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=-10.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 EC6FCC433B4 for ; Wed, 21 Apr 2021 07:40:53 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 578586142C for ; Wed, 21 Apr 2021 07:40:53 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 578586142C Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=suse.de Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id A24676B006C; Wed, 21 Apr 2021 03:40:52 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 9D4536B006E; Wed, 21 Apr 2021 03:40:52 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 8751B6B0070; Wed, 21 Apr 2021 03:40:52 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0035.hostedemail.com [216.40.44.35]) by kanga.kvack.org (Postfix) with ESMTP id 6EF586B006C for ; Wed, 21 Apr 2021 03:40:52 -0400 (EDT) Received: from smtpin16.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id 25CD03623 for ; Wed, 21 Apr 2021 07:40:52 +0000 (UTC) X-FDA: 78055577544.16.8B5ECC5 Received: from mx2.suse.de (mx2.suse.de [195.135.220.15]) by imf15.hostedemail.com (Postfix) with ESMTP id 5CA1EA000398 for ; Wed, 21 Apr 2021 07:40:49 +0000 (UTC) X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id 929D6B13D; Wed, 21 Apr 2021 07:40:50 +0000 (UTC) Date: Wed, 21 Apr 2021 08:40:47 +0100 From: Mel Gorman To: Andrew Morton Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Peter Zijlstra , Peter Xu , Johannes Weiner , Vlastimil Babka , Matthew Wilcox , Will Deacon , Michel Lespinasse , Arjun Roy , Huang Ying , "Kirill A. Shutemov" Subject: Re: [PATCH -V3] NUMA balancing: reduce TLB flush via delaying mapping on hint page fault Message-ID: <20210421074047.GD15768@suse.de> References: <20210408132236.1175607-1-ying.huang@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-15 Content-Disposition: inline In-Reply-To: <20210408132236.1175607-1-ying.huang@intel.com> User-Agent: Mutt/1.10.1 (2018-07-13) X-Rspamd-Queue-Id: 5CA1EA000398 X-Stat-Signature: rea3ccuebxr4565nxm3dy9u5cu3ppzdf X-Rspamd-Server: rspam02 Received-SPF: none (suse.de>: No applicable sender policy available) receiver=imf15; identity=mailfrom; envelope-from=""; helo=mx2.suse.de; client-ip=195.135.220.15 X-HE-DKIM-Result: none/none X-HE-Tag: 1618990849-710378 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 Thu, Apr 08, 2021 at 09:22:36PM +0800, Huang Ying wrote: > With NUMA balancing, in hint page fault handler, the faulting page > will be migrated to the accessing node if necessary. During the > migration, TLB will be shot down on all CPUs that the process has run > on recently. Because in the hint page fault handler, the PTE will be > made accessible before the migration is tried. The overhead of TLB > shooting down can be high, so it's better to be avoided if possible. > In fact, if we delay mapping the page until migration, that can be > avoided. This is what this patch doing. > > Signed-off-by: "Huang, Ying" > Reviewed-by: Mel Gorman > Cc: Peter Zijlstra > Cc: Peter Xu > Cc: Johannes Weiner > Cc: Vlastimil Babka > Cc: "Matthew Wilcox" > Cc: Will Deacon > Cc: Michel Lespinasse > Cc: Arjun Roy > Cc: "Kirill A. Shutemov" Hi Andrew, I do not see this in the mmots tree. Was something missed in this patch that needs fixing or did it just fall through the cracks? Thanks. -- Mel Gorman SUSE Labs