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 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5BB9EECAAD3 for ; Mon, 19 Sep 2022 21:36:28 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 6C45D940007; Mon, 19 Sep 2022 17:36:27 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 673F46B0072; Mon, 19 Sep 2022 17:36:27 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 5141A940007; Mon, 19 Sep 2022 17:36:27 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0011.hostedemail.com [216.40.44.11]) by kanga.kvack.org (Postfix) with ESMTP id 403386B0071 for ; Mon, 19 Sep 2022 17:36:27 -0400 (EDT) Received: from smtpin02.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay02.hostedemail.com (Postfix) with ESMTP id E8E9C120E80 for ; Mon, 19 Sep 2022 21:36:26 +0000 (UTC) X-FDA: 79930143972.02.AED3EAB Received: from mail-pg1-f202.google.com (mail-pg1-f202.google.com [209.85.215.202]) by imf25.hostedemail.com (Postfix) with ESMTP id 7F684A00D4 for ; Mon, 19 Sep 2022 21:36:26 +0000 (UTC) Received: by mail-pg1-f202.google.com with SMTP id 135-20020a63018d000000b00430673f7922so298984pgb.6 for ; Mon, 19 Sep 2022 14:36:26 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date; bh=gBPDRnXdyvF4xAXr245jZgfFcKRBxlvo8nsBRpPChFM=; b=pBQdFlYTW5SMJZLEMS2PIeY/jXnxQHmBdVPB0G13hsQ/jjd473V1RsISyxaNwQYjyP yH1LP0v5pq5LDRQLhpdkRO31sgmsuTaBoWRWpfl3oJObc2DyxrjOIJQRM78202UbhSDs I3YXeiX+4M9mVmC/jNaFEUhrogAJuDu88LJDMqkZifaAjpi+hYvR1xpnjM+HACqJ94bB LajxRGIq9aCsw8DTPeTOjXxhSvXNlH3t+YvGLSTEWAQ4/W3reGAiQWXWsg7YBT9/1i1f x7kIHKYQ/xdvouPjm2aKVRXkjRJtsiVBtIUblxJ9idoqr+i9hG1fedynPAQfkv10QNB9 TPhQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date; bh=gBPDRnXdyvF4xAXr245jZgfFcKRBxlvo8nsBRpPChFM=; b=niJnsaZQ0Zu1pWAS+rAScrmEy/0zmF0ZPeENVDYgbBAFvD5PjFz/v+Fv7HPzI/8grU GVK42PI6lqNHNLoMh920zFsC/ndFoTXJ+MpXICrLnbWSxFtfUokwR1MSNbKVSqNRoDfY dFE4IAk6GiKYjG5DQWVJ4iwCyWWKxYAheJWPdpH3C2lX3ql3rQjcdi8rXGMh9cyBqqjs Ha5kQwbNZKALumFFL7tAPX9dNctEnavM/OySXdiXZ9lU5urzigJE/mjP7HJN/EstJBgR 1CbpFQxcT82rA8HP5nFDNwlRhJNT668MWmSwPf5tyZ6LokGcetr1jEfdYks9Gr+sxcZ3 QNTw== X-Gm-Message-State: ACrzQf3loNKi8Ce8Q/0dSIlhRdEBV3ghdXx8APkTEV1cDutJh3/aUSDk uFhKzml3ONaCLHJ/QeydvjgGrzTkBCdKig== X-Google-Smtp-Source: AMsMyM5N8FWtYCLqNF0zfkdeNsEsbGZbL/ZlbqHTPultDwLR5KPcpZgvQuO9hx4F8/FG9yKpgr9DjPIcxlzz6A== X-Received: from shakeelb.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:262e]) (user=shakeelb job=sendgmr) by 2002:a17:90b:254a:b0:200:53f:891d with SMTP id nw10-20020a17090b254a00b00200053f891dmr246179pjb.168.1663623385293; Mon, 19 Sep 2022 14:36:25 -0700 (PDT) Date: Mon, 19 Sep 2022 21:36:22 +0000 In-Reply-To: <20220919180634.45958-2-ryncsn@gmail.com> Mime-Version: 1.0 References: <20220919180634.45958-1-ryncsn@gmail.com> <20220919180634.45958-2-ryncsn@gmail.com> Message-ID: <20220919213622.s3w2v2q7ktvbrpha@google.com> Subject: Re: [PATCH v2 1/2] mm: memcontrol: use memcg_kmem_enabled in count_objcg_event