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Wysocki" X-Patchwork-Id: 10884555 X-Patchwork-Delegate: rjw@sisk.pl Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 931E913B5 for ; Wed, 3 Apr 2019 22:10:52 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 7B9022897F for ; Wed, 3 Apr 2019 22:10:52 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 6FADE28986; Wed, 3 Apr 2019 22:10:52 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id E0FE628984 for ; Wed, 3 Apr 2019 22:10:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726640AbfDCWKr convert rfc822-to-8bit (ORCPT ); Wed, 3 Apr 2019 18:10:47 -0400 Received: from cloudserver094114.home.pl ([79.96.170.134]:52436 "EHLO cloudserver094114.home.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726167AbfDCWKh (ORCPT ); Wed, 3 Apr 2019 18:10:37 -0400 Received: from 79.184.254.219.ipv4.supernova.orange.pl (79.184.254.219) (HELO aspire.rjw.lan) by serwer1319399.home.pl (79.96.170.134) with SMTP (IdeaSmtpServer 0.83.213) id 1e34c89d64ffa71c; Thu, 4 Apr 2019 00:10:34 +0200 From: "Rafael J. Wysocki" To: Linux PM Cc: LKML , Linux ACPI , Linux Documentation , Jonathan Corbet , Srinivas Pandruvada , Viresh Kumar Subject: [PATCH 1/4] cpufreq: intel_pstate: Documentation: Add references sections Date: Thu, 04 Apr 2019 00:03:30 +0200 Message-ID: <2330972.sZBoMHM721@aspire.rjw.lan> In-Reply-To: <4546107.fVFrecLk33@aspire.rjw.lan> References: <4546107.fVFrecLk33@aspire.rjw.lan> MIME-Version: 1.0 Sender: linux-acpi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-acpi@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Rafael J. Wysocki Add separate refereces sections to the cpufreq.rst and intel_pstate.rst documents under admin-quide/pm and list the references to external documentation in there. Update the ACPI specification URL while at it. Signed-off-by: Rafael J. Wysocki --- Documentation/admin-guide/pm/cpufreq.rst | 10 +++++++--- Documentation/admin-guide/pm/intel_pstate.rst | 25 ++++++++++++++++--------- 2 files changed, 23 insertions(+), 12 deletions(-) Index: linux-pm/Documentation/admin-guide/pm/intel_pstate.rst =================================================================== --- linux-pm.orig/Documentation/admin-guide/pm/intel_pstate.rst +++ linux-pm/Documentation/admin-guide/pm/intel_pstate.rst @@ -20,11 +20,10 @@ you have not done that yet.] For the processors supported by ``intel_pstate``, the P-state concept is broader than just an operating frequency or an operating performance point (see the -`LinuxCon Europe 2015 presentation by Kristen Accardi `_ for more +LinuxCon Europe 2015 presentation by Kristen Accardi [1]_ for more information about that). For this reason, the representation of P-states used by ``intel_pstate`` internally follows the hardware specification (for details -refer to `Intel® 64 and IA-32 Architectures Software Developer’s Manual -Volume 3: System Programming Guide `_). However, the ``CPUFreq`` core +refer to Intel Software Developer’s Manual [2]_). However, the ``CPUFreq`` core uses frequencies for identifying operating performance points of CPUs and frequencies are involved in the user space interface exposed by it, so ``intel_pstate`` maps its internal representation of P-states to frequencies too @@ -561,9 +560,9 @@ or to pin every task potentially sensiti On the majority of systems supported by ``intel_pstate``, the ACPI tables provided by the platform firmware contain ``_PSS`` objects returning information -that can be used for CPU performance scaling (refer to the `ACPI specification`_ -for details on the ``_PSS`` objects and the format of the information returned -by them). +that can be used for CPU performance scaling (refer to the ACPI specification +[3]_ for details on the ``_PSS`` objects and the format of the information +returned by them). The information returned by the ACPI ``_PSS`` objects is used by the ``acpi-cpufreq`` scaling driver. On systems supported by ``intel_pstate`` @@ -728,6 +727,14 @@ P-state is called, the ``ftrace`` filter -0 [000] ..s. 2537.654843: intel_pstate_set_pstate <-intel_pstate_timer_func -.. _LCEU2015: http://events.linuxfoundation.org/sites/events/files/slides/LinuxConEurope_2015.pdf -.. _SDM: http://www.intel.com/content/www/us/en/architecture-and-technology/64-ia-32-architectures-software-developer-system-programming-manual-325384.html -.. _ACPI specification: http://www.uefi.org/sites/default/files/resources/ACPI_6_1.pdf +References +========== + +.. [1] Kristen Accardi, *Balancing Power and Performance in the Linux Kernel*, + http://events.linuxfoundation.org/sites/events/files/slides/LinuxConEurope_2015.pdf + +.. [2] *Intel® 64 and IA-32 Architectures Software Developer’s Manual Volume 3: System Programming Guide*, + http://www.intel.com/content/www/us/en/architecture-and-technology/64-ia-32-architectures-software-developer-system-programming-manual-325384.html + +.. [3] *Advanced Configuration and Power Interface Specification*, + https://uefi.org/sites/default/files/resources/ACPI_6_3_final_Jan30.pdf Index: linux-pm/Documentation/admin-guide/pm/cpufreq.rst =================================================================== --- linux-pm.orig/Documentation/admin-guide/pm/cpufreq.rst +++ linux-pm/Documentation/admin-guide/pm/cpufreq.rst @@ -396,8 +396,8 @@ RT or deadline scheduling classes, the g the allowed maximum (that is, the ``scaling_max_freq`` policy limit). In turn, if it is invoked by the CFS scheduling class, the governor will use the Per-Entity Load Tracking (PELT) metric for the root control group of the -given CPU as the CPU utilization estimate (see the `Per-entity load tracking`_ -LWN.net article for a description of the PELT mechanism). Then, the new +given CPU as the CPU utilization estimate (see the *Per-entity load tracking* +LWN.net article [1]_ for a description of the PELT mechanism). Then, the new CPU frequency to apply is computed in accordance with the formula f = 1.25 * ``f_0`` * ``util`` / ``max`` @@ -698,4 +698,8 @@ hardware feature (e.g. all Intel ones), :c:macro:`CONFIG_X86_ACPI_CPUFREQ_CPB` configuration option is set. -.. _Per-entity load tracking: https://lwn.net/Articles/531853/ +References +========== + +.. [1] Jonathan Corbet, *Per-entity load tracking*, + https://lwn.net/Articles/531853/