From patchwork Mon Aug 24 21:02:48 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ionela Voinescu X-Patchwork-Id: 11734371 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 647E1739 for ; Mon, 24 Aug 2020 21:05:31 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 21CC32067C for ; Mon, 24 Aug 2020 21:05:31 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="Kv+jXdSW" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 21CC32067C Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:MIME-Version:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:References:In-Reply-To:Message-Id:Date:Subject:To: From:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=0GCCQMo7D9ZYalQxpGvG0379ffFRO4cHpe/CMNVcS2M=; b=Kv+jXdSWi9Zu3YPbCdD7i8gSl8 WFnd2rWdAEIt6e2x7aKXKeKhB2rV7zIgGyHh3+nLPjrRJ6pcB24C/BTdTv7Ysn6QxfcKuPil4Ncps LR6yChViyl22AswGpGC8o6T6rZeJw+drSD8e+92A7tqYUnMmN9KVsROBHV4GP4SNs0Y/tZIH9knSy W05lsWDKWaSvDnh98Fa/PgV9lM6etenWtP75kkxowA64Hj3gkDH54AZOOuav+L7UeVn1lNFAy7dsv g2+hiL3xDTzFI3N1yUvAAt5An40A7lE9840otBF0dcIrrP52szZvv4lsMS1Sphur6Sdi2z4tAgGZT lEFZkI2Q==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1kAJdF-0000Ax-OI; Mon, 24 Aug 2020 21:03:57 +0000 Received: from foss.arm.com ([217.140.110.172]) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1kAJdA-00009B-Hn for linux-arm-kernel@lists.infradead.org; Mon, 24 Aug 2020 21:03:53 +0000 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 52DBE1FB; Mon, 24 Aug 2020 14:03:51 -0700 (PDT) Received: from e108754-lin.cambridge.arm.com (e108754-lin.cambridge.arm.com [10.1.199.49]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id D4B1D3F71F; Mon, 24 Aug 2020 14:03:49 -0700 (PDT) From: Ionela Voinescu To: rjw@rjwysocki.net, viresh.kumar@linaro.org, dietmar.eggemann@arm.com, catalin.marinas@arm.com, sudeep.holla@arm.com, will@kernel.org, valentin.schneider@arm.com Subject: [PATCH v3 1/5] arch_topology: validate input frequencies to arch_set_freq_scale() Date: Mon, 24 Aug 2020 22:02:48 +0100 Message-Id: <20200824210252.27486-2-ionela.voinescu@arm.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20200824210252.27486-1-ionela.voinescu@arm.com> References: <20200824210252.27486-1-ionela.voinescu@arm.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200824_170352_682845_90ADCB97 X-CRM114-Status: GOOD ( 13.82 ) X-Spam-Score: -2.3 (--) X-Spam-Report: SpamAssassin version 3.4.4 on merlin.infradead.org summary: Content analysis details: (-2.3 points) pts rule name description ---- ---------------------- -------------------------------------------------- -2.3 RCVD_IN_DNSWL_MED RBL: Sender listed at https://www.dnswl.org/, medium trust [217.140.110.172 listed in list.dnswl.org] 0.0 SPF_HELO_NONE SPF: HELO does not publish an SPF Record -0.0 SPF_PASS SPF: sender matches SPF record X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: ionela.voinescu@arm.com, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-pm@vger.kernel.org MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org The current frequency passed to arch_set_freq_scale() could end up being 0, signaling an error in setting a new frequency. Also, if the maximum frequency in 0, this will result in a division by 0 error. Therefore, validate these input values before using them for the setting of the frequency scale factor. Signed-off-by: Ionela Voinescu Cc: Sudeep Holla Cc: Rafael J. Wysocki --- drivers/base/arch_topology.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/base/arch_topology.c b/drivers/base/arch_topology.c index 75f72d684294..1aca82fcceb8 100644 --- a/drivers/base/arch_topology.c +++ b/drivers/base/arch_topology.c @@ -33,6 +33,9 @@ void arch_set_freq_scale(struct cpumask *cpus, unsigned long cur_freq, unsigned long scale; int i; + if (!cur_freq || !max_freq) + return; + /* * If the use of counters for FIE is enabled, just return as we don't * want to update the scale factor with information from CPUFREQ. From patchwork Mon Aug 24 21:02:49 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ionela Voinescu X-Patchwork-Id: 11734375 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id C234614E5 for ; Mon, 24 Aug 2020 21:05:42 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 8AD3A2067C for ; Mon, 24 Aug 2020 21:05:42 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="Y5wGnTu8" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 