From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-18.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id DADFFC433B4 for ; Mon, 5 Apr 2021 09:00:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id BC1BD61394 for ; Mon, 5 Apr 2021 09:00:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236641AbhDEJA4 (ORCPT ); Mon, 5 Apr 2021 05:00:56 -0400 Received: from mail.kernel.org ([198.145.29.99]:41692 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237066AbhDEJAM (ORCPT ); Mon, 5 Apr 2021 05:00:12 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 888E7613A5; Mon, 5 Apr 2021 09:00:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1617613207; bh=MlyoqGQDdBgFgvy9WiTiNYHqEhDIjQiHUhgVS/YCSTg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=gRPSfNx4UZWWkKmekycLeLWf4LnqDOcCpF9kWIBAvz81Ny1Vjv3VfJ4BMg9LDCfMW ukclBOoklmzE5W5aMahy4IAVroS38z/FTAtSujS+vl3IYdmsyow05XaPvHzfJDGfqG w9qgpbRahaOcUdjsl225xHbhGEVZa9AlAZE8Dfv8= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Roman Gushchin , Konstantin Khlebnikov , Johannes Weiner , Michal Hocko , Vladimir Davydov , Andrew Morton , Linus Torvalds , Frank van der Linden , Sasha Levin Subject: [PATCH 4.14 35/52] mm: fix oom_kill event handling Date: Mon, 5 Apr 2021 10:54:01 +0200 Message-Id: <20210405085023.135458367@linuxfoundation.org> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210405085021.996963957@linuxfoundation.org> References: <20210405085021.996963957@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Roman Gushchin commit fe6bdfc8e1e131720abbe77a2eb990c94c9024cb upstream. 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. [akpm@linux-foundation.org: fix for droppage of memcg-replace-mm-owner-with-mm-memcg.patch] Link: http://lkml.kernel.org/r/20180508124637.29984-1-guro@fb.com Signed-off-by: Roman Gushchin Acked-by: Konstantin Khlebnikov Acked-by: Johannes Weiner Acked-by: Michal Hocko Cc: Vladimir Davydov Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds [fllinden@amazon.com: backport to 4.14, minor contextual changes] Signed-off-by: Frank van der Linden Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin --- include/linux/memcontrol.h | 26 ++++++++++++++++++++++---- mm/memcontrol.c | 6 ++++-- mm/oom_kill.c | 2 +- 3 files changed, 27 insertions(+), 7 deletions(-) diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h index c7876eadd206..b5cd86e320ff 100644 --- a/include/linux/memcontrol.h +++ b/include/linux/memcontrol.h @@ -53,6 +53,7 @@ enum memcg_memory_event { MEMCG_HIGH, MEMCG_MAX, MEMCG_OOM, + MEMCG_OOM_KILL, MEMCG_NR_MEMORY_EVENTS, }; @@ -706,11 +707,8 @@ static inline void count_memcg_event_mm(struct mm_struct *mm, rcu_read_lock(); memcg = mem_cgroup_from_task(rcu_dereference(mm->owner)); - if (likely(memcg)) { + if (likely(memcg)) count_memcg_events(memcg, idx, 1); - if (idx == OOM_KILL) - cgroup_file_notify(&memcg->events_file); - } rcu_read_unlock(); } @@ -721,6 +719,21 @@ static inline void memcg_memory_event(struct mem_cgroup *memcg, cgroup_file_notify(&memcg->events_file); } +static inline void memcg_memory_event_mm(struct mm_struct *mm, + enum memcg_memory_event event) +{ + struct mem_cgroup *memcg; + + if (mem_cgroup_disabled()) + return; + + rcu_read_lock(); + memcg = mem_cgroup_from_task(rcu_dereference(mm->owner)); + if (likely(memcg)) + memcg_memory_event(memcg, event); + rcu_read_unlock(); +} + #ifdef CONFIG_TRANSPARENT_HUGEPAGE void mem_cgroup_split_huge_fixup(struct page *head); #endif @@ -742,6 +755,11 @@ static inline void memcg_memory_event(struct mem_cgroup *memcg, { } +static inline void memcg_memory_event_mm(struct mm_struct *mm, + enum memcg_memory_event event) +{ +} + static inline bool mem_cgroup_low(struct mem_cgroup *root, struct mem_cgroup *memcg) { diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 31972189a827..ef6d996a920a 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -3648,7 +3648,8 @@ static int mem_cgroup_oom_control_read(struct seq_file *sf, void *v) seq_printf(sf, "oom_kill_disable %d\n", memcg->oom_kill_disable); seq_printf(sf, "under_oom %d\n", (bool)memcg->under_oom); - seq_printf(sf, "oom_kill %lu\n", memcg_sum_events(memcg, OOM_KILL)); + seq_printf(sf, "oom_kill %lu\n", + atomic_long_read(&memcg->memory_events[MEMCG_OOM_KILL])); return 0; } @@ -5320,7 +5321,8 @@ static int memory_events_show(struct seq_file *m, void *v) atomic_long_read(&memcg->memory_events[MEMCG_MAX])); seq_printf(m, "oom %lu\n", atomic_long_read(&memcg->memory_events[MEMCG_OOM])); - seq_printf(m, "oom_kill %lu\n", memcg_sum_events(memcg, OOM_KILL)); + seq_printf(m, "oom_kill %lu\n", + atomic_long_read(&memcg->memory_events[MEMCG_OOM_KILL])); return 0; } diff --git a/mm/oom_kill.c b/mm/oom_kill.c index 6482d743c5c8..6f1bed211122 100644 --- a/mm/oom_kill.c +++ b/mm/oom_kill.c @@ -917,7 +917,7 @@ static void oom_kill_process(struct oom_control *oc, const char *message) /* Raise event before sending signal: task reaper must see this */ count_vm_event(OOM_KILL); - count_memcg_event_mm(mm, OOM_KILL); + memcg_memory_event_mm(mm, MEMCG_OOM_KILL); /* * We should send SIGKILL before granting access to memory reserves -- 2.30.2