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=-2.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no 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 352F1C433E0 for ; Fri, 15 May 2020 13:01:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0CE982074D for ; Fri, 15 May 2020 13:01:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726241AbgEONBM (ORCPT ); Fri, 15 May 2020 09:01:12 -0400 Received: from mga04.intel.com ([192.55.52.120]:57469 "EHLO mga04.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726122AbgEONBM (ORCPT ); Fri, 15 May 2020 09:01:12 -0400 IronPort-SDR: iowo3bbAvMwOtBVjIdGGkcX3P8S9OpOl6i6aq4ib09vdyPDf46nsoH6MbWWzeX1i58T/+bIbUR JujDjj7QLsYA== X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga003.jf.intel.com ([10.7.209.27]) by fmsmga104.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 15 May 2020 06:01:11 -0700 IronPort-SDR: LD0v8IRgyKsI2N0qTF2oCgjqjKSFPz+bmzf9t6tr/E/g16YW+ncniz22UkCOkB7M2ldj3HWkTg DmTL9fMWBETw== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.73,395,1583222400"; d="scan'208";a="263183050" Received: from shbuild999.sh.intel.com (HELO localhost) ([10.239.146.107]) by orsmga003.jf.intel.com with ESMTP; 15 May 2020 06:01:07 -0700 Date: Fri, 15 May 2020 21:01:07 +0800 From: Feng Tang To: Michal Hocko Cc: Andrew Morton , Johannes Weiner , Matthew Wilcox , Mel Gorman , Kees Cook , Luis Chamberlain , Iurii Zaikin , "Kleen, Andi" , "Chen, Tim C" , "Hansen, Dave" , "Huang, Ying" , "linux-mm@kvack.org" , "linux-kernel@vger.kernel.org" Subject: Re: [PATCH 2/3] mm/util.c: make vm_memory_committed() more accurate Message-ID: <20200515130107.GG69177@shbuild999.sh.intel.com> References: <1588922717-63697-1-git-send-email-feng.tang@intel.com> <1588922717-63697-3-git-send-email-feng.tang@intel.com> <20200515072307.GG29153@dhcp22.suse.cz> <20200515081109.GD69177@shbuild999.sh.intel.com> <20200515090440.GN29153@dhcp22.suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200515090440.GN29153@dhcp22.suse.cz> User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, May 15, 2020 at 05:04:40PM +0800, Michal Hocko wrote: > On Fri 15-05-20 16:11:09, Feng Tang wrote: > > On Fri, May 15, 2020 at 03:23:07PM +0800, Michal Hocko wrote: > > > On Fri 08-05-20 15:25:16, Feng Tang wrote: > > > > percpu_counter_sum_positive() will provide more accurate info. > > > > > > Why do we need that? > > > > This is a preparation for patch 3/3, which will enlarge the batch size > > of percpu-counter 'vm_committed_as'. Andi Kleen concerned that may > > hurt the accuracy for those readers (currently only /proc/meminfo > > and hyperV balloon drivers for status check) > > > > As in worst case, the deviation could be 'batch * nr_cpus', and > > with patch 3/3, that could be totalram_pages/16. > > This information belongs to the changelog. Will add it in v3, thanks - Feng