8AD3A2067C Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:MIME-Version:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:References:In-Reply-To:Message-Id:Date:Subject:To: From:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=0oIDA5CUMNkkU8LBjGqIxcs+Dvao+Pt0bM5Q2A9xvHo=; b=Y5wGnTu8LLAlWZ3qH8jp4Dmkne X1B801SXgwipDXp/EgEpphAzUIISXSnnVWxx70PVbTRCJo1SwhkdOCLIURE0bO3fEBA2ebIOmNQy4 CltiVcnaSWfpFFnzws7hnVGo1PXYTp2oPAw8dgGyS9c8jkKtM4onH1ED6+5z1dkvl8tKsf8pmh0qo aWbln8+jfkr08Smgx404g3h9yH18NWb2bIEmHIicyXHmHXdIfswZtaahdjJCvcEj29HbhG5RT8ch+ lVrRgxohwAqcYpvHu202hMVM1PhpoBLoJXELXs1yut5zIUlC0/89x4h0vcP3/uQBMKkqpjLqh/KW8 JcCaGk+A==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1kAJdL-0000DC-D6; Mon, 24 Aug 2020 21:04:03 +0000 Received: from foss.arm.com ([217.140.110.172]) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1kAJdD-0000A7-Db for linux-arm-kernel@lists.infradead.org; Mon, 24 Aug 2020 21:03:56 +0000 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 B1A2C1FB; Mon, 24 Aug 2020 14:03:53 -0700 (PDT) Received: from e108754-lin.cambridge.arm.com (e108754-lin.cambridge.arm.com [10.1.199.49]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 478DE3F71F; Mon, 24 Aug 2020 14:03:52 -0700 (PDT) From: Ionela Voinescu To: rjw@rjwysocki.net, viresh.kumar@linaro.org, dietmar.eggemann@arm.com, catalin.marinas@arm.com, sudeep.holla@arm.com, will@kernel.org, valentin.schneider@arm.com Subject: [PATCH v3 2/5] cpufreq: move invariance setter calls in cpufreq core Date: Mon, 24 Aug 2020 22:02:49 +0100 Message-Id: <20200824210252.27486-3-ionela.voinescu@arm.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20200824210252.27486-1-ionela.voinescu@arm.com> References: <20200824210252.27486-1-ionela.voinescu@arm.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200824_170355_618571_52BE1C8C X-CRM114-Status: GOOD ( 25.53 ) X-Spam-Score: -2.3 (--) X-Spam-Report: SpamAssassin version 3.4.4 on merlin.infradead.org summary: Content analysis details: (-2.3 points) pts rule name description ---- ---------------------- -------------------------------------------------- -2.3 RCVD_IN_DNSWL_MED RBL: Sender listed at https://www.dnswl.org/, medium trust [217.140.110.172 listed in list.dnswl.org] 0.0 SPF_HELO_NONE SPF: HELO does not publish an SPF Record -0.0 SPF_PASS SPF: sender matches SPF record X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: ionela.voinescu@arm.com, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-pm@vger.kernel.org MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org To properly scale its per-entity load-tracking signals, the task scheduler needs to be given a frequency scale factor, i.e. some image of the current frequency the CPU is running at. Currently, this scale can be computed either by using counters (APERF/MPERF on x86, AMU on arm64), or by piggy-backing on the frequency selection done by cpufreq. For the latter, drivers have to explicitly set the scale factor themselves, despite it being purely boiler-plate code: the required information depends entirely on the kind of frequency switch callback implemented by the driver, i.e. either of: target_index(), target(), fast_switch() and setpolicy(). The fitness of those callbacks with regard to driving the Frequency Invariance Engine (FIE) is studied below: target_index() ============== Documentation states that the chosen frequency "must be determined by freq_table[index].frequency". It isn't clear if it *has* to be that frequency, or if it can use that frequency value to do some computation that ultimately leads to a different frequency selection. All drivers go for the former, while the vexpress-spc-cpufreq has an atypical implementation which is handled separately. Therefore, the hook works on the assumption the core can use freq_table[index].frequency. target() ======= This has been flagged as deprecated since: commit 9c0ebcf78fde ("cpufreq: Implement light weight ->target_index() routine") It also doesn't have that many users: gx-suspmod.c:439: .target = cpufreq_gx_target, s3c24xx-cpufreq.c:428: .target = s3c_cpufreq_target, intel_pstate.c:2528: .target = intel_cpufreq_target, cppc_cpufreq.c:401: .target = cppc_cpufreq_set_target, cpufreq-nforce2.c:371: .target = nforce2_target, sh-cpufreq.c:163: .target = sh_cpufreq_target, pcc-cpufreq.c:573: .target = pcc_cpufreq_target, Similarly to the path taken for target_index() calls in the cpufreq core during a frequency change, all of the drivers above will mark