From 245bd6f6af8a62a2e2e14976e5ef3dc2b82ec153 Mon Sep 17 00:00:00 2001 From: Geert Uytterhoeven Date: Thu, 6 Nov 2014 15:51:00 +0200 Subject: PM / clock_ops: Add pm_clk_add_clk() The existing pm_clk_add() allows to pass a clock by con_id. However, when referring to a specific clock from DT, no con_id is available. Add pm_clk_add_clk(), which allows to specify the struct clk * directly. The will will increment refcount on clock pointer, so the caller has to use clk_put() on clock pointer when done. Reviewed-by: Santosh Shilimkar Reviewed-by: Kevin Hilman Signed-off-by: Geert Uytterhoeven Signed-off-by: Grygorii Strashko Reviewed-by: Dmitry Torokhov Signed-off-by: Rafael J. Wysocki --- drivers/base/power/clock_ops.c | 47 +++++++++++++++++++++++++++++++++--------- 1 file changed, 37 insertions(+), 10 deletions(-) (limited to 'drivers/base') diff --git a/drivers/base/power/clock_ops.c b/drivers/base/power/clock_ops.c index 78369305e069..f061eaa48bb5 100644 --- a/drivers/base/power/clock_ops.c +++ b/drivers/base/power/clock_ops.c @@ -12,6 +12,7 @@ #include #include #include +#include #include #include @@ -53,7 +54,8 @@ static inline int __pm_clk_enable(struct device *dev, struct clk *clk) */ static void pm_clk_acquire(struct device *dev, struct pm_clock_entry *ce) { - ce->clk = clk_get(dev, ce->con_id); + if (!ce->clk) + ce->clk = clk_get(dev, ce->con_id); if (IS_ERR(ce->clk)) { ce->status = PCE_STATUS_ERROR; } else { @@ -63,15 +65,8 @@ static void pm_clk_acquire(struct device *dev, struct pm_clock_entry *ce) } } -/** - * pm_clk_add - Start using a device clock for power management. - * @dev: Device whose clock is going to be used for power management. - * @con_id: Connection ID of the clock. - * - * Add the clock represented by @con_id to the list of clocks used for - * the power management of @dev. - */ -int pm_clk_add(struct device *dev, const char *con_id) +static int __pm_clk_add(struct device *dev, const char *con_id, + struct clk *clk) { struct pm_subsys_data *psd = dev_to_psd(dev); struct pm_clock_entry *ce; @@ -93,6 +88,12 @@ int pm_clk_add(struct device *dev, const char *con_id) kfree(ce); return -ENOMEM; } + } else { + if (IS_ERR(ce->clk) || !__clk_get(clk)) { + kfree(ce); + return -ENOENT; + } + ce->clk = clk; } pm_clk_acquire(dev, ce); @@ -103,6 +104,32 @@ int pm_clk_add(struct device *dev, const char *con_id) return 0; } +/** + * pm_clk_add - Start using a device clock for power management. + * @dev: Device whose clock is going to be used for power management. + * @con_id: Connection ID of the clock. + * + * Add the clock represented by @con_id to the list of clocks used for + * the power management of @dev. + */ +int pm_clk_add(struct device *dev, const char *con_id) +{ + return __pm_clk_add(dev, con_id, NULL); +} + +/** + * pm_clk_add_clk - Start using a device clock for power management. + * @dev: Device whose clock is going to be used for power management. + * @clk: Clock pointer + * + * Add the clock to the list of clocks used for the power management of @dev. + * It will increment refcount on clock pointer, use clk_put() on it when done. + */ +int pm_clk_add_clk(struct device *dev, struct clk *clk) +{ + return __pm_clk_add(dev, NULL, clk); +} + /** * __pm_clk_remove - Destroy PM clock entry. * @ce: PM clock entry to destroy. -- cgit