[PATCH 2/2 V2] CPUFreq: Add new sysfs attribute freqdomain_cpus for acpi-freq driver

[PATCH 2/2 V2] CPUFreq: Add new sysfs attribute freqdomain_cpus for acpi-freq driver

[Lan Tianyu]

Commit aa77a52 and fcf8058 changes the content of "related_cpus" and user
space can't get cpus which are in the same hardware coordination cpu domain
(These info are provided by ACPI AML method _PSD) via "related_cpus". This
change affects some users of original "related_cpus".

This patch is to add a new sysfs attribute "freqdomian_cpus" for acpi-cpufreq
driver which exposes all cpus in the same domain regardless of hardware or
software coordination to make up the info loss of previous change.

Reference:https://bugzilla.kernel.org/show_bug.cgi?id=58761
Reported-by: Jean-Philippe Halimi <jean-philippe.halimi@exascale-computing.eu>
Signed-off-by: Lan Tianyu <tianyu.lan@intel.com>
---
Change since v1:
     Create new file acpi-cpufreq.txt under Documentation/cpu-freq and
move new attribute descriptor to it.
     Add new field freqdomain_cpus in struct acpi_cpufreq_data and record
cpu domain info in it. For AMD case, use sibling cpus info to overwrite
cpu domain info from ACPI.        

 Documentation/cpu-freq/acpi-cpufreq.txt |    7 +++++++
 drivers/cpufreq/acpi-cpufreq.c          |   23 ++++++++++++++++++++++-
 drivers/cpufreq/cpufreq.c               |    7 ++++---
 include/linux/cpufreq.h                 |    3 +++
 4 files changed, 36 insertions(+), 4 deletions(-)
 create mode 100644 Documentation/cpu-freq/acpi-cpufreq.txt

diff --git a/Documentation/cpu-freq/acpi-cpufreq.txt b/Documentation/cpu-freq/acpi-cpufreq.txt
new file mode 100644
index 0000000..9c59d09
--- /dev/null
+++ b/Documentation/cpu-freq/acpi-cpufreq.txt
@@ -0,0 +1,7 @@
+Sysfs interface
+---------------------------
+(Interface locates in the directory /sys/devices/system/cpu/cpuN/cpufreq)
+
+freqdomain_cpus :               List of Online + Offline CPUs in same CPU dependency
+                                domain.
+
diff --git a/drivers/cpufreq/acpi-cpufreq.c b/drivers/cpufreq/acpi-cpufreq.c
index f4fef0a..3926402 100644
--- a/drivers/cpufreq/acpi-cpufreq.c
+++ b/drivers/cpufreq/acpi-cpufreq.c
@@ -70,6 +70,7 @@ struct acpi_cpufreq_data {
 	struct cpufreq_frequency_table *freq_table;
 	unsigned int resume;
 	unsigned int cpu_feature;
+	cpumask_var_t freqdomain_cpus;
 };
 
 static DEFINE_PER_CPU(struct acpi_cpufreq_data *, acfreq_data);
@@ -176,6 +177,15 @@ static struct global_attr global_boost = __ATTR(boost, 0644,
 						show_global_boost,
 						store_global_boost);
 
+static ssize_t show_freqdomain_cpus(struct cpufreq_policy *policy, char *buf)
+{
+	struct acpi_cpufreq_data *data = per_cpu(acfreq_data, policy->cpu);
+
+	return cpufreq_show_cpus(data->freqdomain_cpus, buf);
+}
+
+cpufreq_freq_attr_ro(freqdomain_cpus);
+
 #ifdef CONFIG_X86_ACPI_CPUFREQ_CPB
 static ssize_t store_cpb(struct cpufreq_policy *policy, const char *buf,
 			 size_t count)
@@ -704,6 +714,11 @@ static int acpi_cpufreq_cpu_init(struct cpufreq_policy *policy)
 	if (!data)
 		return -ENOMEM;
 
+	if (!zalloc_cpumask_var(&data->freqdomain_cpus, GFP_KERNEL)) {
+		result = -ENOMEM;
+		goto err_free;
+	}
+
 	data->acpi_data = per_cpu_ptr(acpi_perf_data, cpu);
 	per_cpu(acfreq_data, cpu) = data;
 
