From patchwork Tue Aug 22 12:48:37 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jie Zhan X-Patchwork-Id: 13360600 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8495FEE4996 for ; Tue, 22 Aug 2023 12:51:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235257AbjHVMv3 (ORCPT ); Tue, 22 Aug 2023 08:51:29 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38904 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231901AbjHVMv3 (ORCPT ); Tue, 22 Aug 2023 08:51:29 -0400 Received: from szxga01-in.huawei.com (szxga01-in.huawei.com [45.249.212.187]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3523FCC6; Tue, 22 Aug 2023 05:51:27 -0700 (PDT) Received: from dggpeml500019.china.huawei.com (unknown [172.30.72.57]) by szxga01-in.huawei.com (SkyGuard) with ESMTP id 4RVTdn53VSztRwS; Tue, 22 Aug 2023 20:47:41 +0800 (CST) Received: from localhost.localdomain (10.67.165.2) by dggpeml500019.china.huawei.com (7.185.36.137) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.31; Tue, 22 Aug 2023 20:51:24 +0800 From: Jie Zhan To: , CC: , , , , , , , Subject: [PATCH v2] cpufreq: Support per-policy performance boost Date: Tue, 22 Aug 2023 20:48:37 +0800 Message-ID: <20230822124837.3016641-1-zhanjie9@hisilicon.com> X-Mailer: git-send-email 2.30.0 MIME-Version: 1.0 X-Originating-IP: [10.67.165.2] X-ClientProxiedBy: dggems702-chm.china.huawei.com (10.3.19.179) To dggpeml500019.china.huawei.com (7.185.36.137) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org The boost control currently applies to the whole system. However, users may prefer to boost a subset of cores in order to provide prioritized performance to workloads running on the boosted cores. Enable per-policy boost by adding a 'boost' sysfs interface under each policy path. This can be found at: /sys/devices/system/cpu/cpufreq/policy<*>/boost Same to the global boost switch, writing 1/0 to the per-policy 'boost' enables/disables boost on a cpufreq policy respectively. The user view of global and per-policy boost controls should be: 1. Enabling global boost initially enables boost on all policies, and per-policy boost can then be enabled or disabled individually, given that the platform does support so. 2. Disabling global boost makes the per-policy boost interface illegal. Signed-off-by: Jie Zhan Reviewed-by: Wei Xu Acked-by: Viresh Kumar --- A possible question could be: why not just limiting 'scaling_max_freq'? Well, the fundamental difference is that per-policy boost could be more user-friendly. When global boost is enabled, it is not straightforward to figure out the base frequency for setting 'scaling_max_freq' to a non-boost value. Also, this is supposed to take effect on the physical upper frequency limit, reflected through 'cpuinfo_max_freq'. v1->v2: - Rename the interface from 'local_boost' to 'boost'. - Illegalize writing 0 to per-policy even if global boost is off. - Show the per-policy 'boost' file only when ->set_boost() is available. v1: https://lore.kernel.org/linux-pm/20230724075827.4160512-1-zhanjie9@hisilicon.com/ drivers/cpufreq/cpufreq.c | 43 +++++++++++++++++++++++++++++++++++++++ include/linux/cpufreq.h | 3 +++ 2 files changed, 46 insertions(+) diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c index 50bbc969ffe5..81e21fa070e1 100644 --- a/drivers/cpufreq/cpufreq.c +++ b/drivers/cpufreq/cpufreq.c @@ -86,6 +86,7 @@ static void cpufreq_governor_limits(struct cpufreq_policy *policy); static int cpufreq_set_policy(struct cpufreq_policy *policy, struct cpufreq_governor *new_gov, unsigned int new_pol); +static bool cpufreq_boost_supported(void); /* * Two notifier lists: the "policy" list is involved in the @@ -621,6 +622,40 @@ static ssize_t store_boost(struct kobject *kobj, struct kobj_attribute *attr, } define_one_global_rw(boost); +static ssize_t show_local_boost(struct cpufreq_policy *policy, char *buf) +{ + return sysfs_emit(buf, "%d\n", policy->boost_enabled); +} + +static ssize_t store_local_boost(struct cpufreq_policy *policy, + const char *buf, size_t count) +{ + int ret, enable; + + ret = kstrtoint(buf, 10, &enable); + if (ret || enable < 0 || enable > 1) + return -EINVAL; + + if (!cpufreq_driver->boost_enabled) + return -EINVAL; + + if (policy->boost_enabled == enable) + return count; + + cpus_read_lock(); + ret = cpufreq_driver->set_boost(policy, enable); + cpus_read_unlock(); + + if (ret) + return ret; + + policy->boost_enabled = enable; + + return count; +} + +static struct freq_attr local_boost = __ATTR(boost, 0644, show_local_boost, store_local_boost); + static struct cpufreq_governor *find_governor(const char *str_governor) { struct cpufreq_governor *t; @@ -1055,6 +1090,12 @@ static int cpufreq_add_dev_interface(struct cpufreq_policy *policy) return ret; } + if (cpufreq_boost_supported()) { + ret = sysfs_create_file(&policy->kobj, &local_boost.attr); + if (ret) + return ret; + } + return 0; } @@ -2716,6 +2757,8 @@ int cpufreq_boost_trigger_state(int state) ret = cpufreq_driver->set_boost(policy, state); if (ret) goto err_reset_state; + + policy->boost_enabled = state; } cpus_read_unlock(); diff --git a/include/linux/cpufreq.h b/include/linux/cpufreq.h index 172ff51c1b2a..fa02f2fa88c4 100644 --- a/include/linux/cpufreq.h +++ b/include/linux/cpufreq.h @@ -140,6 +140,9 @@ struct cpufreq_policy { */ bool dvfs_possible_from_any_cpu; + /* Per policy boost enabled flag. */ + bool boost_enabled; + /* Cached frequency lookup from cpufreq_driver_resolve_freq. */ unsigned int cached_target_freq; unsigned int cached_resolved_idx;