v1.2.3 From 471f7707b6f0b18b6aa81119ed01525d9e712427 Mon Sep 17 00:00:00 2001 From: "Strashko, Grygorii" Date: Thu, 6 Nov 2014 15:51:01 +0200 Subject: PM / clock_ops: make __pm_clk_enable more generic Now there are two places in code which do the same things, so allow __pm_clk_enable() to accept pointer on pm_clock_entry structure as second parameter instead of pointer on clock and remove duplicated code. Also, updated function intended to be used by following patch. Signed-off-by: Grygorii Strashko Reviewed-by: Dmitry Torokhov Signed-off-by: Rafael J. Wysocki --- drivers/base/power/clock_ops.c | 38 ++++++++++++++++---------------------- 1 file changed, 16 insertions(+), 22 deletions(-) (limited to 'drivers/base') diff --git a/drivers/base/power/clock_ops.c b/drivers/base/power/clock_ops.c index f061eaa48bb5..b32b5d47b3c5 100644 --- a/drivers/base/power/clock_ops.c +++ b/drivers/base/power/clock_ops.c @@ -35,14 +35,20 @@ struct pm_clock_entry { /** * pm_clk_enable - Enable a clock, reporting any errors * @dev: The device for the given clock - * @clk: The clock being enabled. + * @ce: PM clock entry corresponding to the clock. */ -static inline int __pm_clk_enable(struct device *dev, struct clk *clk) +static inline int __pm_clk_enable(struct device *dev, struct pm_clock_entry *ce) { - int ret = clk_enable(clk); - if (ret) - dev_err(dev, "%s: failed to enable clk %p, error %d\n", - __func__, clk, ret); + int ret; + + if (ce->status < PCE_STATUS_ERROR) { + ret = clk_enable(ce->clk); + if (!ret) + ce->status = PCE_STATUS_ENABLED; + else + dev_err(dev, "%s: failed to enable clk %p, error %d\n", + __func__, ce->clk, ret); + } return ret; } @@ -293,7 +299,6 @@ int pm_clk_resume(struct device *dev) struct pm_subsys_data *psd = dev_to_psd(dev); struct pm_clock_entry *ce; unsigned long flags; - int ret; dev_dbg(dev, "%s()\n", __func__); @@ -302,13 +307,8 @@ int pm_clk_resume(struct device *dev) spin_lock_irqsave(&psd->lock, flags); - list_for_each_entry(ce, &psd->clock_list, node) { - if (ce->status < PCE_STATUS_ERROR) { - ret = __pm_clk_enable(dev, ce->clk); - if (!ret) - ce->status = PCE_STATUS_ENABLED; - } - } + list_for_each_entry(ce, &psd->clock_list, node) + __pm_clk_enable(dev, ce); spin_unlock_irqrestore(&psd->lock, flags); @@ -417,7 +417,6 @@ int pm_clk_resume(struct device *dev) struct pm_subsys_data *psd = dev_to_psd(dev); struct pm_clock_entry *ce; unsigned long flags; - int ret; dev_dbg(dev, "%s()\n", __func__); @@ -427,13 +426,8 @@ int pm_clk_resume(struct device *dev) spin_lock_irqsave(&psd->lock, flags); - list_for_each_entry(ce, &psd->clock_list, node) { - if (ce->status < PCE_STATUS_ERROR) { - ret = __pm_clk_enable(dev, ce->clk); - if (!ret) - ce->status = PCE_STATUS_ENABLED; - } - } + list_for_each_entry(ce, &psd->clock_list, node) + __pm_clk_enable(dev, ce); spin_unlock_irqrestore(&psd->lock, flags); -- cgit v1.2.3 From cd1a068a52ee6a3331a62fe53e87d6ca6cfd68a5 Mon Sep 17 00:00:00 2001 From: Viresh Kumar Date: Tue, 25 Nov 2014 16:04:16 +0530 Subject: PM / OPP rename 'head' as 'rcu_head' or 'srcu_head' based on its type Both 'struct dev_pm_opp' and 'struct device_opp' have member with name 'head' but with different types. This leads to confusion while reading the code. Name them 'rcu_head' and 'srcu_head'. Signed-off-by: Viresh Kumar Signed-off-by: