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[PATCH v5 01/11] cpufreq: CPPC: Add generic helpers for sysfs show/store

Sumit Gupta posted 11 patches 1 month, 2 weeks ago
There is a newer version of this series
[PATCH v5 01/11] cpufreq: CPPC: Add generic helpers for sysfs show/store
Posted by Sumit Gupta 1 month, 2 weeks ago 
Add generic show/store helper functions for u64 sysfs attributes:
- cppc_cpufreq_sysfs_show_u64()
- cppc_cpufreq_sysfs_store_u64()

Refactor auto_act_window and energy_performance_preference_val
attributes to use these helpers, eliminating code duplication.

No functional changes.

Signed-off-by: Sumit Gupta <sumitg@nvidia.com>
---
 drivers/cpufreq/cppc_cpufreq.c | 71 +++++++++++++++-------------------
 1 file changed, 31 insertions(+), 40 deletions(-)

diff --git a/drivers/cpufreq/cppc_cpufreq.c b/drivers/cpufreq/cppc_cpufreq.c
index 9eac77c4f294..7c26ce554e29 100644
--- a/drivers/cpufreq/cppc_cpufreq.c
+++ b/drivers/cpufreq/cppc_cpufreq.c
@@ -831,72 +831,63 @@ static ssize_t store_auto_select(struct cpufreq_policy *policy,
 	return count;
 }
 
-static ssize_t show_auto_act_window(struct cpufreq_policy *policy, char *buf)
+static ssize_t cppc_cpufreq_sysfs_show_u64(unsigned int cpu,
+					   int (*get_func)(int, u64 *),
+					   char *buf)
 {
 	u64 val;
-	int ret;
-
-	ret = cppc_get_auto_act_window(policy->cpu, &val);
+	int ret = get_func((int)cpu, &val);
 
-	/* show "<unsupported>" when this register is not supported by cpc */
 	if (ret == -EOPNOTSUPP)
 		return sysfs_emit(buf, "<unsupported>\n");
-
 	if (ret)
 		return ret;
 
 	return sysfs_emit(buf, "%llu\n", val);
 }
 
-static ssize_t store_auto_act_window(struct cpufreq_policy *policy,
-				     const char *buf, size_t count)
+static ssize_t cppc_cpufreq_sysfs_store_u64(unsigned int cpu,
+					    int (*set_func)(int, u64),
+					    const char *buf, size_t count)
 {
-	u64 usec;
+	u64 val;
 	int ret;
 
-	ret = kstrtou64(buf, 0, &usec);
+	ret = kstrtou64(buf, 0, &val);
 	if (ret)
 		return ret;
 
-	ret = cppc_set_auto_act_window(policy->cpu, usec);
-	if (ret)
-		return ret;
+	ret = set_func((int)cpu, val);
 
-	return count;
+	return ret ? ret : count;
 }
 
-static ssize_t show_energy_performance_preference_val(struct cpufreq_policy *policy, char *buf)
+static ssize_t show_auto_act_window(struct cpufreq_policy *policy, char *buf)
 {
-	u64 val;
-	int ret;
-
-	ret = cppc_get_epp_perf(policy->cpu, &val);
-
-	/* show "<unsupported>" when this register is not supported by cpc */
-	if (ret == -EOPNOTSUPP)
-		return sysfs_emit(buf, "<unsupported>\n");
-
-	if (ret)
-		return ret;
-
-	return sysfs_emit(buf, "%llu\n", val);
+	return cppc_cpufreq_sysfs_show_u64(policy->cpu,
+					   cppc_get_auto_act_window, buf);
 }
 
-static ssize_t store_energy_performance_preference_val(struct cpufreq_policy *policy,
-						       const char *buf, size_t count)
+static ssize_t store_auto_act_window(struct cpufreq_policy *policy,
+				     const char *buf, size_t count)
 {
-	u64 val;
-	int ret;
-
-	ret = kstrtou64(buf, 0, &val);
-	if (ret)
-		return ret;
+	return cppc_cpufreq_sysfs_store_u64(policy->cpu,
+					    cppc_set_auto_act_window,
+					    buf, count);
+}
 