@@ -712,7 +727,7 @@ static int acpi_cpufreq_cpu_init(struct cpufreq_policy *policy)
 
 	result = acpi_processor_register_performance(data->acpi_data, cpu);
 	if (result)
-		goto err_free;
+		goto err_free_mask;
 
 	perf = data->acpi_data;
 	policy->shared_type = perf->shared_type;
@@ -725,6 +740,7 @@ static int acpi_cpufreq_cpu_init(struct cpufreq_policy *policy)
 	    policy->shared_type == CPUFREQ_SHARED_TYPE_ANY) {
 		cpumask_copy(policy->cpus, perf->shared_cpu_map);
 	}
+	cpumask_copy(data->freqdomain_cpus, perf->shared_cpu_map);
 
 #ifdef CONFIG_SMP
 	dmi_check_system(sw_any_bug_dmi_table);
@@ -736,6 +752,7 @@ static int acpi_cpufreq_cpu_init(struct cpufreq_policy *policy)
 	if (check_amd_hwpstate_cpu(cpu) && !acpi_pstate_strict) {
 		cpumask_clear(policy->cpus);
 		cpumask_set_cpu(cpu, policy->cpus);
+		cpumask_copy(data->freqdomain_cpus, cpu_sibling_mask(cpu));
 		policy->shared_type = CPUFREQ_SHARED_TYPE_HW;
 		pr_info_once(PFX "overriding BIOS provided _PSD data\n");
 	}
@@ -870,6 +887,8 @@ err_freqfree:
 	kfree(data->freq_table);
 err_unreg:
 	acpi_processor_unregister_performance(perf, cpu);
+err_free_mask:
+	free_cpumask_var(data->freqdomain_cpus);
 err_free:
 	kfree(data);
 	per_cpu(acfreq_data, cpu) = NULL;
@@ -888,6 +907,7 @@ static int acpi_cpufreq_cpu_exit(struct cpufreq_policy *policy)
 		per_cpu(acfreq_data, policy->cpu) = NULL;
 		acpi_processor_unregister_performance(data->acpi_data,
 						      policy->cpu);
+		free_cpumask_var(data->freqdomain_cpus);
 		kfree(data->freq_table);
 		kfree(data);
 	}
@@ -908,6 +928,7 @@ static int acpi_cpufreq_resume(struct cpufreq_policy *policy)
 
 static struct freq_attr *acpi_cpufreq_attr[] = {
 	&cpufreq_freq_attr_scaling_available_freqs,
+	&freqdomain_cpus,
 	NULL,	/* this is a placeholder for cpb, do not remove */
 	NULL,
 };
diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index d976e22..adf12a9f 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -573,7 +573,7 @@ out:
 	return i;
 }
 
-static ssize_t show_cpus(const struct cpumask *mask, char *buf)
+ssize_t cpufreq_show_cpus(const struct cpumask *mask, char *buf)
 {
 	ssize_t i = 0;
 	unsigned int cpu;
@@ -588,6 +588,7 @@ static ssize_t show_cpus(const struct cpumask *mask, char *buf)
 	i += sprintf(&buf[i], "\n");
 	return i;
 }
+EXPORT_SYMBOL_GPL(cpufreq_show_cpus);
 
 /**
  * show_related_cpus - show the CPUs affected by each transition even if
@@ -595,7 +596,7 @@ static ssize_t show_cpus(const struct cpumask *mask, char *buf)
  */
 static ssize_t show_related_cpus(struct cpufreq_policy *policy, char *buf)
 {
-	return show_cpus(policy->related_cpus, buf);
+	return cpufreq_show_cpus(policy->related_cpus, buf);
 }
 
