diff mbox series

[v3,1/4] devfreq: Register devfreq as a cooling device on demand

Message ID 20210307094519.9032-1-daniel.lezcano@linaro.org
State Superseded
Headers show
Series [v3,1/4] devfreq: Register devfreq as a cooling device on demand | expand

Commit Message

Daniel Lezcano March 7, 2021, 9:45 a.m. UTC
Currently the default behavior is to manually having the devfreq
backend to register themselves as a devfreq cooling device.

Instead of adding the code in the drivers for the thermal cooling
device registering, let's provide a flag in the devfreq's profile to
tell the common devfreq code to register the newly created devfreq as
a cooling device.

Suggested-by: Chanwoo Choi <cwchoi00@gmail.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>

---
 V3:
   - Rebased on linux-pm branch without units.h
   - Set the cdev to NULL in case of error
   - Added description for the cdev field in the devfreq structure
 V2:
   - Added is_cooling_device boolean in profile structure
   - Register cooling device when the is_cooling_device boolean is set
   - Remove devfreq cooling device registration in the backend drivers
 V1:
   - Register devfreq as a cooling device unconditionnally
---
 drivers/devfreq/devfreq.c | 13 +++++++++++++
 include/linux/devfreq.h   |  8 ++++++++
 2 files changed, 21 insertions(+)

-- 
2.17.1

Comments

Chanwoo Choi March 7, 2021, 2:15 p.m. UTC | #1
On 21. 3. 7. 오후 6:45, Daniel Lezcano wrote:
> Currently the default behavior is to manually having the devfreq

> backend to register themselves as a devfreq cooling device.

> 

> Instead of adding the code in the drivers for the thermal cooling

> device registering, let's provide a flag in the devfreq's profile to

> tell the common devfreq code to register the newly created devfreq as

> a cooling device.

> 

> Suggested-by: Chanwoo Choi <cwchoi00@gmail.com>

> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>

> ---

>   V3:

>     - Rebased on linux-pm branch without units.h

>     - Set the cdev to NULL in case of error

>     - Added description for the cdev field in the devfreq structure

>   V2:

>     - Added is_cooling_device boolean in profile structure

>     - Register cooling device when the is_cooling_device boolean is set

>     - Remove devfreq cooling device registration in the backend drivers

>   V1:

>     - Register devfreq as a cooling device unconditionnally

> ---

>   drivers/devfreq/devfreq.c | 13 +++++++++++++

>   include/linux/devfreq.h   |  8 ++++++++

>   2 files changed, 21 insertions(+)

> 

> diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c

> index bf3047896e41..cf64aeec468f 100644

> --- a/drivers/devfreq/devfreq.c

> +++ b/drivers/devfreq/devfreq.c

> @@ -11,6 +11,7 @@

>   #include <linux/kmod.h>

>   #include <linux/sched.h>

>   #include <linux/debugfs.h>

> +#include <linux/devfreq_cooling.h>

>   #include <linux/errno.h>

>   #include <linux/err.h>

>   #include <linux/init.h>

> @@ -26,6 +27,7 @@

>   #include <linux/hrtimer.h>

>   #include <linux/of.h>

>   #include <linux/pm_qos.h>

> +#include <linux/thermal.h>

>   #include "governor.h"

>   

>   #define CREATE_TRACE_POINTS

> @@ -935,6 +937,15 @@ struct devfreq *devfreq_add_device(struct device *dev,

>   

>   	mutex_unlock(&devfreq_list_lock);

>   

> +	if (devfreq->profile->is_cooling_device) {

> +		devfreq->cdev = devfreq_cooling_em_register(devfreq, NULL);

> +		if (IS_ERR(devfreq->cdev)) {

> +			dev_info(dev, "Failed to register devfreq "

> +				 "cooling device\n");

> +			devfreq->cdev = NULL;

> +		}

> +	}

> +

>   	return devfreq;

>   

>   err_init:

> @@ -960,6 +971,8 @@ int devfreq_remove_device(struct devfreq *devfreq)

>   	if (!devfreq)

>   		return -EINVAL;

>   

> +	thermal_cooling_device_unregister(devfreq->cdev);


I have a question. Why don't you use devfreq_cooling_unregister()?
When thermal_cooling_device_unregister(), how can we remove
the pm_qos_request of devfreq device?

> +

>   	if (devfreq->governor) {

>   		devfreq->governor->event_handler(devfreq,

>   						 DEVFREQ_GOV_STOP, NULL);

> diff --git a/include/linux/devfreq.h b/include/linux/devfreq.h

> index 26ea0850be9b..aba7ace11b72 100644

> --- a/include/linux/devfreq.h

> +++ b/include/linux/devfreq.h

> @@ -98,11 +98,15 @@ struct devfreq_dev_status {

>    * @freq_table:		Optional list of frequencies to support statistics

>    *			and freq_table must be generated in ascending order.

