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 8E613C433EF for ; Fri, 18 Mar 2022 01:46:52 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 0D6228D0002; Thu, 17 Mar 2022 21:46:52 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 0859B8D0001; Thu, 17 Mar 2022 21:46:52 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id EB6818D0002; Thu, 17 Mar 2022 21:46:51 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0247.hostedemail.com [216.40.44.247]) by kanga.kvack.org (Postfix) with ESMTP id D903D8D0001 for ; Thu, 17 Mar 2022 21:46:51 -0400 (EDT) Received: from smtpin28.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id 8AB609F326 for ; Fri, 18 Mar 2022 01:46:51 +0000 (UTC) X-FDA: 79255818222.28.186393D Received: from casper.infradead.org (casper.infradead.org [90.155.50.34]) by imf09.hostedemail.com (Postfix) with ESMTP id 8BA5314001C for ; Fri, 18 Mar 2022 01:46:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=Cb1mYMgEq/l616np20E54xs6ulWzv/0BUcsNzaw04KQ=; b=ZlE1sBFXCVUevIjXy9KJv0SqD1 vl0FFdYl8O7uR2ZS227nfU9oxHUt3h3xmwVWDMPit/s6huCC/CuS6jOLRmVc6PrbAD9yKyrXLOETO zG2wllFDK0zml7qh17qMRci5Re+9GL3JGjH4+NBP6VeWA8kLaNfuTPFjQDbgM3ikg0boLO1TRYRHS ywGVwgmLviZ+KY/ZECwdcOeSgcjSCv1UmEeUO9HzMYbL45V4L2pXqrebCkXsvv1eseKjkaVQiwTw0 jdcAK3drF4wTCF/gyGio5yzz7V6LKNABaG9g7w+Kcgez4Z10xJ8Y8tdvaq8yPZozBvp5+p9rqkrKS LktUOo7Q==; Received: from willy by casper.infradead.org with local (Exim 4.94.2 #2 (Red Hat Linux)) id 1nV1hP-007Vyf-8J; Fri, 18 Mar 2022 01:46:39 +0000 Date: Fri, 18 Mar 2022 01:46:39 +0000 From: Matthew Wilcox To: maobibo Cc: Andrew Morton , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Anshuman Khandual Subject: Re: [PATCH v2] mm: add access/dirty bit on numa page fault Message-ID: References: <20220317065033.2635123-1-maobibo@loongson.cn> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Rspam-User: Authentication-Results: imf09.hostedemail.com; dkim=pass header.d=infradead.org header.s=casper.20170209 header.b=ZlE1sBFX; dmarc=none; spf=none (imf09.hostedemail.com: domain of willy@infradead.org has no SPF policy when checking 90.155.50.34) smtp.mailfrom=willy@infradead.org X-Rspamd-Server: rspam09 X-Rspamd-Queue-Id: 8BA5314001C X-Stat-Signature: 8pf9cuy3qxqmtecfxz97o3s4tbau7nch X-HE-Tag: 1647568010-501111 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 Fri, Mar 18, 2022 at 09:01:32AM +0800, maobibo wrote: > > Is this a correctness problem, in which case this will need to be > > backported, or is this a performance problem, in which case can you > > share some numbers? > It is only performance issue, and there is no obvious performance > improvement for general workloads on my hand, but I do not test > it on microbenchmark. ... if there's no performance improvement, why should we apply this patch? Confused.