Rafael J. Wysocki --- drivers/base/power/opp.c | 20 ++++++++++---------- 1 file changed, 10 insertions(+), 10 deletions(-) (limited to 'drivers/base') diff --git a/drivers/base/power/opp.c b/drivers/base/power/opp.c index 89ced955fafa..76ae6fd28345 100644 --- a/drivers/base/power/opp.c +++ b/drivers/base/power/opp.c @@ -53,7 +53,7 @@ * @rate: Frequency in hertz * @u_volt: Nominal voltage in microvolts corresponding to this OPP * @dev_opp: points back to the device_opp struct this opp belongs to - * @head: RCU callback head used for deferred freeing + * @rcu_head: RCU callback head used for deferred freeing * * This structure stores the OPP information for a given device. */ @@ -65,7 +65,7 @@ struct dev_pm_opp { unsigned long u_volt; struct device_opp *dev_opp; - struct rcu_head head; + struct rcu_head rcu_head; }; /** @@ -76,7 +76,7 @@ struct dev_pm_opp { * RCU usage: nodes are not modified in the list of device_opp, * however addition is possible and is secured by dev_opp_list_lock * @dev: device pointer - * @head: notifier head to notify the OPP availability changes. + * @srcu_head: notifier head to notify the OPP availability changes. * @opp_list: list of opps * * This is an internal data structure maintaining the link to opps attached to @@ -87,7 +87,7 @@ struct device_opp { struct list_head node; struct device *dev; - struct srcu_notifier_head head; + struct srcu_notifier_head srcu_head; struct list_head opp_list; }; @@ -436,7 +436,7 @@ int dev_pm_opp_add(struct device *dev, unsigned long freq, unsigned long u_volt) } dev_opp->dev = dev; - srcu_init_notifier_head(&dev_opp->head); + srcu_init_notifier_head(&dev_opp->srcu_head); INIT_LIST_HEAD(&dev_opp->opp_list); /* Secure the device list modification */ @@ -481,7 +481,7 @@ int dev_pm_opp_add(struct device *dev, unsigned long freq, unsigned long u_volt) * Notify the changes in the availability of the operable * frequency/voltage list. */ - srcu_notifier_call_chain(&dev_opp->head, OPP_EVENT_ADD, new_opp); + srcu_notifier_call_chain(&dev_opp->srcu_head, OPP_EVENT_ADD, new_opp); return 0; } EXPORT_SYMBOL_GPL(dev_pm_opp_add); @@ -557,14 +557,14 @@ static int opp_set_availability(struct device *dev, unsigned long freq, list_replace_rcu(&opp->node, &new_opp->node); mutex_unlock(&dev_opp_list_lock); - kfree_rcu(opp, head); + kfree_rcu(opp, rcu_head); /* Notify the change of the OPP availability */ if (availability_req) - srcu_notifier_call_chain(&dev_opp->head, OPP_EVENT_ENABLE, + srcu_notifier_call_chain(&dev_opp->srcu_head, OPP_EVENT_ENABLE, new_opp); else - srcu_notifier_call_chain(&dev_opp->head, OPP_EVENT_DISABLE, + srcu_notifier_call_chain(&dev_opp->srcu_head, OPP_EVENT_DISABLE, new_opp); return 0; @@ -629,7 +629,7 @@ struct srcu_notifier_head *dev_pm_opp_get_notifier(struct device *dev) if (IS_ERR(dev_opp)) return ERR_CAST(dev_opp); /* matching type */ - return &dev_opp->head; + return &dev_opp->srcu_head; } #ifdef CONFIG_OF -- cgit v1.2.3 From a7470db6fec481b14afea117846fce383671ba59 Mon Sep 17 00:00:00 2001 From: Viresh Kumar Date: Tue, 25 Nov 2014 16:04:17 +0530 Subject: PM / OPP don't match for existing OPPs when list is empty OPP list is guaranteed to be empty when 'dev_opp' is created. And so we don't need to run the comparison loop with existing OPPs. Signed-off-by: Viresh Kumar Signed-off-by: Rafael J. Wysocki --- drivers/base/power/opp.c | 15 +++++++++------ 1 file changed, 9 insertions(+), 6 deletions(-) (limited to 'drivers/base') diff --git a/drivers/base/power/opp.c b/drivers/base/power/opp.c index 76ae6fd28345..a333e2ef5cb2 100644 --- a/drivers/base/power/opp.c +++ b/drivers/base/power/opp.c @@ -417,6 +417,12 @@ int dev_pm_opp_add(struct device *dev, unsigned long freq, unsigned long u_volt) /* Hold our list modification lock here */ mutex_lock(&dev_opp_list_lock); + /* populate the opp table */ + new_opp->dev_opp = dev_opp; + new_opp->rate = freq; + new_opp->u_volt = u_volt; + new_opp->available = true; + /* Check for existing list for 'dev' */ dev_opp = find_device_opp(dev); if (IS_ERR(dev_opp)) { @@ -441,14 +447,10 @@ int dev_pm_opp_add(struct device *dev, unsigned long freq, unsigned long u_volt) /* Secure the device list modification */ list_add_rcu(&dev_opp->node, &dev_opp_list); + head = &dev_opp->opp_list; + goto list_add; } - /* populate the opp table */ - new_opp->dev_opp = dev_opp; - new_opp->rate = freq; - new_opp->u_volt = u_volt; - new_opp->available = true; - /* * Insert new OPP in order of increasing frequency * and discard if already present @@ -474,6 +476,7 @@ int dev_pm_opp_add(struct device *dev, unsigned long freq, unsigned long u_volt) return ret; } +list_add: list_add_rcu(&new_opp->node, head); mutex_unlock(&dev_opp_list_lock); -- cgit v1.2.3 From 38393409da345cd48d94a0e74c7bbc3402742882 Mon Sep 17 00:00:00 2001 From: Viresh Kumar Date: Tue, 25 Nov 2014 16:04:18 +0530 Subject: PM / OPP mark OPPs as 'static' or 'dynamic' Static OPPs are the ones created from Device Tree entries and dynamic are the ones created at runtime by calling dev_pm_opp_add(). There is a need to distinguish them as we need to free static OPPs from cpufreq drivers when they are removed. So, add another field 'dynamic' in 'struct dev_pm_opp' to keep this information. Signed-off-by: Viresh Kumar Signed-off-by: Rafael J. Wysocki --- drivers/base/power/opp.c | 59 ++++++++++++++++++++++++++++-------------------- 1 file changed, 34 insertions(+), 25 deletions(-) (limited to 'drivers/base') diff --git a/drivers/base/power/opp.c b/drivers/base/power/opp.c index a333e2ef5cb2..b249b0127eff 100644 --- a/drivers/base/power/opp.c +++ b/drivers/base/power/opp.c @@ -49,6 +49,7 @@ * are protected by the dev_opp_list_lock for integrity. * IMPORTANT: the opp nodes should be maintained in increasing * order. + * @dynamic: not-created from static DT entries. * @available: true/false - marks if this OPP as available or not * @rate: Frequency in hertz * @u_volt: Nominal voltage in microvolts corresponding to this OPP @@ -61,6 +62,7 @@ struct dev_pm_opp { struct list_head node; bool available; + bool dynamic; unsigned long rate; unsigned long u_volt; @@ -378,30 +380,8 @@ struct dev_pm_opp *dev_pm_opp_find_freq_floor(struct device *dev, } EXPORT_SYMBOL_GPL(dev_pm_opp_find_freq_floor); -/** - * dev_pm_opp_add() - Add an OPP table from a table definitions - * @dev: device for which we do this operation - * @freq: Frequency in Hz for this OPP - * @u_volt: Voltage in uVolts for this OPP - * - * This function adds an opp definition to the opp list and returns status. - * The opp is made available by default and it can be controlled using - * dev_pm_opp_enable/disable