From patchwork Mon Jun 3 08:13:31 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Beata Michalska X-Patchwork-Id: 13683374 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id F2C8D59B4A; Mon, 3 Jun 2024 08:13:53 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1717402436; cv=none; b=td64iQUSC3WsLSyD1+I0+qw8TIzOXpre68BEnsGvDXc7vGFTzym4EavgTi6mivsHDs6QSCuizdY7AfJQ+Dw2Mkh1Bnt4Gl6/+9oWkx0N3HQN7JSBEDRfLbQ4EjfoZ/ILjwh2nVsa1pCftiD1308APHmmw+62RR7Z4hBEdxZZ2eE= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1717402436; c=relaxed/simple; bh=yhcFTKDrrJswRkQGSVNrK7EEevy1VSzs20U97xZ+xfQ=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=l/XsAiyBiLS7QwBNM8f7Hkapk9wkHk7tpnfqKWEb1jxO3+m/PXEfbUkKUA4A0lrqLiPX72zbwpb2PdxGV8ABD2V+PFevAdYuYbBqv5axLYO9gj2ssTDVCtItgrNqgacI5ztmTvDGpx0Bpx3FZ8DhglwO2IYKRoKdJbsioMfbMVE= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 7EE381063; Mon, 3 Jun 2024 01:14:17 -0700 (PDT) Received: from e125905.cambridge.arm.com (e125905.cambridge.arm.com [10.1.194.73]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 150D33F792; Mon, 3 Jun 2024 01:13:51 -0700 (PDT) From: Beata Michalska To: linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org, rafael@kernel.org, viresh.kumar@linaro.org, len.brown@intel.com Cc: ionela.voinescu@arm.com, vanshikonda@os.amperecomputing.com, sumitg@nvidia.com Subject: [PATCH 1/1] cpufreq: Rewire arch specific feedback for cpuinfo/scaling_cur_freq Date: Mon, 3 Jun 2024 09:13:31 +0100 Message-Id: <20240603081331.3829278-2-beata.michalska@arm.com> In-Reply-To: <20240603081331.3829278-1-beata.michalska@arm.com> References: <20240603081331.3829278-1-beata.michalska@arm.com> Precedence: bulk X-Mailing-List: linux-pm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Some architectures provide a way to determine an average frequency over a certain period of time, based on available performance monitors (AMU on ARM or APERF/MPERf on x86). With those at hand, enroll arch_freq_get_on_cpu into cpuinfo_cur_freq policy sysfs attribute handler, which is expected to represent the current frequency of a given CPU,as obtained by the hardware. This is the type of feedback that counters do provide. At the same time, keep the scaling_cur_freq attribute align with the docs and make it provide most recently requested frequency, still allowing to fallback to using arch_freq_get_on_cpu for cases when cpuinfo_cur_freq is not available. Signed-off-by: Beata Michalska --- drivers/cpufreq/cpufreq.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c index a45aac17c20f..3b0eabe4a983 100644 --- a/drivers/cpufreq/cpufreq.c +++ b/drivers/cpufreq/cpufreq.c @@ -758,7 +758,8 @@ static ssize_t show_scaling_cur_freq(struct cpufreq_policy *policy, char *buf) ssize_t ret; unsigned int freq; - freq = arch_freq_get_on_cpu(policy->cpu); + freq = !cpufreq_driver->get ? arch_freq_get_on_cpu(policy->cpu) + : 0; if (freq) ret = sprintf(buf, "%u\n", freq); else if (cpufreq_driver->setpolicy && cpufreq_driver->get) @@ -795,7 +796,10 @@ store_one(scaling_max_freq, max); static ssize_t show_cpuinfo_cur_freq(struct cpufreq_policy *policy, char *buf) { - unsigned int cur_freq = __cpufreq_get(policy); + unsigned int cur_freq = arch_freq_get_on_cpu(policy->cpu); + + if (!cur_freq) + cur_freq = __cpufreq_get(policy); if (cur_freq) return sprintf(buf, "%u\n", cur_freq);