 /**
@@ -603,7 +604,7 @@ static ssize_t show_related_cpus(struct cpufreq_policy *policy, char *buf)
  */
 static ssize_t show_affected_cpus(struct cpufreq_policy *policy, char *buf)
 {
-	return show_cpus(policy->cpus, buf);
+	return cpufreq_show_cpus(policy->cpus, buf);
 }
 
 static ssize_t store_scaling_setspeed(struct cpufreq_policy *policy,
diff --git a/include/linux/cpufreq.h b/include/linux/cpufreq.h
index 3c7ee2f..5fedb6c 100644
--- a/include/linux/cpufreq.h
+++ b/include/linux/cpufreq.h
@@ -438,4 +438,7 @@ void cpufreq_frequency_table_get_attr(struct cpufreq_frequency_table *table,
 void cpufreq_frequency_table_update_policy_cpu(struct cpufreq_policy *policy);
 
 void cpufreq_frequency_table_put_attr(unsigned int cpu);
+
+ssize_t cpufreq_show_cpus(const struct cpumask *mask, char *buf);
+
 #endif /* _LINUX_CPUFREQ_H */
-- 
1.7.10.4

Re: [PATCH 2/2 V2] CPUFreq: Add new sysfs attribute freqdomain_cpus for acpi-freq driver

[Rafael J. Wysocki]

On Wednesday, June 26, 2013 08:38:24 PM Lan Tianyu wrote:
> Commit aa77a52 and fcf8058 changes the content of "related_cpus" and user
> space can't get cpus which are in the same hardware coordination cpu domain
> (These info are provided by ACPI AML method _PSD) via "related_cpus". This
> change affects some users of original "related_cpus".
> 
> This patch is to add a new sysfs attribute "freqdomian_cpus" for acpi-cpufreq
> driver which exposes all cpus in the same domain regardless of hardware or
> software coordination to make up the info loss of previous change.
> 
> Reference:https://bugzilla.kernel.org/show_bug.cgi?id=58761
> Reported-by: Jean-Philippe Halimi <jean-philippe.halimi@exascale-computing.eu>

It looks from the bug entry that this has been tested too?

> Signed-off-by: Lan Tianyu <tianyu.lan@intel.com>
> ---
> Change since v1:
>      Create new file acpi-cpufreq.txt under Documentation/cpu-freq and
> move new attribute descriptor to it.
>      Add new field freqdomain_cpus in struct acpi_cpufreq_data and record
> cpu domain info in it. For AMD case, use sibling cpus info to overwrite
> cpu domain info from ACPI.        
> 
>  Documentation/cpu-freq/acpi-cpufreq.txt |    7 +++++++
>  drivers/cpufreq/acpi-cpufreq.c          |   23 ++++++++++++++++++++++-
>  drivers/cpufreq/cpufreq.c               |    7 ++++---
>  include/linux/cpufreq.h                 |    3 +++
>  4 files changed, 36 insertions(+), 4 deletions(-)
>  create mode 100644 Documentation/cpu-freq/acpi-cpufreq.txt
> 
> diff --git a/Documentation/cpu-freq/acpi-cpufreq.txt b/Documentation/cpu-freq/acpi-cpufreq.txt
> new file mode 100644
> index 0000000..9c59d09
> --- /dev/null
> +++ b/Documentation/cpu-freq/acpi-cpufreq.txt
> @@ -0,0 +1,7 @@
> +Sysfs interface
> +---------------------------
> +(Interface locates in the directory /sys/devices/system/cpu/cpuN/cpufreq)
> +
> +freqdomain_cpus :               List of Online + Offline CPUs in same CPU dependency
> +                                domain.
> +

No, this is confusing.

Please document it in Documentation/ABI/testing/sysfs-devices-system-cpu below
the /sys/devices/system/cpu/cpu#/cpufreq/* thing, but please write in the
description that this is only present if the acpi-cpufreq driver is in use.

