From patchwork Thu Aug 20 16:36:22 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: 256992 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=-9.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS 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 4D4E7C433DF for ; Thu, 20 Aug 2020 16:39:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 32EFC2054F for ; Thu, 20 Aug 2020 16:39:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729997AbgHTQjN (ORCPT ); Thu, 20 Aug 2020 12:39:13 -0400 Received: from cloudserver094114.home.pl ([79.96.170.134]:63698 "EHLO cloudserver094114.home.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729979AbgHTQjL (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 1b514db4d289dfba; Thu, 20 Aug 2020 18:39:09 +0200 From: "Rafael J. Wysocki" To: Linux PM Cc: Srinivas Pandruvada , LKML , Doug Smythies Subject: [PATCH 1/4] cpufreq: intel_pstate: Refuse to turn off with HWP enabled Date: Thu, 20 Aug 2020 18:36:22 +0200 Message-ID: <4103589.WxEslRmDz8@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" After commit f6ebbcf08f37 ("cpufreq: intel_pstate: Implement passive mode with HWP enabled") it is possible to change the driver status to "off" via sysfs with HWP enabled, which effectively causes the driver to unregister itself, but HWP remains active and it forces the minimum performance, so even if another cpufreq driver is loaded, it will not be able to control the CPU frequency. For this reason, make the driver refuse to change the status to "off" with HWP enabled. Signed-off-by: Rafael J. Wysocki --- drivers/cpufreq/intel_pstate.c | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-) diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c index e0220a6fbc69..bcda1e700a73 100644 --- a/drivers/cpufreq/intel_pstate.c +++ b/drivers/cpufreq/intel_pstate.c @@ -2716,9 +2716,15 @@ static int intel_pstate_update_status(const char *buf, size_t size) { int ret; - if (size == 3 && !strncmp(buf, "off", size)) - return intel_pstate_driver ? - intel_pstate_unregister_driver() : -EINVAL; + if (size == 3 && !strncmp(buf, "off", size)) { + if (!intel_pstate_driver) + return -EINVAL; + + if (hwp_active) + return -EBUSY; + + return intel_pstate_unregister_driver(); + } if (size == 6 && !strncmp(buf, "active", size)) { if (intel_pstate_driver) { 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", }; From patchwork Thu Aug 20 16:38:40 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: 256991 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=unavailable 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 A2518C433E8 for ; Thu, 20 Aug 2020 16:39:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8ADDE2054F for ; Thu, 20 Aug 2020 16:39:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729989AbgHTQjM (ORCPT ); Thu, 20 Aug 2020 12:39:12 -0400 Received: from cloudserver094114.home.pl ([79.96.170.134]:41938 "EHLO cloudserver094114.home.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728987AbgHTQjL (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 48e50a6e30a2fd8e; Thu, 20 Aug 2020 18:39:06 +0200 From: "Rafael J. Wysocki" To: Linux PM Cc: Srinivas Pandruvada , LKML , Doug Smythies Subject: [PATCH 4/4] cpufreq: intel_pstate: Free memory only when turning off Date: Thu, 20 Aug 2020 18:38:40 +0200 Message-ID: <5545992.MujegtMJko@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" When intel_pstate switches the operation mode from "active" to "passive" or the other way around, freeing its data structures representing CPUs and allocating them again from scratch is not necessary and wasteful. Moreover, if these data structures are preserved, the cached HWP Request MSR value from there may be written to the MSR to start with to reinitialize it and help to restore the EPP value set previously (it is set to 0xFF when CPUs go offline to allow their SMT siblings to use the full range of EPP values and that also happens when the driver gets unregistered). Accordingly, modify the driver to only do a full cleanup on driver object registration errors and when its status is changed to "off" via sysfs and to write the cached HWP Request MSR value back to the MSR on CPU init if the data structure representing the given CPU is still there. Signed-off-by: Rafael J. Wysocki --- drivers/cpufreq/intel_pstate.c | 51 +++++++++++++--------------------- 1 file changed, 19 insertions(+), 32 deletions(-) diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c index aca0587b176f..a7c6491f2b4a 100644 --- a/drivers/cpufreq/intel_pstate.c +++ b/drivers/cpufreq/intel_pstate.c @@ -2091,30 +2091,32 @@ static int intel_pstate_init_cpu(unsigned int cpunum) cpu = all_cpu_data[cpunum]; - if (!cpu) { + if (cpu) { + if (hwp_active) + wrmsrl_on_cpu(cpunum, MSR_HWP_REQUEST, + cpu->hwp_req_cached); + } else { cpu = kzalloc(sizeof(*cpu), GFP_KERNEL); if (!cpu) return -ENOMEM; all_cpu_data[cpunum] = cpu; + cpu->cpu = cpunum; + cpu->epp_default = -EINVAL; cpu->epp_powersave = -EINVAL; cpu->epp_saved = -EINVAL; - } - - cpu = all_cpu_data[cpunum]; - cpu->cpu = cpunum; + if (hwp_active) { + const struct x86_cpu_id *id; - if (hwp_active) { - const struct x86_cpu_id *id; + intel_pstate_hwp_enable(cpu); - intel_pstate_hwp_enable(cpu); - - id = x86_match_cpu(intel_pstate_hwp_boost_ids); - if (id && intel_pstate_acpi_pm_profile_server()) - hwp_boost = true; + id = x86_match_cpu(intel_pstate_hwp_boost_ids); + if (id && intel_pstate_acpi_pm_profile_server()) + hwp_boost = true; + } } intel_pstate_get_cpu_pstates(cpu); @@ -2701,9 +2703,6 @@ static void intel_pstate_driver_cleanup(void) } put_online_cpus(); - if (intel_pstate_driver == &intel_pstate) - intel_pstate_sysfs_hide_hwp_dynamic_boost(); - intel_pstate_driver = NULL; } @@ -2729,14 +2728,6 @@ static int intel_pstate_register_driver(struct cpufreq_driver *driver) return 0; } -static int intel_pstate_unregister_driver(void) -{ - cpufreq_unregister_driver(intel_pstate_driver); - intel_pstate_driver_cleanup(); - - return 0; -} - static ssize_t intel_pstate_show_status(char *buf) { if (!intel_pstate_driver) @@ -2748,8 +2739,6 @@ static ssize_t intel_pstate_show_status(char *buf) static int intel_pstate_update_status(const char *buf, size_t size) { - int ret; - if (size == 3 && !strncmp(buf, "off", size)) { if (!intel_pstate_driver) return -EINVAL; @@ -2757,7 +2746,8 @@ static int intel_pstate_update_status(const char *buf, size_t size) if (hwp_active) return -EBUSY; - return intel_pstate_unregister_driver(); + cpufreq_unregister_driver(intel_pstate_driver); + intel_pstate_driver_cleanup(); } if (size == 6 && !strncmp(buf, "active", size)) { @@ -2765,9 +2755,7 @@ static int intel_pstate_update_status(const char *buf, size_t size) if (intel_pstate_driver == &intel_pstate) return 0; - ret = intel_pstate_unregister_driver(); - if (ret) - return ret; + cpufreq_unregister_driver(intel_pstate_driver); } return intel_pstate_register_driver(&intel_pstate); @@ -2778,9 +2766,8 @@ static int intel_pstate_update_status(const char *buf, size_t size) if (intel_pstate_driver == &intel_cpufreq) return 0; - ret = intel_pstate_unregister_driver(); - if (ret) - return ret; + cpufreq_unregister_driver(intel_pstate_driver); + intel_pstate_sysfs_hide_hwp_dynamic_boost(); } return intel_pstate_register_driver(&intel_cpufreq);