functions. - * - * Locking: The internal device_opp and opp structures are RCU protected. - * Hence this function internally uses RCU updater strategy with mutex locks - * to keep the integrity of the internal data structures. Callers should ensure - * that this function is *NOT* called under RCU protection or in contexts where - * mutex cannot be locked. - * - * Return: - * 0: On success OR - * Duplicate OPPs (both freq and volt are same) and opp->available - * -EEXIST: Freq are same and volt are different OR - * Duplicate OPPs (both freq and volt are same) and !opp->available - * -ENOMEM: Memory allocation failure - */ -int dev_pm_opp_add(struct device *dev, unsigned long freq, unsigned long u_volt) +static int dev_pm_opp_add_dynamic(struct device *dev, unsigned long freq, + unsigned long u_volt, bool dynamic) { struct device_opp *dev_opp = NULL; struct dev_pm_opp *opp, *new_opp; @@ -422,6 +402,7 @@ int dev_pm_opp_add(struct device *dev, unsigned long freq, unsigned long u_volt) new_opp->rate = freq; new_opp->u_volt = u_volt; new_opp->available = true; + new_opp->dynamic = dynamic; /* Check for existing list for 'dev' */ dev_opp = find_device_opp(dev); @@ -487,6 +468,34 @@ list_add: srcu_notifier_call_chain(&dev_opp->srcu_head, OPP_EVENT_ADD, new_opp); return 0; } + +/** + * dev_pm_opp_add() - Add an OPP table from a table definitions + * @dev: device for which we do this operation + * @freq: Frequency in Hz for this OPP + * @u_volt: Voltage in uVolts for this OPP + * + * This function adds an opp definition to the opp list and returns status. + * The opp is made available by default and it can be controlled using + * dev_pm_opp_enable/disable functions. + * + * Locking: The internal device_opp and opp structures are RCU protected. + * Hence this function internally uses RCU updater strategy with mutex locks + * to keep the integrity of the internal data structures. Callers should ensure + * that this function is *NOT* called under RCU protection or in contexts where + * mutex cannot be locked. + * + * Return: + * 0: On success OR + * Duplicate OPPs (both freq and volt are same) and opp->available + * -EEXIST: Freq are same and volt are different OR + * Duplicate OPPs (both freq and volt are same) and !opp->available + * -ENOMEM: Memory allocation failure + */ +int dev_pm_opp_add(struct device *dev, unsigned long freq, unsigned long u_volt) +{ + return dev_pm_opp_add_dynamic(dev, freq, u_volt, true); +} EXPORT_SYMBOL_GPL(dev_pm_opp_add); /** @@ -669,7 +678,7 @@ int of_init_opp_table(struct device *dev) unsigned long freq = be32_to_cpup(val++) * 1000; unsigned long volt = be32_to_cpup(val++); - if (dev_pm_opp_add(dev, freq, volt)) + if (dev_pm_opp_add_dynamic(dev, freq, volt, false)) dev_warn(dev, "%s: Failed to add OPP %ld\n", __func__, freq); nr -= 2; -- cgit v1.2.3 From 129eec55df6ab1b5ecdd89fd7db7a2cd103200b5 Mon Sep 17 00:00:00 2001 From: Viresh Kumar Date: Thu, 27 Nov 2014 08:54:06 +0530 Subject: PM / OPP Introduce APIs to remove OPPs OPPs are created statically (from DT) or dynamically. Currently we don't free OPPs that are created statically, when the module unloads. And so if the module is inserted back again, we get warning for duplicate OPPs as the same were already present. Also, there might be a need to remove dynamic OPPs in future