From patchwork Thu Nov 5 18:23:34 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: 319676 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=-6.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED 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 5CDB5C5517A for ; Thu, 5 Nov 2020 18:25:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0CBB62151B for ; Thu, 5 Nov 2020 18:25:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731758AbgKESZX (ORCPT ); Thu, 5 Nov 2020 13:25:23 -0500 Received: from cloudserver094114.home.pl ([79.96.170.134]:44024 "EHLO cloudserver094114.home.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726729AbgKESZW (ORCPT ); Thu, 5 Nov 2020 13:25:22 -0500 Received: from 89-64-88-191.dynamic.chello.pl (89.64.88.191) (HELO kreacher.localnet) by serwer1319399.home.pl (79.96.170.134) with SMTP (IdeaSmtpServer 0.83.514) id eb3d0aa0ebe85b20; Thu, 5 Nov 2020 19:25:19 +0100 From: "Rafael J. Wysocki" To: Linux PM Cc: "Rafael J. Wysocki" , Viresh Kumar , Srinivas Pandruvada , Zhang Rui , LKML Subject: [PATCH 1/2] cpufreq: Introduce target min and max frequency hints Date: Thu, 05 Nov 2020 19:23:34 +0100 Message-ID: <2233690.N3OVLkotou@kreacher> In-Reply-To: <7417968.Ghue05m4RV@kreacher> References: <7417968.Ghue05m4RV@kreacher> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org From: Rafael J. Wysocki Some cpufreq drivers, like intel_pstate (in the passive mode with HWP enabled) or the CPPC driver, take the "target frequency" coming from the governor as a hint to pass to the hardware rather than the exact value to apply. Then, the hardware may choose to run at whatever performance point it regards as appropriate, given the hint and some other data available to it. Of course, the performance point chosen by the hardware should stay within the policy min and max limits, but in some cases it may be necessary to request the hardware to limit the range of performance points to consider beyond that. For example, if the powersave governor is in use, it attempts to make the hardware run at the policy min frequency, but that may not actually work if the hardware thinks that it has a reason to run faster and the policy max limit is above the policy min. In those cases, it is useful to pass additional information to the driver to indicate that it should tell the hardware to consider a narrower range of performance points, so add two new fields, target_min and target_max, to struct cpufreq_policy for this purpose and make the powersave and performance governors set them to indicate that the CPU is expected to run exactly at the given frequency (the policy min or max, respectively). Signed-off-by: Rafael J. Wysocki --- drivers/cpufreq/cpufreq.c | 3 +++ drivers/cpufreq/cpufreq_performance.c | 4 ++++ drivers/cpufreq/cpufreq_powersave.c | 4 ++++ include/linux/cpufreq.h | 16 ++++++++++++++++ 4 files changed, 27 insertions(+) Index: linux-pm/include/linux/cpufreq.h =================================================================== --- linux-pm.orig/include/linux/cpufreq.h +++ linux-pm/include/linux/cpufreq.h @@ -63,6 +63,8 @@ struct cpufreq_policy { unsigned int min; /* in kHz */ unsigned int max; /* in kHz */ + unsigned int target_min; /* in kHz */ + unsigned int target_max; /* in kHz */ unsigned int cur; /* in kHz, only needed if cpufreq * governors are used */ unsigned int suspend_freq; /* freq to set during suspend */ Index: linux-pm/drivers/cpufreq/cpufreq.c =================================================================== --- linux-pm.orig/drivers/cpufreq/cpufreq.c +++ linux-pm/drivers/cpufreq/cpufreq.c @@ -2272,6 +2272,9 @@ static int cpufreq_init_governor(struct pr_debug("%s: for CPU %u\n", __func__, policy->cpu); + policy->target_min = policy->cpuinfo.min_freq; + policy->target_max = policy->cpuinfo.max_freq; + if (policy->governor->init) { ret = policy->governor->init(policy); if (ret) { Index: linux-pm/drivers/cpufreq/cpufreq_performance.c =================================================================== --- linux-pm.orig/drivers/cpufreq/cpufreq_performance.c +++ linux-pm/drivers/cpufreq/cpufreq_performance.c @@ -14,6 +14,10 @@ static void cpufreq_gov_performance_limits(struct cpufreq_policy *policy) { pr_debug("setting to %u kHz\n", policy->max); + + policy->target_min = policy->max; + policy->target_max = policy->max; + __cpufreq_driver_target(policy, policy->max, CPUFREQ_RELATION_H); } Index: linux-pm/drivers/cpufreq/cpufreq_powersave.c =================================================================== --- linux-pm.orig/drivers/cpufreq/cpufreq_powersave.c +++ linux-pm/drivers/cpufreq/cpufreq_powersave.c @@ -14,6 +14,10 @@ static void cpufreq_gov_powersave_limits(struct cpufreq_policy *policy) { pr_debug("setting to %u kHz\n", policy->min); + + policy->target_min = policy->min; + policy->target_max = policy->min; + __cpufreq_driver_target(policy, policy->min, CPUFREQ_RELATION_L); } From patchwork Thu Nov 5 18:25:10 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: 319677 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=-6.