From mboxrd@z Thu Jan 1 00:00:00 1970 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=-18.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT 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 2FCA5C6379D for ; Thu, 19 Nov 2020 07:38:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C63A122260 for ; Thu, 19 Nov 2020 07:38:40 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b="oUjbWw2j" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726355AbgKSHi0 (ORCPT ); Thu, 19 Nov 2020 02:38:26 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56878 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725816AbgKSHiZ (ORCPT ); Thu, 19 Nov 2020 02:38:25 -0500 Received: from mail-pf1-x442.google.com (mail-pf1-x442.google.com [IPv6:2607:f8b0:4864:20::442]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5E5C0C0613D4 for ; Wed, 18 Nov 2020 23:38:25 -0800 (PST) Received: by mail-pf1-x442.google.com with SMTP id c66so3640425pfa.4 for ; Wed, 18 Nov 2020 23:38:25 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=oHrMQUbqDwzagP4Y2oPS+XW/6aunUOQ8w5HkGn8duRY=; b=oUjbWw2jWK7s8CbG+dI6Vb3FSb781vdJfwgeSbaTKtRlOu3FgcCjvfWACtGf0Ig0bv 6hw9N/4aSSmPjWVYLW+LKHFCV1EF/r34gP/FzYODhBQTO2zRcv6oOvY8pq2WHYqa96js dNsXgB69ecU6oug+UWWJ8LxweXgtRfWMw4w4JXjEbSNxX4bbr2WO/r9Zrr72H09qJCWZ L4mtVyBrsoe5V3TNmeiAfCGHceqls+7QXfvXAAfBM0kW2WsqWT4OS/HblYu/Eyyc618e lcunYNy/PSjuK6kPSPp7Xa4+eB2AEwDsQ/kGYJuQ/UcSDccsBjNVmMfmzZch5naRCEoK 7gEw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=oHrMQUbqDwzagP4Y2oPS+XW/6aunUOQ8w5HkGn8duRY=; b=GM3BbptNSjr+9H/79NW3dM403Je8nD06UK+33MLc+RDgVM6Xs8onSgy2kKW9qpajju B588hTCAgOobFhZVGa11wibcdlAIxEBx3zIMRD/dVw5KUACiF/ik6g13ZzKSg4DBy5pj Myv1gMu7+l365vaLhLIoEetDBWEl4RH2xpsLdLI1FpPkYcO8iBe0yafAFhtYStZlPP9/ 3bvKGgHevedYr8yh9h86WHQ/Uu+AIEkh3f5fmR/vazH0yxYi9YH/STSnEV/Umm1+frMi feWuiBhx6we98XowlB1Fw5Ig/55FocGwXWFuXpOR5o2bw0XLXOUggTQnN5CV6+zEAe9z YTUQ== X-Gm-Message-State: AOAM533IMoUAlTfIqsaUp+dDlzECtcId+Gwv4yMA7pCYHg+NmTRRbqjf 3bEaaNwHlR1s04+WFVPOA1yGVg== X-Google-Smtp-Source: ABdhPJx7e6rdZWHbAN1nX6uwJL8arAmZmx68HTtHZ9boVJp869RlJjcDSGgc58cdq9JtSdT/BRTaYg== X-Received: by 2002:aa7:8481:0:b029:18b:f647:45f7 with SMTP id u1-20020aa784810000b029018bf64745f7mr8008662pfn.58.1605771504870; Wed, 18 Nov 2020 23:38:24 -0800 (PST) Received: from localhost ([122.172.12.172]) by smtp.gmail.com with ESMTPSA id kb12sm5157016pjb.2.2020.11.18.23.38.23 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Wed, 18 Nov 2020 23:38:24 -0800 (PST) From: Viresh Kumar To: Ingo Molnar , Peter Zijlstra , Vincent Guittot , Amit Daniel Kachhap , Daniel Lezcano , Viresh Kumar , Javi Merino , Zhang Rui , Amit Kucheria Cc: linux-kernel@vger.kernel.org, Quentin Perret , Lukasz Luba , linux-pm@vger.kernel.org Subject: [PATCH V3 2/2] thermal: cpufreq_cooling: Reuse sched_cpu_util() for SMP platforms Date: Thu, 19 Nov 2020 13:08:08 +0530 Message-Id: <1fa9994395764ba19cfe6240d8b3c1ce390e8f82.1605770951.git.viresh.kumar@linaro.org> X-Mailer: git-send-email 2.25.0.rc1.19.g042ed3e048af In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Several parts of the kernel are already using the effective CPU utilization (as seen by the scheduler) to get the current load on the CPU, do the same here