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=-2.5 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS, URIBL_BLOCKED,USER_AGENT_MUTT autolearn=ham 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 71F21C43381 for ; Thu, 28 Mar 2019 14:05:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3C0C421773 for ; Thu, 28 Mar 2019 14:05:40 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=cmpxchg-org.20150623.gappssmtp.com header.i=@cmpxchg-org.20150623.gappssmtp.com header.b="0Cj5ef94" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726669AbfC1OFi (ORCPT ); Thu, 28 Mar 2019 10:05:38 -0400 Received: from mail-qt1-f195.google.com ([209.85.160.195]:38049 "EHLO mail-qt1-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725875AbfC1OFi (ORCPT ); Thu, 28 Mar 2019 10:05:38 -0400 Received: by mail-qt1-f195.google.com with SMTP id d13so18485003qth.5 for ; Thu, 28 Mar 2019 07:05:37 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=cmpxchg-org.20150623.gappssmtp.com; s=20150623; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=OZsN+KjF6P0mNOSjgzFw3fqkoVmkhJo6T0apoMNZd18=; b=0Cj5ef94+CRYvijQ1AKj4UAqc1sd4cV79FVilXIDCXG80htX0gpXBVJh72zcQtcJlO 83oIVfRWYgGi6lHslyDtBI3ISnwIp+M5c97aBdGGSBoOLO7P0Kq8VgRgXDXrDFSj6+Ly Fh1kQXuELevRdHZlCwh6RbGwkyggA16Rmaen1DQAvAgsDUxHHE4m5zGtKKuYRdDomMbS p/aamlRNU+LM7rc6ak7M6DGzDhKOv3Bos/DVp1U6uVikCyCEn5ZD5js8unIeQTNtJZZM TmQIYr/CClYewtDHXV+F6YqaE9UWtU8KTpv5bB3oZQlejMPBoKJYTh5o/oDASbqx/6V7 Gx+g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=OZsN+KjF6P0mNOSjgzFw3fqkoVmkhJo6T0apoMNZd18=; b=hqxdep5nPMG2Fa0WRdahXBigwLnMV/4VDBW9lMg6wQnleHjxMjA58mjVunsECG3rvr SXivONh9ACuiMIbxZpFZUy11nyar8dGZCLsXWhq2OQf4CYnGNOK6lRrJIRcQJ0LwXyAB ToAF44xlzh2VM7kGQJYA4y6WGgrL/pKnC00mmCoqBDUj+KK1xGguc2oG/DwaV4zq6zQa Pt2TXZXL69snviNafiUAOWUqNuBjKLKp1jIBg7SFuEguPX8Gg0TjmuoZue0MeU5SRt8C DQeKKXzOuO/X5Kycz5WLLs8mFLH0ibgkSRZUz4rAjcnKTuRYqtCgTch+igEZvCSv3yyQ t2Yw== X-Gm-Message-State: APjAAAV/X3sa1NKFKeR+9j0ekyNMvz/IsDECOe5Dn3DgESuvxamYDDvI DRSssLDYCznQMh9uOVR4bFNmBg== X-Google-Smtp-Source: APXvYqzhlNfyJWYewSPQn9Q2ZGgaGwby4p0a0N5/E0M0U5RjcC3vbzUObNwUIUTLX3Be4ykk3m8SjQ== X-Received: by 2002:ac8:3fbc:: with SMTP id d57mr34297897qtk.96.1553781937336; Thu, 28 Mar 2019 07:05:37 -0700 (PDT) Received: from localhost (pool-108-27-252-85.nycmny.fios.verizon.net. [108.27.252.85]) by smtp.gmail.com with ESMTPSA id b37sm10221707qtb.92.2019.03.28.07.05.36 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Thu, 28 Mar 2019 07:05:36 -0700 (PDT) Date: Thu, 28 Mar 2019 10:05:35 -0400 From: Johannes Weiner To: Greg Thelen Cc: Roman Gushchin , Andrew Morton , Michal Hocko , Vladimir Davydov , Tejun Heo , "linux-mm@kvack.org" , "linux-kernel@vger.kernel.org" Subject: Re: [PATCH] writeback: sum memcg dirty counters as needed Message-ID: <20190328140535.GA15622@cmpxchg.org> References: <20190307165632.35810-1-gthelen@google.com> <20190322181517.GA12378@tower.DHCP.thefacebook.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.11.4 (2019-03-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Mar 27, 2019 at 03:29:47PM -0700, Greg Thelen wrote: > On Fri, Mar 22, 2019 at 11:15 AM Roman Gushchin wrote: > > On Thu, Mar 07, 2019 at 08:56:32AM -0800, Greg Thelen wrote: > > > + int cpu; > > > + > > > + for_each_online_cpu(cpu) > > > + x += per_cpu_ptr(memcg->stat_cpu, cpu)->count[idx]; > > > + if (x < 0) > > > + x = 0; > > > +#endif > > > + return x; > > > +} > > > > Also, isn't it worth it to generalize memcg_page_state() instead? > > By adding an bool exact argument? I believe dirty balance is not > > the only place, where we need a better accuracy. > > Nod. I'll provide a more general version of memcg_page_state(). I'm > testing updated (forthcoming v2) patch set now with feedback from > Andrew and Roman. I'm working on a patch series that reworks the memcg_page_state() API and by far the most callers do NOT need the exact numbers. So I'd ask to please keep this a separate function so I don't have to update tens of callsites to pass "false". Thanks!