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED 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 D015CC4741F for ; Thu, 5 Nov 2020 18:25:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 787D7221FE for ; Thu, 5 Nov 2020 18:25:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727275AbgKESZU (ORCPT ); Thu, 5 Nov 2020 13:25:20 -0500 Received: from cloudserver094114.home.pl ([79.96.170.134]:65252 "EHLO cloudserver094114.home.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726214AbgKESZU (ORCPT ); Thu, 5 Nov 2020 13:25:20 -0500 Received: from 89-64-88-191.dynamic.chello.pl (89.64.88.191) (HELO kreacher.localnet) by serwer1319399.home.pl (79.96.170.134) with SMTP (IdeaSmtpServer 0.83.514) id 4ff6dc8dccf7dc57; Thu, 5 Nov 2020 19:25:18 +0100 From: "Rafael J. Wysocki" To: Linux PM Cc: "Rafael J. Wysocki" , Viresh Kumar , Srinivas Pandruvada , Zhang Rui , LKML Subject: [PATCH 2/2] cpufreq: intel_pstate: Take target_min and target_max into account Date: Thu, 05 Nov 2020 19:25:10 +0100 Message-ID: <3200924.ySlC381xRO@kreacher> In-Reply-To: <7417968.Ghue05m4RV@kreacher> References: <7417968.Ghue05m4RV@kreacher> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org From: Rafael J. Wysocki Make the intel_pstate driver take the new target_min and target_max cpufreq policy parameters into accout when it operates in the passive mode with HWP enabled, so as to fix the "powersave" governor behavior in that case (currently, HWP is allowed to scale the performance all the way up to the policy max limit when the "powersave" governor is used, but it should be contrained to the policy min limit then). Signed-off-by: Rafael J. Wysocki --- drivers/cpufreq/intel_pstate.c | 32 ++++++++++++++++++++++---------- 1 file changed, 22 insertions(+), 10 deletions(-) Index: linux-pm/drivers/cpufreq/intel_pstate.c =================================================================== --- linux-pm.orig/drivers/cpufreq/intel_pstate.c +++ linux-pm/drivers/cpufreq/intel_pstate.c @@ -2527,7 +2527,7 @@ static void intel_cpufreq_trace(struct c } static void intel_cpufreq_adjust_hwp(struct cpudata *cpu, u32 target_pstate, - bool fast_switch) + u32 target_max, bool fast_switch) { u64 prev = READ_ONCE(cpu->hwp_req_cached), value = prev; @@ -2539,7 +2539,7 @@ static void intel_cpufreq_adjust_hwp(str * field in it, so opportunistically update the max too if needed. */ value &= ~HWP_MAX_PERF(~0L); - value |= HWP_MAX_PERF(cpu->max_perf_ratio); + value |= HWP_MAX_PERF(target_max); if (value == prev) return; @@ -2562,19 +2562,31 @@ static void intel_cpufreq_adjust_perf_ct pstate_funcs.get_val(cpu, target_pstate)); } -static int intel_cpufreq_update_pstate(struct cpudata *cpu, int target_pstate, - bool fast_switch) +static int intel_cpufreq_update_pstate(struct cpufreq_policy *policy, + int target_pstate, bool fast_switch) { + struct cpudata *cpu = all_cpu_data[policy->cpu]; int old_pstate = cpu->pstate.current_pstate; - target_pstate = intel_pstate_prepare_request(cpu, target_pstate); if (hwp_active) { - intel_cpufreq_adjust_hwp(cpu, target_pstate, fast_switch); - cpu->pstate.current_pstate = target_pstate; + int min_pstate = max(cpu->pstate.min_pstate, cpu->min_perf_ratio); + int max_pstate = max(min_pstate, cpu->max_perf_ratio); + int target_min = DIV_ROUND_UP(policy->target_min, + cpu->pstate.scaling); + int target_max = policy->target_max / cpu->pstate.scaling; + + target_min = clamp_t(int, target_min, min_pstate, max_pstate); + target_max = clamp_t(int, target_max, min_pstate, max_pstate); + + target_pstate = clamp_t(int, target_pstate, target_min, target_max); + + intel_cpufreq_adjust_hwp(cpu, target_pstate, target_max, fast_switch); } else if (target_pstate != old_pstate) { + target_pstate = intel_pstate_prepare_request(cpu, target_pstate); + intel_cpufreq_adjust_perf_ctl(cpu, target_pstate, fast_switch); - cpu->pstate.current_pstate = target_pstate; } + cpu->pstate.current_pstate = target_pstate; intel_cpufreq_trace(cpu, fast_switch ? INTEL_PSTATE_TRACE_FAST_SWITCH : INTEL_PSTATE_TRACE_TARGET, old_pstate); @@ -2609,7 +2621,7 @@ static int intel_cpufreq_target(struct c break; } - target_pstate = intel_cpufreq_update_pstate(cpu, target_pstate, false); + target_pstate = intel_cpufreq_update_pstate(policy, target_pstate, false); freqs.new = target_pstate * cpu->pstate.scaling; @@ -2628,7 +2640,7 @@ static unsigned int intel_cpufreq_fast_s target_pstate = DIV_ROUND_UP(target_freq, cpu->pstate.scaling); - target_pstate = intel_cpufreq_update_pstate(cpu, target_pstate, true); + target_pstate = intel_cpufreq_update_pstate(policy, target_pstate, true); return target_pstate * cpu->pstate.scaling; }