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=-3.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS 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 5E190C432C0 for ; Sun, 1 Dec 2019 01:57:35 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 1A5EC20873 for ; Sun, 1 Dec 2019 01:57:35 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="D5wkfYio" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 1A5EC20873 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linux-foundation.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id BE8EB6B037A; Sat, 30 Nov 2019 20:57:34 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id B992B6B037C; Sat, 30 Nov 2019 20:57:34 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id A61976B037D; Sat, 30 Nov 2019 20:57:34 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0064.hostedemail.com [216.40.44.64]) by kanga.kvack.org (Postfix) with ESMTP id 8E5016B037A for ; Sat, 30 Nov 2019 20:57:34 -0500 (EST) Received: from smtpin21.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with SMTP id 43FC2824999B for ; Sun, 1 Dec 2019 01:57:34 +0000 (UTC) X-FDA: 76214910828.21.glue13_42106ce10ea37 X-HE-Tag: glue13_42106ce10ea37 X-Filterd-Recvd-Size: 3606 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf22.hostedemail.com (Postfix) with ESMTP for ; Sun, 1 Dec 2019 01:57:33 +0000 (UTC) Received: from localhost.localdomain (c-73-231-172-41.hsd1.ca.comcast.net [73.231.172.41]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id CF13F2082E; Sun, 1 Dec 2019 01:57:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1575165453; bh=3psEDXDdfYuBV/kjrYa967oPAqNh0lcS+E4+zQo8hos=; h=Date:From:To:Subject:From; b=D5wkfYioaze+lr5DOEGzZDX4zppA+v4BYnHSgsEOctq3TLSqno8QFin06LtqJvNvy bxCu70eCpWVvShuhuMiVHmBmBSbzau1GsSrNcTcs+X6IHraq13ub587iHnWUJDsYwD tOwvw+1M/b9BBpj4mQwzsNbX9wVMekj2P13HQ1yM= Date: Sat, 30 Nov 2019 17:57:32 -0800 From: akpm@linux-foundation.org To: akpm@linux-foundation.org, dan.j.williams@intel.com, dave.hansen@linux.intel.com, fengguang.wu@intel.com, linux-mm@kvack.org, mgorman@suse.de, mhocko@suse.com, mingo@kernel.org, mm-commits@vger.kernel.org, peterz@infradead.org, riel@redhat.com, torvalds@linux-foundation.org, ying.huang@intel.com Subject: [patch 140/158] autonuma: reduce cache footprint when scanning page tables Message-ID: <20191201015732.Ecjld8a-U%akpm@linux-foundation.org> User-Agent: s-nail v14.8.16 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: From: Huang Ying Subject: autonuma: reduce cache footprint when scanning page tables In auto NUMA balancing page table scanning, if the pte_protnone() is true, the PTE needs not to be changed because it's in target state already. So other checking on corresponding struct page is unnecessary too. So, if we check pte_protnone() firstly for each PTE, we can avoid unnecessary struct page accessing, so that reduce the cache footprint of NUMA balancing page table scanning. In the performance test of pmbench memory accessing benchmark with 80:20 read/write ratio and normal access address distribution on a 2 socket Intel server with Optance DC Persistent Memory, perf profiling shows that the autonuma page table scanning time reduces from 1.23% to 0.97% (that is, reduced 21%) with the patch. Link: http://lkml.kernel.org/r/20191101075727.26683-3-ying.huang@intel.com Signed-off-by: "Huang, Ying" Acked-by: Mel Gorman Cc: Michal Hocko Cc: Rik van Riel Cc: Peter Zijlstra Cc: Ingo Molnar Cc: Dave Hansen Cc: Dan Williams Cc: Fengguang Wu Signed-off-by: Andrew Morton --- mm/mprotect.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) --- a/mm/mprotect.c~autonuma-reduce-cache-footprint-when-scanning-page-tables +++ a/mm/mprotect.c @@ -80,6 +80,10 @@ static unsigned long change_pte_range(st if (prot_numa) { struct page *page; + /* Avoid TLB flush if possible */ + if (pte_protnone(oldpte)) + continue; + page = vm_normal_page(vma, addr, oldpte); if (!page || PageKsm(page)) continue; @@ -97,10 +101,6 @@ static unsigned long change_pte_range(st if (page_is_file_cache(page) && PageDirty(page)) continue; - /* Avoid TLB flush if possible */ - if (pte_protnone(oldpte)) - continue; - /* * Don't mess with PTEs if page is already on the node * a single-threaded process is running on. _