From 585fc83ece43be63d5775e536f855db33dd752cf Mon Sep 17 00:00:00 2001 From: Chanwoo Choi Date: Fri, 9 May 2014 16:43:07 +0900 Subject: PM / devfreq: Fix devfreq_remove_device() to improve the sequence of resource free This patch modify devfreq_remove_device() to improve the sequence of resource free. If executing existing devfreq_remove_device(), this function always executes _remove_devfreq() twice. In result, second _remove_devfreq() always return error value. So, This patch resolves complicated function sequence as following: [Flow sequence before modification] devfreq_remove_device() _remove_devfreq(devfreq, false) kfree(devfreq); /* Free devfreq */ if (!skip ...) { /* skip is false */ device_unregister(&devfreq->dev) put_device(&devfreq->dev); ... dev->release() devfreq_dev_release() _remove_devfreq(devfreq, true) <- Recall to free devfreq /* * Always return error without freeing resource because * already _remove_devfreq() frees the memory of devfreq. */ } [Flow sequence after modification] devfreq_remove_device device_unregister(&devfreq->dev) put_device(&devfreq->dev); .. dev->release() devfreq_dev_release() _remove_devfreq() kfree(devfreq); /* Free devfreq */ Signed-off-by: Chanwoo Choi [Merge conflict resolved by MyungJoo] Signed-off-by: MyungJoo Ham --- drivers/devfreq/devfreq.c | 14 ++++---------- 1 file changed, 4 insertions(+), 10 deletions(-) (limited to 'drivers/devfreq/devfreq.c') diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c index 2042ec3656b..af4af770857 100644 --- a/drivers/devfreq/devfreq.c +++ b/drivers/devfreq/devfreq.c @@ -394,7 +394,7 @@ static int devfreq_notifier_call(struct notifier_block *nb, unsigned long type, * @devfreq: the devfreq struct * @skip: skip calling device_unregister(). */ -static void _remove_devfreq(struct devfreq *devfreq, bool skip) +static void _remove_devfreq(struct devfreq *devfreq) { mutex_lock(&devfreq_list_lock); if (IS_ERR(find_device_devfreq(devfreq->dev.parent))) { @@ -412,11 +412,6 @@ static void _remove_devfreq(struct devfreq *devfreq, bool skip) if (devfreq->profile->exit) devfreq->profile->exit(devfreq->dev.parent); - if (!skip && get_device(&devfreq->dev)) { - device_unregister(&devfreq->dev); - put_device(&devfreq->dev); - } - mutex_destroy(&devfreq->lock); kfree(devfreq); } @@ -426,14 +421,12 @@ static void _remove_devfreq(struct devfreq *devfreq, bool skip) * @dev: the devfreq device * * This calls _remove_devfreq() if _remove_devfreq() is not called. - * Note that devfreq_dev_release() could be called by _remove_devfreq() as - * well as by others unregistering the device. */ static void devfreq_dev_release(struct device *dev) { struct devfreq *devfreq = to_devfreq(dev); - _remove_devfreq(devfreq, true); + _remove_devfreq(devfreq); } /** @@ -544,7 +537,8 @@ int devfreq_remove_device(struct devfreq *devfreq) if (!devfreq) return -EINVAL; - _remove_devfreq(devfreq, false); + device_unregister(&devfreq->dev); + put_device(&devfreq->dev); return 0; } -- cgit v1.2.3-70-g09d2 From 8cd84092d35e52372da2c3c3c2afb1a719917af2 Mon Sep 17 00:00:00 2001 From: Chanwoo Choi Date: Fri, 9 May 2014 16:43:08 +0900 Subject: PM / devfreq: Add resource-managed function for devfreq device This patch add resource-managed function for devfreq device as following functions. The devm_devfreq_add_device() manages automatically the memory of devfreq device using device resource management. - devm_devfreq_add_device() - devm_devfreq_remove_device() Signed-off-by: Chanwoo Choi Signed-off-by: MyungJoo