From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf0-f199.google.com (mail-pf0-f199.google.com [209.85.192.199]) by kanga.kvack.org (Postfix) with ESMTP id 7F8DC6B05F4 for ; Thu, 10 May 2018 07:41:52 -0400 (EDT) Received: by mail-pf0-f199.google.com with SMTP id w7-v6so1038934pfd.9 for ; Thu, 10 May 2018 04:41:52 -0700 (PDT) Received: from mx2.suse.de (mx2.suse.de. [195.135.220.15]) by mx.google.com with ESMTPS id w9-v6si619166plp.389.2018.05.10.04.41.49 for (version=TLS1 cipher=AES128-SHA bits=128/128); Thu, 10 May 2018 04:41:50 -0700 (PDT) Date: Thu, 10 May 2018 13:41:47 +0200 From: Michal Hocko Subject: Re: [PATCH v2] mm: fix oom_kill event handling Message-ID: <20180510114147.GB5325@dhcp22.suse.cz> References: <20180508124637.29984-1-guro@fb.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180508124637.29984-1-guro@fb.com> Sender: owner-linux-mm@kvack.org List-ID: To: Roman Gushchin Cc: kernel-team@fb.com, Johannes Weiner , Vladimir Davydov , Andrew Morton , Konstantin Khlebnikov , linux-kernel@vger.kernel.org, cgroups@vger.kernel.org, linux-mm@kvack.org On Tue 08-05-18 13:46:37, Roman Gushchin wrote: > Commit e27be240df53 ("mm: memcg: make sure memory.events is > uptodate when waking pollers") converted most of memcg event > counters to per-memcg atomics, which made them less confusing > for a user. The "oom_kill" counter remained untouched, so now > it behaves differently than other counters (including "oom"). > This adds nothing but confusion. > > Let's fix this by adding the MEMCG_OOM_KILL event, and follow > the MEMCG_OOM approach. This also removes a hack from > count_memcg_event_mm(), introduced earlier specially for the > OOM_KILL counter. I agree that the current OOM_KILL is confusing. But do we really need another memcg_memory_event_mm helper used for only one counter rather than reuse memcg_memory_event. __oom_kill_process doesn't have the memcg but nothing should really prevent us from adding the context (oom_control) there, no? [...] -- Michal Hocko SUSE Labs