From patchwork Sat Nov 2 15:16:33 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Konstantin Khlebnikov X-Patchwork-Id: 11224145 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id BF6751709 for ; Sat, 2 Nov 2019 15:16:39 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 8AECA21906 for ; Sat, 2 Nov 2019 15:16:39 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=yandex-team.ru header.i=@yandex-team.ru header.b="X9dFktO7" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 8AECA21906 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=yandex-team.ru Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 9D7326B0005; Sat, 2 Nov 2019 11:16:38 -0400 (EDT) Delivered-To: linux-mm-outgoing@kvack.org Received: by kanga.kvack.org (Postfix, from userid 40) id 987896B0006; Sat, 2 Nov 2019 11:16:38 -0400 (EDT) X-Original-To: int-list-linux-mm@kvack.org X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 8C3926B0007; Sat, 2 Nov 2019 11:16:38 -0400 (EDT) X-Original-To: linux-mm@kvack.org X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0235.hostedemail.com [216.40.44.235]) by kanga.kvack.org (Postfix) with ESMTP id 74FC86B0005 for ; Sat, 2 Nov 2019 11:16:38 -0400 (EDT) Received: from smtpin25.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with SMTP id 31F67181AC9C6 for ; Sat, 2 Nov 2019 15:16:38 +0000 (UTC) X-FDA: 76111689276.25.root46_7405bf22ec74e X-Spam-Summary: 2,0,0,f4d0a3e8bc6bbf81,d41d8cd98f00b204,khlebnikov@yandex-team.ru,::akpm@linux-foundation.org:linux-kernel@vger.kernel.org:cgroups@vger.kernel.org:mhocko@suse.com,RULES_HIT:41:152:355:379:800:960:973:988:989:1260:1277:1311:1313:1314:1345:1437:1515:1516:1518:1534:1541:1593:1594:1711:1730:1747:1777:1792:2198:2199:2393:2553:2559:2562:2693:2731:3138:3139:3140:3141:3142:3352:3865:3867:3868:3870:3871:3872:4250:5007:6119:6261:6653:9207:10004:10400:11026:11232:11658:11914:12043:12297:12517:12519:12555:12679:12760:13069:13311:13357:14096:14097:14181:14394:14687:14721:14922:21080:21451:21627:21795:30051:30054:30070:30090,0,RBL:77.88.29.217:@yandex-team.ru:.lbl8.mailshell.net-62.2.3.100 66.100.201.201,CacheIP:none,Bayesian:0.5,0.5,0.5,Netcheck:none,DomainCache:0,MSF:not bulk,SPF:fp,MSBL:0,DNSBL:neutral,Custom_rules:0:0:0,LFtime:140,LUA_SUMMARY:none X-HE-Tag: root46_7405bf22ec74e X-Filterd-Recvd-Size: 3401 Received: from forwardcorp1p.mail.yandex.net (forwardcorp1p.mail.yandex.net [77.88.29.217]) by imf20.hostedemail.com (Postfix) with ESMTP for ; Sat, 2 Nov 2019 15:16:37 +0000 (UTC) Received: from mxbackcorp1o.mail.yandex.net (mxbackcorp1o.mail.yandex.net [IPv6:2a02:6b8:0:1a2d::301]) by forwardcorp1p.mail.yandex.net (Yandex) with ESMTP id 941382E099D; Sat, 2 Nov 2019 18:16:34 +0300 (MSK) Received: from vla1-5826f599457c.qloud-c.yandex.net (vla1-5826f599457c.qloud-c.yandex.net [2a02:6b8:c0d:35a1:0:640:5826:f599]) by mxbackcorp1o.mail.yandex.net (nwsmtp/Yandex) with ESMTP id UjI6F08SWn-GXjiaB0J; Sat, 02 Nov 2019 18:16:34 +0300 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=yandex-team.ru; s=default; t=1572707794; bh=AR0posdeGGjRMOUjYp9dgJq5OCpwQBAAcmepPzGDKWg=; h=Message-ID:Date:To:From:Subject:Cc; b=X9dFktO77Na/G0mtC2+xSzpD1cMLgWOkM1P9fpb+ypv5Obc9xW91WTB8Mc1xm15fI f+vjegUUhK0i7hnoRfJ+Na/UVVXYuRet+Jx2AzVkMEQdB23FUCLveNYbe34Rajfqob WnSYBjjQfRvF4wy/a3HK7oM0Cf0Nz8wpJRNk4zps= Authentication-Results: mxbackcorp1o.mail.yandex.net; dkim=pass header.i=@yandex-team.ru Received: from dynamic-red.dhcp.yndx.net (dynamic-red.dhcp.yndx.net [2a02:6b8:0:40c:8554:53c0:3d75:2e8a]) by vla1-5826f599457c.qloud-c.yandex.net (nwsmtp/Yandex) with ESMTPSA id kxXcRS1iUB-GXVOVCeE; Sat, 02 Nov 2019 18:16:33 +0300 (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (Client certificate not present) Subject: [PATCH] mm/memcontrol: update documentation about invoking oom killer From: Konstantin Khlebnikov To: linux-mm@kvack.org, Andrew Morton , linux-kernel@vger.kernel.org Cc: cgroups@vger.kernel.org, Michal Hocko Date: Sat, 02 Nov 2019 18:16:33 +0300 Message-ID: <157270779336.1961.6528158720593572480.stgit@buzz> User-Agent: StGit/0.17.1-dirty MIME-Version: 1.0 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: Since commit 29ef680ae7c2 ("memcg, oom: move out_of_memory back to the charge path") memcg invokes oom killer not only for user page-faults. This means 0-order allocation will either succeed or task get killed. Fixes: 8e675f7af507 ("mm/oom_kill: count global and memory cgroup oom kills") Signed-off-by: Konstantin Khlebnikov --- Documentation/admin-guide/cgroup-v2.rst | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/Documentation/admin-guide/cgroup-v2.rst b/Documentation/admin-guide/cgroup-v2.rst index 5361ebec3361..eb47815e137b 100644 --- a/Documentation/admin-guide/cgroup-v2.rst +++ b/Documentation/admin-guide/cgroup-v2.rst @@ -1219,8 +1219,13 @@ PAGE_SIZE multiple when read back. Failed allocation in its turn could be returned into userspace as -ENOMEM or silently ignored in cases like - disk readahead. For now OOM in memory cgroup kills - tasks iff shortage has happened inside page fault. + disk readahead. + + Before 4.19 OOM in memory cgroup killed tasks iff + shortage has happened inside page fault, random + syscall may fail with ENOMEM or EFAULT. Since 4.19 + failed memory cgroup allocation invokes oom killer and + keeps retrying until it succeeds. This event is not raised if the OOM killer is not considered as an option, e.g. for failed high-order