Thanks,
Rafael


> diff --git a/drivers/cpufreq/acpi-cpufreq.c b/drivers/cpufreq/acpi-cpufreq.c
> index f4fef0a..3926402 100644
> --- a/drivers/cpufreq/acpi-cpufreq.c
> +++ b/drivers/cpufreq/acpi-cpufreq.c
> @@ -70,6 +70,7 @@ struct acpi_cpufreq_data {
>  	struct cpufreq_frequency_table *freq_table;
>  	unsigned int resume;
>  	unsigned int cpu_feature;
> +	cpumask_var_t freqdomain_cpus;
>  };
>  
>  static DEFINE_PER_CPU(struct acpi_cpufreq_data *, acfreq_data);
> @@ -176,6 +177,15 @@ static struct global_attr global_boost = __ATTR(boost, 0644,
>  						show_global_boost,
>  						store_global_boost);
>  
> +static ssize_t show_freqdomain_cpus(struct cpufreq_policy *policy, char *buf)
> +{
> +	struct acpi_cpufreq_data *data = per_cpu(acfreq_data, policy->cpu);
> +
> +	return cpufreq_show_cpus(data->freqdomain_cpus, buf);
> +}
> +
> +cpufreq_freq_attr_ro(freqdomain_cpus);
> +
>  #ifdef CONFIG_X86_ACPI_CPUFREQ_CPB
>  static ssize_t store_cpb(struct cpufreq_policy *policy, const char *buf,
>  			 size_t count)
> @@ -704,6 +714,11 @@ static int acpi_cpufreq_cpu_init(struct cpufreq_policy *policy)
>  	if (!data)
>  		return -ENOMEM;
>  
> +	if (!zalloc_cpumask_var(&data->freqdomain_cpus, GFP_KERNEL)) {
> +		result = -ENOMEM;
> +		goto err_free;
> +	}
> +
>  	data->acpi_data = per_cpu_ptr(acpi_perf_data, cpu);
>  	per_cpu(acfreq_data, cpu) = data;
>  
> @@ -712,7 +727,7 @@ static int acpi_cpufreq_cpu_init(struct cpufreq_policy *policy)
>  
>  	result = acpi_processor_register_performance(data->acpi_data, cpu);
>  	if (result)
> -		goto err_free;
> +		goto err_free_mask;
>  
>  	perf = data->acpi_data;
>  	policy->shared_type = perf->shared_type;
> @@ -725,6 +740,7 @@ static int acpi_cpufreq_cpu_init(struct cpufreq_policy *policy)
>  	    policy->shared_type == CPUFREQ_SHARED_TYPE_ANY) {
>  		cpumask_copy(policy->cpus, perf->shared_cpu_map);
>  	}
> +	cpumask_copy(data->freqdomain_cpus, perf->shared_cpu_map);
>  
>  #ifdef CONFIG_SMP
>  	dmi_check_system(sw_any_bug_dmi_table);
> @@ -736,6 +752,7 @@ static int acpi_cpufreq_cpu_init(struct cpufreq_policy *policy)
>  	if (check_amd_hwpstate_cpu(cpu) && !acpi_pstate_strict) {
>  		cpumask_clear(policy->cpus);
>  		cpumask_set_cpu(cpu, policy->cpus);
> +		cpumask_copy(data->freqdomain_cpus, cpu_sibling_mask(cpu));
>  		policy->shared_type = CPUFREQ_SHARED_TYPE_HW;
>  		pr_info_once(PFX "overriding BIOS provided _PSD data\n");
>  	}
> @@ -870,6 +887,8 @@ err_freqfree:
>  	kfree(data->freq_table);
>  err_unreg:
>  	acpi_processor_unregister_performance(perf, cpu);
> +err_free_mask:
> +	free_cpumask_var(data->freqdomain_cpus);
>  err_free:
>  	kfree(data);
>  	per_cpu(acfreq_data, cpu) = NULL;
> @@ -888,6 +907,7 @@ static int acpi_cpufreq_cpu_exit(struct cpufreq_policy *policy)
>  		per_cpu(acfreq_data, policy->cpu) = NULL;
>  		acpi_processor_unregister_performance(data->acpi_data,
>  						      policy->cpu);
> +		free_cpumask_var(data->freqdomain_cpus);
>  		kfree(data->freq_table);
>  		kfree(data);
>  	}
> @@ -908,6 +928,7 @@ static int acpi_cpufreq_resume(struct cpufreq_policy *policy)
>  
>  static struct freq_attr *acpi_cpufreq_attr[] = {
>  	&cpufreq_freq_attr_scaling_available_freqs,
> +	&freqdomain_cpus,
>  	NULL,	/* this is a placeholder for cpb, do not remove */
>  	NULL,
>  };
> diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
> index d976e22..adf12a9f 100644
> --- a/drivers/cpufreq/cpufreq.c
> +++ b/drivers/cpufreq/cpufreq.c
> @@ -573,7 +573,7 @@ out:
>  	return i;
>  }
>  
> -static ssize_t show_cpus(const struct cpumask *mask, char *buf)
> +ssize_t cpufreq_show_cpus(const struct cpumask *mask, char *buf)
>  {
>  	ssize_t i = 0;
>  	unsigned int cpu;
> @@ -588,6 +588,7 @@ static ssize_t show_cpus(const struct cpumask *mask, char *buf)
>  	i += sprintf(&buf[i], "\n");
>  	return i;
>  }
> +EXPORT_SYMBOL_GPL(cpufreq_show_cpus);
>  
>  /**
>   * show_related_cpus - show the CPUs affected by each transition even if
> @@ -595,7 +596,7 @@ static ssize_t show_cpus(const struct cpumask *mask, char *buf)
>   */
>  static ssize_t show_related_cpus(struct cpufreq_policy *policy, char *buf)
>  {
> -	return show_cpus(policy->related_cpus, buf);
> +	return cpufreq_show_cpus(policy->related_cpus, buf);
>  }
>  
>  /**
> @@ -603,7 +604,7 @@ static ssize_t show_related_cpus(struct cpufreq_policy *policy, char *buf)
>   */
>  static ssize_t show_affected_cpus(struct cpufreq_policy *policy, char *buf)
>  {
> -	return show_cpus(policy->cpus, buf);
> +	return cpufreq_show_cpus(policy->cpus, buf);
>  }
>  
>  static ssize_t store_scaling_setspeed(struct cpufreq_policy *policy,
> diff --git a/include/linux/cpufreq.h b/include/linux/cpufreq.h
> index 3c7ee2f..5fedb6c 100644
> --- a/include/linux/cpufreq.h
> +++ b/include/linux/cpufreq.h
> @@ -438,4 +438,7 @@ void cpufreq_frequency_table_get_attr(struct cpufreq_frequency_table *table,
>  void cpufreq_frequency_table_update_policy_cpu(struct cpufreq_policy *policy);
>  
>  void cpufreq_frequency_table_put_attr(unsigned int cpu);
> +
> +ssize_t cpufreq_show_cpus(const struct cpumask *mask, char *buf);
> +
>  #endif /* _LINUX_CPUFREQ_H */
> 
-- 
I speak only for myself.
Rafael J. Wysocki, Intel Open Source Technology Center.

