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=-5.1 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A, SPF_HELO_NONE,SPF_PASS,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 8E1EDC48BE5 for ; Wed, 23 Jun 2021 12:57:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 721FF60698 for ; Wed, 23 Jun 2021 12:57:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230299AbhFWNAI (ORCPT ); Wed, 23 Jun 2021 09:00:08 -0400 Received: from alexa-out-sd-01.qualcomm.com ([199.106.114.38]:38663 "EHLO alexa-out-sd-01.qualcomm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230019AbhFWNAI (ORCPT ); Wed, 23 Jun 2021 09:00:08 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=quicinc.com; i=@quicinc.com; q=dns/txt; s=qcdkim; t=1624453071; x=1655989071; h=subject:to:cc:references:from:message-id:date: mime-version:in-reply-to:content-transfer-encoding; bh=15/CAV2snDdvyAJxjJ5PKrRh/F+DBXa8aHprIfhpyUU=; b=M+SFXFoWK8Hl7ISVGlRLBol2RTa2nfzAjsRO+8wMU6NVQ/iKy/PCZBn5 CELXVUGPxLGgqr9Fph8/sDGancTgMzW6tfdeGgvwCeX3KYg00/sEeEvBR jmwpYuQBABP/oJJVM7BMo3Yw0dqavO00nhq617EJGeDU3JRngCkZgap+Q 4=; Received: from unknown (HELO ironmsg02-sd.qualcomm.com) ([10.53.140.142]) by alexa-out-sd-01.qualcomm.com with ESMTP; 23 Jun 2021 05:57:50 -0700 X-QCInternal: smtphost Received: from nasanexm03e.na.qualcomm.com ([10.85.0.48]) by ironmsg02-sd.qualcomm.com with ESMTP/TLS/AES256-SHA; 23 Jun 2021 05:57:49 -0700 Received: from [10.38.240.33] (10.80.80.8) by nasanexm03e.na.qualcomm.com (10.85.0.48) with Microsoft SMTP Server (TLS) id 15.0.1497.18; Wed, 23 Jun 2021 05:57:47 -0700 Subject: Re: [PATCH V3 0/4] cpufreq: cppc: Add support for frequency invariance To: Viresh Kumar CC: Rafael Wysocki , Ionela Voinescu , Ben Segall , Daniel Bristot de Oliveira , Dietmar Eggemann , Greg Kroah-Hartman , Ingo Molnar , Juri Lelli , Mel Gorman , Peter Zijlstra , "Rafael J. Wysocki" , Steven Rostedt , Sudeep Holla , Vincent Guittot , Will Deacon , , , , "Paul E. McKenney" , "Rafael J. Wysocki" References: <09a39f5c-b47b-a931-bf23-dc43229fb2dd@quicinc.com> <20210623041613.v2lo3nidpgw37abl@vireshk-i7> From: Qian Cai Message-ID: <2c540a58-4fef-5a3d-85b4-8862721b6c4f@quicinc.com> Date: Wed, 23 Jun 2021 08:57:46 -0400 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.11.0 MIME-Version: 1.0 In-Reply-To: <20210623041613.v2lo3nidpgw37abl@vireshk-i7> Content-Type: text/plain; charset="utf-8" Content-Language: en-US Content-Transfer-Encoding: 7bit X-Originating-IP: [10.80.80.8] X-ClientProxiedBy: nasanexm03d.na.qualcomm.com (10.85.0.91) To nasanexm03e.na.qualcomm.com (10.85.0.48) Precedence: bulk List-ID: X-Mailing-List: linux-acpi@vger.kernel.org On 6/23/2021 12:16 AM, Viresh Kumar wrote: > On 21-06-21, 16:48, Qian Cai wrote: >> >> >> On 6/21/2021 5:19 AM, Viresh Kumar wrote: >>> CPPC cpufreq driver is used for ARM servers and this patch series tries to >>> provide counter-based frequency invariance support for them in the absence for >>> architecture specific counters (like AMUs). >> >> Viresh, this series works fine on my quick tests so far. > > Do you want me to add your Tested-by for the series ? Viresh, I am afraid I don't feel comfortable yet. I have a few new tests in development, and will provide an update once ready. Also, I noticed the delivered perf is even smaller than lowest_perf (100). # cat /sys/devices/system/cpu/cpu8/acpi_cppc/feedback_ctrs ref:103377547901 del:54540736873 # cat /sys/devices/system/cpu/cpu8/acpi_cppc/feedback_ctrs ref:103379170101 del:54541599117 100 * (54541599117 - 54540736873) / (103379170101 - 103377547901) = 53 My understanding is that the delivered perf should fail into the range between lowest_perf and highest_perf. Is that assumption correct? This happens on 5.4-based kernel, so I am in process running your series on that system to see if there is any differences. In any case, if it is a bug it is pre-existing, but I'd like to understand a bit better in that front first.