From patchwork Mon Aug 24 13:40:54 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: 256958 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=-6.8 required=3.0 tests=BAYES_00, 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 6BEB9C433DF for ; Mon, 24 Aug 2020 13:41:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 49C5921741 for ; Mon, 24 Aug 2020 13:41:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727824AbgHXNk7 (ORCPT ); Mon, 24 Aug 2020 09:40:59 -0400 Received: from cloudserver094114.home.pl ([79.96.170.134]:64224 "EHLO cloudserver094114.home.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727116AbgHXNk5 (ORCPT ); Mon, 24 Aug 2020 09:40:57 -0400 Received: from 89-64-88-199.dynamic.chello.pl (89.64.88.199) (HELO kreacher.localnet) by serwer1319399.home.pl (79.96.170.134) with SMTP (IdeaSmtpServer 0.83.459) id 8cbe13510595119e; Mon, 24 Aug 2020 15:40:54 +0200 From: "Rafael J. Wysocki" To: Doug Smythies Cc: 'Srinivas Pandruvada' , 'LKML' , 'Linux PM' Subject: [PATCH v2 3/4] cpufreq: intel_pstate: Add ->offline and ->online callbacks Date: Mon, 24 Aug 2020 15:40:54 +0200 Message-ID: <1620790.MIbp4yWDbA@kreacher> In-Reply-To: <000501d6781d$c953def0$5bfb9cd0$@net> References: <2283366.Lr8yYYnyev@kreacher> <1879185.C8Vd3vmt8n@kreacher> <000501d6781d$c953def0$5bfb9cd0$@net> MIME-Version: 1.0 Sender: linux-pm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org On Saturday, August 22, 2020 2:47:16 AM CEST Doug Smythies wrote: > Hi Rafael, > > Just annoying typo type feedback. Thanks! Please find a corrected patch below. Cheers! --- From: Rafael J. Wysocki Subject: [PATCH] cpufreq: intel_pstate: Add ->offline and ->online callbacks Add ->offline and ->online driver callbacks to prepare for 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 mode 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(-) Index: linux-pm/drivers/cpufreq/intel_pstate.c =================================================================== --- linux-pm.orig/drivers/cpufreq/intel_pstate.c +++ linux-pm/drivers/cpufreq/intel_pstate.c @@ -2297,28 +2297,51 @@ static int intel_pstate_verify_policy(st 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 from 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_pstat .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_cpufr .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", };