Re: [PATCH 2/2 V2] CPUFreq: Add new sysfs attribute freqdomain_cpus for acpi-freq driver

[Lan Tianyu]

On 2013年06月27日 08:10, Rafael J. Wysocki wrote:
> On Wednesday, June 26, 2013 08:38:24 PM Lan Tianyu wrote:
>> Commit aa77a52 and fcf8058 changes the content of "related_cpus" and user
>> space can't get cpus which are in the same hardware coordination cpu domain
>> (These info are provided by ACPI AML method _PSD) via "related_cpus". This
>> change affects some users of original "related_cpus".
>>
>> This patch is to add a new sysfs attribute "freqdomian_cpus" for acpi-cpufreq
>> driver which exposes all cpus in the same domain regardless of hardware or
>> software coordination to make up the info loss of previous change.
>>
>> Reference:https://bugzilla.kernel.org/show_bug.cgi?id=58761
>> Reported-by: Jean-Philippe Halimi <jean-philippe.halimi@exascale-computing.eu>
> 
> It looks from the bug entry that this has been tested too?

V1 has been tested by Jean-Philippe but for V2, I have changed some
codes. So I didn't add tested-by.

> 
>> Signed-off-by: Lan Tianyu <tianyu.lan@intel.com>
>> ---
>> Change since v1:
>>      Create new file acpi-cpufreq.txt under Documentation/cpu-freq and
>> move new attribute descriptor to it.
>>      Add new field freqdomain_cpus in struct acpi_cpufreq_data and record
>> cpu domain info in it. For AMD case, use sibling cpus info to overwrite
>> cpu domain info from ACPI.        
>>
>>  Documentation/cpu-freq/acpi-cpufreq.txt |    7 +++++++
>>  drivers/cpufreq/acpi-cpufreq.c          |   23 ++++++++++++++++++++++-
>>  drivers/cpufreq/cpufreq.c               |    7 ++++---
>>  include/linux/cpufreq.h                 |    3 +++
>>  4 files changed, 36 insertions(+), 4 deletions(-)
>>  create mode 100644 Documentation/cpu-freq/acpi-cpufreq.txt
>>
>> diff --git a/Documentation/cpu-freq/acpi-cpufreq.txt b/Documentation/cpu-freq/acpi-cpufreq.txt
>> new file mode 100644
>> index 0000000..9c59d09
>> --- /dev/null
>> +++ b/Documentation/cpu-freq/acpi-cpufreq.txt
>> @@ -0,0 +1,7 @@
>> +Sysfs interface
>> +---------------------------
>> +(Interface locates in the directory /sys/devices/system/cpu/cpuN/cpufreq)
>> +
>> +freqdomain_cpus :               List of Online + Offline CPUs in same CPU dependency
>> +                                domain.
>> +
> 
> No, this is confusing.
>

Ok.

> Please document it in Documentation/ABI/testing/sysfs-devices-system-cpu below
> the /sys/devices/system/cpu/cpu#/cpufreq/* thing, but please write in the
> description that this is only present if the acpi-cpufreq driver is in use.

I will update soon.