>    * @max_state:		The size of freq_table.

> + *

> + * @is_cooling_device: A self-explanatory boolean giving the device a

> + *                     cooling effect property.

>    */

>   struct devfreq_dev_profile {

>   	unsigned long initial_freq;

>   	unsigned int polling_ms;

>   	enum devfreq_timer timer;

> +	bool is_cooling_device;

>   

>   	int (*target)(struct device *dev, unsigned long *freq, u32 flags);

>   	int (*get_dev_status)(struct device *dev,

> @@ -156,6 +160,7 @@ struct devfreq_stats {

>    * @suspend_count:	 suspend requests counter for a device.

>    * @stats:	Statistics of devfreq device behavior

>    * @transition_notifier_list: list head of DEVFREQ_TRANSITION_NOTIFIER notifier

> + * @cdev:	Cooling device pointer if the devfreq has cooling property

>    * @nb_min:		Notifier block for DEV_PM_QOS_MIN_FREQUENCY

>    * @nb_max:		Notifier block for DEV_PM_QOS_MAX_FREQUENCY

>    *

> @@ -198,6 +203,9 @@ struct devfreq {

>   

>   	struct srcu_notifier_head transition_notifier_list;

>   

> +	/* Pointer to the cooling device if used for thermal mitigation */

> +	struct thermal_cooling_device *cdev;

> +

>   	struct notifier_block nb_min;

>   	struct notifier_block nb_max;

>   };

> 



-- 
Best Regards,
Samsung Electronics
Chanwoo Choi
Chanwoo Choi March 7, 2021, 2:16 p.m. UTC | #2
On 21. 3. 7. 오후 6:45, Daniel Lezcano wrote:
> Currently the default behavior is to manually having the devfreq

> backend to register themselves as a devfreq cooling device.

>

> Instead of adding the code in the drivers for the thermal cooling

> device registering, let's provide a flag in the devfreq's profile to

> tell the common devfreq code to register the newly created devfreq as

> a cooling device.

>

> Suggested-by: Chanwoo Choi <cwchoi00@gmail.com>

> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>

> ---

>   V3:

>     - Rebased on linux-pm branch without units.h

>     - Set the cdev to NULL in case of error

>     - Added description for the cdev field in the devfreq structure

>   V2:

>     - Added is_cooling_device boolean in profile structure

>     - Register cooling device when the is_cooling_device boolean is set

>     - Remove devfreq cooling device registration in the backend drivers

>   V1:

>     - Register devfreq as a cooling device unconditionnally

> ---

>   drivers/devfreq/devfreq.c | 13 +++++++++++++

>   include/linux/devfreq.h   |  8 ++++++++

>   2 files changed, 21 insertions(+)

>

> diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c

> index bf3047896e41..cf64aeec468f 100644

> --- a/drivers/devfreq/devfreq.c

> +++ b/drivers/devfreq/devfreq.c

> @@ -11,6 +11,7 @@

>   #include <linux/kmod.h>

>   #include <linux/sched.h>

>   #include <linux/debugfs.h>

> +#include <linux/devfreq_cooling.h>

>   #include <linux/errno.h>

>   #include <linux/err.h>

>   #include <linux/init.h>

> @@ -26,6 +27,7 @@

>   #include <linux/hrtimer.h>

>   #include <linux/of.h>

>   #include <linux/pm_qos.h>

> +#include <linux/thermal.h>

>   #include "governor.h"

>

>   #define CREATE_TRACE_POINTS

> @@ -935,6 +937,15 @@ struct devfreq *devfreq_add_device(struct device *dev,

>

>       mutex_unlock(&devfreq_list_lock);

>

> +     if (devfreq->profile->is_cooling_device) {

> +             devfreq->cdev = devfreq_cooling_em_register(devfreq, NULL);

> +             if (IS_ERR(devfreq->cdev)) {

> +                     dev_info(dev, "Failed to register devfreq "

> +                              "cooling device\n");

> +                     devfreq->cdev = NULL;

> +             }

> +     }

> +

>       return devfreq;

>

>   err_init:

> @@ -960,6 +971,8 @@ int devfreq_remove_device(struct devfreq *devfreq)

>       if (!devfreq)

>               return -EINVAL;

>

> +     thermal_cooling_device_unregister(devfreq->cdev);


I have a question. Why don't you use devfreq_cooling_unregister()?
When thermal_cooling_device_unregister(), how can we remove
the pm_qos_request of devfreq device?

> +

>       if (devfreq->governor) {

>               devfreq->governor->event_handler(devfreq,

>                                                DEVFREQ_GOV_STOP, NULL);

> diff --git a/include/linux/devfreq.h b/include/linux/devfreq.h

> index 26ea0850be9b..aba7ace11b72 100644

> --- a/include/linux/devfreq.h

> +++ b/include/linux/devfreq.h

> @@ -98,11 +98,15 @@ struct devfreq_dev_status {

>    * @freq_table:             Optional list of frequencies to support statistics

>    *                  and freq_table must be generated in ascending order.

>    * @max_state:              The size of freq_table.

> + *

> + * @is_cooling_device: A self-explanatory boolean giving the device a

> + *                     cooling effect property.

>    */

>   struct devfreq_dev_profile {

>       unsigned long initial_freq;

>       unsigned int polling_ms;

>       enum devfreq_timer timer;

> +     bool is_cooling_device;

>

>       int (*target)(struct device *dev, unsigned long *freq, u32 flags);

>       int (*get_dev_status)(struct device *dev,

> @@ -156,6 +160,7 @@ struct devfreq_stats {

>    * @suspend_count:   suspend requests counter for a device.

>    * @stats:  Statistics of devfreq device behavior

>    * @transition_notifier_list: list head of DEVFREQ_TRANSITION_NOTIFIER notifier

> + * @cdev:    Cooling device pointer if the devfreq has cooling property

>    * @nb_min:         Notifier block for DEV_PM_QOS_MIN_FREQUENCY

>    * @nb_max:         Notifier block for DEV_PM_QOS_MAX_FREQUENCY

>    *

> @@ -198,6 +203,9 @@ struct devfreq {

>

>       struct srcu_notifier_head transition_notifier_list;

>

> +     /* Pointer to the cooling device if used for thermal mitigation */

> +     struct thermal_cooling_device *cdev;

> +

>       struct notifier_block nb_min;

>       struct notifier_block nb_max;

>   };

>



--
Best Regards,
Samsung Electronics

Chanwoo Choi
Daniel Lezcano March 7, 2021, 2:28 p.m. UTC | #3
On 07/03/2021 15:16, Chanwoo Choi wrote:
> On 21. 3. 7. 오후 6:45, Daniel Lezcano wrote:

>> Currently the default behavior is to manually having the devfreq

>> backend to register themselves as a devfreq cooling device.

>>

>> Instead of adding the code in the drivers for the thermal cooling

>> device registering, let's provide a flag in the devfreq's profile to

>> tell the common devfreq code to register the newly created devfreq as

>> a cooling device.

>>

>> Suggested-by: Chanwoo Choi <cwchoi00@gmail.com>

>> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>

>> ---

>>   V3:

>>     - Rebased on linux-pm branch without units.h

>>     - Set the cdev to NULL in case of error

>>     - Added description for the cdev field in the devfreq structure

>>   V2:

>>     - Added is_cooling_device boolean in profile structure

>>     - Register cooling device when the is_cooling_device boolean is set

>>     - Remove devfreq cooling device registration in the backend drivers

>>   V1:

>>     - Register devfreq as a cooling device unconditionnally

>> ---



[ ... ]

>>       return devfreq;

>>

>>   err_init:

>> @@ -960,6 +971,8 @@ int devfreq_remove_device(struct devfreq *devfreq)

>>       if (!devfreq)

>>               return -EINVAL;

>>

>> +     thermal_cooling_device_unregister(devfreq->cdev);

> 

> I have a question. Why don't you use devfreq_cooling_unregister()?

> When thermal_cooling_device_unregister(), how can we remove

> the pm_qos_request of devfreq device?


You are perfectly right. I failed to call the right function :/

Will fix it with a v4.

-- 
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Chanwoo Choi March 7, 2021, 3:14 p.m. UTC | #4
On 21. 3. 7. 오후 11:28, Daniel Lezcano wrote:
> On 07/03/2021 15:16, Chanwoo Choi wrote:

>> On 21. 3. 7. 오후 6:45, Daniel Lezcano wrote:

>>> Currently the default behavior is to manually having the devfreq

>>> backend to register themselves as a devfreq cooling device.

>>>

>>> Instead of adding the code in the drivers for the thermal cooling

>>> device registering, let's provide a flag in the devfreq's profile to

>>> tell the common devfreq code to register the newly created devfreq as

>>> a cooling device.

>>>

>>> Suggested-by: Chanwoo Choi <cwchoi00@gmail.com>

>>> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>

>>> ---

>>>    V3:

>>>      - Rebased on linux-pm branch without units.h

>>>      - Set the cdev to NULL in case of error

>>>      - Added description for the cdev field in the devfreq structure

>>>    V2:

>>>      - Added is_cooling_device boolean in profile structure

>>>      - Register cooling device when the is_cooling_device boolean is set

>>>      - Remove devfreq cooling device registration in the backend drivers

>>>    V1:

>>>      - Register devfreq as a cooling device unconditionnally

>>> ---

> 

> 

> [ ... ]

> 

>>>        return devfreq;

>>>

>>>    err_init:

>>> @@ -960,6 +971,8 @@ int devfreq_remove_device(struct devfreq *devfreq)

>>>        if (!devfreq)

>>>                return -EINVAL;

>>>

>>> +     thermal_cooling_device_unregister(devfreq->cdev);

>>

>> I have a question. Why don't you use devfreq_cooling_unregister()?

>> When thermal_cooling_device_unregister(), how can we remove

>> the pm_qos_request of devfreq device?

> 

> You are perfectly right. I failed to call the right function :/

> 

> Will fix it with a v4.

> 


Thanks. And, please add 'PM /' prefix for patch in order to
keep the consistent patch title format.

PM / devfreq: Register devfreq as a cooling device on demand

-- 
Best Regards,
Samsung Electronics
Chanwoo Choi
Daniel Lezcano March 7, 2021, 3:16 p.m. UTC | #5
On 07/03/2021 16:14, Chanwoo Choi wrote:
> On 21. 3. 7. 오후 11:28, Daniel Lezcano wrote:


[ ... ]

> Thanks. And, please add 'PM /' prefix for patch in order to

> keep the consistent patch title format.

> 

> PM / devfreq: Register devfreq as a cooling device on demand


Sure, thanks

-- 
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diff mbox series

Patch

diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c
index bf3047896e41..cf64aeec468f 100644
--- a/drivers/devfreq/devfreq.c
+++ b/drivers/devfreq/devfreq.c
@@ -11,6 +11,7 @@ 
 #include <linux/kmod.h>
 #include <linux/sched.h>
 #include <linux/debugfs.h>
+#include <linux/devfreq_cooling.h>
 #include <linux/errno.h>
 #include <linux/err.h>
 #include <linux/init.h>
@@ -26,6 +27,7 @@ 
 #include <linux/hrtimer.h>
 #include <linux/of.h>
 #include <linux/pm_qos.h>
+#include <linux/thermal.h>
 #include "governor.h"
 
 #define CREATE_TRACE_POINTS
@@ -935,6 +937,15 @@  struct devfreq *devfreq_add_device(struct device *dev,
 
 	mutex_unlock(&devfreq_list_lock);
 
+	if (devfreq->profile->is_cooling_device) {
+		devfreq->cdev = devfreq_cooling_em_register(devfreq, NULL);
+		if (IS_ERR(devfreq->cdev)) {
+			dev_info(dev, "Failed to register devfreq "
+				 "cooling device\n");
+			devfreq->cdev = NULL;
+		}
+	}
+
 	return devfreq;
 
 err_init:
@@ -960,6 +971,8 @@  int devfreq_remove_device(struct devfreq *devfreq)
 	if (!devfreq)
 		return -EINVAL;
 
+	thermal_cooling_device_unregister(devfreq->cdev);
+
 	if (devfreq->governor) {
 		devfreq->governor->event_handler(devfreq,
 						 DEVFREQ_GOV_STOP, NULL);
diff --git a/include/linux/devfreq.h b/include/linux/devfreq.h
index 26ea0850be9b..aba7ace11b72 100644
--- a/include/linux/devfreq.h
+++ b/include/linux/devfreq.h
@@ -98,11 +98,15 @@  struct devfreq_dev_status {
  * @freq_table:		Optional list of frequencies to support statistics
  *			and freq_table must be generated in ascending order.
  * @max_state:		The size of freq_table.
+ *
+ * @is_cooling_device: A self-explanatory boolean giving the device a
+ *                     cooling effect property.
  */
 struct devfreq_dev_profile {
 	unsigned long initial_freq;
 	unsigned int polling_ms;
 	enum devfreq_timer timer;
+	bool is_cooling_device;
 
 	int (*target)(struct device *dev, unsigned long *freq, u32 flags);
 	int (*get_dev_status)(struct device *dev,
@@ -156,6 +160,7 @@  struct devfreq_stats {
  * @suspend_count:	 suspend requests counter for a device.
  * @stats:	Statistics of devfreq device behavior
  * @transition_notifier_list: list head of DEVFREQ_TRANSITION_NOTIFIER notifier
+ * @cdev:	Cooling device pointer if the devfreq has cooling property
  * @nb_min:		Notifier block for DEV_PM_QOS_MIN_FREQUENCY
  * @nb_max:		Notifier block for DEV_PM_QOS_MAX_FREQUENCY
  *
@@ -198,6 +203,9 @@  struct devfreq {
 
 	struct srcu_notifier_head transition_notifier_list;
 
+	/* Pointer to the cooling device if used for thermal mitigation */
+	struct thermal_cooling_device *cdev;
+
 	struct notifier_block nb_min;
 	struct notifier_block nb_max;
 };