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 50210C433EF for ; Sun, 3 Jul 2022 13:48:21 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 767576B0072; Sun, 3 Jul 2022 09:48:20 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 717A26B0073; Sun, 3 Jul 2022 09:48:20 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 606D46B0074; Sun, 3 Jul 2022 09:48:20 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0013.hostedemail.com [216.40.44.13]) by kanga.kvack.org (Postfix) with ESMTP id 4DFA06B0072 for ; Sun, 3 Jul 2022 09:48:20 -0400 (EDT) Received: from smtpin19.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay11.hostedemail.com (Postfix) with ESMTP id 1E65380BF7 for ; Sun, 3 Jul 2022 13:48:20 +0000 (UTC) X-FDA: 79645917960.19.DDCD782 Received: from out30-56.freemail.mail.aliyun.com (out30-56.freemail.mail.aliyun.com [115.124.30.56]) by imf19.hostedemail.com (Postfix) with ESMTP id 236621A003F for ; Sun, 3 Jul 2022 13:48:16 +0000 (UTC) X-Alimail-AntiSpam:AC=PASS;BC=-1|-1;BR=01201311R141e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=ay29a033018046060;MF=baolin.wang@linux.alibaba.com;NM=1;PH=DS;RN=5;SR=0;TI=SMTPD_---0VIBbN6O_1656856088; Received: from 30.0.187.160(mailfrom:baolin.wang@linux.alibaba.com fp:SMTPD_---0VIBbN6O_1656856088) by smtp.aliyun-inc.com; Sun, 03 Jul 2022 21:48:09 +0800 Message-ID: Date: Sun, 3 Jul 2022 21:48:13 +0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:91.0) Gecko/20100101 Thunderbird/91.10.0 Subject: Re: [RFC PATCH v3 1/3] mm: Factor out the pagetable pages account into new helper function To: Mike Rapoport Cc: akpm@linux-foundation.org, willy@infradead.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org References: <9c527d4d2eb1f457306e575ce16c6acdd8141e02.1656586863.git.baolin.wang@linux.alibaba.com> <13b2cc16-fb1a-eeb8-7a15-d20f4ba42a48@linux.alibaba.com> From: Baolin Wang In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1656856099; a=rsa-sha256; cv=none; b=hzsN8Pu/dSgEolOxjXtxxQwL0JrvA1DKS+vT+lg4YBYIubYQzdMk08NBTuX9diTNwOiGFP 0LOTdkZ0W2P0x2TjyPv87bX6C36L6x6fMcCEi5K5kbGV0AAKX98ZwTzi5VIno5EHnl/5f4 9vm5yGCrTI4vl4L0upap3GL/qJHTFRA= ARC-Authentication-Results: i=1; imf19.hostedemail.com; dkim=none; dmarc=pass (policy=none) header.from=alibaba.com; spf=pass (imf19.hostedemail.com: domain of baolin.wang@linux.alibaba.com designates 115.124.30.56 as permitted sender) smtp.mailfrom=baolin.wang@linux.alibaba.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1656856099; 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:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=uLD8GCcQyKXf2/tOYhpDTbe3Scp+8vP7nLY1YKuOItQ=; b=s1URinhBxJK3i1Igg+r+PZVsYMA1TzE4lklZ8955o4hTaYi7u3fnWkZSaNscyvp7JLT//x dG2QuLoZa7DHW8TVdT2eDJyOejXt1KqpavFblFxf+oYPXkpUQlkwhSr5xO9pK5SYq4H49H TOjKrwJqIjIWU0ZKvpQUbHW7gWqJ3KU= X-Rspamd-Server: rspam05 X-Rspamd-Queue-Id: 236621A003F Authentication-Results: imf19.hostedemail.com; dkim=none; dmarc=pass (policy=none) header.from=alibaba.com; spf=pass (imf19.hostedemail.com: domain of baolin.wang@linux.alibaba.com designates 115.124.30.56 as permitted sender) smtp.mailfrom=baolin.wang@linux.alibaba.com X-Rspam-User: X-Stat-Signature: po3sp7aiemm4tm3ez67rf4fjejj9saet X-HE-Tag: 1656856096-102586 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 7/2/2022 6:15 PM, Mike Rapoport wrote: > On Fri, Jul 01, 2022 at 04:00:59PM +0800, Baolin Wang wrote: >> >> >> On 6/30/2022 10:11 PM, Mike Rapoport wrote: >>> On Thu, Jun 30, 2022 at 07:11:14PM +0800, Baolin Wang wrote: >>>> Factor out the pagetable pages account into new helper functions to avoid >>>> duplicated code. Meanwhile these helper functions also will be used to >>>> account pagetable pages which do not need split pagetale lock. >>>> >>>> Meanwhile convert to use mod_lruvec_page_state() in case of non-order-0 >>>> page table allocation. >>> >>> These are *very* rare. I think only parisc may have non-order-0 pmd and pud >>> tables. >> >> s390 also has non-order-0 page table allocation, but they both do not use >> the generic page table allocation now. >> >>> With that, I'd suggest making use of compound_nr() build time opt-in. >> >> After more thinking, I'd prefer to change back to use >> inc_lruvec_page_state()/dec_lruvec_page_state(), since now no architecures >> will need non-order-0 page table allocation. >> >> After this patchset, I plan to convert parisc and s390 to use generic >> pagetable allocation, then I will add non-order-0 page table allocation >> support. Like Matthew suggested, maybe I need change the API to pass the >> number of pages. > > I think it would be simpler to add proper accounting to s390 and parisc > versions than make them use the generic allocation functions. Moreover, API > change to support these cases feels like unnecessary churn to me. Got it. Thanks.