From patchwork Thu Aug 20 16:38:01 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: 256993 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=-9.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED autolearn=ham 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 89E8BC433E1 for ; Thu, 20 Aug 2020 16:39:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 711E3208A9 for ; Thu, 20 Aug 2020 16:39:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729983AbgHTQjM (ORCPT ); Thu, 20 Aug 2020 12:39:12 -0400 Received: from cloudserver094114.home.pl ([79.96.170.134]:57068 "EHLO cloudserver094114.home.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728753AbgHTQjL (ORCPT ); Thu, 20 Aug 2020 12:39:11 -0400 Received: from 89-64-87-57.dynamic.chello.pl (89.64.87.57) (HELO kreacher.localnet) by serwer1319399.home.pl (79.96.170.134) with SMTP (IdeaSmtpServer 0.83.459) id a3d0785267e228d1; Thu, 20 Aug 2020 18:39:07 +0200 From: "Rafael J. Wysocki" To: Linux PM Cc: Srinivas Pandruvada , LKML , Doug Smythies Subject: [PATCH 3/4] cpufreq: intel_pstate: Add ->offline and ->online callbacks Date: Thu, 20 Aug 2020 18:38:01 +0200 Message-ID: <1879185.C8Vd3vmt8n@kreacher> In-Reply-To: <2283366.Lr8yYYnyev@kreacher> References: <2283366.Lr8yYYnyev@kreacher> MIME-Version: 1.0 Sender: linux-pm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org From: "Rafael J. Wysocki" Add ->offline and ->online driver callbacksto to do the cleanup before taking a CPU offline and to restore its working configuration when it goes back online, respectively, to avoid invoking the ->init callback on every CPU online which is quite a bit of unnecessary overhead. Define ->offline and ->online so that they can be used in the passive as well as in the active mode and because ->offline will do the majority of ->stop_cpu work, the passive mode does not need that callback any more, so drop it. Signed-off-by: Rafael J. Wysocki --- drivers/cpufreq/intel_pstate.c | 38 ++++++++++++++++++++++++++++------ 1 file changed, 32 insertions(+), 6 deletions(-) diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c index 3d18934fa975..aca0587b176f 100644 --- a/drivers/cpufreq/intel_pstate.c +++ b/drivers/cpufreq/intel_pstate.c @@ -2297,28 +2297,51 @@ static int intel_pstate_verify_policy(struct cpufreq_policy_data *policy) return 0; } -static void intel_cpufreq_stop_cpu(struct cpufreq_policy *policy) +static int intel_pstate_cpu_offline(struct cpufreq_policy *policy) { + pr_debug("CPU %d going offline\n", policy->cpu); + + intel_pstate_exit_perf_limits(policy); + + /* + * If the CPU is an SMT thread and it goes offline with the performance + * settings different from the minimum, it will prevent its sibling + * from getting to lower performance levels, so force the minimum + * performance on CPU offline to prevent that form happening. + */ if (hwp_active) intel_pstate_hwp_force_min_perf(policy->cpu); else intel_pstate_set_min_pstate(all_cpu_data[policy->cpu]); + + return 0; +} + +static int intel_pstate_cpu_online(struct cpufreq_policy *policy) +{ + pr_debug("CPU %d going online\n", policy->cpu); + + intel_pstate_init_acpi_perf_limits(policy); + + if (hwp_active) + wrmsrl_on_cpu(policy->cpu, MSR_HWP_REQUEST, + all_cpu_data[policy->cpu]->hwp_req_cached); + + return 0; } static void intel_pstate_stop_cpu(struct cpufreq_policy *policy) { - pr_debug("CPU %d exiting\n", policy->cpu); + pr_debug("CPU %d stopping\n", policy->cpu); intel_pstate_clear_update_util_hook(policy->cpu); if (hwp_active) intel_pstate_hwp_save_state(policy); - - intel_cpufreq_stop_cpu(policy); } static int intel_pstate_cpu_exit(struct cpufreq_policy *policy) { - intel_pstate_exit_perf_limits(policy); + pr_debug("CPU %d exiting\n", policy->cpu); policy->fast_switch_possible = false; @@ -2398,6 +2421,8 @@ static struct cpufreq_driver intel_pstate = { .init = intel_pstate_cpu_init, .exit = intel_pstate_cpu_exit, .stop_cpu = intel_pstate_stop_cpu, + .offline = intel_pstate_cpu_offline, + .online = intel_pstate_cpu_online, .update_limits = intel_pstate_update_limits, .name = "intel_pstate", }; @@ -2652,7 +2677,8 @@ static struct cpufreq_driver intel_cpufreq = { .fast_switch = intel_cpufreq_fast_switch, .init = intel_cpufreq_cpu_init, .exit = intel_cpufreq_cpu_exit, - .stop_cpu = intel_cpufreq_stop_cpu, + .offline = intel_pstate_cpu_offline, + .online = intel_pstate_cpu_online, .update_limits = intel_pstate_update_limits, .name = "intel_cpufreq", };