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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 73F6FCD13D8 for ; Mon, 18 Sep 2023 18:23:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229578AbjIRSXh (ORCPT ); Mon, 18 Sep 2023 14:23:37 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47980 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229632AbjIRSXf (ORCPT ); Mon, 18 Sep 2023 14:23:35 -0400 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id F2FD0FB; Mon, 18 Sep 2023 11:23:28 -0700 (PDT) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1203BC433C7; Mon, 18 Sep 2023 18:23:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1695061408; bh=/QjMdsE7OVXtJRzPWJ6CSqsPFZENU1J6XX8KyF9J/GI=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=gIdv79p37IBUvVHTp9qfa8DomqJny5lWDbW3kTAFrYFIxtf7N5eIb49p2SDru3xoL tWFIV9eBOb9j6tWbmQscpqCmt6mik+MKsMztmoeMEu7X1qDpcGaS/csrlnQrpUqCa4 WoRUJcDuYMUKJK9N8kR73yQ+fjHb2Q3iIl4SbAwGSibeRuumTK9gmc5Cu0TL4WJlH2 vtTzdW33OjDegR8ltzzfh8sdYp599jDGk1ml4YPNufRPLLvJuQtB1OwWZxoZGxDJpL tu+VOyclL2hMEfowpbHL7SvWHY7ek+Q3r2/Q7gZ9afULh8wbC1YN5YDKmZZoAczj0D PaY8rYBW5mMrQ== Message-ID: <757ecf2d-f544-1ab5-4d34-ece6a0eb1180@kernel.org> Date: Mon, 18 Sep 2023 12:23:27 -0600 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.15.1 Subject: Re: [PATCH V7 0/7] amd-pstate preferred core Content-Language: en-US To: Shuah Khan , Meng Li , "Rafael J . Wysocki" , Huang Rui Cc: linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org, x86@kernel.org, linux-acpi@vger.kernel.org, linux-kselftest@vger.kernel.org, Nathan Fontenot , Deepak Sharma , Alex Deucher , Mario Limonciello , Shimmer Huang , Perry Yuan , Xiaojian Du , Viresh Kumar , Borislav Petkov , Shuah Khan References: <20230918081407.756858-1-li.meng@amd.com> <400a3e3e-4592-c947-a506-6baf1f268224@linuxfoundation.org> From: Shuah In-Reply-To: <400a3e3e-4592-c947-a506-6baf1f268224@linuxfoundation.org> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-acpi@vger.kernel.org On 9/18/23 11:44, Shuah Khan wrote: > On 9/18/23 02:14, Meng Li wrote: >> Hi all: >> >> The core frequency is subjected to the process variation in semiconductors. >> Not all cores are able to reach the maximum frequency respecting the >> infrastructure limits. Consequently, AMD has redefined the concept of >> maximum frequency of a part. This means that a fraction of cores can reach >> maximum frequency. To find the best process scheduling policy for a given >> scenario, OS needs to know the core ordering informed by the platform through >> highest performance capability register of the CPPC interface. >> >> Earlier implementations of amd-pstate preferred core only support a static >> core ranking and targeted performance. Now it has the ability to dynamically >> change the preferred core based on the workload and platform conditions and >> accounting for thermals and aging. >> >> Amd-pstate driver utilizes the functions and data structures provided by >> the ITMT architecture to enable the scheduler to favor scheduling on cores >> which can be get a higher frequency with lower voltage. >> We call it amd-pstate preferred core. >> >> Here sched_set_itmt_core_prio() is called to set priorities and >> sched_set_itmt_support() is called to enable ITMT feature. >> Amd-pstate driver uses the highest performance value to indicate >> the priority of CPU. The higher value has a higher priority. >> >> Amd-pstate driver will provide an initial core ordering at boot time. >> It relies on the CPPC interface to communicate the core ranking to the >> operating system and scheduler to make sure that OS is choosing the cores >> with highest performance firstly for scheduling the process. When amd-pstate >> driver receives a message with the highest performance change, it will >> update the core ranking. >> >> Changes form V6->V7: >> - x86: >> - - Modify kconfig about X86_AMD_PSTATE. >> - cpufreq: amd-pstate: >> - - modify incorrect comments about scheduler_work(). >> - - convert highest_perf data type. >> - - modify preferred core init when cpu init and online. >> - acpi: cppc: >> - - modify link of CPPC highest performance. >> - cpufreq: >> - - modify link of CPPC highest performance changed. >> > > This series in now in linux-kselftest next branch for Linux 6.7-rc1. > > If there are any changes and/or fixes, please send patches on top of > linux-kselftest next branch. > Sorry for the mix-up. Wrong series - my bad. This series isn't in linux-kselftest next. thanks, -- Shuah