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 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id B4D18C02182 for ; Tue, 21 Jan 2025 11:00:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: Content-Type:In-Reply-To:From:References:Cc:To:Subject:MIME-Version:Date: Message-ID:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=0p9kCPX0kFOEZOIBaQgiLe2sNq8cghl604dX/e+fCK8=; b=sR++xGNJpzCnN8kGsZqnHlPHYi 9/tQ4OL0edC5h3GVr63Xle6lWikUc8ecObFNODQMF6R3lrT/4sHraQXThVjhgzJ2HhXpKw6lFJD6X ns/DUrJBVL4NcPSrAiTtiqYWH8X4Q5QX4jMxKpycxxOpYiZnHzoxA3cS0UvHTnG6F/lfkThL4WbOx feQ82A1gRFF9PU/kzAHNs7RVZJBxV3VghAfxwdBq+2DwjlosUT5AEMr0XujsmiDpaCHwixedFbrWj wgfXP5ICQHtmmivry9VyIxzV5ulHFgQO6uWTDZwXGzSWqdUq2aQZlivZMvpzP1dh5J4LcWyYXh5Zy GLYOdWtw==; 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charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250121_024734_505414_57DA38DA X-CRM114-Status: GOOD ( 17.97 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On 21-01-2025 14:14, Beata Michalska wrote: > Allow arch_freq_get_on_cpu to return an error for cases when retrieving > current CPU frequency is not possible, whether that being due to lack of > required arch support or due to other circumstances when the current > frequency cannot be determined at given point of time. > > Signed-off-by: Beata Michalska > --- > arch/x86/kernel/cpu/aperfmperf.c | 2 +- > arch/x86/kernel/cpu/proc.c | 7 +++++-- > drivers/cpufreq/cpufreq.c | 8 ++++---- > include/linux/cpufreq.h | 2 +- > 4 files changed, 11 insertions(+), 8 deletions(-) > > diff --git a/arch/x86/kernel/cpu/aperfmperf.c b/arch/x86/kernel/cpu/aperfmperf.c > index f642de2ebdac..6cf31a1649c4 100644 > --- a/arch/x86/kernel/cpu/aperfmperf.c > +++ b/arch/x86/kernel/cpu/aperfmperf.c > @@ -498,7 +498,7 @@ void arch_scale_freq_tick(void) > */ > #define MAX_SAMPLE_AGE ((unsigned long)HZ / 50) > > -unsigned int arch_freq_get_on_cpu(int cpu) > +int arch_freq_get_on_cpu(int cpu) > { > struct aperfmperf *s = per_cpu_ptr(&cpu_samples, cpu); > unsigned int seq, freq; > diff --git a/arch/x86/kernel/cpu/proc.c b/arch/x86/kernel/cpu/proc.c > index 41ed01f46bd9..d79f5845a463 100644 > --- a/arch/x86/kernel/cpu/proc.c > +++ b/arch/x86/kernel/cpu/proc.c > @@ -86,9 +86,12 @@ static int show_cpuinfo(struct seq_file *m, void *v) > seq_printf(m, "microcode\t: 0x%x\n", c->microcode); > > if (cpu_has(c, X86_FEATURE_TSC)) { > - unsigned int freq = arch_freq_get_on_cpu(cpu); > + int freq = arch_freq_get_on_cpu(cpu); > > - seq_printf(m, "cpu MHz\t\t: %u.%03u\n", freq / 1000, (freq % 1000)); > + if (freq <= 0) > + seq_puts(m, "cpu MHz\t\t: Unknown\n"); > + else > + seq_printf(m, "cpu MHz\t\t: %u.%03u\n", freq / 1000, (freq % 1000)); > } > > /* Cache size */ > diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c > index 418236fef172..6f45684483c4 100644 > --- a/drivers/cpufreq/cpufreq.c > +++ b/drivers/cpufreq/cpufreq.c > @@ -728,18 +728,18 @@ show_one(cpuinfo_transition_latency, cpuinfo.transition_latency); > show_one(scaling_min_freq, min); > show_one(scaling_max_freq, max); > > -__weak unsigned int arch_freq_get_on_cpu(int cpu) > +__weak int arch_freq_get_on_cpu(int cpu) > { > - return 0; > + return -EOPNOTSUPP; > } > > static ssize_t show_scaling_cur_freq(struct cpufreq_policy *policy, char *buf) > { > ssize_t ret; > - unsigned int freq; > + int freq; > > freq = arch_freq_get_on_cpu(policy->cpu); > - if (freq) > + if (freq > 0) > ret = sysfs_emit(buf, "%u\n", freq); > else if (cpufreq_driver->setpolicy && cpufreq_driver->get) > ret = sysfs_emit(buf, "%u\n", cpufreq_driver->get(policy->cpu)); > diff --git a/include/linux/cpufreq.h b/include/linux/cpufreq.h > index 7fe0981a7e46..02fd4746231d 100644 > --- a/include/linux/cpufreq.h > +++ b/include/linux/cpufreq.h > @@ -1184,7 +1184,7 @@ static inline int of_perf_domain_get_sharing_cpumask(int pcpu, const char *list_ > } > #endif > > -extern unsigned int arch_freq_get_on_cpu(int cpu); > +extern int arch_freq_get_on_cpu(int cpu); > > #ifndef arch_set_freq_scale > static __always_inline Looks good to me. Reviewed-by: Prasanna Kumar T S M