasily Averin
2021-09-19 23:31 ` Andrew Morton
2021-09-20 1:22 ` Tetsuo Handa
2021-09-20 10:59 ` Vasily Averin
2021-09-21 18:55 ` Andrew Morton
2021-09-22 6:18 ` Vasily Averin
2021-09-22 12:27 ` Michal Hocko
2021-09-23 6:49 ` Vasily Averin
2021-09-24 7:55 ` Michal Hocko
2021-09-27 9:36 ` Vasily Averin
2021-09-27 11:08 ` Michal Hocko
2021-10-05 13:52 ` [PATCH mm v2] " Vasily Averin
2021-10-05 14:00 ` Vasily Averin
2021-10-07 10:47 ` Michal Hocko
2021-10-07 19:55 ` Andrew Morton [this message]
2021-09-10 13:07 ` [PATCH memcg] memcg: prohibit unconditional exceeding the limit of dying tasks Vasily Averin
2021-09-13 7:51 ` Vasily Averin
2021-09-13 8:39 ` Michal Hocko
2021-09-13 9:37 ` Vasily Averin
2021-09-13 10:10 ` Michal Hocko
2021-09-13 8:53 ` Michal Hocko
2021-09-13 10:35 ` Vasily Averin
2021-09-13 10:55 ` Michal Hocko
2021-09-14 10:01 ` Vasily Averin
2021-09-14 10:10 ` [PATCH memcg v2] " Vasily Averin
2021-09-16 12:55 ` Michal Hocko
2021-10-05 13:52 ` [PATCH memcg v3] " Vasily Averin
2021-10-05 14:55 ` 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=20211007125541.db0f3ff2bdbd8fa7dc1db03d@linux-foundation.org \
--to=akpm@linux-foundation.org \
--cc=cgroups@vger.kernel.org \
--cc=hannes@cmpxchg.org \
--cc=kernel@openvz.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=mhocko@kernel.org \
--cc=penguin-kernel@i-love.sakura.ne.jp \
--cc=vdavydov.dev@gmail.com \
--cc=vvs@virtuozzo.com \
/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).