instead of depending on the idle time of the CPU, which isn't that accurate comparatively. This is also the right thing to do as it makes the cpufreq governor (schedutil) align better with the cpufreq_cooling driver, as the power requested by cpufreq_cooling governor will exactly match the next frequency requested by the schedutil governor since they are both using the same metric to calculate load. Note that, this (and CPU frequency scaling in general) doesn't work that well with idle injection as that is done from rt threads and is counted as load while it tries to do quite the opposite. That should be solved separately though. This was tested on ARM Hikey6220 platform with hackbench, sysbench and schbench. None of them showed any regression or significant improvements. Schbench is the most important ones out of these as it creates the scenario where the utilization numbers provide a better estimate of the future. Scenario 1: The CPUs were mostly idle in the previous polling window of the IPA governor as the tasks were sleeping and here are the details from traces (load is in %): Old: thermal_power_cpu_get_power: cpus=00000000,000000ff freq=1200000 total_load=203 load={{0x35,0x1,0x0,0x31,0x0,0x0,0x64,0x0}} dynamic_power=1339 New: thermal_power_cpu_get_power: cpus=00000000,000000ff freq=1200000 total_load=600 load={{0x60,0x46,0x45,0x45,0x48,0x3b,0x61,0x44}} dynamic_power=3960 Here, the "Old" line gives the load and requested_power (dynamic_power here) numbers calculated using the idle time based implementation, while "New" is based on the CPU utilization from scheduler. As can be clearly seen, the load and requested_power numbers are simply incorrect in the idle time based approach and the numbers collected from CPU's utilization are much closer to the reality. Scenario 2: The CPUs were busy in the previous polling window of the IPA governor: Old: thermal_power_cpu_get_power: cpus=00000000,000000ff freq=1200000 total_load=800 load={{0x64,0x64,0x64,0x64,0x64,0x64,0x64,0x64}} dynamic_power=5280 New: thermal_power_cpu_get_power: cpus=00000000,000000ff freq=1200000 total_load=708 load={{0x4d,0x5c,0x5c,0x5b,0x5c,0x5c,0x51,0x5b}} dynamic_power=4672 As can be seen, the idle time based load is 100% for all the CPUs as it took only the last window into account, but in reality the CPUs aren't that loaded as shown by the utilization numbers. Signed-off-by: Viresh Kumar --- drivers/thermal/cpufreq_cooling.c | 68 ++++++++++++++++++++++++------- 1 file changed, 54 insertions(+), 14 deletions(-) diff --git a/drivers/thermal/cpufreq_cooling.c b/drivers/thermal/cpufreq_cooling.c index cc2959f22f01..a364a2fd84b1 100644 --- a/drivers/thermal/cpufreq_cooling.c +++ b/drivers/thermal/cpufreq_cooling.c @@ -76,7 +76,9 @@ struct cpufreq_cooling_device { struct em_perf_domain *em; struct cpufreq_policy *policy; struct list_head node; +#ifndef CONFIG_SMP struct time_in_idle *idle_time; +#endif struct freq_qos_request qos_req; }; @@ -132,14 +134,35 @@ static u32 cpu_power_to_freq(struct cpufreq_cooling_device *cpufreq_cdev, } /** - * get_load() - get load for a cpu since last updated - * @cpufreq_cdev: &struct cpufreq_cooling_device for this cpu - * @cpu: cpu number - * @cpu_idx: index