and so API for that is also added. This patch adds helper APIs to remove/free existing static and dynamic OPPs. Because the OPPs are used both under RCU and SRCU, we have to wait for grace period of both. And so are using kfree_rcu() from within call_srcu(). Signed-off-by: Viresh Kumar Signed-off-by: Rafael J. Wysocki --- drivers/base/power/opp.c | 102 +++++++++++++++++++++++++++++++++++++++++++++++ include/linux/pm_opp.h | 12 +++++- 2 files changed, 113 insertions(+), 1 deletion(-) (limited to 'drivers/base') diff --git a/drivers/base/power/opp.c b/drivers/base/power/opp.c index b249b0127eff..977474a3c64f 100644 --- a/drivers/base/power/opp.c +++ b/drivers/base/power/opp.c @@ -79,6 +79,7 @@ struct dev_pm_opp { * however addition is possible and is secured by dev_opp_list_lock * @dev: device pointer * @srcu_head: notifier head to notify the OPP availability changes. + * @rcu_head: RCU callback head used for deferred freeing * @opp_list: list of opps * * This is an internal data structure maintaining the link to opps attached to @@ -90,6 +91,7 @@ struct device_opp { struct device *dev; struct srcu_notifier_head srcu_head; + struct rcu_head rcu_head; struct list_head opp_list; }; @@ -498,6 +500,76 @@ int dev_pm_opp_add(struct device *dev, unsigned long freq, unsigned long u_volt) } EXPORT_SYMBOL_GPL(dev_pm_opp_add); +static void kfree_opp_rcu(struct rcu_head *head) +{ + struct dev_pm_opp *opp = container_of(head, struct dev_pm_opp, rcu_head); + + kfree_rcu(opp, rcu_head); +} + +static void kfree_device_rcu(struct rcu_head *head) +{ + struct device_opp *device_opp = container_of(head, struct device_opp, rcu_head); + + kfree(device_opp); +} + +void __dev_pm_opp_remove(struct device_opp *dev_opp, struct dev_pm_opp *opp) +{ + /* + * Notify the changes in the availability of the operable + * frequency/voltage list. + */ + srcu_notifier_call_chain(&dev_opp->srcu_head, OPP_EVENT_REMOVE, opp); + list_del_rcu(&opp->node); + call_srcu(&dev_opp->srcu_head.srcu, &opp->rcu_head, kfree_opp_rcu); + + if (list_empty(&dev_opp->opp_list)) { + list_del_rcu(&dev_opp->node); + call_srcu(&dev_opp->srcu_head.srcu, &dev_opp->rcu_head, + kfree_device_rcu); + } +} + +/** + * dev_pm_opp_remove() - Remove an OPP from OPP list + * @dev: device for which we do this operation + * @freq: OPP to remove with matching 'freq' + * + * This function removes an opp from the opp list. + */ +void dev_pm_opp_remove(struct device *dev, unsigned long freq) +{ + struct dev_pm_opp *opp; + struct device_opp *dev_opp; + bool found = false; + + /* Hold our list modification lock here */ + mutex_lock(&dev_opp_list_lock); + + dev_opp = find_device_opp(dev); + if (IS_ERR(dev_opp)) + goto unlock; + + list_for_each_entry(opp, &dev_opp->opp_list, node) { + if (opp->rate == freq) { + found = true; + break; + } + } + + if (!found) { + dev_warn(dev, "%s: Couldn't find OPP with freq: %lu\n", + __func__, freq); + goto unlock; + } + + __dev_pm_opp_remove(dev_opp, opp); +unlock: + mutex_unlock(&dev_opp_list_lock); +} +EXPORT_SYMBOL_GPL(dev_pm_opp_remove); + /** * opp_set_availability() - helper to set the availability of an opp * @dev: device for which we do this operation @@ -687,4 +759,34 @@ int of_init_opp_table(struct device *dev) return 0; } EXPORT_SYMBOL_GPL(of_init_opp_table); + +/** + * of_free_opp_table() - Free