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[PATCH v2 2/3] ACPI: processor: Remove unused empty function definition for processor_idle.c

Huisong Li posted 3 patches 4 days, 13 hours ago
[PATCH v2 2/3] ACPI: processor: Remove unused empty function definition for processor_idle.c
Posted by Huisong Li 4 days, 13 hours ago 
If CONFIG_ACPI_PROCESSOR=n and CONFIG_ACPI_PROCESSOR_IDLE=n, we may encounter
some warnings about function defined but not used.
All external functions of processor_idle.c are just used in processor_driver.c.
And if CONFIG_ACPI_PROCESSOR is selected and CONFIG_ACPI_PROCESSOR_IDLE also
be selected automatically. So remove these empty function definitions.

Signed-off-by: Huisong Li <lihuisong@huawei.com>
---
 include/acpi/processor.h | 22 +---------------------
 1 file changed, 1 insertion(+), 21 deletions(-)

diff --git a/include/acpi/processor.h b/include/acpi/processor.h
index ff864c1cee3a..d6a87dc42a9a 100644
--- a/include/acpi/processor.h
+++ b/include/acpi/processor.h
@@ -417,34 +417,14 @@ static inline void acpi_processor_throttling_init(void) {}
 #endif	/* CONFIG_ACPI_CPU_FREQ_PSS */
 
 /* in processor_idle.c */
-extern struct cpuidle_driver acpi_idle_driver;
 #ifdef CONFIG_ACPI_PROCESSOR_IDLE
+extern struct cpuidle_driver acpi_idle_driver;
 int acpi_processor_power_init(struct acpi_processor *pr);
 int acpi_processor_power_exit(struct acpi_processor *pr);
 int acpi_processor_power_state_has_changed(struct acpi_processor *pr);
 int acpi_processor_hotplug(struct acpi_processor *pr);
 void acpi_processor_register_idle_driver(void);
 void acpi_processor_unregister_idle_driver(void);
-#else
-static inline int acpi_processor_power_init(struct acpi_processor *pr)
-{
-	return -ENODEV;
-}
-
-static inline int acpi_processor_power_exit(struct acpi_processor *pr)
-{
-	return -ENODEV;
-}
-
-static inline int acpi_processor_power_state_has_changed(struct acpi_processor *pr)
-{
-	return -ENODEV;
-}
-
-static inline int acpi_processor_hotplug(struct acpi_processor *pr)
-{
-	return -ENODEV;
-}
 #endif /* CONFIG_ACPI_PROCESSOR_IDLE */
 
 /* in processor_thermal.c */
-- 
2.33.0
Re: [PATCH v2 2/3] ACPI: processor: Remove unused empty function definition for processor_idle.c
Posted by Rafael J. Wysocki 4 days, 1 hour ago 
On Fri, Sep 5, 2025 at 10:19 AM Huisong Li <lihuisong@huawei.com> wrote:
>
> If CONFIG_ACPI_PROCESSOR=n and CONFIG_ACPI_PROCESSOR_IDLE=n, we may encounter
> some warnings about function defined but not used.
> All external functions of processor_idle.c are just used in processor_driver.c.
> And if CONFIG_ACPI_PROCESSOR is selected and CONFIG_ACPI_PROCESSOR_IDLE also
> be selected automatically. So remove these empty function definitions.
>
> Signed-off-by: Huisong Li <lihuisong@huawei.com>
> ---
>  include/acpi/processor.h | 22 +---------------------
>  1 file changed, 1 insertion(+), 21 deletions(-)
>
> diff --git a/include/acpi/processor.h b/include/acpi/processor.h
> index ff864c1cee3a..d6a87dc42a9a 100644
> --- a/include/acpi/processor.h
> +++ b/include/acpi/processor.h
> @@ -417,34 +417,14 @@ static inline void acpi_processor_throttling_init(void) {}
>  #endif /* CONFIG_ACPI_CPU_FREQ_PSS */
>
>  /* in processor_idle.c */
> -extern struct cpuidle_driver acpi_idle_driver;
>  #ifdef CONFIG_ACPI_PROCESSOR_IDLE
> +extern struct cpuidle_driver acpi_idle_driver;

The changes above don't belong to this patch IMV or at least I don't
see why they belong to it.

>  int acpi_processor_power_init(struct acpi_processor *pr);
>  int acpi_processor_power_exit(struct acpi_processor *pr);
>  int acpi_processor_power_state_has_changed(struct acpi_processor *pr);
>  int acpi_processor_hotplug(struct acpi_processor *pr);
>  void acpi_processor_register_idle_driver(void);
>  void acpi_processor_unregister_idle_driver(void);
> -#else
> -static inline int acpi_processor_power_init(struct acpi_processor *pr)
> -{
> -       return -ENODEV;
> -}
> -
> -static inline int acpi_processor_power_exit(struct acpi_processor *pr)
> -{
> -       return -ENODEV;
> -}
> -
> -static inline int acpi_processor_power_state_has_changed(struct acpi_processor *pr)
> -{
> -       return -ENODEV;
> -}
> -
> -static inline int acpi_processor_hotplug(struct acpi_processor *pr)
> -{
> -       return -ENODEV;
> -}
>  #endif /* CONFIG_ACPI_PROCESSOR_IDLE */
>
>  /* in processor_thermal.c */
> --
Re: [PATCH v2 2/3] ACPI: processor: Remove unused empty function definition for processor_idle.c
Posted by lihuisong (C) 1 day, 14 hours ago 
Hi Rafael,

Thanks for you fast reply.


在 2025/9/6 3:50, Rafael J. Wysocki 写道:
> On Fri, Sep 5, 2025 at 10:19 AM Huisong Li <lihuisong@huawei.com> wrote:
>> If CONFIG_ACPI_PROCESSOR=n and CONFIG_ACPI_PROCESSOR_IDLE=n, we may encounter
>> some warnings about function defined but not used.
>> All external functions of processor_idle.c are just used in processor_driver.c.
>> And if CONFIG_ACPI_PROCESSOR is selected and CONFIG_ACPI_PROCESSOR_IDLE also
>> be selected automatically. So remove these empty function definitions.
>>
>> Signed-off-by: Huisong Li <lihuisong@huawei.com>
>> ---
>>   include/acpi/processor.h | 22 +---------------------
>>   1 file changed, 1 insertion(+), 21 deletions(-)
>>
>> diff --git a/include/acpi/processor.h b/include/acpi/processor.h
>> index ff864c1cee3a..d6a87dc42a9a 100644
>> --- a/include/acpi/processor.h
>> +++ b/include/acpi/processor.h
>> @@ -417,34 +417,14 @@ static inline void acpi_processor_throttling_init(void) {}
>>   #endif /* CONFIG_ACPI_CPU_FREQ_PSS */
>>
>>   /* in processor_idle.c */
>> -extern struct cpuidle_driver acpi_idle_driver;
>>   #ifdef CONFIG_ACPI_PROCESSOR_IDLE
>> +extern struct cpuidle_driver acpi_idle_driver;
> The changes above don't belong to this patch IMV or at least I don't
> see why they belong to it.

Yes, I just do it by the way.

Ok, I will fix it like the folloing way in a separate patch.

How do you think?

-->

diff --git a/drivers/acpi/processor_driver.c 
b/drivers/acpi/processor_driver.c
index bc9f58a02c1d..5d824435b26b 100644
--- a/drivers/acpi/processor_driver.c
+++ b/drivers/acpi/processor_driver.c
@@ -166,8 +166,7 @@ static int __acpi_processor_start(struct acpi_device 
*device)
         if (result && !IS_ENABLED(CONFIG_ACPI_CPU_FREQ_PSS))
                 dev_dbg(&device->dev, "CPPC data invalid or not 
present\n");

-       if (!cpuidle_get_driver() || cpuidle_get_driver() == 
&acpi_idle_driver)
-               acpi_processor_power_init(pr);
+       acpi_processor_power_init(pr);

         acpi_pss_perf_init(pr);

diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c
index 5dacf41d7cc0..967fb13f38fa 100644
--- a/drivers/acpi/processor_idle.c
+++ b/drivers/acpi/processor_idle.c
@@ -1404,6 +1404,11 @@ int acpi_processor_power_init(struct 
acpi_processor *pr)
  {
         int retval;
         struct cpuidle_device *dev;
+       struct cpuidle_driver *drv;
+
+       drv = cpuidle_get_driver();
+       if (drv && drv != &acpi_idle_driver)
+               return 0;

         if (disabled_by_idle_boot_param())
                 return 0;
diff --git a/include/acpi/processor.h b/include/acpi/processor.h
index ff864c1cee3a..dcc500bdd5cd 100644
--- a/include/acpi/processor.h
+++ b/include/acpi/processor.h
@@ -417,7 +417,6 @@ static inline void 
acpi_processor_throttling_init(void) {}
  #endif /* CONFIG_ACPI_CPU_FREQ_PSS */

  /* in processor_idle.c */
-extern struct cpuidle_driver acpi_idle_driver;
  #ifdef CONFIG_ACPI_PROCESSOR_IDLE
  int acpi_processor_power_init(struct acpi_processor *pr);
  int acpi_processor_power_exit(struct acpi_processor *pr);

>
>>   int acpi_processor_power_init(struct acpi_processor *pr);
>>   int acpi_processor_power_exit(struct acpi_processor *pr);
>>   int acpi_processor_power_state_has_changed(struct acpi_processor *pr);
>>   int acpi_processor_hotplug(struct acpi_processor *pr);
<...>

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