the end of a frequency change by a call to cpufreq_freq_transition_end(). Therefore, cpufreq_freq_transition_end() can be used as the location for the arch_set_freq_scale() call to potentially inform the scheduler of the frequency change. This change maintains the previous functionality for the drivers that implement the target_index() callback, while also adding support for the few drivers that implement the deprecated target() callback. fast_switch() ============= This callback *has* to return the frequency that was selected. setpolicy() =========== This callback does not have any designated way of informing what was the end choice. But there are only two drivers using setpolicy(), and none of them have current FIE support: drivers/cpufreq/longrun.c:281: .setpolicy = longrun_set_policy, drivers/cpufreq/intel_pstate.c:2215: .setpolicy = intel_pstate_set_policy, The intel_pstate is known to use counter-driven frequency invariance. Conclusion ========== Given that the significant majority of current FIE enabled drivers use callbacks that lend themselves to triggering the setting of the FIE scale factor in a generic way, move the invariance setter calls to cpufreq core. As a result of setting the frequency scale factor in cpufreq core, after callbacks that lend themselves to trigger it, remove this functionality from the driver side. To be noted that despite marking a successful frequency change, many cpufreq drivers will consider the new frequency as the requested frequency, although this is might not be the one granted by the hardware. Therefore, the call to arch_set_freq_scale() is a "best effort" one, and it is up to the architecture if the new frequency is used in the new frequency scale factor setting (determined by the implementation of arch_set_freq_scale()) or eventually used by the scheduler (determined by the implementation of arch_scale_freq_capacity()). The architecture is in a better position to decide if it has better methods to obtain more accurate information regarding the current frequency and use that information instead (for example, the use of counters). Also, the implementation to arch_set_freq_scale() will now have to handle error conditions (current frequency == 0) in order to prevent the overhead in cpufreq core when the default arch_set_freq_scale() implementation is used. Signed-off-by: Ionela Voinescu Suggested-by: Valentin Schneider Cc: Rafael J. Wysocki Cc: Viresh Kumar Acked-by: Viresh Kumar --- drivers/cpufreq/cpufreq-dt.c | 10 +--------- drivers/cpufreq/cpufreq.c | 12 +++++++++++- drivers/cpufreq/qcom-cpufreq-hw.c | 9 +-------- drivers/cpufreq/scmi-cpufreq.c | 12 ++---------- drivers/cpufreq/scpi-cpufreq.c | 6 +----- drivers/cpufreq/vexpress-spc-cpufreq.c | 12 ++---------- 6 files changed, 18 insertions(+), 43 deletions(-) diff --git a/drivers/cpufreq/cpufreq-dt.c b/drivers/cpufreq/cpufreq-dt.c index 944d7b45afe9..9fd4ce774f12 100644 --- a/drivers/cpufreq/cpufreq-dt.c +++ b/drivers/cpufreq/cpufreq-dt.c @@ -40,16 +40,8 @@ static int set_target(struct cpufreq_policy *policy, unsigned int index) { struct private_data *priv = policy->driver_data; unsigned long freq = policy->freq_table[index].frequency; - int ret; - - ret = dev_pm_opp_set_rate(priv->cpu_dev, freq * 1000); - if (!ret) { - arch_set_freq_scale(policy->related_cpus, freq, - policy->cpuinfo.max_freq); - } - - return ret; + return dev_pm_opp_set_rate(priv->cpu_dev, freq * 1000); } /* diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c index 02ab56b2a0d8..34533c6b3bd0 100644 --- a/drivers/cpufreq/cpufreq.c +++ b/drivers/cpufreq/cpufreq.c @@ -446,6 +446,10 @@ void cpufreq_freq_transition_end(struct cpufreq_policy *policy, cpufreq_notify_post_transition(policy, freqs, transition_failed); + arch_set_freq_scale(policy->related_cpus, + policy->cur, + policy->cpuinfo.max_freq); + policy->transition_ongoing = false; policy->transition_task = NULL; @@ -2057,9 +2061,15 @@ EXPORT_SYMBOL(cpufreq_unregister_notifier); unsigned int cpufreq_driver_fast_switch(struct cpufreq_policy *policy, unsigned int target_freq) { + unsigned int freq; + target_freq = clamp_val(target_freq, policy->min, policy->max); + freq = cpufreq_driver->fast_switch(policy, target_freq); + + arch_set_freq_scale(policy->related_cpus, freq, + policy->cpuinfo.max_freq); - return cpufreq_driver->fast_switch(policy, target_freq); + return freq; } EXPORT_SYMBOL_GPL(cpufreq_driver_fast_switch); diff --git a/drivers/cpufreq/qcom-cpufreq-hw.c b/drivers/cpufreq/qcom-cpufreq-hw.c index 3fb044b907a8..aabe4306d92f 100644 --- a/drivers/cpufreq/qcom-cpufreq-hw.c +++ b/drivers/cpufreq/qcom-cpufreq-hw.c @@ -85,8 +85,6 @@ static int qcom_cpufreq_hw_target_index(struct cpufreq_policy *policy, if (icc_scaling_enabled) qcom_cpufreq_set_bw(policy, freq); - arch_set_freq_scale(policy->related_cpus, freq, - policy->cpuinfo.max_freq); return 0; } @@ -113,16 +111,11 @@ static unsigned int qcom_cpufreq_hw_fast_switch(struct cpufreq_policy *policy, { void __iomem *perf_state_reg = policy->driver_data; unsigned int index; - unsigned long freq; index = policy->cached_resolved_idx; writel_relaxed(index, perf_state_reg); - freq = policy->freq_table[index].frequency; - arch_set_freq_scale(policy->related_cpus, freq, - policy->cpuinfo.max_freq); - - return freq; + return policy->freq_table[index].frequency; } static int qcom_cpufreq_hw_read_lut(struct device *cpu_dev, diff --git a/drivers/cpufreq/scmi-cpufreq.c b/drivers/cpufreq/scmi-cpufreq.c index fb42e3390377..6dd1311660b5 100644 --- a/drivers/cpufreq/scmi-cpufreq.c +++ b/drivers/cpufreq/scmi-cpufreq.c @@ -48,16 +48,11 @@ static unsigned int scmi_cpufreq_get_rate(unsigned int cpu) static int scmi_cpufreq_set_target(struct cpufreq_policy *policy, unsigned int index) { - int ret; struct scmi_data *priv = policy->driver_data; struct scmi_perf_ops *perf_ops = handle->perf_ops; u64 freq = policy->freq_table[index].frequency; - ret = perf_ops->freq_set(handle, priv->domain_id, freq * 1000, false); - if (!ret) - arch_set_freq_scale(policy->related_cpus, freq, - policy->cpuinfo.max_freq); - return ret; + return perf_ops->freq_set(handle, priv->domain_id, freq * 1000, false); } static unsigned int scmi_cpufreq_fast_switch(struct cpufreq_policy *policy, @@ -67,11 +62,8 @@ static unsigned int scmi_cpufreq_fast_switch(struct cpufreq_policy *policy, struct scmi_perf_ops *perf_ops = handle->perf_ops; if (!perf_ops->freq_set(handle, priv->domain_id, - target_freq * 1000, true)) { - arch_set_freq_scale(policy->related_cpus, target_freq, - policy->cpuinfo.max_freq); + target_freq * 1000, true)) return target_freq; - } return 0; } diff --git a/drivers/cpufreq/scpi-cpufreq.c b/drivers/cpufreq/scpi-cpufreq.c index b0f5388b8854..43db05b949d9 100644 --- a/drivers/cpufreq/scpi-cpufreq.c +++ b/drivers/cpufreq/scpi-cpufreq.c @@ -47,9 +47,8 @@ static unsigned int scpi_cpufreq_get_rate(unsigned int cpu) static int scpi_cpufreq_set_target(struct cpufreq_policy *policy, unsigned int index) { - unsigned long freq = policy->freq_table[index].frequency; + u64 rate = policy->freq_table[index].frequency * 1000; struct scpi_data *priv = policy->driver_data; - u64 rate = freq * 1000; int ret; ret = clk_set_rate(priv->clk, rate); @@ -60,9 +59,6 @@ scpi_cpufreq_set_target(struct cpufreq_policy *policy, unsigned int index) if (clk_get_rate(priv->clk) != rate) return -EIO; - arch_set_freq_scale(policy->related_cpus, freq, - policy->cpuinfo.max_freq); - return 0; } diff --git a/drivers/cpufreq/vexpress-spc-cpufreq.c b/drivers/cpufreq/vexpress-spc-cpufreq.c index 4e8b1dee7c9a..e89b905754d2 100644 --- a/drivers/cpufreq/vexpress-spc-cpufreq.c +++ b/drivers/cpufreq/vexpress-spc-cpufreq.c @@ -182,7 +182,6 @@ static int ve_spc_cpufreq_set_target(struct cpufreq_policy *policy, { u32 cpu = policy->cpu, cur_cluster, new_cluster, actual_cluster; unsigned int freqs_new; - int ret; cur_cluster = cpu_to_cluster(cpu); new_cluster = actual_cluster = per_cpu(physical_cluster, cpu); @@ -197,15 +196,8 @@ static int ve_spc_cpufreq_set_target(struct cpufreq_policy *policy, new_cluster = A15_CLUSTER; } - ret = ve_spc_cpufreq_set_rate(cpu, actual_cluster, new_cluster, - freqs_new); - - if (!ret) { - arch_set_freq_scale(policy->related_cpus, freqs_new, - policy->cpuinfo.max_freq); - } - - return ret; + return ve_spc_cpufreq_set_rate(cpu, actual_cluster, new_cluster, + freqs_new); } static inline u32 get_table_count(struct cpufreq_frequency_table *table) From patchwork Mon Aug 24 21:02:50 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ionela Voinescu X-Patchwork-Id: 11734369 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 33C4F13B1 for ; Mon, 24 Aug 2020 21:04:28 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 09CA220866 for ; 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Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1kAJdU-0000GN-8a; Mon, 