From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752060AbeERGWS (ORCPT ); Fri, 18 May 2018 02:22:18 -0400 Received: from mx2.suse.de ([195.135.220.15]:59989 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751979AbeERGWR (ORCPT ); Fri, 18 May 2018 02:22:17 -0400 Date: Fri, 18 May 2018 08:22:13 +0200 From: Michal Hocko To: ufo19890607 Cc: akpm@linux-foundation.org, rientjes@google.com, kirill.shutemov@linux.intel.com, aarcange@redhat.com, penguin-kernel@I-love.SAKURA.ne.jp, guro@fb.com, yang.s@alibaba-inc.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org, yuzhoujian Subject: Re: [PATCH v2] Print the memcg's name when system-wide OOM happened Message-ID: <20180518062213.GA21711@dhcp22.suse.cz> References: <1526612834-8898-1-git-send-email-ufo19890607@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1526612834-8898-1-git-send-email-ufo19890607@gmail.com> User-Agent: Mutt/1.9.5 (2018-04-13) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri 18-05-18 04:07:14, ufo19890607 wrote: > From: yuzhoujian > > The dump_header does not print the memcg's name when the system > oom happened. So users cannot locate the certain container which > contains the task that has been killed by the oom killer. System > oom report will contain the memcg's name after this patch. It would be great to mention what you can the name for. > Changes since v1: > - replace adding mem_cgroup_print_oom_info with printing the memcg's > name only. > > Signed-off-by: yuzhoujian > --- > mm/oom_kill.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/mm/oom_kill.c b/mm/oom_kill.c > index 8ba6cb88cf58..b0abb5930232 100644 > --- a/mm/oom_kill.c > +++ b/mm/oom_kill.c > @@ -433,6 +433,9 @@ static void dump_header(struct oom_control *oc, struct task_struct *p) > if (is_memcg_oom(oc)) > mem_cgroup_print_oom_info(oc->memcg, p); > else { > + pr_info("Task in "); > + pr_cont_cgroup_path(task_cgroup(p, memory_cgrp_id)); > + pr_cont(" killed as a result of limit of "); > show_mem(SHOW_MEM_FILTER_NODES, oc->nodemask); > if (is_dump_unreclaim_slabs()) > dump_unreclaimable_slab(); I bet this doesn't compile with CONFIG_MEMCG=n. You either need to put these pr_info lines inside ifdef CONFIG_MEMCG or add helper. The later would reduce code duplication. -- Michal Hocko SUSE Labs