> 
> Thanks,
> Rafael
> 
> 
>> diff --git a/drivers/cpufreq/acpi-cpufreq.c b/drivers/cpufreq/acpi-cpufreq.c
>> index f4fef0a..3926402 100644
>> --- a/drivers/cpufreq/acpi-cpufreq.c
>> +++ b/drivers/cpufreq/acpi-cpufreq.c
>> @@ -70,6 +70,7 @@ struct acpi_cpufreq_data {
>>  	struct cpufreq_frequency_table *freq_table;
>>  	unsigned int resume;
>>  	unsigned int cpu_feature;
>> +	cpumask_var_t freqdomain_cpus;
>>  };
>>  
>>  static DEFINE_PER_CPU(struct acpi_cpufreq_data *, acfreq_data);
>> @@ -176,6 +177,15 @@ static struct global_attr global_boost = __ATTR(boost, 0644,
>>  						show_global_boost,
>>  						store_global_boost);
>>  
>> +static ssize_t show_freqdomain_cpus(struct cpufreq_policy *policy, char *buf)
>> +{
>> +	struct acpi_cpufreq_data *data = per_cpu(acfreq_data, policy->cpu);
>> +
>> +	return cpufreq_show_cpus(data->freqdomain_cpus, buf);
>> +}
>> +
>> +cpufreq_freq_attr_ro(freqdomain_cpus);
>> +
>>  #ifdef CONFIG_X86_ACPI_CPUFREQ_CPB
>>  static ssize_t store_cpb(struct cpufreq_policy *policy, const char *buf,
>>  			 size_t count)
>> @@ -704,6 +714,11 @@ static int acpi_cpufreq_cpu_init(struct cpufreq_policy *policy)
>>  	if (!data)
>>  		return -ENOMEM;
>>  
>> +	if (!zalloc_cpumask_var(&data->freqdomain_cpus, GFP_KERNEL)) {
>> +		result = -ENOMEM;
>> +		goto err_free;
>> +	}
>> +
>>  	data->acpi_data = per_cpu_ptr(acpi_perf_data, cpu);
>>  	per_cpu(acfreq_data, cpu) = data;
>>  
>> @@ -712,7 +727,7 @@ static int acpi_cpufreq_cpu_init(struct cpufreq_policy *policy)
>>  
>>  	result = acpi_processor_register_performance(data->acpi_data, cpu);
>>  	if (result)
>> -		goto err_free;
>> +		goto err_free_mask;
>>  
>>  	perf = data->acpi_data;
>>  	policy->shared_type = perf->shared_type;
>> @@ -725,6 +740,7 @@ static int acpi_cpufreq_cpu_init(struct cpufreq_policy *policy)
>>  	    policy->shared_type == CPUFREQ_SHARED_TYPE_ANY) {
>>  		cpumask_copy(policy->cpus, perf->shared_cpu_map);
>>  	}
>> +	cpumask_copy(data->freqdomain_cpus, perf->shared_cpu_map);
>>  
>>  #ifdef CONFIG_SMP
>>  	dmi_check_system(sw_any_bug_dmi_table);
>> @@ -736,6 +752,7 @@ static int acpi_cpufreq_cpu_init(struct cpufreq_policy *policy)
>>  	if (check_amd_hwpstate_cpu(cpu) && !acpi_pstate_strict) {
>>  		cpumask_clear(policy->cpus);
>>  		cpumask_set_cpu(cpu, policy->cpus);
>> +		cpumask_copy(data->freqdomain_cpus, cpu_sibling_mask(cpu));
>>  		policy->shared_type = CPUFREQ_SHARED_TYPE_HW;
>>  		pr_info_once(PFX "overriding BIOS provided _PSD data\n");
>>  	}
>> @@ -870,6 +887,8 @@ err_freqfree:
>>  	kfree(data->freq_table);
>>  err_unreg:
>>  	acpi_processor_unregister_performance(perf, cpu);
>> +err_free_mask:
>> +	free_cpumask_var(data->freqdomain_cpus);
>>  err_free:
>>  	kfree(data);
>>  	per_cpu(acfreq_data, cpu) = NULL;
>> @@ -888,6 +907,7 @@ static int acpi_cpufreq_cpu_exit(struct cpufreq_policy *policy)
>>  		per_cpu(acfreq_data, policy->cpu) = NULL;
>>  		acpi_processor_unregister_performance(data->acpi_data,
>>  						      policy->cpu);
>> +		free_cpumask_var(data->freqdomain_cpus);
>>  		kfree(data->freq_table);
>>  		kfree(data);
>>  	}
>> @@ -908,6 +928,7 @@ static int acpi_cpufreq_resume(struct cpufreq_policy *policy)
>>  
>>  static struct freq_attr *acpi_cpufreq_attr[] = {
>>  	&cpufreq_freq_attr_scaling_available_freqs,
>> +	&freqdomain_cpus,
>>  	NULL,	/* this is a placeholder for cpb, do not remove */
>>  	NULL,
>>  };
>> diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
>> index d976e22..adf12a9f 100644
>> --- a/drivers/cpufreq/cpufreq.c
>> +++ b/drivers/cpufreq/cpufreq.c
>> @@ -573,7 +573,7 @@ out:
>>  	return i;
>>  }
>>  
>> -static ssize_t show_cpus(const struct cpumask *mask, char *buf)
>> +ssize_t cpufreq_show_cpus(const struct cpumask *mask, char *buf)
>>  {
>>  	ssize_t i = 0;
>>  	unsigned int cpu;
>> @@ -588,6 +588,7 @@ static ssize_t show_cpus(const struct cpumask *mask, char *buf)
>>  	i += sprintf(&buf[i], "\n");
>>  	return i;
>>  }
>> +EXPORT_SYMBOL_GPL(cpufreq_show_cpus);
>>  
>>  /**
>>   * show_related_cpus - show the CPUs affected by each transition even if
>> @@ -595,7 +596,7 @@ static ssize_t show_cpus(const struct cpumask *mask, char *buf)
>>   */
>>  static ssize_t show_related_cpus(struct cpufreq_policy *policy, char *buf)
>>  {
>> -	return show_cpus(policy->related_cpus, buf);
>> +	return cpufreq_show_cpus(policy->related_cpus, buf);
>>  }
>>  
>>  /**
>> @@ -603,7 +604,7 @@ static ssize_t show_related_cpus(struct cpufreq_policy *policy, char *buf)
>>   */
>>  static ssize_t show_affected_cpus(struct cpufreq_policy *policy, char *buf)
>>  {
>> -	return show_cpus(policy->cpus, buf);
>> +	return cpufreq_show_cpus(policy->cpus, buf);
>>  }
>>  
>>  static ssize_t store_scaling_setspeed(struct cpufreq_policy *policy,
>> diff --git a/include/linux/cpufreq.h b/include/linux/cpufreq.h
>> index 3c7ee2f..5fedb6c 100644
>> --- a/include/linux/cpufreq.h
>> +++ b/include/linux/cpufreq.h
>> @@ -438,4 +438,7 @@ void cpufreq_frequency_table_get_attr(struct cpufreq_frequency_table *table,
>>  void cpufreq_frequency_table_update_policy_cpu(struct cpufreq_policy *policy);
>>  
>>  void cpufreq_frequency_table_put_attr(unsigned int cpu);
>> +
>> +ssize_t cpufreq_show_cpus(const struct cpumask *mask, char *buf);
>> +
>>  #endif /* _LINUX_CPUFREQ_H */
>>


