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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2E47EC433F5 for ; Wed, 10 Nov 2021 08:37:03 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id C2B1F611F2 for ; Wed, 10 Nov 2021 08:37:02 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org C2B1F611F2 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kvack.org Received: by kanga.kvack.org (Postfix) id 5ADAD6B006C; Wed, 10 Nov 2021 03:37:02 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 55DA26B0071; Wed, 10 Nov 2021 03:37:02 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 44D096B0072; Wed, 10 Nov 2021 03:37:02 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0015.hostedemail.com [216.40.44.15]) by kanga.kvack.org (Postfix) with ESMTP id 375116B006C for ; Wed, 10 Nov 2021 03:37:02 -0500 (EST) Received: from smtpin28.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with ESMTP id F3BB7184DB45A for ; Wed, 10 Nov 2021 08:37:01 +0000 (UTC) X-FDA: 78792365484.28.C4F42CC Received: from desiato.infradead.org (desiato.infradead.org [90.155.92.199]) by imf23.hostedemail.com (Postfix) with ESMTP id 711D790000BC for ; Wed, 10 Nov 2021 08:36:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=desiato.20200630; 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=QTjq4+NF5gS81UUXJMbCMX9lOOw+gbyrkDDIl5OUPWY=; b=jaXYQgzmD506gRK4y9KTKker1O 4R4JxVIlz8saIi+ToShOmq8db/j62hdPz9YhwFHZuhH7ARyPaDPT8uV4LGkpgmme7/E9YwjBHSheH rj1DaPmJ4+Nm0O5cXqbEwKy6sHOKQQU2adS3ye4G//L5ERim1ymenV/weWsfuuxO++EpFF/xpl9UN kCpnGp/fSv3y5p9pWUWJTs9uCA7GUN1J6arccu/q4+rXUoeTCCXWisICElNzpqa53FDn7ktEF+xj5 9A4ycCWvPIT5XLKcd4lFhOuVOrCwk/8EKfypQaLAibhuDRNskoOc0dqstLdF42XsuQIEkJsN3qI1b 2OFJOGLw==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=noisy.programming.kicks-ass.net) by desiato.infradead.org with esmtpsa (Exim 4.94.2 #2 (Red Hat Linux)) id 1mkj6A-00FF0C-Ku; Wed, 10 Nov 2021 08:36:50 +0000 Received: from hirez.programming.kicks-ass.net (hirez.programming.kicks-ass.net [192.168.1.225]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (Client did not present a certificate) by noisy.programming.kicks-ass.net (Postfix) with ESMTPS id 863E430003C; Wed, 10 Nov 2021 09:36:49 +0100 (CET) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id 6A365212EE584; Wed, 10 Nov 2021 09:36:49 +0100 (CET) Date: Wed, 10 Nov 2021 09:36:49 +0100 From: Peter Zijlstra To: Zhaoyang Huang Cc: Vincent Guittot , Dietmar Eggemann , Ke Wang , xuewen.yan@unisoc.com, Johannes Weiner , Andrew Morton , Michal Hocko , Vladimir Davydov , Zhaoyang Huang , "open list:MEMORY MANAGEMENT" , LKML Subject: Re: [Resend PATCH] psi : calc cfs task memstall time more precisely Message-ID: References: <1634278612-17055-1-git-send-email-huangzhaoyang@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Authentication-Results: imf23.hostedemail.com; dkim=pass header.d=infradead.org header.s=desiato.20200630 header.b=jaXYQgzm; spf=none (imf23.hostedemail.com: domain of peterz@infradead.org has no SPF policy when checking 90.155.92.199) smtp.mailfrom=peterz@infradead.org; dmarc=none X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: 711D790000BC X-Stat-Signature: qn5dwonpf6md69w3q7yxgg6i47jnzrq1 X-HE-Tag: 1636533406-341484 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 Wed, Nov 10, 2021 at 09:37:00AM +0800, Zhaoyang Huang wrote: > On Tue, Nov 9, 2021 at 10:56 PM Peter Zijlstra wrote: > > > > On Tue, Nov 02, 2021 at 03:47:33PM -0400, Johannes Weiner wrote: > > > CC peterz as well for rt and timekeeping magic > > > > > > On Fri, Oct 15, 2021 at 02:16:52PM +0800, Huangzhaoyang wrote: > > > > From: Zhaoyang Huang > > > > > > > > In an EAS enabled system, there are two scenarios discordant to current design, > > > > > > > > 1. workload used to be heavy uneven among cores for sake of scheduler policy. > > > > RT task usually preempts CFS task in little core. > > > > 2. CFS task's memstall time is counted as simple as exit - entry so far, which > > > > ignore the preempted time by RT, DL and Irqs. > > > > It ignores preemption full-stop. I don't see why RT/IRQ should be > > special cased here. > As Johannes comments, what we are trying to solve is mainly the > preempted time of the CFS task by RT/IRQ, NOT the RT/IRQ themselves. > Could you please catch up the recent reply of Dietmar, which maybe > provide more information. In that case NAK.