From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pg0-f69.google.com (mail-pg0-f69.google.com [74.125.83.69]) by kanga.kvack.org (Postfix) with ESMTP id 212156B0261 for ; Tue, 3 Oct 2017 14:06:42 -0400 (EDT) Received: by mail-pg0-f69.google.com with SMTP id i195so17268897pgd.2 for ; Tue, 03 Oct 2017 11:06:42 -0700 (PDT) Received: from out4441.biz.mail.alibaba.com (out4441.biz.mail.alibaba.com. [47.88.44.41]) by mx.google.com with ESMTPS id n59si10946399plb.48.2017.10.03.11.06.39 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 03 Oct 2017 11:06:40 -0700 (PDT) From: "Yang Shi" Subject: [PATCH 0/3 v8] oom: capture unreclaimable slab info in oom message Date: Wed, 04 Oct 2017 02:06:14 +0800 Message-Id: <1507053977-116952-1-git-send-email-yang.s@alibaba-inc.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: owner-linux-mm@kvack.org List-ID: To: cl@linux.com, penberg@kernel.org, rientjes@google.com, iamjoonsoo.kim@lge.com, akpm@linux-foundation.org, mhocko@kernel.org Cc: Yang Shi , linux-mm@kvack.org, linux-kernel@vger.kernel.org Recently we ran into a oom issue, kernel panic due to no killable process. The dmesg shows huge unreclaimable slabs used almost 100% memory, but kdump doesn't capture vmcore due to some reason. So, it may sound better to capture unreclaimable slab info in oom message when kernel panic to aid trouble shooting and cover the corner case. Since kernel already panic, so capturing more information sounds worthy and doesn't bother normal oom killer. With the patchset, tools/vm/slabinfo has a new option, "-U", to show unreclaimable slab only. And, oom will print all non zero (num_objs * size != 0) unreclaimable slabs in oom killer message. For details, please see the commit log for each commit. Changelog v8 a??> 9: * Adopted Tetsuoa??s suggestion to protect global slab list traverse with mutex_trylock() to prevent from sleeping. Without the mutex acquired unreclaimable slbas will not be dumped. * Adopted the suggestion from Christoph to dump CONFIG_SLABINFO since it is pointless to keep it. * Rebased to 4.13-rc3 Changelog v7 a??> v8: * Adopted Michala??s suggestion to dump unreclaim slab info when unreclaimable slabs amount > total user memory. Not only in oom panic path. Changelog v6 -> v7: * Added unreclaim_slabs_oom_ratio proc knob, unreclaimable slabs info will be dumped when unreclaimable slabs amount : all user memory > the ratio Changelog v5 a??> v6: * Fixed a checkpatch.pl warning for patch #2 Changelog v4 a??> v5: * Solved the comments from David * Build test SLABINFO = n Changelog v3 a??> v4: * Solved the comments from David * Added Davida??s Acked-by in patch 1 Changelog v2 a??> v3: * Show used size and total size of each kmem cache per Davida??s comment Changelog v1 a??> v2: * Removed the original patch 1 (a??mm: slab: output reclaimable flag in /proc/slabinfoa??) since Christoph suggested it might break the compatibility and /proc/slabinfo is legacy * Added Christopha??s Acked-by * Removed acquiring slab_mutex per Tetsuoa??s comment Yang Shi (3): tools: slabinfo: add "-U" option to show unreclaimable slabs only mm: slabinfo: dump CONFIG_SLABINFO mm: oom: show unreclaimable slab info when unreclaimable slabs > user memory init/Kconfig | 6 ------ mm/memcontrol.c | 2 -- mm/oom_kill.c | 22 ++++++++++++++++++++++ mm/slab.c | 2 -- mm/slab.h | 2 ++ mm/slab_common.c | 35 ++++++++++++++++++++++++++++++++--- mm/slub.c | 2 -- tools/vm/slabinfo.c | 11 ++++++++++- 8 files changed, 66 insertions(+), 16 deletions(-) -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org