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 61F0BC433F5 for ; Wed, 22 Dec 2021 05:22:59 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 4DAA36B0072; Wed, 22 Dec 2021 00:22:58 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 48B196B0073; Wed, 22 Dec 2021 00:22:58 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 351FC6B0074; Wed, 22 Dec 2021 00:22:58 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0063.hostedemail.com [216.40.44.63]) by kanga.kvack.org (Postfix) with ESMTP id 238496B0072 for ; Wed, 22 Dec 2021 00:22:58 -0500 (EST) Received: from smtpin01.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id C00AA89B55 for ; Wed, 22 Dec 2021 05:22:57 +0000 (UTC) X-FDA: 78944285994.01.6E3DDEF Received: from mail-lj1-f169.google.com (mail-lj1-f169.google.com [209.85.208.169]) by imf23.hostedemail.com (Postfix) with ESMTP id 49F73140025 for ; Wed, 22 Dec 2021 05:22:50 +0000 (UTC) Received: by mail-lj1-f169.google.com with SMTP id a37so1830988ljq.13 for ; Tue, 21 Dec 2021 21:22:57 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=EHKD0zz0A17naK/vAZ2p+fvykUPrLdG+ZC/fRc2M8Rk=; b=RgtzbRu1yhWdXkg5X6WGFXigULqaULk18s9V4nZYjsURhJ5trBAGr2z4/USfLOjAay fu/VJ/8RERdZTu+MHkGuXlmjOsLTgtNizjOC3O0pnOcDxbx0CfPtrxABMO03fN+L5iug b+q8qwF3JuzTrU2U+qYxRBzHd4+fzJK5yH0jp1s3keJET0weBQ5VqGgPcs3l/1T+JETo t4C5oOhYg62xLdLOBk0uOWwX0PmHM11YWxkh30xMFCNi7frpdsZkjT8UjdIVXPmJe5g7 AveMIMyQZ756dicvMPvOvITZt4hbItsMcKj6bgPZcFFxC0mYzHyP1nj6QsuEsj6/tvkI qocA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=EHKD0zz0A17naK/vAZ2p+fvykUPrLdG+ZC/fRc2M8Rk=; b=0zYBmCWztNRvGbvCOCLTXtRrTRAm/bg1NTurzoZh6mQPMMsK9cnpk2DsSuPOb9LFlR 62hA5IUeu5mrpfhbkMZE59oDw3uvafCoOB/22V7l7JQeShsB3tz1hDVF4nlzxrM1qqaR TpmZUNguMQZU9qH/oy2NClJeHAYFKnM9yOi0B1kZJmZ8Eo+NsW4xtZnNOO0MpYJkE4z/ 1ORclmrKCNB5NMzOqaxmW+uEhauT9O+dxq4qDvT/TeUC1nlsPbklSlkyOnmhYapk2z7Q OZVdX0DEEIJ09mkuAj3SY3XW8wC7CRf8JfLQOjJqCIruV3hOJz6TxwIa3V46Cqx00zeS FH3g== X-Gm-Message-State: AOAM532VCm2HMEMKnoGk6JLWPZQeuVSG8J1k06lSMGlMqfx5r+QGLdZo hux9I7Tt8qFccw7iaIhkvHmpBRwiHu+qQX5IWwRtiQ== X-Google-Smtp-Source: ABdhPJxHLPnFrFhk4CFndt8TB4F2p8chAbA4z7J9E5E8t/rD5nNLWBr2GeHEkLtXMA025lY3mvreAmjg/X8R4nTlVuM= X-Received: by 2002:a2e:a314:: with SMTP id l20mr1186583lje.86.1640150575496; Tue, 21 Dec 2021 21:22:55 -0800 (PST) MIME-Version: 1.0 References: <20211221215336.1922823-1-shakeelb@google.com> In-Reply-To: From: Shakeel Butt Date: Tue, 21 Dec 2021 21:22:43 -0800 Message-ID: Subject: Re: [PATCH] memcg: add per-memcg vmalloc stat To: Muchun Song Cc: Johannes Weiner , Michal Hocko , Roman Gushchin , Andrew Morton , Linux Memory Management List , LKML Content-Type: text/plain; charset="UTF-8" X-Stat-Signature: 9sqxj8wgs7mqfmrjkiy8uda8wmajppw6 X-Rspamd-Server: rspam01 X-Rspamd-Queue-Id: 49F73140025 Authentication-Results: imf23.hostedemail.com; dkim=pass header.d=google.com header.s=20210112 header.b=RgtzbRu1; spf=pass (imf23.hostedemail.com: domain of shakeelb@google.com designates 209.85.208.169 as permitted sender) smtp.mailfrom=shakeelb@google.com; dmarc=pass (policy=reject) header.from=google.com X-HE-Tag: 1640150570-736601 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, Dec 21, 2021 at 8:15 PM Muchun Song wrote: > [...] > > +static inline void mod_memcg_page_state(struct page *page, > > + int idx, int val) > > +{ > > + struct mem_cgroup *memcg = page_memcg(page); > > + > > + if (!mem_cgroup_disabled() && memcg) > > + mod_memcg_state(memcg, idx, val); > > It's not safe to access @memcg throughout mod_memcg_state() for the > kmem charged through objcg infrastructure. It's supposed to be safe > to access @memcg under rcu read lock. Otherwise, it looks good to > me. Indeed you are right. v2 coming.