[PATCH] devfreq_cooling: pass a pointer to devfreq in the power model callbacks

[PATCH] devfreq_cooling: pass a pointer to devfreq in the power model callbacks

[Javi Merino]

It's useful for a driver to know which device it's referring to when
calculating its dynamic or static power.  Pass a pointer to devfreq
in the callbacks to let the driver know which device it refers to.

This is similar to what we do for the cpu cooling device power model.
For that, we pass a cpumask of the affected cpus.

Cc: Zhang Rui <rui.zhang@intel.com>
Cc: Eduardo Valentin <edubezval@gmail.com>
Signed-off-by: Javi Merino <javi.merino@arm.com>
---
 drivers/thermal/devfreq_cooling.c | 5 +++--
 include/linux/devfreq_cooling.h   | 6 ++++--
 2 files changed, 7 insertions(+), 4 deletions(-)

diff --git a/drivers/thermal/devfreq_cooling.c b/drivers/thermal/devfreq_cooling.c
index 01f0015f80dc..c549d83a0c7d 100644
--- a/drivers/thermal/devfreq_cooling.c
+++ b/drivers/thermal/devfreq_cooling.c
@@ -238,7 +238,7 @@ get_static_power(struct devfreq_cooling_device *dfc, unsigned long freq)
 		return 0;
 	}
 
-	return dfc->power_ops->get_static_power(voltage);
+	return dfc->power_ops->get_static_power(df, voltage);
 }
 
 /**
@@ -262,7 +262,8 @@ get_dynamic_power(struct devfreq_cooling_device *dfc, unsigned long freq,
 	struct devfreq_cooling_power *dfc_power = dfc->power_ops;
 
 	if (dfc_power->get_dynamic_power)
-		return dfc_power->get_dynamic_power(freq, voltage);
+		return dfc_power->get_dynamic_power(dfc->devfreq, freq,
+						    voltage);
 
 	freq_mhz = freq / 1000000;
 	power = (u64)dfc_power->dyn_power_coeff * freq_mhz * voltage * voltage;
diff --git a/include/linux/devfreq_cooling.h b/include/linux/devfreq_cooling.h
index 7adf6cc4b305..959714e93e5b 100644
--- a/include/linux/devfreq_cooling.h
+++ b/include/linux/devfreq_cooling.h
@@ -37,8 +37,10 @@
  *			@dyn_power_coeff * frequency * voltage^2
  */
 struct devfreq_cooling_power {
-	unsigned long (*get_static_power)(unsigned long voltage);
-	unsigned long (*get_dynamic_power)(unsigned long freq,
+	unsigned long (*get_static_power)(struct devfreq *devfreq,
+					  unsigned long voltage);
+	unsigned long (*get_dynamic_power)(struct devfreq *devfreq,
+					   unsigned long freq,
 					   unsigned long voltage);
 	unsigned long dyn_power_coeff;
 };
-- 
1.9.1

Re: [PATCH] devfreq_cooling: pass a pointer to devfreq in the power model callbacks

[Punit Agrawal]

Javi Merino <javi.merino@arm.com> writes:

> It's useful for a driver to know which device it's referring to when
> calculating its dynamic or static power.  Pass a pointer to devfreq
> in the callbacks to let the driver know which device it refers to.
>
> This is similar to what we do for the cpu cooling device power model.
> For that, we pass a cpumask of the affected cpus.
>
> Cc: Zhang Rui <rui.zhang@intel.com>
> Cc: Eduardo Valentin <edubezval@gmail.com>
> Signed-off-by: Javi Merino <javi.merino@arm.com>
> ---
>  drivers/thermal/devfreq_cooling.c | 5 +++--
>  include/linux/devfreq_cooling.h   | 6 ++++--
>  2 files changed, 7 insertions(+), 4 deletions(-)
>

Reviewed-by: Punit Agrawal <punit.agrawal@arm.com>

Thanks!

Re: [PATCH] devfreq_cooling: pass a pointer to devfreq in the power model callbacks

[Lukasz Luba]

