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 5DCFAC433EF for ; Wed, 10 Nov 2021 08:37:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 44533611C0 for ; Wed, 10 Nov 2021 08:37:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230235AbhKJIjw (ORCPT ); Wed, 10 Nov 2021 03:39:52 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45602 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229653AbhKJIjv (ORCPT ); Wed, 10 Nov 2021 03:39:51 -0500 Received: from desiato.infradead.org (desiato.infradead.org [IPv6:2001:8b0:10b:1:d65d:64ff:fe57:4e05]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 22D86C061764 for ; Wed, 10 Nov 2021 00:37:04 -0800 (PST) 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: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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.