diff mbox

[V3,3/5] Thermal: Remove the cooling_cpufreq_list.

Message ID 1351615741-24134-4-git-send-email-hongbo.zhang@linaro.com (mailing list archive)
State Not Applicable, archived
Headers show

Commit Message

Hongbo Zhang Oct. 30, 2012, 4:48 p.m. UTC
From: "hongbo.zhang" <hongbo.zhang@linaro.com>

Problem of using this list is that the cpufreq_get_max_state callback will be
called when register cooling device by thermal_cooling_device_register, but
this list isn't ready at this moment. What's more, there is no need to maintain
such a list, we can get cpufreq_cooling_device instance by the private
thermal_cooling_device.devdata.

Signed-off-by: hongbo.zhang <hongbo.zhang@linaro.com>
Reviewed-by: Francesco Lavra <francescolavra.fl@gmail.com>
Reviewed-by: Amit Daniel Kachhap <amit.kachhap@linaro.org>
---
 drivers/thermal/cpu_cooling.c | 91 +++++++++----------------------------------
 1 file changed, 19 insertions(+), 72 deletions(-)

Comments

Zhang Rui Nov. 7, 2012, 6:54 a.m. UTC | #1
On Tue, 2012-10-30 at 17:48 +0100, hongbo.zhang wrote:
> From: "hongbo.zhang" <hongbo.zhang@linaro.com>
> 
> Problem of using this list is that the cpufreq_get_max_state callback will be
> called when register cooling device by thermal_cooling_device_register, but
> this list isn't ready at this moment. What's more, there is no need to maintain
> such a list, we can get cpufreq_cooling_device instance by the private
> thermal_cooling_device.devdata.
> 
> Signed-off-by: hongbo.zhang <hongbo.zhang@linaro.com>
> Reviewed-by: Francesco Lavra <francescolavra.fl@gmail.com>
> Reviewed-by: Amit Daniel Kachhap <amit.kachhap@linaro.org>

applied to thermal-next.