Hi,

On 20/06/16 18:36, Javi Merino wrote:
> Eduardo, Rui,
>
> On Fri, Jun 03, 2016 at 10:25:31AM +0100, Javi Merino wrote:
>> When the devfreq cooling device was designed, it was an oversight not to
>> pass a pointer to the struct devfreq as the first parameters of the
>> callbacks.  The design patterns of the kernel suggest it for a good
>> reason.
>>
>> By passing a pointer to struct devfreq, the driver can register one
>> function that works with multiple devices.  With the current
>> implementation, a driver that can work with multiple devices has to
>> create multiple copies of the same function with different parameters so
>> that each devfreq_cooling_device can use the appropriate one.  By
>> passing a pointer to struct devfreq, the driver can identify which
>> device it's referring to.
>>
>> Cc: Zhang Rui <rui.zhang@intel.com>
>> Cc: Eduardo Valentin <edubezval@gmail.com>
>> Reviewed-by: Punit Agrawal <punit.agrawal@arm.com>
>> Signed-off-by: Javi Merino <javi.merino@arm.com>
>> ---
>>   drivers/thermal/devfreq_cooling.c | 5 +++--
>>   include/linux/devfreq_cooling.h   | 6 ++++--
>>   2 files changed, 7 insertions(+), 4 deletions(-)
>>
>> diff --git a/drivers/thermal/devfreq_cooling.c b/drivers/thermal/devfreq_cooling.c
>> index 01f0015f80dc..c549d83a0c7d 100644
>> --- a/drivers/thermal/devfreq_cooling.c
>> +++ b/drivers/thermal/devfreq_cooling.c
>> @@ -238,7 +238,7 @@ get_static_power(struct devfreq_cooling_device *dfc, unsigned long freq)
>>   		return 0;
>>   	}
>>
>> -	return dfc->power_ops->get_static_power(voltage);
>> +	return dfc->power_ops->get_static_power(df, voltage);
>>   }
>>
>>   /**
>> @@ -262,7 +262,8 @@ get_dynamic_power(struct devfreq_cooling_device *dfc, unsigned long freq,
>>   	struct devfreq_cooling_power *dfc_power = dfc->power_ops;
>>
>>   	if (dfc_power->get_dynamic_power)
>> -		return dfc_power->get_dynamic_power(freq, voltage);
>> +		return dfc_power->get_dynamic_power(dfc->devfreq, freq,
>> +						    voltage);
>>
>>   	freq_mhz = freq / 1000000;
>>   	power = (u64)dfc_power->dyn_power_coeff * freq_mhz * voltage * voltage;
>> diff --git a/include/linux/devfreq_cooling.h b/include/linux/devfreq_cooling.h
>> index 7adf6cc4b305..959714e93e5b 100644
>> --- a/include/linux/devfreq_cooling.h
>> +++ b/include/linux/devfreq_cooling.h
>> @@ -37,8 +37,10 @@
>>    *			@dyn_power_coeff * frequency * voltage^2
>>    */
>>   struct devfreq_cooling_power {
>> -	unsigned long (*get_static_power)(unsigned long voltage);
>> -	unsigned long (*get_dynamic_power)(unsigned long freq,
>> +	unsigned long (*get_static_power)(struct devfreq *devfreq,
>> +					  unsigned long voltage);
>> +	unsigned long (*get_dynamic_power)(struct devfreq *devfreq,
>> +					   unsigned long freq,
>>   					   unsigned long voltage);
>>   	unsigned long dyn_power_coeff;
>>   };
>
> If there are no objections, can you pick this for the next merge
> window?
>
> Thanks,
> Javi
>
This is very useful code, please pick it.

Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>

Regards,
Lukasz

Re: [PATCH] devfreq_cooling: pass a pointer to devfreq in the power model callbacks

[Javi Merino]

Eduardo, Rui,

On Fri, Jun 03, 2016 at 10:25:31AM +0100, Javi Merino wrote:
> When the devfreq cooling device was designed, it was an oversight not to
> pass a pointer to the struct devfreq as the first parameters of the
> callbacks.  The design patterns of the kernel suggest it for a good
> reason.
> 
> By passing a pointer to struct devfreq, the driver can register one
> function that works with multiple devices.  With the current
> implementation, a driver that can work with multiple devices has to
> create multiple copies of the same function with different parameters so
> that each devfreq_cooling_device can use the appropriate one.  By
> passing a pointer to struct devfreq, the driver can identify which
> device it's referring to.
> 
> Cc: Zhang Rui <rui.zhang@intel.com>
> Cc: Eduardo Valentin <edubezval@gmail.com>
> Reviewed-by: Punit Agrawal <punit.agrawal@arm.com>
> Signed-off-by: Javi Merino <javi.merino@arm.com>
> ---
>  drivers/thermal/devfreq_cooling.c | 5 +++--
>  include/linux/devfreq_cooling.h   | 6 ++++--
>  2 files changed, 7 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/thermal/devfreq_cooling.c b/drivers/thermal/devfreq_cooling.c
> index 01f0015f80dc..c549d83a0c7d 100644
> --- a/drivers/thermal/devfreq_cooling.c
> +++ b/drivers/thermal/devfreq_cooling.c
> @@ -238,7 +238,7 @@ get_static_power(struct devfreq_cooling_device *dfc, unsigned long freq)
>  		return 0;
>  	}
>  
> -	return dfc->power_ops->get_static_power(voltage);
> +	return dfc->power_ops->get_static_power(df, voltage);
>  }
>  
>  /**
> @@ -262,7 +262,8 @@ get_dynamic_power(struct devfreq_cooling_device *dfc, unsigned long freq,
>  	struct devfreq_cooling_power *dfc_power = dfc->power_ops;
>  
>  	if (dfc_power->get_dynamic_power)
> -		return dfc_power->get_dynamic_power(freq, voltage);
> +		return dfc_power->get_dynamic_power(dfc->devfreq, freq,
> +						    voltage);
>  
>  	freq_mhz = freq / 1000000;
>  	power = (u64)dfc_power->dyn_power_coeff * freq_mhz * voltage * voltage;
> diff --git a/include/linux/devfreq_cooling.h b/include/linux/devfreq_cooling.h
> index 7adf6cc4b305..959714e93e5b 100644
> --- a/include/linux/devfreq_cooling.h
> +++ b/include/linux/devfreq_cooling.h
> @@ -37,8 +37,10 @@
>   *			@dyn_power_coeff * frequency * voltage^2
>   */
>  struct devfreq_cooling_power {
> -	unsigned long (*get_static_power)(unsigned long voltage);
> -	unsigned long (*get_dynamic_power)(unsigned long freq,
> +	unsigned long (*get_static_power)(struct devfreq *devfreq,
> +					  unsigned long voltage);
> +	unsigned long (*get_dynamic_power)(struct devfreq *devfreq,
> +					   unsigned long freq,
>  					   unsigned long voltage);
>  	unsigned long dyn_power_coeff;
>  };

