From patchwork Thu Apr 29 18:54:57 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Tim Gardner X-Patchwork-Id: 1471826 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=none (no SPF record) smtp.mailfrom=lists.ubuntu.com (client-ip=91.189.94.19; helo=huckleberry.canonical.com; envelope-from=kernel-team-bounces@lists.ubuntu.com; receiver=) Received: from huckleberry.canonical.com (huckleberry.canonical.com [91.189.94.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 4FWPp33vdQz9t1s; Fri, 30 Apr 2021 04:55:23 +1000 (AEST) Received: from localhost ([127.0.0.1] helo=huckleberry.canonical.com) by huckleberry.canonical.com with esmtp (Exim 4.86_2) (envelope-from ) id 1lcBol-0008JW-RP; Thu, 29 Apr 2021 18:55:19 +0000 Received: from youngberry.canonical.com ([91.189.89.112]) by huckleberry.canonical.com with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.86_2) (envelope-from ) id 1lcBoZ-0008CL-QO for kernel-team@lists.ubuntu.com; Thu, 29 Apr 2021 18:55:07 +0000 Received: from mail-pg1-f200.google.com ([209.85.215.200]) by youngberry.canonical.com with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.86_2) (envelope-from ) id 1lcBoZ-0002vu-DV for kernel-team@lists.ubuntu.com; Thu, 29 Apr 2021 18:55:07 +0000 Received: by mail-pg1-f200.google.com with SMTP id j19-20020a63fc130000b029020f623342e0so830641pgi.10 for ; Thu, 29 Apr 2021 11:55:07 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=vMFwDO6flp1u2c64QCbXHa5v/LEzG0OWsuVsR1PLSCg=; b=KjtTKqFXqChViGBK2+SPzAjgSW9mM70uKPEdLVjSj0HrSWcRzlsN4Vr34VSI9LPT5R pvUNFxztSHoiN6zpdAUoBUw6HkguKoAu4Bc4eH8mFz6jks4zRTf8uI1D27p5PNkD9Wvg kphaxe/6E8j21y4mcTRu5kpaX4v+61EeUHopa/eD09/viuifJfzG8p7imbmrGi3ylJz7 OCb4yPSs2kpwU9vBC84uYhGNpkFfsFSFdan1Jdvlp5w85EL27olvE8rEIGjQq4RRpNNt kbf1GkXhjOZutEUqGm2qsUQXlgSTfALOCW+9Li+y2RXHHGeYqoRQCCZS6k3uu94g9Rc0 lZRw== X-Gm-Message-State: AOAM533kChMiWr4TE+BbOCgXpA+skHUXumciQ3zvpWRKExdSEXU/0Lju 4sv1DGbUoXZMmhAkAskJZyiVr7piTvORUWON9m3hbbmjBFCIyHcD/VJu4F746Ezdq6dZDLA9N1f 2QSVTEo9mzShoJyc3iMC0QjVFzOVuIsUhQ4gyN1PRwQ== X-Received: by 2002:a65:418a:: with SMTP id a10mr1063893pgq.307.1619722505624; Thu, 29 Apr 2021 11:55:05 -0700 (PDT) X-Google-Smtp-Source: ABdhPJzlukj1Pt73UjoPa8xD/0P6lRpSwz59wfa/Hb0ncHYXFqOuSdyHaz7EO4hSM3y65Rsvjt1ssw== X-Received: by 2002:a65:418a:: with SMTP id a10mr1063879pgq.307.1619722505394; Thu, 29 Apr 2021 11:55:05 -0700 (PDT) Received: from localhost.localdomain ([69.163.84.166]) by smtp.gmail.com with ESMTPSA id e9sm608999pgk.69.2021.04.29.11.55.04 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 29 Apr 2021 11:55:04 -0700 (PDT) From: Tim Gardner To: kernel-team@lists.ubuntu.com Subject: [PATCH 4/4] mm: fix oom_kill event handling Date: Thu, 29 Apr 2021 12:54:57 -0600 Message-Id: <20210429185457.23381-5-tim.gardner@canonical.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20210429185457.23381-1-tim.gardner@canonical.com> References: <20210429185457.23381-1-tim.gardner@canonical.com> X-BeenThere: kernel-team@lists.ubuntu.com X-Mailman-Version: 2.1.20 Precedence: list List-Id: Kernel team discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: kernel-team-bounces@lists.ubuntu.com Sender: "kernel-team" From: Roman Gushchin BugLink: https://bugs.launchpad.net/bugs/1926081 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 (backported from commit fe6bdfc8e1e131720abbe77a2eb990c94c9024cb) [rtg - context adjustments] Signed-off-by: Tim Gardner Acked-by: Krzysztof Kozlowski --- 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 c7876eadd206d..b5cd86e320ff3 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 1161dd0ba3ff4..d9ce3263d97fb 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -3666,7 +3666,8 @@ 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; } @@ -5338,7 +5339,8 @@ 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 6999cf9c99bcb..187e385683cb9 100644 --- a/mm/oom_kill.c +++ b/mm/oom_kill.c @@ -927,7 +927,7 @@ 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