24 Aug 2020 21:04:12 +0000 Received: from foss.arm.com ([217.140.110.172]) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1kAJdE-0000Ay-Lf for linux-arm-kernel@lists.infradead.org; Mon, 24 Aug 2020 21:03:58 +0000 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 09C1331B; Mon, 24 Aug 2020 14:03:56 -0700 (PDT) Received: from e108754-lin.cambridge.arm.com (e108754-lin.cambridge.arm.com [10.1.199.49]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 9445E3F71F; Mon, 24 Aug 2020 14:03:54 -0700 (PDT) From: Ionela Voinescu To: rjw@rjwysocki.net, viresh.kumar@linaro.org, dietmar.eggemann@arm.com, catalin.marinas@arm.com, sudeep.holla@arm.com, will@kernel.org, valentin.schneider@arm.com Subject: [PATCH v3 3/5] cpufreq: report whether cpufreq supports Frequency Invariance (FI) Date: Mon, 24 Aug 2020 22:02:50 +0100 Message-Id: <20200824210252.27486-4-ionela.voinescu@arm.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20200824210252.27486-1-ionela.voinescu@arm.com> References: <20200824210252.27486-1-ionela.voinescu@arm.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200824_170356_890255_4BF9316A X-CRM114-Status: GOOD ( 15.96 ) X-Spam-Score: -2.3 (--) X-Spam-Report: SpamAssassin version 3.4.4 on merlin.infradead.org summary: Content analysis details: (-2.3 points) pts rule name description ---- ---------------------- -------------------------------------------------- -2.3 RCVD_IN_DNSWL_MED RBL: Sender listed at https://www.dnswl.org/, medium trust [217.140.110.172 listed in list.dnswl.org] 0.0 SPF_HELO_NONE SPF: HELO does not publish an SPF Record -0.0 SPF_PASS SPF: sender matches SPF record X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: ionela.voinescu@arm.com, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-pm@vger.kernel.org MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org Now that the update of the FI scale factor is done in cpufreq core for selected functions - target(), target_index() and fast_switch(), we can provide feedback to the task scheduler and architecture code on whether cpufreq supports FI. For this purpose provide an external function to expose whether the cpufreq drivers support FI, by using a static key. The logic behind the enablement of cpufreq-based invariance is as follows: - cpufreq-based invariance is disabled by default - cpufreq-based invariance is enabled if any of the callbacks above is implemented while the unsupported setpolicy() is not The cpufreq_supports_freq_invariance() function only returns whether cpufreq is instrumented with the arch_set_freq_scale() calls that result in support for frequency invariance. Due to the lack of knowledge on whether the implementation of arch_set_freq_scale() actually results in the setting of a scale factor based on cpufreq information, it is up to the architecture code to ensure the setting and provision of the scale factor to the scheduler. Signed-off-by: Ionela Voinescu Cc: Rafael J. Wysocki Cc: Viresh Kumar --- drivers/cpufreq/cpufreq.c | 20 ++++++++++++++++++++ include/linux/cpufreq.h | 5 +++++ 2 files changed, 25 insertions(+) diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c index 34533c6b3bd0..b3a7d1cc5e92 100644 --- a/drivers/cpufreq/cpufreq.c +++ b/drivers/cpufreq/cpufreq.c @@ -61,6 +61,9 @@ static struct cpufreq_driver *cpufreq_driver; static DEFINE_PER_CPU(struct cpufreq_policy *, cpufreq_cpu_data); static DEFINE_RWLOCK(cpufreq_driver_lock); +/* Mark support for the scheduler's frequency invariance engine */ +static DEFINE_STATIC_KEY_FALSE(cpufreq_freq_invariance); + /* Flag to suspend/resume CPUFreq governors */ static bool cpufreq_suspended; @@ -69,6 +72,20 @@ static inline bool has_target(void) return cpufreq_driver->target_index || cpufreq_driver->target; } +static inline +void enable_cpufreq_freq_invariance(struct cpufreq_driver *driver) +{ + if (!driver->setpolicy) { + static_branch_enable_cpuslocked(&cpufreq_freq_invariance); + pr_debug("supports frequency invariance"); + } +} + +bool cpufreq_supports_freq_invariance(void) +{ + return static_branch_likely(&cpufreq_freq_invariance); +} + /* internal prototypes */ static unsigned int __cpufreq_get(struct cpufreq_policy *policy); static int cpufreq_init_governor(struct cpufreq_policy *policy); @@ -2721,6 +2738,8 @@ int cpufreq_register_driver(struct cpufreq_driver *driver_data) cpufreq_driver = driver_data; write_unlock_irqrestore(&cpufreq_driver_lock, flags); + enable_cpufreq_freq_invariance(cpufreq_driver); + if (driver_data->setpolicy) driver_data->flags |= CPUFREQ_CONST_LOOPS; @@ -2790,6 +2809,7 @@ int cpufreq_unregister_driver(struct cpufreq_driver *driver) cpus_read_lock(); subsys_interface_unregister(&cpufreq_interface); remove_boost_sysfs_file(); + static_branch_disable_cpuslocked(&cpufreq_freq_invariance); cpuhp_remove_state_nocalls_cpuslocked(hp_online); write_lock_irqsave(&cpufreq_driver_lock, flags); diff --git a/include/linux/cpufreq.h b/include/linux/cpufreq.h index 8f141d4c859c..091df9968945 100644 --- a/include/linux/cpufreq.h +++ b/include/linux/cpufreq.h @@ -217,6 +217,7 @@ void refresh_frequency_limits(struct cpufreq_policy *policy); void cpufreq_update_policy(unsigned int cpu); void cpufreq_update_limits(unsigned int cpu); bool have_governor_per_policy(void); +bool cpufreq_supports_freq_invariance(void); struct kobject *get_governor_parent_kobj(struct cpufreq_policy *policy); void cpufreq_enable_fast_switch(struct cpufreq_policy *policy); void cpufreq_disable_fast_switch(struct cpufreq_policy *policy); @@ -237,6 +238,10 @@ static inline unsigned int cpufreq_get_hw_max_freq(unsigned int cpu) { return 0; } +static inline bool cpufreq_supports_freq_invariance(void) +{ + return false; +} static inline void disable_cpufreq(void) { } #endif From patchwork Mon Aug 24 21:02:51 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ionela Voinescu X-Patchwork-Id: 11734377 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 895481731 for ; Mon, 24 Aug 2020 21:05:44 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 63C102067C for ; 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Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1kAJda-0000MP-Gg; Mon, 24 Aug 2020 21:04:18 +0000 Received: from foss.arm.com ([217.140.110.172]) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1kAJdH-0000Bx-Dy for linux-arm-kernel@lists.infradead.org; Mon, 24 Aug 2020 21:04:00 +0000 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 41699D6E; Mon, 24 Aug 2020 14:03:58 -0700 (PDT) Received: from e108754-lin.cambridge.arm.com (e108754-lin.cambridge.arm.com [10.1.199.49]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id CBAC03F71F; Mon, 24 Aug 2020 14:03:56 -0700 (PDT) From: Ionela Voinescu To: rjw@rjwysocki.net, viresh.kumar@linaro.org, dietmar.eggemann@arm.com, catalin.marinas@arm.com, sudeep.holla@arm.com, will@kernel.org, valentin.schneider@arm.com Subject: [PATCH v3 4/5] arch_topology, cpufreq: constify arch_* cpumasks Date: Mon, 24 Aug 2020 22:02:51 +0100 Message-Id: <20200824210252.27486-5-ionela.voinescu@arm.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20200824210252.27486-1-ionela.voinescu@arm.com> References: <20200824210252.27486-1-ionela.voinescu@arm.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200824_170359_659077_CEBE73E7 X-CRM114-Status: GOOD ( 14.02 ) X-Spam-Score: -2.3 (--) X-Spam-Report: SpamAssassin version 3.4.4 on merlin.infradead.org summary: Content analysis details: (-2.3 points) pts rule name description ---- ---------------------- -------------------------------------------------- -2.3 RCVD_IN_DNSWL_MED RBL: Sender listed at https://www.dnswl.org/, medium trust [217.140.110.172 listed in list.dnswl.org] 0.0 SPF_HELO_NONE SPF: HELO does not publish an SPF Record -0.0 SPF_PASS SPF: sender matches SPF record X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: ionela.voinescu@arm.com, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-pm@vger.kernel.org MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org From: Valentin Schneider The passed cpumask arguments to arch_set_freq_scale() and arch_freq_counters_available() are only iterated over, so reflect this in the prototype. This also allows to pass system cpumasks like cpu_online_mask without getting a warning. Signed-off-by: Valentin Schneider Signed-off-by: Ionela Voinescu Acked-by: Catalin Marinas Cc: Catalin Marinas Cc: Will Deacon Cc: Sudeep Holla Cc: Rafael J. Wysocki Cc: Viresh Kumar Acked-by: Viresh Kumar --- arch/arm64/kernel/topology.c | 2 +- drivers/base/arch_topology.c | 4 ++-- drivers/cpufreq/cpufreq.c | 5 +++-- include/linux/arch_topology.h | 2 +- include/linux/cpufreq.h | 3 ++- 5 files changed, 9 insertions(+), 7 deletions(-) diff --git a/arch/arm64/kernel/topology.c b/arch/arm64/kernel/topology.c index 0801a0f3c156..9a9f2b8dedf5 100644 --- a/arch/arm64/kernel/topology.c +++ b/arch/arm64/kernel/topology.c @@ -253,7 +253,7 @@ static int __init init_amu_fie(void) } late_initcall_sync(init_amu_fie); -bool arch_freq_counters_available(struct cpumask *cpus) +bool arch_freq_counters_available(const struct cpumask *cpus) { return amu_freq_invariant() && cpumask_subset(cpus, amu_fie_cpus); diff --git a/drivers/base/arch_topology.c b/drivers/base/arch_topology.c index 1aca82fcceb8..43d40822b956 100644 --- a/drivers/base/arch_topology.c +++ b/drivers/base/arch_topology.c @@ -21,13 +21,13 @@ #include #include -__weak bool arch_freq_counters_available(struct cpumask *cpus) +__weak bool arch_freq_counters_available(const struct cpumask *cpus) { return false; } DEFINE_PER_CPU(unsigned long, freq_scale) = SCHED_CAPACITY_SCALE; -void arch_set_freq_scale(struct cpumask *cpus, unsigned long cur_freq, +void arch_set_freq_scale(const struct cpumask *cpus, unsigned long cur_freq, unsigned long max_freq) { unsigned long scale; diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c index b3a7d1cc5e92..ae41eb011557 100644 --- a/drivers/cpufreq/cpufreq.c +++ b/drivers/cpufreq/cpufreq.c @@ -171,8 +171,9 @@ u64 get_cpu_idle_time(unsigned int cpu, u64 *wall, int io_busy) } EXPORT_SYMBOL_GPL(get_cpu_idle_time); -__weak void arch_set_freq_scale(struct cpumask *cpus, unsigned long cur_freq, - unsigned long max_freq) +__weak void arch_set_freq_scale(const struct cpumask *cpus, + unsigned long cur_freq, + unsigned long max_freq) { } EXPORT_SYMBOL_GPL(arch_set_freq_scale); diff --git a/include/linux/arch_topology.h b/include/linux/arch_topology.h index 69b1dabe39dc..810c83336257 100644 --- a/include/linux/arch_topology.h +++ b/include/linux/arch_topology.h @@ -30,7 +30,7 @@ static inline unsigned long topology_get_freq_scale(int cpu) return per_cpu(freq_scale, cpu); } -bool arch_freq_counters_available(struct cpumask *cpus); +bool arch_freq_counters_available(const struct cpumask *cpus); DECLARE_PER_CPU(unsigned long, thermal_pressure); diff --git a/include/linux/cpufreq.h b/include/linux/cpufreq.h index 091df9968945..8f22072c8d90 100644 --- a/include/linux/cpufreq.h +++ b/include/linux/cpufreq.h @@ -1011,7 +1011,8 @@ static inline void sched_cpufreq_governor_change(struct cpufreq_policy *policy, extern void arch_freq_prepare_all(void); extern unsigned int arch_freq_get_on_cpu(int cpu); -extern void arch_set_freq_scale(struct cpumask *cpus, unsigned long cur_freq, +extern void arch_set_freq_scale(const struct cpumask *cpus, + unsigned long cur_freq, unsigned long max_freq); /* the following are really really optional */ From patchwork Mon Aug 24 21:02:52 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ionela Voinescu X-Patchwork-Id: 11734379 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id E3E291731 for ; 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Mon, 24 Aug 2020 14:03:58 -0700 (PDT) From: Ionela Voinescu To: rjw@rjwysocki.net, viresh.kumar@linaro.org, dietmar.eggemann@arm.com, catalin.marinas@arm.com, sudeep.holla@arm.com, will@kernel.org, valentin.schneider@arm.com Subject: [PATCH v3 5/5] arch_topology, arm, arm64: define arch_scale_freq_invariant() Date: Mon, 24 Aug 2020 22:02:52 +0100 Message-Id: <20200824210252.27486-6-ionela.voinescu@arm.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20200824210252.27486-1-ionela.voinescu@arm.com> References: <20200824210252.27486-1-ionela.voinescu@arm.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200824_170406_382481_FB3C135D X-CRM114-Status: GOOD ( 19.45 ) X-Spam-Score: -2.3 (--) X-Spam-Report: SpamAssassin version 3.4.4 on merlin.infradead.org summary: Content analysis details: (-2.3 points) pts rule name description ---- ---------------------- -------------------------------------------------- -2.3 RCVD_IN_DNSWL_MED RBL: Sender listed at https://www.dnswl.org/, medium trust [217.140.110.172 listed in list.dnswl.org] 0.0 SPF_HELO_NONE SPF: HELO does not publish an SPF Record -0.0 SPF_PASS SPF: sender matches SPF record X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: ionela.voinescu@arm.com, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-pm@vger.kernel.org MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org From: Valentin Schneider arch_scale_freq_invariant() is used by schedutil to determine whether the scheduler's load-tracking signals are frequency invariant. Its definition is overridable, though by default it is hardcoded to 'true' if