-	ret = cppc_set_epp(policy->cpu, val);
-	if (ret)
-		return ret;
+static ssize_t
+show_energy_performance_preference_val(struct cpufreq_policy *policy, char *buf)
+{
+	return cppc_cpufreq_sysfs_show_u64(policy->cpu, cppc_get_epp_perf, buf);
+}
 
-	return count;
+static ssize_t
+store_energy_performance_preference_val(struct cpufreq_policy *policy,
+					const char *buf, size_t count)
+{
+	return cppc_cpufreq_sysfs_store_u64(policy->cpu, cppc_set_epp,
+					    buf, count);
 }
 
 cpufreq_freq_attr_ro(freqdomain_cpus);
-- 
2.34.1
Re: [PATCH v5 01/11] cpufreq: CPPC: Add generic helpers for sysfs show/store
Posted by zhenglifeng (A) 1 month, 2 weeks ago 
On 2025/12/23 20:12, Sumit Gupta wrote:
> Add generic show/store helper functions for u64 sysfs attributes:
> - cppc_cpufreq_sysfs_show_u64()
> - cppc_cpufreq_sysfs_store_u64()
> 
> Refactor auto_act_window and energy_performance_preference_val
> attributes to use these helpers, eliminating code duplication.

How about adding a macro to generate show_xxx and store_xxx in one line?

Just a suggestion.

> 
> No functional changes.
> 
> Signed-off-by: Sumit Gupta <sumitg@nvidia.com>
> ---
>  drivers/cpufreq/cppc_cpufreq.c | 71 +++++++++++++++-------------------
>  1 file changed, 31 insertions(+), 40 deletions(-)
> 
> diff --git a/drivers/cpufreq/cppc_cpufreq.c b/drivers/cpufreq/cppc_cpufreq.c
> index 9eac77c4f294..7c26ce554e29 100644
> --- a/drivers/cpufreq/cppc_cpufreq.c
> +++ b/drivers/cpufreq/cppc_cpufreq.c
> @@ -831,72 +831,63 @@ static ssize_t store_auto_select(struct cpufreq_policy *policy,
>  	return count;
>  }
>  
> -static ssize_t show_auto_act_window(struct cpufreq_policy *policy, char *buf)
> +static ssize_t cppc_cpufreq_sysfs_show_u64(unsigned int cpu,
> +					   int (*get_func)(int, u64 *),
> +					   char *buf)
>  {
>  	u64 val;
> -	int ret;
> -
> -	ret = cppc_get_auto_act_window(policy->cpu, &val);
> +	int ret = get_func((int)cpu, &val);
>  
> -	/* show "<unsupported>" when this register is not supported by cpc */
>  	if (ret == -EOPNOTSUPP)
>  		return sysfs_emit(buf, "<unsupported>\n");
> -
>  	if (ret)
>  		return ret;
>  
>  	return sysfs_emit(buf, "%llu\n", val);
>  }
>  
> -static ssize_t store_auto_act_window(struct cpufreq_policy *policy,
> -				     const char *buf, size_t count)
> +static ssize_t cppc_cpufreq_sysfs_store_u64(unsigned int cpu,
> +					    int (*set_func)(int, u64),
> +					    const char *buf, size_t count)
>  {
> -	u64 usec;
> +	u64 val;
>  	int ret;
>  
> -	ret = kstrtou64(buf, 0, &usec);
> +	ret = kstrtou64(buf, 0, &val);
>  	if (ret)
>  		return ret;
>  
> -	ret = cppc_set_auto_act_window(policy->cpu, usec);
> -	if (ret)
> -		return ret;
> +	ret = set_func((int)cpu, val);
>  
> -	return count;
> +	return ret ? ret : count;
>  }
>  
> -static ssize_t show_energy_performance_preference_val(struct cpufreq_policy *policy, char *buf)
> +static ssize_t show_auto_act_window(struct cpufreq_policy *policy, char *buf)
>  {
> -	u64 val;
> -	int ret;
> -
> -	ret = cppc_get_epp_perf(policy->cpu, &val);
> -
> -	/* show "<unsupported>" when this register is not supported by cpc */
> -	if (ret == -EOPNOTSUPP)
> -		return sysfs_emit(buf, "<unsupported>\n");
> -
> -	if (ret)
> -		return ret;
> -
> -	return sysfs_emit(buf, "%llu\n", val);
> +	return cppc_cpufreq_sysfs_show_u64(policy->cpu,
> +					   cppc_get_auto_act_window, buf);
>  }
>  
> -static ssize_t store_energy_performance_preference_val(struct cpufreq_policy *policy,
> -						       const char *buf, size_t count)
> +static ssize_t store_auto_act_window(struct cpufreq_policy *policy,
> +				     const char *buf, size_t count)
>  {
> -	u64 val;
> -	int ret;
> -
> -	ret = kstrtou64(buf, 0, &val);
> -	if (ret)
> -		return ret;
> +	return cppc_cpufreq_sysfs_store_u64(policy->cpu,
> +					    cppc_set_auto_act_window,
> +					    buf, count);
> +}
>  
> -	ret = cppc_set_epp(policy->cpu, val);
> -	if (ret)
> -		return ret;
> +static ssize_t
> +show_energy_performance_preference_val(struct cpufreq_policy *policy, char *buf)
> +{
> +	return cppc_cpufreq_sysfs_show_u64(policy->cpu, cppc_get_epp_perf, buf);
> +}
>  
> -	return count;
> +static ssize_t
> +store_energy_performance_preference_val(struct cpufreq_policy *policy,
> +					const char *buf, size_t count)
> +{
> +	return cppc_cpufreq_sysfs_store_u64(policy->cpu, cppc_set_epp,
> +					    buf, count);
>  }
>  
>  cpufreq_freq_attr_ro(freqdomain_cpus);
Re: [PATCH v5 01/11] cpufreq: CPPC: Add generic helpers for sysfs show/store
Posted by Sumit Gupta 1 month ago 
On 25/12/25 09:11, zhenglifeng (A) wrote:
> External email: Use caution opening links or attachments
>
>
> On 2025/12/23 20:12, Sumit Gupta wrote:
>> Add generic show/store helper functions for u64 sysfs attributes:
>> - cppc_cpufreq_sysfs_show_u64()
>> - cppc_cpufreq_sysfs_store_u64()
>>
>> Refactor auto_act_window and energy_performance_preference_val
>> attributes to use these helpers, eliminating code duplication.
> How about adding a macro to generate show_xxx and store_xxx in one line?
>
> Just a suggestion.

will add macro in v6.

Thank you,
Sumit Gupta


>> No functional changes.
>>
>> Signed-off-by: Sumit Gupta <sumitg@nvidia.com>
>> ---
>>   drivers/cpufreq/cppc_cpufreq.c | 71 +++++++++++++++-------------------
>>   1 file changed, 31 insertions(+), 40 deletions(-)
>>
>> diff --git a/drivers/cpufreq/cppc_cpufreq.c b/drivers/cpufreq/cppc_cpufreq.c
>> index 9eac77c4f294..7c26ce554e29 100644
>> --- a/drivers/cpufreq/cppc_cpufreq.c
>> +++ b/drivers/cpufreq/cppc_cpufreq.c
>> @@ -831,72 +831,63 @@ static ssize_t store_auto_select(struct cpufreq_policy *policy,
>>        return count;
>>   }
>>
>> -static ssize_t show_auto_act_window(struct cpufreq_policy *policy, char *buf)
>> +static ssize_t cppc_cpufreq_sysfs_show_u64(unsigned int cpu,
>> +                                        int (*get_func)(int, u64 *),
>> +                                        char *buf)
>>   {
>>        u64 val;
>> -     int ret;
>> -
>> -     ret = cppc_get_auto_act_window(policy->cpu, &val);
>> +     int ret = get_func((int)cpu, &val);
>>
>> -     /* show "<unsupported>" when this register is not supported by cpc */
>>        if (ret == -EOPNOTSUPP)
>>                return sysfs_emit(buf, "<unsupported>\n");
>> -
>>        if (ret)
>>                return ret;
>>
>>        return sysfs_emit(buf, "%llu\n", val);
>>   }
>>
>> -static ssize_t store_auto_act_window(struct cpufreq_policy *policy,
>> -                                  const char *buf, size_t count)
>> +static ssize_t cppc_cpufreq_sysfs_store_u64(unsigned int cpu,
>> +                                         int (*set_func)(int, u64),
>> +                                         const char *buf, size_t count)
>>   {
>> -     u64 usec;
>> +     u64 val;
>>        int ret;
>>
>> -     ret = kstrtou64(buf, 0, &usec);
>> +     ret = kstrtou64(buf, 0, &val);
>>        if (ret)
>>                return ret;
>>
>> -     ret = cppc_set_auto_act_window(policy->cpu, usec);
>> -     if (ret)
>> -             return ret;
>> +     ret = set_func((int)cpu, val);
>>
>> -     return count;
>> +     return ret ? ret : count;
>>   }
>>
>> -static ssize_t show_energy_performance_preference_val(struct cpufreq_policy *policy, char *buf)
>> +static ssize_t show_auto_act_window(struct cpufreq_policy *policy, char *buf)
>>   {
>> -     u64 val;
>> -     int ret;
>> -
>> -     ret = cppc_get_epp_perf(policy->cpu, &val);
>> -
>> -     /* show "<unsupported>" when this register is not supported by cpc */
>> -     if (ret == -EOPNOTSUPP)
>> -             return sysfs_emit(buf, "<unsupported>\n");
>> -
>> -     if (ret)
>> -             return ret;
>> -
>> -     return sysfs_emit(buf, "%llu\n", val);
>> +     return cppc_cpufreq_sysfs_show_u64(policy->cpu,
>> +                                        cppc_get_auto_act_window, buf);
>>   }
>>
>> -static ssize_t store_energy_performance_preference_val(struct cpufreq_policy *policy,
>> -                                                    const char *buf, size_t count)
>> +static ssize_t store_auto_act_window(struct cpufreq_policy *policy,
>> +                                  const char *buf, size_t count)
>>   {
>> -     u64 val;
>> -     int ret;
>> -
>> -     ret = kstrtou64(buf, 0, &val);
>> -     if (ret)
>> -             return ret;
>> +     return cppc_cpufreq_sysfs_store_u64(policy->cpu,
>> +                                         cppc_set_auto_act_window,
>> +                                         buf, count);
>> +}
>>
>> -     ret = cppc_set_epp(policy->cpu, val);
>> -     if (ret)
>> -             return ret;
>> +static ssize_t
>> +show_energy_performance_preference_val(struct cpufreq_policy *policy, char *buf)
>> +{
>> +     return cppc_cpufreq_sysfs_show_u64(policy->cpu, cppc_get_epp_perf, buf);
>> +}
>>
>> -     return count;
>> +static ssize_t
>> +store_energy_performance_preference_val(struct cpufreq_policy *policy,
>> +                                     const char *buf, size_t count)
>> +{
>> +     return cppc_cpufreq_sysfs_store_u64(policy->cpu, cppc_set_epp,
>> +                                         buf, count);
>>   }
>>
>>   cpufreq_freq_attr_ro(freqdomain_cpus);

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