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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A4E9BC433F5 for ; Thu, 11 Nov 2021 02:59:36 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 289A9610A2 for ; Thu, 11 Nov 2021 02:59:36 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 289A9610A2 Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=google.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kvack.org Received: by kanga.kvack.org (Postfix) id 84C906B00BA; Wed, 10 Nov 2021 21:59:35 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 7FBE16B00BC; Wed, 10 Nov 2021 21:59:35 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 710FB6B00BD; Wed, 10 Nov 2021 21:59:35 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0189.hostedemail.com [216.40.44.189]) by kanga.kvack.org (Postfix) with ESMTP id 62A716B00BA for ; Wed, 10 Nov 2021 21:59:35 -0500 (EST) Received: from smtpin29.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id 1B000184B40D0 for ; Thu, 11 Nov 2021 02:59:35 +0000 (UTC) X-FDA: 78795143910.29.C3D31EC Received: from mail-lf1-f53.google.com (mail-lf1-f53.google.com [209.85.167.53]) by imf07.hostedemail.com (Postfix) with ESMTP id BE7CA10004D0 for ; Thu, 11 Nov 2021 02:59:34 +0000 (UTC) Received: by mail-lf1-f53.google.com with SMTP id b40so10729132lfv.10 for ; Wed, 10 Nov 2021 18:59:34 -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=a6bvux9h4Tr+KwqfPK/pFOv6v4cxO/N2b3R9XEEhqfA=; b=KDQJS33Ko67BZRHhm8SAexUqACFOdnsqgxdgYVDPFDQC+8MvPteA2hm9UbIRtTJkQh Oc+2RR8+ufsH87ZEI5srk3pL2ZDjtvw0rDIQLu/NPMC1JcMH/jjeuIkZ7eFejmALs6zZ BEpvk/xRtgnnUuT32K8Dr7rcVhceHBuDl0RKJpeBPGdV22wUhEAQv7wI5qIQ9WxNUQF1 xTCOn7UfKj3BSiMmgUnDA/5eUr7XYsLbWpAmWuPz7w6Z6mk4U/QUn/nfDwVvko29h7l5 MeOS75sIYUHTRgy3ZVaPt5+Jixb+UH/oorFRbabxocfXzmryICvQWLbhdQ10STL+d3nD z4AQ== 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=a6bvux9h4Tr+KwqfPK/pFOv6v4cxO/N2b3R9XEEhqfA=; b=kXhZDUM51efFzRU37mMgnKShncAqhIJ49EbOMgONLSu2d5lqJoEcviUcjvnZPEvrtp b5iW6ZRYc0vg+p+YpMcEg5m467Y2sFkq38pkg4aZLM/P9lUDHbQXMpwy0kQ2W1u9Vo8Y BW0vJvSb295zeiacBqNbVd3UFAX4P4Q7Qx+Cx6ygNuARSlhEy9cVkdIzV4JzKyA/1GIy 6HlX4bGImDIoBvxgPZX8TOYau7fygvu4+BGv+RFau3JeBETFekC32RvNE0N7nPwTJBmI 8J5eQNyMEUJTrtGsCuEaFRAkShX1n9RzNq51+nXaFI5qDjLsVTQjUqC4kFJI8ACdkxy5 t6Mw== X-Gm-Message-State: AOAM530bqOGMA4/a/Y+OS1fI0TUl0M5IpjsTpbpHXQyvfAzmWekmMOA4 iWnhnowzZI0HQc3gx0/e2u4xL3FWizz5LOevv8763Q== X-Google-Smtp-Source: ABdhPJxzhDNEDPMkTAH3kZ7hEGWYTrqJQHm6P1MmxF31i/OnkWBxMRzmcgwDgpnaj6QeOUpbdkvavT2rep1HOK4mom0= X-Received: by 2002:a05:6512:31c3:: with SMTP id j3mr3746996lfe.8.1636599572953; Wed, 10 Nov 2021 18:59:32 -0800 (PST) MIME-Version: 1.0 References: <20211111015037.4092956-1-almasrymina@google.com> In-Reply-To: From: Shakeel Butt Date: Wed, 10 Nov 2021 18:59:21 -0800 Message-ID: Subject: Re: [PATCH v6] hugetlb: Add hugetlb.*.numa_stat file To: Muchun Song Cc: Mina Almasry , Mike Kravetz , Andrew Morton , Shuah Khan , Miaohe Lin , Oscar Salvador , Michal Hocko , David Rientjes , Jue Wang , Yang Yao , Joanna Li , Cannon Matthews , Linux Memory Management List , LKML Content-Type: text/plain; charset="UTF-8" X-Rspamd-Server: rspam02 X-Rspamd-Queue-Id: BE7CA10004D0 X-Stat-Signature: 5rht9crdwr7t33nuyxecx87z6ohiikrq Authentication-Results: imf07.hostedemail.com; dkim=pass header.d=google.com header.s=20210112 header.b=KDQJS33K; spf=pass (imf07.hostedemail.com: domain of shakeelb@google.com designates 209.85.167.53 as permitted sender) smtp.mailfrom=shakeelb@google.com; dmarc=pass (policy=reject) header.from=google.com X-HE-Tag: 1636599574-65883 X-Bogosity: Ham, tests=bogofilter, spamicity=0.053454, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Wed, Nov 10, 2021 at 6:36 PM Muchun Song wrote: > [...] > > +struct hugetlb_cgroup_per_node { > > + /* hugetlb usage in pages over all hstates. */ > > + atomic_long_t usage[HUGE_MAX_HSTATE]; > > Why do you use atomic? IIUC, 'usage' is always > increased/decreased under hugetlb_lock except > hugetlb_cgroup_read_numa_stat() which is always > reading it. So I think WRITE_ONCE/READ_ONCE > is enough. Oh this is me misguiding Mina, sorry about that. Yes, READ_ONCE() should be good enough in hugetlb_cgroup_read_numa_stat().