thanks,
rui

> ---
>  drivers/thermal/cpu_cooling.c | 91 +++++++++----------------------------------
>  1 file changed, 19 insertions(+), 72 deletions(-)
> 
> diff --git a/drivers/thermal/cpu_cooling.c b/drivers/thermal/cpu_cooling.c
> index bfd62b7..392d57d 100644
> --- a/drivers/thermal/cpu_cooling.c
> +++ b/drivers/thermal/cpu_cooling.c
> @@ -58,8 +58,9 @@ struct cpufreq_cooling_device {
>  };
>  static LIST_HEAD(cooling_cpufreq_list);
>  static DEFINE_IDR(cpufreq_idr);
> +static DEFINE_MUTEX(cooling_cpufreq_lock);
>  
> -static struct mutex cooling_cpufreq_lock;
> +static unsigned int cpufreq_dev_count;
>  
>  /* notify_table passes value to the CPUFREQ_ADJUST callback function. */
>  #define NOTIFY_INVALID NULL
> @@ -240,28 +241,18 @@ static int cpufreq_thermal_notifier(struct notifier_block *nb,
>  static int cpufreq_get_max_state(struct thermal_cooling_device *cdev,
>  				 unsigned long *state)
>  {
> -	int ret = -EINVAL, i = 0;
> -	struct cpufreq_cooling_device *cpufreq_device;
> -	struct cpumask *maskPtr;
> +	struct cpufreq_cooling_device *cpufreq_device = cdev->devdata;
> +	struct cpumask *maskPtr = &cpufreq_device->allowed_cpus;
>  	unsigned int cpu;
>  	struct cpufreq_frequency_table *table;
>  	unsigned long count = 0;
> +	int i = 0;
>  
> -	mutex_lock(&cooling_cpufreq_lock);
> -	list_for_each_entry(cpufreq_device, &cooling_cpufreq_list, node) {
> -		if (cpufreq_device && cpufreq_device->cool_dev == cdev)
> -			break;
> -	}
> -	if (cpufreq_device == NULL)
> -		goto return_get_max_state;
> -
> -	maskPtr = &cpufreq_device->allowed_cpus;
>  	cpu = cpumask_any(maskPtr);
>  	table = cpufreq_frequency_get_table(cpu);
>  	if (!table) {
>  		*state = 0;
> -		ret = 0;
> -		goto return_get_max_state;
> +		return 0;
>  	}
>  
>  	for (i = 0; (table[i].frequency != CPUFREQ_TABLE_END); i++) {
> @@ -272,12 +263,10 @@ static int cpufreq_get_max_state(struct thermal_cooling_device *cdev,
>  
>  	if (count > 0) {
>  		*state = --count;
> -		ret = 0;
> +		return 0;
>  	}
>  
> -return_get_max_state:
> -	mutex_unlock(&cooling_cpufreq_lock);
> -	return ret;
> +	return -EINVAL;
>  }
>  
>  /**
> @@ -288,20 +277,10 @@ return_get_max_state:
>  static int cpufreq_get_cur_state(struct thermal_cooling_device *cdev,
>  				 unsigned long *state)
>  {
> -	int ret = -EINVAL;
> -	struct cpufreq_cooling_device *cpufreq_device;
> +	struct cpufreq_cooling_device *cpufreq_device = cdev->devdata;
>  
> -	mutex_lock(&cooling_cpufreq_lock);
> -	list_for_each_entry(cpufreq_device, &cooling_cpufreq_list, node) {
> -		if (cpufreq_device && cpufreq_device->cool_dev == cdev) {
> -			*state = cpufreq_device->cpufreq_state;
> -			ret = 0;
> -			break;
> -		}
> -	}
> -	mutex_unlock(&cooling_cpufreq_lock);
> -
> -	return ret;
> +	*state = cpufreq_device->cpufreq_state;
> +	return 0;
>  }
>  
>  /**
> @@ -312,22 +291,9 @@ static int cpufreq_get_cur_state(struct thermal_cooling_device *cdev,
>  static int cpufreq_set_cur_state(struct thermal_cooling_device *cdev,
>  				 unsigned long state)
>  {
> -	int ret = -EINVAL;
> -	struct cpufreq_cooling_device *cpufreq_device;
> +	struct cpufreq_cooling_device *cpufreq_device = cdev->devdata;
>  
> -	mutex_lock(&cooling_cpufreq_lock);
> -	list_for_each_entry(cpufreq_device, &cooling_cpufreq_list, node) {
> -		if (cpufreq_device && cpufreq_device->cool_dev == cdev) {
> -			ret = 0;
> -			break;
> -		}
> -	}
> -	if (!ret)
> -		ret = cpufreq_apply_cooling(cpufreq_device, state);
> -
> -	mutex_unlock(&cooling_cpufreq_lock);
> -
> -	return ret;
> +	return cpufreq_apply_cooling(cpufreq_device, state);
>  }
>  
>  /* Bind cpufreq callbacks to thermal cooling device ops */
> @@ -351,14 +317,11 @@ struct thermal_cooling_device *cpufreq_cooling_register(
>  {
>  	struct thermal_cooling_device *cool_dev;
>  	struct cpufreq_cooling_device *cpufreq_dev = NULL;
> -	unsigned int cpufreq_dev_count = 0, min = 0, max = 0;
> +	unsigned int min = 0, max = 0;
>  	char dev_name[THERMAL_NAME_LENGTH];
>  	int ret = 0, i;
>  	struct cpufreq_policy policy;
>  
> -	list_for_each_entry(cpufreq_dev, &cooling_cpufreq_list, node)
> -		cpufreq_dev_count++;
> -
>  	/*Verify that all the clip cpus have same freq_min, freq_max limit*/
>  	for_each_cpu(i, clip_cpus) {
>  		/*continue if cpufreq policy not found and not return error*/
> @@ -380,9 +343,6 @@ struct thermal_cooling_device *cpufreq_cooling_register(
>  
>  	cpumask_copy(&cpufreq_dev->allowed_cpus, clip_cpus);
>  
> -	if (cpufreq_dev_count == 0)
> -		mutex_init(&cooling_cpufreq_lock);
> -
>  	ret = get_idr(&cpufreq_idr, &cpufreq_dev->id);
>  	if (ret) {
>  		kfree(cpufreq_dev);
> @@ -401,12 +361,12 @@ struct thermal_cooling_device *cpufreq_cooling_register(
>  	cpufreq_dev->cool_dev = cool_dev;
>  	cpufreq_dev->cpufreq_state = 0;
>  	mutex_lock(&cooling_cpufreq_lock);
> -	list_add_tail(&cpufreq_dev->node, &cooling_cpufreq_list);
>  
>  	/* Register the notifier for first cpufreq cooling device */
>  	if (cpufreq_dev_count == 0)
>  		cpufreq_register_notifier(&thermal_cpufreq_notifier_block,
>  						CPUFREQ_POLICY_NOTIFIER);
> +	cpufreq_dev_count++;
>  
>  	mutex_unlock(&cooling_cpufreq_lock);
>  	return cool_dev;
> @@ -419,33 +379,20 @@ EXPORT_SYMBOL(cpufreq_cooling_register);
>   */
>  void cpufreq_cooling_unregister(struct thermal_cooling_device *cdev)
>  {
> -	struct cpufreq_cooling_device *cpufreq_dev = NULL;
> -	unsigned int cpufreq_dev_count = 0;
> +	struct cpufreq_cooling_device *cpufreq_dev = cdev->devdata;
>  
>  	mutex_lock(&cooling_cpufreq_lock);
> -	list_for_each_entry(cpufreq_dev, &cooling_cpufreq_list, node) {
> -		if (cpufreq_dev && cpufreq_dev->cool_dev == cdev)
> -			break;
> -		cpufreq_dev_count++;
> -	}
> -
> -	if (!cpufreq_dev || cpufreq_dev->cool_dev != cdev) {
> -		mutex_unlock(&cooling_cpufreq_lock);
> -		return;
> -	}
> -
> -	list_del(&cpufreq_dev->node);
> +	cpufreq_dev_count--;
>  
>  	/* Unregister the notifier for the last cpufreq cooling device */
> -	if (cpufreq_dev_count == 1) {
> +	if (cpufreq_dev_count == 0) {
>  		cpufreq_unregister_notifier(&thermal_cpufreq_notifier_block,
>  					CPUFREQ_POLICY_NOTIFIER);
>  	}
>  	mutex_unlock(&cooling_cpufreq_lock);
> +
>  	thermal_cooling_device_unregister(cpufreq_dev->cool_dev);
>  	release_idr(&cpufreq_idr, cpufreq_dev->id);
> -	if (cpufreq_dev_count == 1)
> -		mutex_destroy(&cooling_cpufreq_lock);
>  	kfree(cpufreq_dev);
>  }
>  EXPORT_SYMBOL(cpufreq_cooling_unregister);


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Hongbo Zhang Nov. 9, 2012, 11:54 a.m. UTC | #2
On 7 November 2012 14:54, Zhang Rui <rui.zhang@intel.com> wrote:
> On Tue, 2012-10-30 at 17:48 +0100, hongbo.zhang wrote:
>> From: "hongbo.zhang" <hongbo.zhang@linaro.com>
>>
>> Problem of using this list is that the cpufreq_get_max_state callback will be
>> called when register cooling device by thermal_cooling_device_register, but
>> this list isn't ready at this moment. What's more, there is no need to maintain
>> such a list, we can get cpufreq_cooling_device instance by the private
>> thermal_cooling_device.devdata.
>>
>> Signed-off-by: hongbo.zhang <hongbo.zhang@linaro.com>
>> Reviewed-by: Francesco Lavra <francescolavra.fl@gmail.com>
>> Reviewed-by: Amit Daniel Kachhap <amit.kachhap@linaro.org>
>
> applied to thermal-next.
Thanks.
I have sent the other updated 4/5 5/5 patches with Reviewed-by added
in a new thread, please have a look there.

>
> thanks,
> rui
>
>> ---
>>  drivers/thermal/cpu_cooling.c | 91 +++++++++----------------------------------
>>  1 file changed, 19 insertions(+), 72 deletions(-)
>>
>> diff --git a/drivers/thermal/cpu_cooling.c b/drivers/thermal/cpu_cooling.c
>> index bfd62b7..392d57d 100644
>> --- a/drivers/thermal/cpu_cooling.c
>> +++ b/drivers/thermal/cpu_cooling.c
>> @@ -58,8 +58,9 @@ struct cpufreq_cooling_device {
>>  };
>>  static LIST_HEAD(cooling_cpufreq_list);
>>  static DEFINE_IDR(cpufreq_idr);
>> +static DEFINE_MUTEX(cooling_cpufreq_lock);
>>
>> -static struct mutex cooling_cpufreq_lock;
>> +static unsigned int cpufreq_dev_count;
>>
>>  /* notify_table passes value to the CPUFREQ_ADJUST callback function. */
>>  #define NOTIFY_INVALID NULL
>> @@ -240,28 +241,18 @@ static int cpufreq_thermal_notifier(struct notifier_block *nb,
>>  static int cpufreq_get_max_state(struct thermal_cooling_device *cdev,
>>                                unsigned long *state)
>>  {
>> -     int ret = -EINVAL, i = 0;
>> -     struct cpufreq_cooling_device *cpufreq_device;
>> -     struct cpumask *maskPtr;
>> +     struct cpufreq_cooling_device *cpufreq_device = cdev->devdata;
>> +     struct cpumask *maskPtr = &cpufreq_device->allowed_cpus;
>>       unsigned int cpu;
>>       struct cpufreq_frequency_table *table;
>>       unsigned long count = 0;
>> +     int i = 0;
>>
>> -     mutex_lock(&cooling_cpufreq_lock);
>> -     list_for_each_entry(cpufreq_device, &cooling_cpufreq_list, node) {
>> -             if (cpufreq_device && cpufreq_device->cool_dev == cdev)
>> -                     break;
>> -     }
>> -     if (cpufreq_device == NULL)
>> -             goto return_get_max_state;
>> -
>> -     maskPtr = &cpufreq_device->allowed_cpus;
>>       cpu = cpumask_any(maskPtr);
>>       table = cpufreq_frequency_get_table(cpu);
>>       if (!table) {
>>               *state = 0;
>> -             ret = 0;
>> -             goto return_get_max_state;
>> +             return 0;
>>       }
>>
>>       for (i = 0; (table[i].frequency != CPUFREQ_TABLE_END); i++) {
>> @@ -272,12 +263,10 @@ static int cpufreq_get_max_state(struct thermal_cooling_device *cdev,
>>
>>       if (count > 0) {
>>               *state = --count;
>> -             ret = 0;
>> +             return 0;
>>       }
>>
>> -return_get_max_state:
>> -     mutex_unlock(&cooling_cpufreq_lock);
>> -     return ret;
>> +     return -EINVAL;
>>  }
>>
>>  /**
>> @@ -288,20 +277,10 @@ return_get_max_state:
>>  static int cpufreq_get_cur_state(struct thermal_cooling_device *cdev,
>>                                unsigned long *state)
>>  {
>> -     int ret = -EINVAL;
>> -     struct cpufreq_cooling_device *cpufreq_device;
>> +     struct cpufreq_cooling_device *cpufreq_device = cdev->devdata;
>>
>> -     mutex_lock(&cooling_cpufreq_lock);
>> -     list_for_each_entry(cpufreq_device, &cooling_cpufreq_list, node) {
>> -             if (cpufreq_device && cpufreq_device->cool_dev == cdev) {
>> -                     *state = cpufreq_device->cpufreq_state;
>> -                     ret = 0;
>> -                     break;
>> -             }
>> -     }
>> -     mutex_unlock(&cooling_cpufreq_lock);
>> -
>> -     return ret;
>> +     *state = cpufreq_device->cpufreq_state;
>> +     return 0;
>>  }
>>
>>  /**
>> @@ -312,22 +291,9 @@ static int cpufreq_get_cur_state(struct thermal_cooling_device *cdev,
>>  static int cpufreq_set_cur_state(struct thermal_cooling_device *cdev,
>>                                unsigned long state)
>>  {
>> -     int ret = -EINVAL;
>> -     struct cpufreq_cooling_device *cpufreq_device;
>> +     struct cpufreq_cooling_device *cpufreq_device = cdev->devdata;
>>
>> -     mutex_lock(&cooling_cpufreq_lock);
>> -     list_for_each_entry(cpufreq_device, &cooling_cpufreq_list, node) {
>> -             if (cpufreq_device && cpufreq_device->cool_dev == cdev) {
>> -                     ret = 0;
>> -                     break;
>> -             }
>> -     }
>> -     if (!ret)
>> -             ret = cpufreq_apply_cooling(cpufreq_device, state);
>> -
>> -     mutex_unlock(&cooling_cpufreq_lock);
>> -
>> -     return ret;
>> +     return cpufreq_apply_cooling(cpufreq_device, state);
>>  }
>>
>>  /* Bind cpufreq callbacks to thermal cooling device ops */
>> @@ -351,14 +317,11 @@ struct thermal_cooling_device *cpufreq_cooling_register(
>>  {
>>       struct thermal_cooling_device *cool_dev;
>>       struct cpufreq_cooling_device *cpufreq_dev = NULL;
>> -     unsigned int cpufreq_dev_count = 0, min = 0, max = 0;
>> +     unsigned int min = 0, max = 0;
>>       char dev_name[THERMAL_NAME_LENGTH];
>>       int ret = 0, i;
>>       struct cpufreq_policy policy;
>>
>> -     list_for_each_entry(cpufreq_dev, &cooling_cpufreq_list, node)
>> -             cpufreq_dev_count++;
>> -
>>       /*Verify that all the clip cpus have same freq_min, freq_max limit*/
>>       for_each_cpu(i, clip_cpus) {
>>               /*continue if cpufreq policy not found and not return error*/
>> @@ -380,9 +343,6 @@ struct thermal_cooling_device *cpufreq_cooling_register(
>>
>>       cpumask_copy(&cpufreq_dev->allowed_cpus, clip_cpus);
>>
>> -     if (cpufreq_dev_count == 0)
>> -             mutex_init(&cooling_cpufreq_lock);
>> -
>>       ret = get_idr(&cpufreq_idr, &cpufreq_dev->id);
>>       if (ret) {
>>               kfree(cpufreq_dev);
>> @@ -401,12 +361,12 @@ struct thermal_cooling_device *cpufreq_cooling_register(
>>       cpufreq_dev->cool_dev = cool_dev;
>>       cpufreq_dev->cpufreq_state = 0;
>>       mutex_lock(&cooling_cpufreq_lock);
>> -     list_add_tail(&cpufreq_dev->node, &cooling_cpufreq_list);
>>
>>       /* Register the notifier for first cpufreq cooling device */
>>       if (cpufreq_dev_count == 0)
>>               cpufreq_register_notifier(&thermal_cpufreq_notifier_block,
>>                                               CPUFREQ_POLICY_NOTIFIER);
>> +     cpufreq_dev_count++;
>>
>>       mutex_unlock(&cooling_cpufreq_lock);
>>       return cool_dev;
>> @@ -419,33 +379,20 @@ EXPORT_SYMBOL(cpufreq_cooling_register);
>>   */
>>  void cpufreq_cooling_unregister(struct thermal_cooling_device *cdev)
>>  {
>> -     struct cpufreq_cooling_device *cpufreq_dev = NULL;
>> -     unsigned int cpufreq_dev_count = 0;
>> +     struct cpufreq_cooling_device *cpufreq_dev = cdev->devdata;
>>
>>       mutex_lock(&cooling_cpufreq_lock);
>> -     list_for_each_entry(cpufreq_dev, &cooling_cpufreq_list, node) {
>> -             if (cpufreq_dev && cpufreq_dev->cool_dev == cdev)
>> -                     break;
>> -             cpufreq_dev_count++;
>> -     }
>> -
>> -     if (!cpufreq_dev || cpufreq_dev->cool_dev != cdev) {
>> -             mutex_unlock(&cooling_cpufreq_lock);
>> -             return;
>> -     }
>> -
>> -     list_del(&cpufreq_dev->node);
>> +     cpufreq_dev_count--;
>>
>>       /* Unregister the notifier for the last cpufreq cooling device */
>> -     if (cpufreq_dev_count == 1) {
>> +     if (cpufreq_dev_count == 0) {
>>               cpufreq_unregister_notifier(&thermal_cpufreq_notifier_block,
>>                                       CPUFREQ_POLICY_NOTIFIER);
>>       }
>>       mutex_unlock(&cooling_cpufreq_lock);
>> +
>>       thermal_cooling_device_unregister(cpufreq_dev->cool_dev);
>>       release_idr(&cpufreq_idr, cpufreq_dev->id);
>> -     if (cpufreq_dev_count == 1)
>> -             mutex_destroy(&cooling_cpufreq_lock);
>>       kfree(cpufreq_dev);
>>  }
>>  EXPORT_SYMBOL(cpufreq_cooling_unregister);
>
>
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diff mbox

Patch

diff --git a/drivers/thermal/cpu_cooling.c b/drivers/thermal/cpu_cooling.c
index bfd62b7..392d57d 100644
--- a/drivers/thermal/cpu_cooling.c
+++ b/drivers/thermal/cpu_cooling.c
@@ -58,8 +58,9 @@  struct cpufreq_cooling_device {
 };
 static LIST_HEAD(cooling_cpufreq_list);
 static DEFINE_IDR(cpufreq_idr);
+static DEFINE_MUTEX(cooling_cpufreq_lock);
 
-static struct mutex cooling_cpufreq_lock;
+static unsigned int cpufreq_dev_count;
 
 /* notify_table passes value to the CPUFREQ_ADJUST callback function. */
 #define NOTIFY_INVALID NULL
@@ -240,28 +241,18 @@  static int cpufreq_thermal_notifier(struct notifier_block *nb,
 static int cpufreq_get_max_state(struct thermal_cooling_device *cdev,
 				 unsigned long *state)
 {
-	int ret = -EINVAL, i = 0;
-	struct cpufreq_cooling_device *cpufreq_device;
-	struct cpumask *maskPtr;
+	struct cpufreq_cooling_device *cpufreq_device = cdev->devdata;
+	struct cpumask *maskPtr = &cpufreq_device->allowed_cpus;
 	unsigned int cpu;
 	struct cpufreq_frequency_table *table;
 	unsigned long count = 0;
+	int i = 0;
 
-	mutex_lock(&cooling_cpufreq_lock);
-	list_for_each_entry(cpufreq_device, &cooling_cpufreq_list, node) {
-		if (cpufreq_device && cpufreq_device->cool_dev == cdev)
-			break;
-	}
-	if (cpufreq_device == NULL)
-		goto return_get_max_state;
-
-	maskPtr = &cpufreq_device->allowed_cpus;
 	cpu = cpumask_any(maskPtr);
 	table = cpufreq_frequency_get_table(cpu);
 	if (!table) {
 		*state = 0;
-		ret = 0;
-		goto return_get_max_state;
+		return 0;
 	}
 
 	for (i = 0; (table[i].frequency != CPUFREQ_TABLE_END); i++) {
@@ -272,12 +263,10 @@  static int cpufreq_get_max_state(struct thermal_cooling_device *cdev,
 
 	if (count > 0) {
 		*state = --count;
-		ret = 0;
+		return 0;
 	}
 
-return_get_max_state:
-	mutex_unlock(&cooling_cpufreq_lock);
-	return ret;
+	return -EINVAL;
 }
 
 /**
@@ -288,20 +277,10 @@  return_get_max_state:
 static int cpufreq_get_cur_state(struct thermal_cooling_device *cdev,
 				 unsigned long *state)
 {
-	int ret = -EINVAL;
-	struct cpufreq_cooling_device *cpufreq_device;
+	struct cpufreq_cooling_device *cpufreq_device = cdev->devdata;
 
-	mutex_lock(&cooling_cpufreq_lock);
-	list_for_each_entry(cpufreq_device, &cooling_cpufreq_list, node) {
-		if (cpufreq_device && cpufreq_device->cool_dev == cdev) {
-			*state = cpufreq_device->cpufreq_state;
-			ret = 0;
-			break;
-		}
-	}
-	mutex_unlock(&cooling_cpufreq_lock);
-
-	return ret;
+	*state = cpufreq_device->cpufreq_state;
+	return 0;
 }
 
 /**
@@ -312,22 +291,9 @@  static int cpufreq_get_cur_state(struct thermal_cooling_device *cdev,
 static int cpufreq_set_cur_state(struct thermal_cooling_device *cdev,
 				 unsigned long state)
 {
-	int ret = -EINVAL;
-	struct cpufreq_cooling_device *cpufreq_device;
+	struct cpufreq_cooling_device *cpufreq_device = cdev->devdata;
 
-	mutex_lock(&cooling_cpufreq_lock);
-	list_for_each_entry(cpufreq_device, &cooling_cpufreq_list, node) {
-		if (cpufreq_device && cpufreq_device->cool_dev == cdev) {
-			ret = 0;
-			break;
-		}
-	}
-	if (!ret)
-		ret = cpufreq_apply_cooling(cpufreq_device, state);
-
-	mutex_unlock(&cooling_cpufreq_lock);
-
-	return ret;
+	return cpufreq_apply_cooling(cpufreq_device, state);
 }
 
 /* Bind cpufreq callbacks to thermal cooling device ops */
@@ -351,14 +317,11 @@  struct thermal_cooling_device *cpufreq_cooling_register(
 {
 	struct thermal_cooling_device *cool_dev;
 	struct cpufreq_cooling_device *cpufreq_dev = NULL;
-	unsigned int cpufreq_dev_count = 0, min = 0, max = 0;
+	unsigned int min = 0, max = 0;
 	char dev_name[THERMAL_NAME_LENGTH];
 	int ret = 0, i;
 	struct cpufreq_policy policy;
 
-	list_for_each_entry(cpufreq_dev, &cooling_cpufreq_list, node)
-		cpufreq_dev_count++;
-
 	/*Verify that all the clip cpus have same freq_min, freq_max limit*/
 	for_each_cpu(i, clip_cpus) {
 		/*continue if cpufreq policy not found and not return error*/
@@ -380,9 +343,6 @@  struct thermal_cooling_device *cpufreq_cooling_register(
 
 	cpumask_copy(&cpufreq_dev->allowed_cpus, clip_cpus);
 
-	if (cpufreq_dev_count == 0)
-		mutex_init(&cooling_cpufreq_lock);
-
 	ret = get_idr(&cpufreq_idr, &cpufreq_dev->id);
 	if (ret) {
 		kfree(cpufreq_dev);
@@ -401,12 +361,12 @@  struct thermal_cooling_device *cpufreq_cooling_register(
 	cpufreq_dev->cool_dev = cool_dev;
 	cpufreq_dev->cpufreq_state = 0;
 	mutex_lock(&cooling_cpufreq_lock);
-	list_add_tail(&cpufreq_dev->node, &cooling_cpufreq_list);
 
 	/* Register the notifier for first cpufreq cooling device */
 	if (cpufreq_dev_count == 0)
 		cpufreq_register_notifier(&thermal_cpufreq_notifier_block,
 						CPUFREQ_POLICY_NOTIFIER);
+	cpufreq_dev_count++;
 
 	mutex_unlock(&cooling_cpufreq_lock);
 	return cool_dev;
@@ -419,33 +379,20 @@  EXPORT_SYMBOL(cpufreq_cooling_register);
  */
 void cpufreq_cooling_unregister(struct thermal_cooling_device *cdev)
 {
-	struct cpufreq_cooling_device *cpufreq_dev = NULL;
-	unsigned int cpufreq_dev_count = 0;
+	struct cpufreq_cooling_device *cpufreq_dev = cdev->devdata;
 
 	mutex_lock(&cooling_cpufreq_lock);
-	list_for_each_entry(cpufreq_dev, &cooling_cpufreq_list, node) {
-		if (cpufreq_dev && cpufreq_dev->cool_dev == cdev)
-			break;
-		cpufreq_dev_count++;
-	}
-
-	if (!cpufreq_dev || cpufreq_dev->cool_dev != cdev) {
-		mutex_unlock(&cooling_cpufreq_lock);
-		return;
-	}
-
-	list_del(&cpufreq_dev->node);
+	cpufreq_dev_count--;
 
 	/* Unregister the notifier for the last cpufreq cooling device */
-	if (cpufreq_dev_count == 1) {
+	if (cpufreq_dev_count == 0) {
 		cpufreq_unregister_notifier(&thermal_cpufreq_notifier_block,
 					CPUFREQ_POLICY_NOTIFIER);
 	}
 	mutex_unlock(&cooling_cpufreq_lock);
+
 	thermal_cooling_device_unregister(cpufreq_dev->cool_dev);
 	release_idr(&cpufreq_idr, cpufreq_dev->id);
-	if (cpufreq_dev_count == 1)
-		mutex_destroy(&cooling_cpufreq_lock);
 	kfree(cpufreq_dev);
 }
 EXPORT_SYMBOL(cpufreq_cooling_unregister);