of the cpu in time_in_idle* + * get_load() - get load for a cpu + * @cpufreq_cdev: struct cpufreq_cooling_device for the cpu + * @cpu: cpu number + * @cpu_idx: index of the cpu in time_in_idle array * * Return: The average load of cpu @cpu in percentage since this * function was last called. */ +#ifdef CONFIG_SMP +static u32 get_load(struct cpufreq_cooling_device *cpufreq_cdev, int cpu, + int cpu_idx) +{ + unsigned long max = arch_scale_cpu_capacity(cpu); + unsigned long util; + + util = sched_cpu_util(cpu, ENERGY_UTIL, max); + return (util * 100) / max; +} + +static inline int allocate_idle_time(struct cpufreq_cooling_device *cpufreq_cdev) +{ + return 0; +} + +static inline void free_idle_time(struct cpufreq_cooling_device *cpufreq_cdev) +{ +} + +#else /* !CONFIG_SMP */ static u32 get_load(struct cpufreq_cooling_device *cpufreq_cdev, int cpu, int cpu_idx) { @@ -162,6 +185,26 @@ static u32 get_load(struct cpufreq_cooling_device *cpufreq_cdev, int cpu, return load; } +static int allocate_idle_time(struct cpufreq_cooling_device *cpufreq_cdev) +{ + unsigned int num_cpus = cpumask_weight(cpufreq_cdev->policy->related_cpus); + + cpufreq_cdev->idle_time = kcalloc(num_cpus, + sizeof(*cpufreq_cdev->idle_time), + GFP_KERNEL); + if (!cpufreq_cdev->idle_time) + return -ENOMEM; + + return 0; +} + +static void free_idle_time(struct cpufreq_cooling_device *cpufreq_cdev) +{ + kfree(cpufreq_cdev->idle_time); + cpufreq_cdev->idle_time = NULL; +} +#endif /* CONFIG_SMP */ + /** * get_dynamic_power() - calculate the dynamic power * @cpufreq_cdev: &cpufreq_cooling_device for this cdev @@ -487,7 +530,7 @@ __cpufreq_cooling_register(struct device_node *np, struct thermal_cooling_device *cdev; struct cpufreq_cooling_device *cpufreq_cdev; char dev_name[THERMAL_NAME_LENGTH]; - unsigned int i, num_cpus; + unsigned int i; struct device *dev; int ret; struct thermal_cooling_device_ops *cooling_ops; @@ -498,7 +541,6 @@ __cpufreq_cooling_register(struct device_node *np, return ERR_PTR(-ENODEV); } - if (IS_ERR_OR_NULL(policy)) { pr_err("%s: cpufreq policy isn't valid: %p\n", __func__, policy); return ERR_PTR(-EINVAL); @@ -516,12 +558,10 @@ __cpufreq_cooling_register(struct device_node *np, return ERR_PTR(-ENOMEM); cpufreq_cdev->policy = policy; - num_cpus = cpumask_weight(policy->related_cpus); - cpufreq_cdev->idle_time = kcalloc(num_cpus, - sizeof(*cpufreq_cdev->idle_time), - GFP_KERNEL); - if (!cpufreq_cdev->idle_time) { - cdev = ERR_PTR(-ENOMEM); + + ret = allocate_idle_time(cpufreq_cdev); + if (ret) { + cdev = ERR_PTR(ret); goto free_cdev; } @@ -581,7 +621,7 @@ __cpufreq_cooling_register(struct device_node *np, remove_ida: ida_simple_remove(&cpufreq_ida, cpufreq_cdev->id); free_idle_time: - kfree(cpufreq_cdev->idle_time); + free_idle_time(cpufreq_cdev); free_cdev: kfree(cpufreq_cdev); return cdev; @@ -674,7 +714,7 @@ void cpufreq_cooling_unregister(struct thermal_cooling_device *cdev) thermal_cooling_device_unregister(cdev); freq_qos_remove_request(&cpufreq_cdev->qos_req); ida_simple_remove(&cpufreq_ida, cpufreq_cdev->id); - kfree(cpufreq_cdev->idle_time); + free_idle_time(cpufreq_cdev); kfree(cpufreq_cdev); } EXPORT_SYMBOL_GPL(cpufreq_cooling_unregister); -- 2.25.0.rc1.19.g042ed3e048af