-- 
Best regards
Tianyu Lan

Re: [PATCH 2/2 V2] CPUFreq: Add new sysfs attribute freqdomain_cpus for acpi-freq driver

[Viresh Kumar]

On 26 June 2013 18:08, Lan Tianyu <tianyu.lan@intel.com> wrote:
> diff --git a/Documentation/cpu-freq/acpi-cpufreq.txt b/Documentation/cpu-freq/acpi-cpufreq.txt
> new file mode 100644
> index 0000000..9c59d09
> --- /dev/null
> +++ b/Documentation/cpu-freq/acpi-cpufreq.txt
> @@ -0,0 +1,7 @@
> +Sysfs interface
> +---------------------------
> +(Interface locates in the directory /sys/devices/system/cpu/cpuN/cpufreq)
> +
> +freqdomain_cpus :               List of Online + Offline CPUs in same CPU dependency
> +                                domain.
> +

Apart from the comments from Rafael, this must be described a bit
more. We must write here how is it different than related_cpus.

Write: freqdomain_cpus are the list of cpus (online+offline) that share
same clock/freq domain at hardware level. This information might
be hidden from cpufreq core and so related_cpus can have different
value compared to this. This is not used by kernel but userspace
DVFS controllers to get better power/performance values for platforms
using acpi-cpufreq.c driver.

Re: [PATCH 2/2 V2] CPUFreq: Add new sysfs attribute freqdomain_cpus for acpi-freq driver

[Lan Tianyu]

On 2013年06月27日 13:24, Viresh Kumar wrote:
> On 26 June 2013 18:08, Lan Tianyu <tianyu.lan@intel.com> wrote:
>> diff --git a/Documentation/cpu-freq/acpi-cpufreq.txt b/Documentation/cpu-freq/acpi-cpufreq.txt
>> new file mode 100644
>> index 0000000..9c59d09
>> --- /dev/null
>> +++ b/Documentation/cpu-freq/acpi-cpufreq.txt
>> @@ -0,0 +1,7 @@
>> +Sysfs interface
>> +---------------------------
>> +(Interface locates in the directory /sys/devices/system/cpu/cpuN/cpufreq)
>> +
>> +freqdomain_cpus :               List of Online + Offline CPUs in same CPU dependency
>> +                                domain.
>> +
> 
> Apart from the comments from Rafael, this must be described a bit
> more. We must write here how is it different than related_cpus.
> 
> Write: freqdomain_cpus are the list of cpus (online+offline) that share
> same clock/freq domain at hardware level. This information might
> be hidden from cpufreq core and so related_cpus can have different
> value compared to this. This is not used by kernel but userspace
> DVFS controllers to get better power/performance values for platforms
> using acpi-cpufreq.c driver.
> 
Thanks for your comments. I will add this in my patch.


-- 
Best regards
Tianyu Lan