From mboxrd@z Thu Jan 1 00:00:00 1970 From: Viresh Kumar Subject: Re: [PATCH] acpi-cpufreq: use same acpi_cpufreq_data if policy is shared Date: Fri, 3 Jul 2015 14:16:57 +0530 Message-ID: <20150703084657.GB23297@linux> References: <5596414C.4090106@intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from mail-pd0-f172.google.com ([209.85.192.172]:36188 "EHLO mail-pd0-f172.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752162AbbGCIrD (ORCPT ); Fri, 3 Jul 2015 04:47:03 -0400 Received: by pdcu2 with SMTP id u2so61348405pdc.3 for ; Fri, 03 Jul 2015 01:47:02 -0700 (PDT) Content-Disposition: inline In-Reply-To: <5596414C.4090106@intel.com> Sender: linux-pm-owner@vger.kernel.org List-Id: linux-pm@vger.kernel.org To: Pan Xinhui Cc: linux-pm@vger.kernel.org, "linux-kernel@vger.kernel.org" , rjw@rjwysocki.net, "mnipxh@163.com" , "yanmin_zhang@linux.intel.com" On 03-07-15, 16:01, Pan Xinhui wrote: > > cpufreq core will mark all cpus in policy->cpus as initialized > by setting percpu cpufreq_cpu_data = policy. > However in acpi-cpufreq, we did not set percpu acpi_cpufreq_data for > all cpus in policy->cpus. > That will cause a issue that when we call get_cur_freq_on_cpu for a > cpu, it returns zero instead of a correct value. > > So we shared acpi_cpufreq_data for all those cpus in policy->cpus. > > Signed-off-by: xinhuix.pan > --- > drivers/cpufreq/acpi-cpufreq.c | 14 ++++++++++++-- > 1 file changed, 12 insertions(+), 2 deletions(-) > > diff --git a/drivers/cpufreq/acpi-cpufreq.c b/drivers/cpufreq/acpi-cpufreq.c > index 0136dfc..6c6dc97 100644 > --- a/drivers/cpufreq/acpi-cpufreq.c > +++ b/drivers/cpufreq/acpi-cpufreq.c > @@ -673,6 +673,7 @@ static int acpi_cpufreq_cpu_init(struct cpufreq_policy *policy) > } > > data->acpi_data = per_cpu_ptr(acpi_perf_data, cpu); > + cpumask_copy(policy->cpus, cpumask_of(cpu)); This is already done by cpufreq-core before calling ->init() and so isn't required. > per_cpu(acfreq_data, cpu) = data; > > if (cpu_has(c, X86_FEATURE_CONSTANT_TSC)) > @@ -712,6 +713,10 @@ static int acpi_cpufreq_cpu_init(struct cpufreq_policy *policy) > } > #endif > > + for_each_cpu(i, policy->cpus) { > + per_cpu(acfreq_data, i) = data; > + } > + > /* capability check */ > if (perf->state_count <= 1) { > pr_debug("No P-States\n"); > @@ -843,7 +848,9 @@ err_free_mask: > free_cpumask_var(data->freqdomain_cpus); > err_free: > kfree(data); > - per_cpu(acfreq_data, cpu) = NULL; > + for_each_cpu(i, policy->cpus) { > + per_cpu(acfreq_data, i) = NULL; > + } The per-cpu thing is basically wrong to start with. cpufreq-policy has a field: 'driver_data', which can be used to replace this acfreq_data. Probably use that and things will get fixed by themselves. -- viresh