OPP table entries created from static DT entries + * @dev: device pointer used to lookup device OPPs. + * + * Free OPPs created using static entries present in DT. + */ +void of_free_opp_table(struct device *dev) +{ + struct device_opp *dev_opp = find_device_opp(dev); + struct dev_pm_opp *opp, *tmp; + + /* Check for existing list for 'dev' */ + dev_opp = find_device_opp(dev); + if (WARN(IS_ERR(dev_opp), "%s: dev_opp: %ld\n", dev_name(dev), + PTR_ERR(dev_opp))) + return; + + /* Hold our list modification lock here */ + mutex_lock(&dev_opp_list_lock); + + /* Free static OPPs */ + list_for_each_entry_safe(opp, tmp, &dev_opp->opp_list, node) { + if (!opp->dynamic) + __dev_pm_opp_remove(dev_opp, opp); + } + + mutex_unlock(&dev_opp_list_lock); +} +EXPORT_SYMBOL_GPL(of_free_opp_table); #endif diff --git a/include/linux/pm_opp.h b/include/linux/pm_opp.h index 0330217abfad..cec2d4540914 100644 --- a/include/linux/pm_opp.h +++ b/include/linux/pm_opp.h @@ -21,7 +21,7 @@ struct dev_pm_opp; struct device; enum dev_pm_opp_event { - OPP_EVENT_ADD, OPP_EVENT_ENABLE, OPP_EVENT_DISABLE, + OPP_EVENT_ADD, OPP_EVENT_REMOVE, OPP_EVENT_ENABLE, OPP_EVENT_DISABLE, }; #if defined(CONFIG_PM_OPP) @@ -44,6 +44,7 @@ struct dev_pm_opp *dev_pm_opp_find_freq_ceil(struct device *dev, int dev_pm_opp_add(struct device *dev, unsigned long freq, unsigned long u_volt); +void dev_pm_opp_remove(struct device *dev, unsigned long freq); int dev_pm_opp_enable(struct device *dev, unsigned long freq); @@ -90,6 +91,10 @@ static inline int dev_pm_opp_add(struct device *dev, unsigned long freq, return -EINVAL; } +static inline void dev_pm_opp_remove(struct device *dev, unsigned long freq) +{ +} + static inline int dev_pm_opp_enable(struct device *dev, unsigned long freq) { return 0; @@ -109,11 +114,16 @@ static inline struct srcu_notifier_head *dev_pm_opp_get_notifier( #if defined(CONFIG_PM_OPP) && defined(CONFIG_OF) int of_init_opp_table(struct device *dev); +void of_free_opp_table(struct device *dev); #else static inline int of_init_opp_table(struct device *dev) { return -EINVAL; } + +static inline void of_free_opp_table(struct device *dev) +{ +} #endif #endif /* __LINUX_OPP_H__ */ -- cgit v1.2.3 From b4037aaa584bd914bbf578f5ceb2d9884fa7ddb6 Mon Sep 17 00:00:00 2001 From: Viresh Kumar Date: Thu, 27 Nov 2014 08:54:07 +0530 Subject: PM / OPP replace kfree_rcu() with call_srcu() in opp_set_availability() This existed before we introduced call_srcu() in opp layer to synchronize with srcu_notifier_call_chain() while removing OPPs. And is a potential bug which wasn't noticed earlier. Let fix it as well by using the right API to free OPP. Signed-off-by: Viresh Kumar Signed-off-by: Rafael J. Wysocki --- drivers/base/power/opp.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/base') diff --git a/drivers/base/power/opp.c b/drivers/base/power/opp.c index 977474a3c64f..2d195f3a1998 100644 --- a/drivers/base/power/opp.c +++ b/drivers/base/power/opp.c @@ -641,7 +641,7 @@ static int opp_set_availability(struct device *dev, unsigned long freq, list_replace_rcu(&opp->node, &new_opp->node); mutex_unlock(&dev_opp_list_lock); - kfree_rcu(opp, rcu_head); + call_srcu(&dev_opp->srcu_head.srcu, &opp->rcu_head, kfree_opp_rcu); /* Notify the change of the OPP availability */ if (availability_req) -- cgit v1.2.3