Ham --- drivers/devfreq/devfreq.c | 63 +++++++++++++++++++++++++++++++++++++++++++++++ include/linux/devfreq.h | 21 +++++++++++++++- 2 files changed, 83 insertions(+), 1 deletion(-) (limited to 'drivers/devfreq/devfreq.c') diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c index af4af770857..8b6295d9d1f 100644 --- a/drivers/devfreq/devfreq.c +++ b/drivers/devfreq/devfreq.c @@ -544,6 +544,69 @@ int devfreq_remove_device(struct devfreq *devfreq) } EXPORT_SYMBOL(devfreq_remove_device); +static int devm_devfreq_dev_match(struct device *dev, void *res, void *data) +{ + struct devfreq **r = res; + + if (WARN_ON(!r || !*r)) + return 0; + + return *r == data; +} + +static void devm_devfreq_dev_release(struct device *dev, void *res) +{ + devfreq_remove_device(*(struct devfreq **)res); +} + +/** + * devm_devfreq_add_device() - Resource-managed devfreq_add_device() + * @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. + * + * This function manages automatically the memory of devfreq device using device + * resource management and simplify the free operation for memory of devfreq + * device. + */ +struct devfreq *devm_devfreq_add_device(struct device *dev, + struct devfreq_dev_profile *profile, + const char *governor_name, + void *data) +{ + struct devfreq **ptr, *devfreq; + + ptr = devres_alloc(devm_devfreq_dev_release, sizeof(*ptr), GFP_KERNEL); + if (!ptr) + return ERR_PTR(-ENOMEM); + + devfreq = devfreq_add_device(dev, profile, governor_name, data); + if (IS_ERR(devfreq)) { + devres_free(ptr); + return ERR_PTR(-ENOMEM); + } + + *ptr = devfreq; + devres_add(dev, ptr); + + return devfreq; +} +EXPORT_SYMBOL(devm_devfreq_add_device); + +/** + * devm_devfreq_remove_device() - Resource-managed devfreq_remove_device() + * @dev: the device to add devfreq feature. + * @devfreq: the devfreq instance to be removed + */ +void devm_devfreq_remove_device(struct device *dev, struct devfreq *devfreq) +{ + WARN_ON(devres_release(dev, devm_devfreq_dev_release, + devm_devfreq_dev_match, devfreq)); +} +EXPORT_SYMBOL(devm_devfreq_remove_device); + /** * devfreq_suspend_device() - Suspend devfreq of a device. * @devfreq: the devfreq instance to be suspended diff --git a/include/linux/devfreq.h b/include/linux/devfreq.h index d48dc00232a..023d668a2cb 100644 --- a/include/linux/devfreq.h +++ b/include/linux/devfreq.h @@ -181,6 +181,12 @@ extern struct devfreq *devfreq_add_device(struct device *dev, const char *governor_name, void *data); extern int devfreq_remove_device(struct devfreq *devfreq); +extern struct devfreq *devm_devfreq_add_device(struct device *dev, + struct devfreq_dev_profile *profile, + const char *governor_name, + void *data); +extern void devm_devfreq_remove_device(struct device *dev, + struct devfreq *devfreq); /* Supposed to be called by PM_SLEEP/PM_RUNTIME callbacks */ extern int devfreq_suspend_device(struct devfreq *devfreq); @@ -220,7 +226,7 @@ static inline struct devfreq *devfreq_add_device(struct device *dev, const char *governor_name, void *data) { - return NULL; + return ERR_PTR(-ENOSYS); } static inline int devfreq_remove_device(struct devfreq *devfreq) @@ -228,6 +234,19 @@ static inline int devfreq_remove_device(struct devfreq *devfreq) return 0; } +static inline struct devfreq *devm_devfreq_add_device(struct device *dev, + struct devfreq_dev_profile *profile, + const char *governor_name, + void *data) +{ + return ERR_PTR(-ENOSYS); +} + +static inline void devm_devfreq_remove_device(struct device *dev, + struct devfreq *devfreq) +{ +} + static inline int devfreq_suspend_device(struct devfreq *devfreq) { return 0; -- cgit v1.2.3-70-g09d2 From d5b040d0cab9cae1dc1ad61a07019062235f4878 Mon Sep 17 00:00:00 2001 From: Chanwoo Choi Date: Fri, 9 May 2014 16:43:09 +0900 Subject: PM / devfreq: Add devm_devfreq_{register,unregister}_opp_notfier function This patch add resource-managed function for devfreq opp as following functions. The devm_devfreq_register_opp_notifier() manages automatically the registration of devfreq opp using device resource management. - devm_devfreq_register_opp_notifier - devm_devfreq_unregister_opp_notifier() Signed-off-by: Chanwoo Choi Signed-off-by: MyungJoo Ham --- drivers/devfreq/devfreq.c | 48 +++++++++++++++++++++++++++++++++++++++++++++++ include/linux/devfreq.h | 14 ++++++++++++++ 2 files changed, 62 insertions(+) (limited to 'drivers/devfreq/devfreq.c') diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c index 8b6295d9d1f..9f90369dd6b 100644 --- a/drivers/devfreq/devfreq.c +++ b/drivers/devfreq/devfreq.c @@ -1169,6 +1169,54 @@ int devfreq_unregister_opp_notifier(struct device *dev, struct devfreq *devfreq) return ret; } +static void devm_devfreq_opp_release(struct device *dev, void *res) +{ + devfreq_unregister_opp_notifier(dev, *(struct devfreq **)res); +} + +/** + * devm_ devfreq_register_opp_notifier() + * - Resource-managed devfreq_register_opp_notifier() + * @dev: The devfreq user device. (parent of devfreq) + * @devfreq: The devfreq object. + */ +int devm_devfreq_register_opp_notifier(struct device *dev, + struct devfreq *devfreq) +{ + struct devfreq **ptr; + int ret; + + ptr = devres_alloc(devm_devfreq_opp_release, sizeof(*ptr), GFP_KERNEL); + if (!ptr) + return -ENOMEM; + + ret = devfreq_register_opp_notifier(dev, devfreq); + if (ret) { + devres_free(ptr); + return ret; + } + + *ptr = devfreq; + devres_add(dev, ptr); + + return 0; +} +EXPORT_SYMBOL(devm_devfreq_register_opp_notifier); + +/** + * devm_devfreq_unregister_opp_notifier() + * - Resource-managed devfreq_unregister_opp_notifier() + * @dev: The devfreq user device. (parent of devfreq) + * @devfreq: The devfreq object. + */ +void devm_devfreq_unregister_opp_notifier(struct device *dev, + struct devfreq *devfreq) +{ + WARN_ON(devres_release(dev, devm_devfreq_opp_release, + devm_devfreq_dev_match, devfreq)); +} +EXPORT_SYMBOL(devm_devfreq_unregister_opp_notifier); + MODULE_AUTHOR("MyungJoo Ham "); MODULE_DESCRIPTION("devfreq class support"); MODULE_LICENSE("GPL"); diff --git a/include/linux/devfreq.h b/include/linux/devfreq.h index 023d668a2cb..f1863dcd83e 100644 --- a/include/linux/devfreq.h +++ b/include/linux/devfreq.h @@ -199,6 +199,10 @@ extern int devfreq_register_opp_notifier(struct device *dev, struct devfreq *devfreq); extern int devfreq_unregister_opp_notifier(struct device *dev, struct devfreq *devfreq); +extern int devm_devfreq_register_opp_notifier(struct device *dev, + struct devfreq *devfreq); +extern void devm_devfreq_unregister_opp_notifier(struct device *dev, + struct devfreq *devfreq); #if IS_ENABLED(CONFIG_DEVFREQ_GOV_SIMPLE_ONDEMAND) /** @@ -275,6 +279,16 @@ static inline int devfreq_unregister_opp_notifier(struct device *dev, return -EINVAL; } +static inline int devm_devfreq_register_opp_notifier(struct device *dev, + struct devfreq *devfreq) +{ + return -EINVAL; +} + +static inline void devm_devfreq_unregister_opp_notifier(struct device *dev, + struct devfreq *devfreq) +{ +} #endif /* CONFIG_PM_DEVFREQ */ #endif /* __LINUX_DEVFREQ_H__ */ -- cgit v1.2.3-70-g09d2