diff options
| -rw-r--r-- | Documentation/locking/hwspinlock.rst | 57 | ||||
| -rw-r--r-- | drivers/hwspinlock/hwspinlock_core.c | 94 | ||||
| -rw-r--r-- | include/linux/hwspinlock.h | 18 |
3 files changed, 1 insertions, 168 deletions
diff --git a/Documentation/locking/hwspinlock.rst b/Documentation/locking/hwspinlock.rst index 2ffaa3cbd63f..a737c702a7d1 100644 --- a/Documentation/locking/hwspinlock.rst +++ b/Documentation/locking/hwspinlock.rst @@ -40,17 +40,6 @@ User API :: - struct hwspinlock *hwspin_lock_request(void); - -Dynamically assign an hwspinlock and return its address, or NULL -in case an unused hwspinlock isn't available. Users of this -API will usually want to communicate the lock's id to the remote core -before it can be used to achieve synchronization. - -Should be called from a process context (might sleep). - -:: - struct hwspinlock *hwspin_lock_request_specific(unsigned int id); Assign a specific hwspinlock id and return its address, or NULL @@ -312,17 +301,6 @@ The caller should **never** unlock an hwspinlock which is already unlocked. Doing so is considered a bug (there is no protection against this). This function will never sleep. -:: - - int hwspin_lock_get_id(struct hwspinlock *hwlock); - -Retrieve id number of a given hwspinlock. This is needed when an -hwspinlock is dynamically assigned: before it can be used to achieve -mutual exclusion with a remote cpu, the id number should be communicated -to the remote task with which we want to synchronize. - -Returns the hwspinlock id number, or -EINVAL if hwlock is null. - Typical usage ============= @@ -331,40 +309,7 @@ Typical usage #include <linux/hwspinlock.h> #include <linux/err.h> - int hwspinlock_example1(void) - { - struct hwspinlock *hwlock; - int ret; - - /* dynamically assign a hwspinlock */ - hwlock = hwspin_lock_request(); - if (!hwlock) - ... - - id = hwspin_lock_get_id(hwlock); - /* probably need to communicate id to a remote processor now */ - - /* take the lock, spin for 1 sec if it's already taken */ - ret = hwspin_lock_timeout(hwlock, 1000); - if (ret) - ... - - /* - * we took the lock, do our thing now, but do NOT sleep - */ - - /* release the lock */ - hwspin_unlock(hwlock); - - /* free the lock */ - ret = hwspin_lock_free(hwlock); - if (ret) - ... - - return ret; - } - - int hwspinlock_example2(void) + int hwspinlock_example(void) { struct hwspinlock *hwlock; int ret; diff --git a/drivers/hwspinlock/hwspinlock_core.c b/drivers/hwspinlock/hwspinlock_core.c index 6505261e6068..cc8e952a6772 100644 --- a/drivers/hwspinlock/hwspinlock_core.c +++ b/drivers/hwspinlock/hwspinlock_core.c @@ -710,66 +710,6 @@ static int __hwspin_lock_request(struct hwspinlock *hwlock) } /** - * hwspin_lock_get_id() - retrieve id number of a given hwspinlock - * @hwlock: a valid hwspinlock instance - * - * Returns: the id number of a given @hwlock, or -EINVAL if @hwlock is invalid. - */ -int hwspin_lock_get_id(struct hwspinlock *hwlock) -{ - if (!hwlock) { - pr_err("invalid hwlock\n"); - return -EINVAL; - } - - return hwlock_to_id(hwlock); -} -EXPORT_SYMBOL_GPL(hwspin_lock_get_id); - -/** - * hwspin_lock_request() - request an hwspinlock - * - * This function should be called by users of the hwspinlock device, - * in order to dynamically assign them an unused hwspinlock. - * Usually the user of this lock will then have to communicate the lock's id - * to the remote core before it can be used for synchronization (to get the - * id of a given hwlock, use hwspin_lock_get_id()). - * - * Should be called from a process context (might sleep) - * - * Returns: the address of the assigned hwspinlock, or %NULL on error - */ -struct hwspinlock *hwspin_lock_request(void) -{ - struct hwspinlock *hwlock; - int ret; - - mutex_lock(&hwspinlock_tree_lock); - - /* look for an unused lock */ - ret = radix_tree_gang_lookup_tag(&hwspinlock_tree, (void **)&hwlock, - 0, 1, HWSPINLOCK_UNUSED); - if (ret == 0) { - pr_warn("a free hwspinlock is not available\n"); - hwlock = NULL; - goto out; - } - - /* sanity check that should never fail */ - WARN_ON(ret > 1); - - /* mark as used and power up */ - ret = __hwspin_lock_request(hwlock); - if (ret < 0) - hwlock = NULL; - -out: - mutex_unlock(&hwspinlock_tree_lock); - return hwlock; -} -EXPORT_SYMBOL_GPL(hwspin_lock_request); - -/** * hwspin_lock_request_specific() - request for a specific hwspinlock * @id: index of the specific hwspinlock that is requested * @@ -913,40 +853,6 @@ int devm_hwspin_lock_free(struct device *dev, struct hwspinlock *hwlock) EXPORT_SYMBOL_GPL(devm_hwspin_lock_free); /** - * devm_hwspin_lock_request() - request an hwspinlock for a managed device - * @dev: the device to request an hwspinlock - * - * This function should be called by users of the hwspinlock device, - * in order to dynamically assign them an unused hwspinlock. - * Usually the user of this lock will then have to communicate the lock's id - * to the remote core before it can be used for synchronization (to get the - * id of a given hwlock, use hwspin_lock_get_id()). - * - * Should be called from a process context (might sleep) - * - * Returns: the address of the assigned hwspinlock, or %NULL on error - */ -struct hwspinlock *devm_hwspin_lock_request(struct device *dev) -{ - struct hwspinlock **ptr, *hwlock; - - ptr = devres_alloc(devm_hwspin_lock_release, sizeof(*ptr), GFP_KERNEL); - if (!ptr) - return NULL; - - hwlock = hwspin_lock_request(); - if (hwlock) { - *ptr = hwlock; - devres_add(dev, ptr); - } else { - devres_free(ptr); - } - - return hwlock; -} -EXPORT_SYMBOL_GPL(devm_hwspin_lock_request); - -/** * devm_hwspin_lock_request_specific() - request for a specific hwspinlock for * a managed device * @dev: the device to request the specific hwspinlock diff --git a/include/linux/hwspinlock.h b/include/linux/hwspinlock.h index f0231dbc4777..f35b42e8c5de 100644 --- a/include/linux/hwspinlock.h +++ b/include/linux/hwspinlock.h @@ -58,11 +58,9 @@ struct hwspinlock_pdata { int hwspin_lock_register(struct hwspinlock_device *bank, struct device *dev, const struct hwspinlock_ops *ops, int base_id, int num_locks); int hwspin_lock_unregister(struct hwspinlock_device *bank); -struct hwspinlock *hwspin_lock_request(void); struct hwspinlock *hwspin_lock_request_specific(unsigned int id); int hwspin_lock_free(struct hwspinlock *hwlock); int of_hwspin_lock_get_id(struct device_node *np, int index); -int hwspin_lock_get_id(struct hwspinlock *hwlock); int __hwspin_lock_timeout(struct hwspinlock *, unsigned int, int, unsigned long *); int __hwspin_trylock(struct hwspinlock *, int, unsigned long *); @@ -70,7 +68,6 @@ void __hwspin_unlock(struct hwspinlock *, int, unsigned long *); int of_hwspin_lock_get_id_byname(struct device_node *np, const char *name); int hwspin_lock_bust(struct hwspinlock *hwlock, unsigned int id); int devm_hwspin_lock_free(struct device *dev, struct hwspinlock *hwlock); -struct hwspinlock *devm_hwspin_lock_request(struct device *dev); struct hwspinlock *devm_hwspin_lock_request_specific(struct device *dev, unsigned int id); int devm_hwspin_lock_unregister(struct device *dev, @@ -95,11 +92,6 @@ int devm_hwspin_lock_register(struct device *dev, * Note: ERR_PTR(-ENODEV) will still be considered a success for NULL-checking * users. Others, which care, can still check this with IS_ERR. */ -static inline struct hwspinlock *hwspin_lock_request(void) -{ - return ERR_PTR(-ENODEV); -} - static inline struct hwspinlock *hwspin_lock_request_specific(unsigned int id) { return ERR_PTR(-ENODEV); @@ -138,11 +130,6 @@ static inline int of_hwspin_lock_get_id(struct device_node *np, int index) return 0; } -static inline int hwspin_lock_get_id(struct hwspinlock *hwlock) -{ - return 0; -} - static inline int of_hwspin_lock_get_id_byname(struct device_node *np, const char *name) { @@ -155,11 +142,6 @@ int devm_hwspin_lock_free(struct device *dev, struct hwspinlock *hwlock) return 0; } -static inline struct hwspinlock *devm_hwspin_lock_request(struct device *dev) -{ - return ERR_PTR(-ENODEV); -} - static inline struct hwspinlock *devm_hwspin_lock_request_specific(struct device *dev, unsigned int id) |