If there are no objections, can you pick this for the next merge
window?

Thanks,
Javi

[PATCH] devfreq_cooling: pass a pointer to devfreq in the power model callbacks

[Javi Merino]

When the devfreq cooling device was designed, it was an oversight not to
pass a pointer to the struct devfreq as the first parameters of the
callbacks.  The design patterns of the kernel suggest it for a good
reason.

By passing a pointer to struct devfreq, the driver can register one
function that works with multiple devices.  With the current
implementation, a driver that can work with multiple devices has to
create multiple copies of the same function with different parameters so
that each devfreq_cooling_device can use the appropriate one.  By
passing a pointer to struct devfreq, the driver can identify which
device it's referring to.

Cc: Zhang Rui <rui.zhang@intel.com>
Cc: Eduardo Valentin <edubezval@gmail.com>
Reviewed-by: Punit Agrawal <punit.agrawal@arm.com>
Signed-off-by: Javi Merino <javi.merino@arm.com>
---
 drivers/thermal/devfreq_cooling.c | 5 +++--
 include/linux/devfreq_cooling.h   | 6 ++++--
 2 files changed, 7 insertions(+), 4 deletions(-)

diff --git a/drivers/thermal/devfreq_cooling.c b/drivers/thermal/devfreq_cooling.c
index 01f0015f80dc..c549d83a0c7d 100644
--- a/drivers/thermal/devfreq_cooling.c
+++ b/drivers/thermal/devfreq_cooling.c
@@ -238,7 +238,7 @@ get_static_power(struct devfreq_cooling_device *dfc, unsigned long freq)
 		return 0;
 	}
 
-	return dfc->power_ops->get_static_power(voltage);
+	return dfc->power_ops->get_static_power(df, voltage);
 }
 
 /**
@@ -262,7 +262,8 @@ get_dynamic_power(struct devfreq_cooling_device *dfc, unsigned long freq,
 	struct devfreq_cooling_power *dfc_power = dfc->power_ops;
 
 	if (dfc_power->get_dynamic_power)
-		return dfc_power->get_dynamic_power(freq, voltage);
+		return dfc_power->get_dynamic_power(dfc->devfreq, freq,
+						    voltage);
 
 	freq_mhz = freq / 1000000;
 	power = (u64)dfc_power->dyn_power_coeff * freq_mhz * voltage * voltage;
diff --git a/include/linux/devfreq_cooling.h b/include/linux/devfreq_cooling.h
index 7adf6cc4b305..959714e93e5b 100644
--- a/include/linux/devfreq_cooling.h
+++ b/include/linux/devfreq_cooling.h
@@ -37,8 +37,10 @@
  *			@dyn_power_coeff * frequency * voltage^2
  */
 struct devfreq_cooling_power {
-	unsigned long (*get_static_power)(unsigned long voltage);
-	unsigned long (*get_dynamic_power)(unsigned long freq,
+	unsigned long (*get_static_power)(struct devfreq *devfreq,
+					  unsigned long voltage);
+	unsigned long (*get_dynamic_power)(struct devfreq *devfreq,
+					   unsigned long freq,
 					   unsigned long voltage);
 	unsigned long dyn_power_coeff;
 };
-- 
1.9.1