From: Shakeel Butt To: Kairui Song Cc: cgroups@vger.kernel.org, linux-mm@kvack.org, Johannes Weiner , Michal Hocko , Roman Gushchin , Muchun Song , Andrew Morton , linux-kernel@vger.kernel.org Content-Type: text/plain; charset="us-ascii" ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1663623386; a=rsa-sha256; cv=none; b=M9Yf2Hn9u0GHcjclTMJy/gjrllvXesNYjXrJIE5m58XpGe7kwMN6JaGGWhDwJTybZxF7wk nTh2mBAl6udzpqpS2HDq/rsooakhc6u2XcsKdpqGSdtlC/aTIhuLGMWdA1bntUdCt3dQP0 f11ms6+p8c16IldU+hcWg8uSa1pK644= ARC-Authentication-Results: i=1; imf25.hostedemail.com; dkim=pass header.d=google.com header.s=20210112 header.b=pBQdFlYT; spf=pass (imf25.hostedemail.com: domain of 32eAoYwgKCF4OD6GAAH7CKKCHA.8KIHEJQT-IIGR68G.KNC@flex--shakeelb.bounces.google.com designates 209.85.215.202 as permitted sender) smtp.mailfrom=32eAoYwgKCF4OD6GAAH7CKKCHA.8KIHEJQT-IIGR68G.KNC@flex--shakeelb.bounces.google.com; dmarc=pass (policy=reject) header.from=google.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1663623386; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=gBPDRnXdyvF4xAXr245jZgfFcKRBxlvo8nsBRpPChFM=; b=e2U6gN8fgvCeTZBXVG17fNBajBh6yxteS/5LQt8PTQ+k5MQy+5GhKzOMSmyRRncE8AlBot ogzeKoMpkVFGLkUhjvMEL/EEoArosMYJtBVxjHqkBoBGF/h7oVx9iuq/xwV3jQupKU5Sk0 3cCgs/OQbG1anxMTqaW+07UtbIfhfBc= X-Stat-Signature: nrn7779efspj9a15y8wgdy7jaisrt1mt X-Rspam-User: Authentication-Results: imf25.hostedemail.com; dkim=pass header.d=google.com header.s=20210112 header.b=pBQdFlYT; spf=pass (imf25.hostedemail.com: domain of 32eAoYwgKCF4OD6GAAH7CKKCHA.8KIHEJQT-IIGR68G.KNC@flex--shakeelb.bounces.google.com designates 209.85.215.202 as permitted sender) smtp.mailfrom=32eAoYwgKCF4OD6GAAH7CKKCHA.8KIHEJQT-IIGR68G.KNC@flex--shakeelb.bounces.google.com; dmarc=pass (policy=reject) header.from=google.com X-Rspamd-Server: rspam01 X-Rspamd-Queue-Id: 7F684A00D4 X-HE-Tag: 1663623386-904613 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Tue, Sep 20, 2022 at 02:06:33AM +0800, Kairui Song wrote: > From: Kairui Song > > There are currently two helpers for checking if cgroup kmem > accounting is enabled: > > - mem_cgroup_kmem_disabled > - memcg_kmem_enabled > > mem_cgroup_kmem_disabled is a simple helper that returns true > if cgroup.memory=nokmem is specified, otherwise returns false. > > memcg_kmem_enabled is a bit different, it returns true if > cgroup.memory=nokmem is not specified and there was at least one > non-root memory control enabled cgroup ever created. This help improve > performance when kmem accounting was not actually activated. And it's > optimized with static branch. > > The usage of mem_cgroup_kmem_disabled is for sub-systems that need to > preallocate data for kmem accounting since they could be initialized > before kmem accounting is activated. But count_objcg_event doesn't > need that, so using memcg_kmem_enabled is better here. > > Signed-off-by: Kairui Song Acked-by: Shakeel Butt