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=0.2 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED,URIBL_DBL_ABUSE_MALW,USER_AGENT_SANE_1 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 87EBFC35254 for ; Wed, 5 Feb 2020 12:50:07 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 3DF8E20702 for ; Wed, 5 Feb 2020 12:50:07 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="klx4l0hI" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 3DF8E20702 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender:Content-Type: Content-Transfer-Encoding:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:Date:Message-ID:From: References:To:Subject:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=lUaaYdti0l2YNUzYpRsknl9ExlcM5MmNfjHdZEUIQ7o=; b=klx4l0hIfBZmme3tqvm03itFU LgEZbz93VnvlgRIYDcmMvBsVJ2StNf9BPf/QpdoWw4HvlgzVTMzBoW9HKqMaO7yKF2Fljc2wTauJw KSD2fcPG6Ql39OS6MmVp83jMylqUzgPUJKLUEz75a1n99s4clSj9wCf1YXQuYIauolRZfvjyMakVe Gp+0jx4BLbmolrpOFubHd09C+2KL+Dxucb2vryMOYNmGeT7Qb0aH9vCXAsZHem7Ts9eh9oWxxYnGg ydb9EiednavprwbCuCyFoe/YWjEPqN+nIqz3K2YtGGzyTVUyj6cMxXBB+aanMe8TVX3I2SIbL8gOc cz4oplfKg==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1izK83-0002Np-8N; Wed, 05 Feb 2020 12:50:03 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1izK80-0002C1-6r for linux-arm-kernel@lists.infradead.org; Wed, 05 Feb 2020 12:50:01 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 057631FB; Wed, 5 Feb 2020 04:49:56 -0800 (PST) Received: from [10.37.12.130] (unknown [10.37.12.130]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 3DB2D3F52E; Wed, 5 Feb 2020 04:49:34 -0800 (PST) Subject: Re: [PATCH 3/3] ARM: exynos_defconfig: Enable Energy Model framework To: Krzysztof Kozlowski References: <20200127215453.15144-1-lukasz.luba@arm.com> <20200127215453.15144-4-lukasz.luba@arm.com> <20200131204118.GA27284@kozik-lap> From: Lukasz Luba Message-ID: Date: Wed, 5 Feb 2020 12:49:26 +0000 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.9.0 MIME-Version: 1.0 In-Reply-To: <20200131204118.GA27284@kozik-lap> Content-Language: en-US X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200205_045000_337087_B0E9A12F X-CRM114-Status: GOOD ( 20.24 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: mark.rutland@arm.com, devicetree@vger.kernel.org, "linux-samsung-soc@vger.kernel.org" , linux-pm@vger.kernel.org, =?UTF-8?Q?Bart=c5=82omiej_=c5=bbo=c5=82nierkiewicz?= , "linux-kernel@vger.kernel.org" , robh+dt@kernel.org, Chanwoo Choi , kyungmin.park@samsung.com, kgene@kernel.org, myungjoo.ham@samsung.com, dietmar.eggemann@arm.com, linux-arm-kernel@lists.infradead.org Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org Hi Krzysztof, On 1/31/20 8:41 PM, Krzysztof Kozlowski wrote: > On Fri, Jan 31, 2020 at 05:30:46PM +0000, Lukasz Luba wrote: > >>> >>>> |-----------------------------------------------|--------------- >>>> | performance | SchedUtil | SchedUtil | performance >>>> | governor | governor | governor | governor >>>> | | w/o EAS | w/ EAS | >>>> ----------------|---------------|---------------|---------------|--------------- >>>> hackbench w/ PL | 12.7s | 11.7s | 12.0s | 13.0s - 12.2s >>>> hackbench w/o PL| 9.2s | 8.1s | 8.2s | 9.2s - 8.4s >>> >>> Why does the performance different before and after this patch? >> >> Probably due to better locality and cache utilization. I can see that >> there is ~700k context switches vs ~450k and ~160k migrations vs ~50k. >> If you need to communicate two threads in different clusters, it will go >> through CCI. > > Mhmm... I was not specific - I mean, "performance governor". All this > you mentioned should not differ between performance governor before and > after. However once you have 12.7, then 13.0 - 12.2. Unless multi-core > scheduler affects it... but then these numbers here are not showing > only this change, but also the SCHED_MC effect. In such case each of > commits should be coming with their own numbers. Agree, I should have not put 'this patch set' in the commit msg. It should go into the cover letter and avoid this confusion. You are right with ' Unless multi-core scheduler affects it...', that's why when the SCHED_MC is missing, the decisions about task placing might cause this variation and delay '13.0 - 12.2' seconds. > >> As mentioned in response to patch 1/3. The fist patch would create MC >> domain, something different than Energy Model or EAS. The decisions in >> the scheduler would be different. >> >> I can merge 1/3 and 3/3 if you like, though. > > I understand now that their independent. Still, they are part of one > goal to tune the scheduler for Exynos platform. Splitting these looks > too much, like enabling multiple drivers one after another. > > However if you provide numbers for each of cases (before patches, multi > core scheduler, energy model with DTS), then I see benefit of splitting > it. Each commit would have its own rationale. I am not sure if it is > worth such investigation - that's just defconfig... distros might ignore > it anyway. Good point, and I agree that it would require more investigation, for which unfortunately I don't have currently spare cycles. Should I merge patch 1/3 and 3/3 and send the v2 with a cover letter which would have the test results? Regards, Lukasz _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel