Add generic helper functions for u64 sysfs attributes that follow the
common pattern of calling CPPC get/set APIs:
- cppc_cpufreq_sysfs_show_u64(): reads value and handles -EOPNOTSUPP
- cppc_cpufreq_sysfs_store_u64(): parses input and calls set function
Add CPPC_CPUFREQ_ATTR_RW_U64() macro to generate show/store functions
using these helpers, reducing boilerplate for simple attributes.
Convert auto_act_window and energy_performance_preference_val to use
the new macro.
No functional changes.
Signed-off-by: Sumit Gupta <sumitg@nvidia.com>
---
drivers/cpufreq/cppc_cpufreq.c | 69 ++++++++++++----------------------
1 file changed, 25 insertions(+), 44 deletions(-)
diff --git a/drivers/cpufreq/cppc_cpufreq.c b/drivers/cpufreq/cppc_cpufreq.c
index 36e8a75a37f1..c95dcd7719c3 100644
--- a/drivers/cpufreq/cppc_cpufreq.c
+++ b/drivers/cpufreq/cppc_cpufreq.c
@@ -863,73 +863,54 @@ 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)
-{
- 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);
+#define CPPC_CPUFREQ_ATTR_RW_U64(_name, _get_func, _set_func) \
+static ssize_t show_##_name(struct cpufreq_policy *policy, char *buf) \
+{ \
+ return cppc_cpufreq_sysfs_show_u64(policy->cpu, _get_func, buf);\
+} \
+static ssize_t store_##_name(struct cpufreq_policy *policy, \
+ const char *buf, size_t count) \
+{ \
+ return cppc_cpufreq_sysfs_store_u64(policy->cpu, _set_func, \
+ buf, count); \
}
-static ssize_t store_energy_performance_preference_val(struct cpufreq_policy *policy,
- const char *buf, size_t count)
-{
- u64 val;
- int ret;
+CPPC_CPUFREQ_ATTR_RW_U64(auto_act_window, cppc_get_auto_act_window,
+ cppc_set_auto_act_window)
- ret = kstrtou64(buf, 0, &val);
- if (ret)
- return ret;
-
- ret = cppc_set_epp(policy->cpu, val);
- if (ret)
- return ret;
-
- return count;
-}
+CPPC_CPUFREQ_ATTR_RW_U64(energy_performance_preference_val,
+ cppc_get_epp_perf, cppc_set_epp)
cpufreq_freq_attr_ro(freqdomain_cpus);
cpufreq_freq_attr_rw(auto_select);
--
2.34.1On Tue, Jan 20, 2026 at 3:57 PM Sumit Gupta <sumitg@nvidia.com> wrote:
>
> Add generic helper functions for u64 sysfs attributes that follow the
> common pattern of calling CPPC get/set APIs:
> - cppc_cpufreq_sysfs_show_u64(): reads value and handles -EOPNOTSUPP
> - cppc_cpufreq_sysfs_store_u64(): parses input and calls set function
>
> Add CPPC_CPUFREQ_ATTR_RW_U64() macro to generate show/store functions
> using these helpers, reducing boilerplate for simple attributes.
>
> Convert auto_act_window and energy_performance_preference_val to use
> the new macro.
>
> No functional changes.
>
> Signed-off-by: Sumit Gupta <sumitg@nvidia.com>
> ---
> drivers/cpufreq/cppc_cpufreq.c | 69 ++++++++++++----------------------
> 1 file changed, 25 insertions(+), 44 deletions(-)
>
> diff --git a/drivers/cpufreq/cppc_cpufreq.c b/drivers/cpufreq/cppc_cpufreq.c
> index 36e8a75a37f1..c95dcd7719c3 100644
> --- a/drivers/cpufreq/cppc_cpufreq.c
> +++ b/drivers/cpufreq/cppc_cpufreq.c
> @@ -863,73 +863,54 @@ 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)
> -{
> - 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);
> +#define CPPC_CPUFREQ_ATTR_RW_U64(_name, _get_func, _set_func) \
> +static ssize_t show_##_name(struct cpufreq_policy *policy, char *buf) \
> +{ \
> + return cppc_cpufreq_sysfs_show_u64(policy->cpu, _get_func, buf);\
> +} \
> +static ssize_t store_##_name(struct cpufreq_policy *policy, \
> + const char *buf, size_t count) \
> +{ \
> + return cppc_cpufreq_sysfs_store_u64(policy->cpu, _set_func, \
> + buf, count); \
> }
>
> -static ssize_t store_energy_performance_preference_val(struct cpufreq_policy *policy,
> - const char *buf, size_t count)
> -{
> - u64 val;
> - int ret;
> +CPPC_CPUFREQ_ATTR_RW_U64(auto_act_window, cppc_get_auto_act_window,
> + cppc_set_auto_act_window)
>
> - ret = kstrtou64(buf, 0, &val);
> - if (ret)
> - return ret;
> -
> - ret = cppc_set_epp(policy->cpu, val);
> - if (ret)
> - return ret;
> -
> - return count;
> -}
> +CPPC_CPUFREQ_ATTR_RW_U64(energy_performance_preference_val,
> + cppc_get_epp_perf, cppc_set_epp)
>
> cpufreq_freq_attr_ro(freqdomain_cpus);
> cpufreq_freq_attr_rw(auto_select);
> --
It looks like this patch could be applied independently of the other
patches in the series.
Do you want me to do so?
On 27/01/26 21:54, Rafael J. Wysocki wrote:
> External email: Use caution opening links or attachments
>
>
> On Tue, Jan 20, 2026 at 3:57 PM Sumit Gupta <sumitg@nvidia.com> wrote:
>> Add generic helper functions for u64 sysfs attributes that follow the
>> common pattern of calling CPPC get/set APIs:
>> - cppc_cpufreq_sysfs_show_u64(): reads value and handles -EOPNOTSUPP
>> - cppc_cpufreq_sysfs_store_u64(): parses input and calls set function
>>
>> Add CPPC_CPUFREQ_ATTR_RW_U64() macro to generate show/store functions
>> using these helpers, reducing boilerplate for simple attributes.
>>
>> Convert auto_act_window and energy_performance_preference_val to use
>> the new macro.
>>
>> No functional changes.
>>
>> Signed-off-by: Sumit Gupta <sumitg@nvidia.com>
>> ---
>> drivers/cpufreq/cppc_cpufreq.c | 69 ++++++++++++----------------------
>> 1 file changed, 25 insertions(+), 44 deletions(-)
>>
>> diff --git a/drivers/cpufreq/cppc_cpufreq.c b/drivers/cpufreq/cppc_cpufreq.c
>> index 36e8a75a37f1..c95dcd7719c3 100644
>> --- a/drivers/cpufreq/cppc_cpufreq.c
>> +++ b/drivers/cpufreq/cppc_cpufreq.c
>> @@ -863,73 +863,54 @@ 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)
>> -{
>> - 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);
>> +#define CPPC_CPUFREQ_ATTR_RW_U64(_name, _get_func, _set_func) \
>> +static ssize_t show_##_name(struct cpufreq_policy *policy, char *buf) \
>> +{ \
>> + return cppc_cpufreq_sysfs_show_u64(policy->cpu, _get_func, buf);\
>> +} \
>> +static ssize_t store_##_name(struct cpufreq_policy *policy, \
>> + const char *buf, size_t count) \
>> +{ \
>> + return cppc_cpufreq_sysfs_store_u64(policy->cpu, _set_func, \
>> + buf, count); \
>> }
>>
>> -static ssize_t store_energy_performance_preference_val(struct cpufreq_policy *policy,
>> - const char *buf, size_t count)
>> -{
>> - u64 val;
>> - int ret;
>> +CPPC_CPUFREQ_ATTR_RW_U64(auto_act_window, cppc_get_auto_act_window,
>> + cppc_set_auto_act_window)
>>
>> - ret = kstrtou64(buf, 0, &val);
>> - if (ret)
>> - return ret;
>> -
>> - ret = cppc_set_epp(policy->cpu, val);
>> - if (ret)
>> - return ret;
>> -
>> - return count;
>> -}
>> +CPPC_CPUFREQ_ATTR_RW_U64(energy_performance_preference_val,
>> + cppc_get_epp_perf, cppc_set_epp)
>>
>> cpufreq_freq_attr_ro(freqdomain_cpus);
>> cpufreq_freq_attr_rw(auto_select);
>> --
> It looks like this patch could be applied independently of the other
> patches in the series.
>
> Do you want me to do so?
Yes, this patch is independent and can be applied.
Thank you,
Sumit Gupta
On Tue, Jan 27, 2026 at 8:01 PM Sumit Gupta <sumitg@nvidia.com> wrote:
>
>
> On 27/01/26 21:54, Rafael J. Wysocki wrote:
> > External email: Use caution opening links or attachments
> >
> >
> > On Tue, Jan 20, 2026 at 3:57 PM Sumit Gupta <sumitg@nvidia.com> wrote:
> >> Add generic helper functions for u64 sysfs attributes that follow the
> >> common pattern of calling CPPC get/set APIs:
> >> - cppc_cpufreq_sysfs_show_u64(): reads value and handles -EOPNOTSUPP
> >> - cppc_cpufreq_sysfs_store_u64(): parses input and calls set function
> >>
> >> Add CPPC_CPUFREQ_ATTR_RW_U64() macro to generate show/store functions
> >> using these helpers, reducing boilerplate for simple attributes.
> >>
> >> Convert auto_act_window and energy_performance_preference_val to use
> >> the new macro.
> >>
> >> No functional changes.
