From patchwork Thu Jan 30 14:46:24 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Rafael J. Wysocki" X-Patchwork-Id: 194439 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=-3.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS 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 A35DDC35248 for ; Thu, 30 Jan 2020 14:47:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7BD5D24682 for ; Thu, 30 Jan 2020 14:47:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727416AbgA3Orm (ORCPT ); Thu, 30 Jan 2020 09:47:42 -0500 Received: from cloudserver094114.home.pl ([79.96.170.134]:53550 "EHLO cloudserver094114.home.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727304AbgA3Ork (ORCPT ); Thu, 30 Jan 2020 09:47:40 -0500 Received: from 79.184.253.19.ipv4.supernova.orange.pl (79.184.253.19) (HELO kreacher.localnet) by serwer1319399.home.pl (79.96.170.134) with SMTP (IdeaSmtpServer 0.83.341) id 5628b28504f96a71; Thu, 30 Jan 2020 15:47:38 +0100 From: "Rafael J. Wysocki" To: Linux PM Cc: Linux ACPI , LKML , Len Brown , Zhang Rui , David Box , Artem Bityutskiy , "Rafael J. Wysocki" Subject: [PATCH 1/2] intel_idle: Introduce 'use_acpi' module parameter Date: Thu, 30 Jan 2020 15:46:24 +0100 Message-ID: <5626578.OFR1oUKyPK@kreacher> In-Reply-To: <1720216.0Jr2BLnqKp@kreacher> References: <1720216.0Jr2BLnqKp@kreacher> MIME-Version: 1.0 Sender: linux-acpi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-acpi@vger.kernel.org From: Rafael J. Wysocki For diagnostics, it is generally useful to be able to make intel_idle take the system's ACPI tables into consideration even if that is not required for the processor model in there, so introduce a new module parameter, 'use_acpi', to make that happen and update the documentation to cover it. While at it, fix the 'no_acpi' module parameter name in the documentation. Signed-off-by: Rafael J. Wysocki --- Documentation/admin-guide/pm/intel_idle.rst | 13 +++++++++---- drivers/idle/intel_idle.c | 11 +++++++++-- 2 files changed, 18 insertions(+), 6 deletions(-) Index: linux-pm/drivers/idle/intel_idle.c =================================================================== --- linux-pm.orig/drivers/idle/intel_idle.c +++ linux-pm/drivers/idle/intel_idle.c @@ -1131,6 +1131,10 @@ static bool no_acpi __read_mostly; module_param(no_acpi, bool, 0444); MODULE_PARM_DESC(no_acpi, "Do not use ACPI _CST for building the idle states list"); +static bool use_acpi __read_mostly; /* No effect if no_acpi is set. */ +module_param(use_acpi, bool, 0444); +MODULE_PARM_DESC(use_acpi, "Use ACPI _CST for building the idle states list"); + static struct acpi_processor_power acpi_state_table __initdata; /** @@ -1258,6 +1262,8 @@ static bool __init intel_idle_off_by_def return true; } #else /* !CONFIG_ACPI_PROCESSOR_CSTATE */ +#define use_acpi (false) + static inline bool intel_idle_acpi_cst_extract(void) { return false; } static inline void intel_idle_init_cstates_acpi(struct cpuidle_driver *drv) { } static inline bool intel_idle_off_by_default(u32 mwait_hint) { return false; } @@ -1460,7 +1466,8 @@ static void __init intel_idle_init_cstat /* Structure copy. */ drv->states[drv->state_count] = cpuidle_state_table[cstate]; - if (icpu->use_acpi && intel_idle_off_by_default(mwait_hint) && + if ((icpu->use_acpi || use_acpi) && + intel_idle_off_by_default(mwait_hint) && !(cpuidle_state_table[cstate].flags & CPUIDLE_FLAG_ALWAYS_ENABLE)) drv->states[drv->state_count].flags |= CPUIDLE_FLAG_OFF; @@ -1607,7 +1614,7 @@ static int __init intel_idle_init(void) icpu = (const struct idle_cpu *)id->driver_data; if (icpu) { cpuidle_state_table = icpu->state_table; - if (icpu->use_acpi) + if (icpu->use_acpi || use_acpi) intel_idle_acpi_cst_extract(); } else if (!intel_idle_acpi_cst_extract()) { return -ENODEV; Index: linux-pm/Documentation/admin-guide/pm/intel_idle.rst =================================================================== --- linux-pm.orig/Documentation/admin-guide/pm/intel_idle.rst +++ linux-pm/Documentation/admin-guide/pm/intel_idle.rst @@ -60,6 +60,9 @@ of the system. The former are always us recognized by ``intel_idle`` and the latter are used if that is required for the given processor model (which is the case for all server processor models recognized by ``intel_idle``) or if the processor model is not recognized. +[There is a module parameter that can be used to make the driver use the ACPI +tables with any processor model recognized by it; see +`below `_.] If the ACPI tables are going to be used for building the list of available idle states, ``intel_idle`` first looks for a ``_CST`` object under one of the ACPI @@ -165,7 +168,7 @@ and ``idle=nomwait``. If any of them is ``MWAIT`` instruction is not allowed to be used, so the initialization of ``intel_idle`` will fail. -Apart from that there are two module parameters recognized by ``intel_idle`` +Apart from that there are three module parameters recognized by ``intel_idle`` itself that can be set via the kernel command line (they cannot be updated via sysfs, so that is the only way to change their values). @@ -186,9 +189,11 @@ QoS) feature can be used to prevent ``CP even if they have been enumerated (see :ref:`cpu-pm-qos` in :doc:`cpuidle`). Setting ``max_cstate`` to 0 causes the ``intel_idle`` initialization to fail. -The ``noacpi`` module parameter (which is recognized by ``intel_idle`` if the -kernel has been configured with ACPI support), can be set to make the driver -ignore the system's ACPI tables entirely (it is unset by default). +The ``no_acpi`` and ``use_acpi`` module parameters (recognized by ``intel_idle`` +if the kernel has been configured with ACPI support) can be set to make the +driver ignore the system's ACPI tables entirely or use them for all of the +recognized processor models, respectively (they both are unset by default and +``use_acpi`` has no effect if ``no_acpi`` is set). .. _intel-idle-core-and-package-idle-states: