| Message ID | 20221014094359.100995-1-kant@allwinnertech.com |
|---|---|
| State | Accepted |
| Commit | 5fdded8448924e3631d466eea499b11606c43640 |
| Headers | show |
| Series | [v3] PM/devfreq: governor: Add a private governor_data for governor | expand |
Hi, Looks good to me. But, you need to send it to the stable mailing list too as I commented on previous mail. Please add stable@vger.kernel.org to Cc. On 22. 10. 14. 18:43, Kant Fan wrote: > The member void *data in the structure devfreq can be overwrite > by governor_userspace. For example: > 1. The device driver assigned the devfreq governor to simple_ondemand > by the function devfreq_add_device() and init the devfreq member > void *data to a pointer of a static structure devfreq_simple_ondemand_data > by the function devfreq_add_device(). > 2. The user changed the devfreq governor to userspace by the command > "echo userspace > /sys/class/devfreq/.../governor". > 3. The governor userspace alloced a dynamic memory for the struct > userspace_data and assigend the member void *data of devfreq to > this memory by the function userspace_init(). > 4. The user changed the devfreq governor back to simple_ondemand > by the command "echo simple_ondemand > /sys/class/devfreq/.../governor". > 5. The governor userspace exited and assigned the member void *data > in the structure devfreq to NULL by the function userspace_exit(). > 6. The governor simple_ondemand fetched the static information of > devfreq_simple_ondemand_data in the function > devfreq_simple_ondemand_func() but the member void *data of devfreq was > assigned to NULL by the function userspace_exit(). > 7. The information of upthreshold and downdifferential is lost > and the governor simple_ondemand can't work correctly. > > The member void *data in the structure devfreq is designed for > a static pointer used in a governor and inited by the function > devfreq_add_device(). This patch add an element named governor_data > in the devfreq structure which can be used by a governor(E.g userspace) > who want to assign a private data to do some private things. > > Fixes: ce26c5bb9569 ("PM / devfreq: Add basic governors") > > Acked-by: MyungJoo Ham <myungjoo.ham@samsung.com> > > Signed-off-by: Kant Fan <kant@allwinnertech.com> > --- > drivers/devfreq/devfreq.c | 6 ++---- > drivers/devfreq/governor_userspace.c | 12 ++++++------ > include/linux/devfreq.h | 7 ++++--- > 3 files changed, 12 insertions(+), 13 deletions(-) > > diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c > index 63347a5ae599..8c5f6f7fca11 100644 > --- a/drivers/devfreq/devfreq.c > +++ b/drivers/devfreq/devfreq.c > @@ -776,8 +776,7 @@ static void remove_sysfs_files(struct devfreq *devfreq, > * @dev: the device to add devfreq feature. > * @profile: device-specific profile to run devfreq. > * @governor_name: name of the policy to choose frequency. > - * @data: private data for the governor. The devfreq framework does not > - * touch this value. > + * @data: devfreq driver pass to governors, governor should not change it. > */ > struct devfreq *devfreq_add_device(struct device *dev, > struct devfreq_dev_profile *profile, > @@ -1011,8 +1010,7 @@ static void devm_devfreq_dev_release(struct device *dev, void *res) > * @dev: the device to add devfreq feature. > * @profile: device-specific profile to run devfreq. > * @governor_name: name of the policy to choose frequency. > - * @data: private data for the governor. The devfreq framework does not > - * touch this value. > + * @data: devfreq driver pass to governors, governor should not change it. > * > * This function manages automatically the memory of devfreq device using device > * resource management and simplify the free operation for memory of devfreq > diff --git a/drivers/devfreq/governor_userspace.c b/drivers/devfreq/governor_userspace.c > index ab9db7adb3ad..d69672ccacc4 100644 > --- a/drivers/devfreq/governor_userspace.c > +++ b/drivers/devfreq/governor_userspace.c > @@ -21,7 +21,7 @@ struct userspace_data { > > static int devfreq_userspace_func(struct devfreq *df, unsigned long *freq) > { > - struct userspace_data *data = df->data; > + struct userspace_data *data = df->governor_data; > > if (data->valid) > *freq = data->user_frequency; > @@ -40,7 +40,7 @@ static ssize_t set_freq_store(struct device *dev, struct device_attribute *attr, > int err = 0; > > mutex_lock(&devfreq->lock); > - data = devfreq->data; > + data = devfreq->governor_data; > > sscanf(buf, "%lu", &wanted); > data->user_frequency = wanted; > @@ -60,7 +60,7 @@ static ssize_t set_freq_show(struct device *dev, > int err = 0; > > mutex_lock(&devfreq->lock); > - data = devfreq->data; > + data = devfreq->governor_data; > > if (data->valid) > err = sprintf(buf, "%lu\n", data->user_frequency); > @@ -91,7 +91,7 @@ static int userspace_init(struct devfreq *devfreq) > goto out; > } > data->valid = false; > - devfreq->data = data; > + devfreq->governor_data = data; > > err = sysfs_create_group(&devfreq->dev.kobj, &dev_attr_group); > out: > @@ -107,8 +107,8 @@ static void userspace_exit(struct devfreq *devfreq) > if (devfreq->dev.kobj.sd) > sysfs_remove_group(&devfreq->dev.kobj, &dev_attr_group); > > - kfree(devfreq->data); > - devfreq->data = NULL; > + kfree(devfreq->governor_data); > + devfreq->governor_data = NULL; > } > > static int devfreq_userspace_handler(struct devfreq *devfreq, > diff --git a/include/linux/devfreq.h b/include/linux/devfreq.h > index 34aab4dd336c..4dc7cda4fd46 100644 > --- a/include/linux/devfreq.h > +++ b/include/linux/devfreq.h > @@ -152,8 +152,8 @@ struct devfreq_stats { > * @max_state: count of entry present in the frequency table. > * @previous_freq: previously configured frequency value. > * @last_status: devfreq user device info, performance statistics > - * @data: Private data of the governor. The devfreq framework does not > - * touch this. > + * @data: devfreq driver pass to governors, governor should not change it. > + * @governor_data: private data for governors, devfreq core doesn't touch it. > * @user_min_freq_req: PM QoS minimum frequency request from user (via sysfs) > * @user_max_freq_req: PM QoS maximum frequency request from user (via sysfs) > * @scaling_min_freq: Limit minimum frequency requested by OPP interface > @@ -193,7 +193,8 @@ struct devfreq { > unsigned long previous_freq; > struct devfreq_dev_status last_status; > > - void *data; /* private data for governors */ > + void *data; > + void *governor_data; > > struct dev_pm_qos_request user_min_freq_req; > struct dev_pm_qos_request user_max_freq_req;
On 10/22/2022 7:41 AM, Chanwoo Choi wrote: > Hi, > > Looks good to me. But, you need to send it to the stable mailing list > too as I commented on previous mail. > > Please add stable@vger.kernel.org to Cc. > Hi Chanwoo, Thanks for the notice. Please review this patch-v4 [1]. [1] https://lore.kernel.org/all/20221025072109.64025-1-kant@allwinnertech.com/
diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c index 63347a5ae599..8c5f6f7fca11 100644 --- a/drivers/devfreq/devfreq.c +++ b/drivers/devfreq/devfreq.c @@ -776,8 +776,7 @@ static void remove_sysfs_files(struct devfreq *devfreq, * @dev: the device to add devfreq feature. * @profile: device-specific profile to run devfreq. * @governor_name: name of the policy to choose frequency. - * @data: private data for the governor. The devfreq framework does not - * touch this value. + * @data: devfreq driver pass to governors, governor should not change it. */ struct devfreq *devfreq_add_device(struct device *dev, struct devfreq_dev_profile *profile, @@ -1011,8 +1010,7 @@ static void devm_devfreq_dev_release(struct device *dev, void *res) * @dev: the device to add devfreq feature. * @profile: device-specific profile to run devfreq. * @governor_name: name of the policy to choose frequency. - * @data: private data for the governor. The devfreq framework does not - * touch this value. + * @data: devfreq driver pass to governors, governor should not change it. * * This function manages automatically the memory of devfreq device using device * resource management and simplify the free operation for memory of devfreq diff --git a/drivers/devfreq/governor_userspace.c b/drivers/devfreq/governor_userspace.c index ab9db7adb3ad..d69672ccacc4 100644 --- a/drivers/devfreq/governor_userspace.c +++ b/drivers/devfreq/governor_userspace.c @@ -21,7 +21,7 @@ struct userspace_data { static int devfreq_userspace_func(struct devfreq *df, unsigned long *freq) { - struct userspace_data *data = df->data; + struct userspace_data *data = df->governor_data; if (data->valid) *freq = data->user_frequency; @@ -40,7 +40,7 @@ static ssize_t set_freq_store(struct device *dev, struct device_attribute *attr, int err = 0; mutex_lock(&devfreq->lock); - data = devfreq->data; + data = devfreq->governor_data; sscanf(buf, "%lu", &wanted); data->user_frequency = wanted; @@ -60,7 +60,7 @@ static ssize_t set_freq_show(struct device *dev, int err = 0; mutex_lock(&devfreq->lock); - data = devfreq->data; + data = devfreq->governor_data; if (data->valid) err = sprintf(buf, "%lu\n", data->user_frequency); @@ -91,7 +91,7 @@ static int userspace_init(struct devfreq *devfreq) goto out; } data->valid = false; - devfreq->data = data; + devfreq->governor_data = data; err = sysfs_create_group(&devfreq->dev.kobj, &dev_attr_group); out: @@ -107,8 +107,8 @@ static void userspace_exit(struct devfreq *devfreq) if (devfreq->dev.kobj.sd) sysfs_remove_group(&devfreq->dev.kobj, &dev_attr_group); - kfree(devfreq->data); - devfreq->data = NULL; + kfree(devfreq->governor_data); + devfreq->governor_data = NULL; } static int devfreq_userspace_handler(struct devfreq *devfreq, diff --git a/include/linux/devfreq.h b/include/linux/devfreq.h index 34aab4dd336c..4dc7cda4fd46 100644 --- a/include/linux/devfreq.h +++ b/include/linux/devfreq.h @@ -152,8 +152,8 @@ struct devfreq_stats { * @max_state: count of entry present in the frequency table. * @previous_freq: previously configured frequency value. * @last_status: devfreq user device info, performance statistics - * @data: Private data of the governor. The devfreq framework does not - * touch this. + * @data: devfreq driver pass to governors, governor should not change it. + * @governor_data: private data for governors, devfreq core doesn't touch it. * @user_min_freq_req: PM QoS minimum frequency request from user (via sysfs) * @user_max_freq_req: PM QoS maximum frequency request from user (via sysfs) * @scaling_min_freq: Limit minimum frequency requested by OPP interface @@ -193,7 +193,8 @@ struct devfreq { unsigned long previous_freq; struct devfreq_dev_status last_status; - void *data; /* private data for governors */ + void *data; + void *governor_data; struct dev_pm_qos_request user_min_freq_req; struct dev_pm_qos_request user_max_freq_req;
The member void *data in the structure devfreq can be overwrite by governor_userspace. For example: 1. The device driver assigned the devfreq governor to simple_ondemand by the function devfreq_add_device() and init the devfreq member void *data to a pointer of a static structure devfreq_simple_ondemand_data by the function devfreq_add_device(). 2. The user changed the devfreq governor to userspace by the command "echo userspace > /sys/class/devfreq/.../governor". 3. The governor userspace alloced a dynamic memory for the struct userspace_data and assigend the member void *data of devfreq to this memory by the function userspace_init(). 4. The user changed the devfreq governor back to simple_ondemand by the command "echo simple_ondemand > /sys/class/devfreq/.../governor". 5. The governor userspace exited and assigned the member void *data in the structure devfreq to NULL by the function userspace_exit(). 6. The governor simple_ondemand fetched the static information of devfreq_simple_ondemand_data in the function devfreq_simple_ondemand_func() but the member void *data of devfreq was assigned to NULL by the function userspace_exit(). 7. The information of upthreshold and downdifferential is lost and the governor simple_ondemand can't work correctly. The member void *data in the structure devfreq is designed for a static pointer used in a governor and inited by the function devfreq_add_device(). This patch add an element named governor_data in the devfreq structure which can be used by a governor(E.g userspace) who want to assign a private data to do some private things. Fixes: ce26c5bb9569 ("PM / devfreq: Add basic governors") Acked-by: MyungJoo Ham <myungjoo.ham@samsung.com> Signed-off-by: Kant Fan <kant@allwinnertech.com> --- drivers/devfreq/devfreq.c | 6 ++---- drivers/devfreq/governor_userspace.c | 12 ++++++------ include/linux/devfreq.h | 7 ++++--- 3 files changed, 12 insertions(+), 13 deletions(-)