arch_scale_freq_capacity() is defined ('false' otherwise). This behaviour is not overridden on arm, arm64 and other users of the generic arch topology driver, which is somewhat precarious: arch_scale_freq_capacity() will always be defined, yet not all cpufreq drivers are guaranteed to drive the frequency invariance scale factor setting. In other words, the load-tracking signals may very well *not* be frequency invariant. Now that cpufreq can be queried on whether the current driver is driving the Frequency Invariance (FI) scale setting, the current situation can be improved. This combines the query of whether cpufreq supports the setting of the frequency scale factor, with whether all online CPUs are counter-based FI enabled. While cpufreq FI enablement applies at system level, for all CPUs, counter-based FI support could also be used for only a subset of CPUs to set the invariance scale factor. Therefore, if cpufreq-based FI support is present, we consider the system to be invariant. If missing, we require all online CPUs to be counter-based FI enabled in order for the full system to be considered invariant. If the system ends up not being invariant, a new condition is needed in the counter initialization code that disables all scale factor setting based on counters. Precedence of counters over cpufreq use is not important here. The invariant status is only given to the system if all CPUs have at least one method of setting the frequency scale factor. Signed-off-by: Valentin Schneider Signed-off-by: Ionela Voinescu Acked-by: Catalin Marinas Cc: Catalin Marinas Cc: Will Deacon Cc: Sudeep Holla Acked-by: Viresh Kumar --- arch/arm/include/asm/topology.h | 1 + arch/arm64/include/asm/topology.h | 1 + arch/arm64/kernel/topology.c | 7 +++++++ drivers/base/arch_topology.c | 6 ++++++ include/linux/arch_topology.h | 2 ++ 5 files changed, 17 insertions(+) diff --git a/arch/arm/include/asm/topology.h b/arch/arm/include/asm/topology.h index e0593cf095d0..9219e67befbe 100644 --- a/arch/arm/include/asm/topology.h +++ b/arch/arm/include/asm/topology.h @@ -9,6 +9,7 @@ /* Replace task scheduler's default frequency-invariant accounting */ #define arch_scale_freq_capacity topology_get_freq_scale +#define arch_scale_freq_invariant topology_scale_freq_invariant /* Replace task scheduler's default cpu-invariant accounting */ #define arch_scale_cpu_capacity topology_get_cpu_scale diff --git a/arch/arm64/include/asm/topology.h b/arch/arm64/include/asm/topology.h index e042f6527981..7cb519473fbd 100644 --- a/arch/arm64/include/asm/topology.h +++ b/arch/arm64/include/asm/topology.h @@ -27,6 +27,7 @@ void topology_scale_freq_tick(void); /* Replace task scheduler's default frequency-invariant accounting */ #define arch_scale_freq_capacity topology_get_freq_scale +#define arch_scale_freq_invariant topology_scale_freq_invariant /* Replace task scheduler's default cpu-invariant accounting */ #define arch_scale_cpu_capacity topology_get_cpu_scale diff --git a/arch/arm64/kernel/topology.c b/arch/arm64/kernel/topology.c index 9a9f2b8dedf5..4064d39bb66d 100644 --- a/arch/arm64/kernel/topology.c +++ b/arch/arm64/kernel/topology.c @@ -246,6 +246,13 @@ static int __init init_amu_fie(void) static_branch_enable(&amu_fie_key); } + /* + * If the system is not fully invariant after AMU init, disable + * partial use of counters for frequency invariance. + */ + if (!topology_scale_freq_invariant()) + static_branch_disable(&amu_fie_key); + free_valid_mask: free_cpumask_var(valid_cpus); diff --git a/drivers/base/arch_topology.c b/drivers/base/arch_topology.c index 43d40822b956..3b24c31f0444 100644 --- a/drivers/base/arch_topology.c +++ b/drivers/base/arch_topology.c @@ -21,6 +21,12 @@ #include #include +bool topology_scale_freq_invariant(void) +{ + return cpufreq_supports_freq_invariance() || + arch_freq_counters_available(cpu_online_mask); +} + __weak bool arch_freq_counters_available(const struct cpumask *cpus) { return false; diff --git a/include/linux/arch_topology.h b/include/linux/arch_topology.h index 810c83336257..083df331a3c9 100644 --- a/include/linux/arch_topology.h +++ b/include/linux/arch_topology.h @@ -30,6 +30,8 @@ static inline unsigned long topology_get_freq_scale(int cpu) return per_cpu(freq_scale, cpu); } +bool topology_scale_freq_invariant(void); + bool arch_freq_counters_available(const struct cpumask *cpus); DECLARE_PER_CPU(unsigned long, thermal_pressure);