> >>
> >> Signed-off-by: Sumit Gupta <sumitg@nvidia.com>
> >> ---
> >> drivers/cpufreq/cppc_cpufreq.c | 69 ++++++++++++----------------------
> >> 1 file changed, 25 insertions(+), 44 deletions(-)
> >>
> >> diff --git a/drivers/cpufreq/cppc_cpufreq.c b/drivers/cpufreq/cppc_cpufreq.c
> >> index 36e8a75a37f1..c95dcd7719c3 100644
> >> --- a/drivers/cpufreq/cppc_cpufreq.c
> >> +++ b/drivers/cpufreq/cppc_cpufreq.c
> >> @@ -863,73 +863,54 @@ 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)
> >> -{
> >> - 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);
> >> +#define CPPC_CPUFREQ_ATTR_RW_U64(_name, _get_func, _set_func) \
> >> +static ssize_t show_##_name(struct cpufreq_policy *policy, char *buf) \
> >> +{ \
> >> + return cppc_cpufreq_sysfs_show_u64(policy->cpu, _get_func, buf);\
> >> +} \
> >> +static ssize_t store_##_name(struct cpufreq_policy *policy, \
> >> + const char *buf, size_t count) \
> >> +{ \
> >> + return cppc_cpufreq_sysfs_store_u64(policy->cpu, _set_func, \
> >> + buf, count); \
> >> }
> >>
> >> -static ssize_t store_energy_performance_preference_val(struct cpufreq_policy *policy,
> >> - const char *buf, size_t count)
> >> -{
> >> - u64 val;
> >> - int ret;
> >> +CPPC_CPUFREQ_ATTR_RW_U64(auto_act_window, cppc_get_auto_act_window,
> >> + cppc_set_auto_act_window)
> >>
> >> - ret = kstrtou64(buf, 0, &val);
> >> - if (ret)
> >> - return ret;
> >> -
> >> - ret = cppc_set_epp(policy->cpu, val);
> >> - if (ret)
> >> - return ret;
> >> -
> >> - return count;
> >> -}
> >> +CPPC_CPUFREQ_ATTR_RW_U64(energy_performance_preference_val,
> >> + cppc_get_epp_perf, cppc_set_epp)
> >>
> >> cpufreq_freq_attr_ro(freqdomain_cpus);
> >> cpufreq_freq_attr_rw(auto_select);
> >> --
> > It looks like this patch could be applied independently of the other
> > patches in the series.
> >
> > Do you want me to do so?
>
> Yes, this patch is independent and can be applied.
Applied as 6.20 material, thanks!
On 2026/1/20 22:56, Sumit Gupta wrote:
> Add generic helper functions for u64 sysfs attributes that follow the
> common pattern of calling CPPC get/set APIs:
> - cppc_cpufreq_sysfs_show_u64(): reads value and handles -EOPNOTSUPP
> - cppc_cpufreq_sysfs_store_u64(): parses input and calls set function
>
> Add CPPC_CPUFREQ_ATTR_RW_U64() macro to generate show/store functions
> using these helpers, reducing boilerplate for simple attributes.
>
> Convert auto_act_window and energy_performance_preference_val to use
> the new macro.
>
> No functional changes.
>
> Signed-off-by: Sumit Gupta <sumitg@nvidia.com>
> ---
> drivers/cpufreq/cppc_cpufreq.c | 69 ++++++++++++----------------------
> 1 file changed, 25 insertions(+), 44 deletions(-)
>
> diff --git a/drivers/cpufreq/cppc_cpufreq.c b/drivers/cpufreq/cppc_cpufreq.c
> index 36e8a75a37f1..c95dcd7719c3 100644
> --- a/drivers/cpufreq/cppc_cpufreq.c
> +++ b/drivers/cpufreq/cppc_cpufreq.c
> @@ -863,73 +863,54 @@ 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");
> -
I think it is better to keep this blank line. Apart from this
Reviewed-by: Lifeng Zheng <zhenglifeng1@huawei.com>
> 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)
> -{
> - 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);
> +#define CPPC_CPUFREQ_ATTR_RW_U64(_name, _get_func, _set_func) \
> +static ssize_t show_##_name(struct cpufreq_policy *policy, char *buf) \
> +{ \
> + return cppc_cpufreq_sysfs_show_u64(policy->cpu, _get_func, buf);\
> +} \
> +static ssize_t store_##_name(struct cpufreq_policy *policy, \
> + const char *buf, size_t count) \
> +{ \
> + return cppc_cpufreq_sysfs_store_u64(policy->cpu, _set_func, \
> + buf, count); \
> }
>
> -static ssize_t store_energy_performance_preference_val(struct cpufreq_policy *policy,
> - const char *buf, size_t count)
> -{
> - u64 val;
> - int ret;
> +CPPC_CPUFREQ_ATTR_RW_U64(auto_act_window, cppc_get_auto_act_window,
> + cppc_set_auto_act_window)
>
> - ret = kstrtou64(buf, 0, &val);
> - if (ret)
> - return ret;
> -
> - ret = cppc_set_epp(policy->cpu, val);
> - if (ret)
> - return ret;
> -
> - return count;
> -}
> +CPPC_CPUFREQ_ATTR_RW_U64(energy_performance_preference_val,
> + cppc_get_epp_perf, cppc_set_epp)
>
> cpufreq_freq_attr_ro(freqdomain_cpus);
> cpufreq_freq_attr_rw(auto_select);
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