From e8db0be1245de16a6cc6365506abc392c3c212d4 Mon Sep 17 00:00:00 2001 From: Jean Pihet Date: Thu, 25 Aug 2011 15:35:03 +0200 Subject: PM QoS: Move and rename the implementation files The PM QoS implementation files are better named kernel/power/qos.c and include/linux/pm_qos.h. The PM QoS support is compiled under the CONFIG_PM option. Signed-off-by: Jean Pihet Acked-by: markgross Reviewed-by: Kevin Hilman Signed-off-by: Rafael J. Wysocki --- kernel/Makefile | 2 +- kernel/pm_qos_params.c | 481 ------------------------------------------------- kernel/power/Makefile | 2 +- kernel/power/qos.c | 481 +++++++++++++++++++++++++++++++++++++++++++++++++ 4 files changed, 483 insertions(+), 483 deletions(-) delete mode 100644 kernel/pm_qos_params.c create mode 100644 kernel/power/qos.c (limited to 'kernel') diff --git a/kernel/Makefile b/kernel/Makefile index eca595e2fd5..2da48d3515e 100644 --- a/kernel/Makefile +++ b/kernel/Makefile @@ -9,7 +9,7 @@ obj-y = sched.o fork.o exec_domain.o panic.o printk.o \ rcupdate.o extable.o params.o posix-timers.o \ kthread.o wait.o kfifo.o sys_ni.o posix-cpu-timers.o mutex.o \ hrtimer.o rwsem.o nsproxy.o srcu.o semaphore.o \ - notifier.o ksysfs.o pm_qos_params.o sched_clock.o cred.o \ + notifier.o ksysfs.o sched_clock.o cred.o \ async.o range.o obj-y += groups.o diff --git a/kernel/pm_qos_params.c b/kernel/pm_qos_params.c deleted file mode 100644 index 37f05d0f079..00000000000 --- a/kernel/pm_qos_params.c +++ /dev/null @@ -1,481 +0,0 @@ -/* - * This module exposes the interface to kernel space for specifying - * QoS dependencies. It provides infrastructure for registration of: - * - * Dependents on a QoS value : register requests - * Watchers of QoS value : get notified when target QoS value changes - * - * This QoS design is best effort based. Dependents register their QoS needs. - * Watchers register to keep track of the current QoS needs of the system. - * - * There are 3 basic classes of QoS parameter: latency, timeout, throughput - * each have defined units: - * latency: usec - * timeout: usec <-- currently not used. - * throughput: kbs (kilo byte / sec) - * - * There are lists of pm_qos_objects each one wrapping requests, notifiers - * - * User mode requests on a QOS parameter register themselves to the - * subsystem by opening the device node /dev/... and writing there request to - * the node. As long as the process holds a file handle open to the node the - * client continues to be accounted for. Upon file release the usermode - * request is removed and a new qos target is computed. This way when the - * request that the application has is cleaned up when closes the file - * pointer or exits the pm_qos_object will get an opportunity to clean up. - * - * Mark Gross - */ - -/*#define DEBUG*/ - -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include - -#include - -/* - * locking rule: all changes to requests or notifiers lists - * or pm_qos_object list and pm_qos_objects need to happen with pm_qos_lock - * held, taken with _irqsave. One lock to rule them all - */ -enum pm_qos_type { - PM_QOS_MAX, /* return the largest value */ - PM_QOS_MIN /* return the smallest value */ -}; - -/* - * Note: The lockless read path depends on the CPU accessing - * target_value atomically. Atomic access is only guaranteed on all CPU - * types linux supports for 32 bit quantites - */ -struct pm_qos_object { - struct plist_head requests; - struct blocking_notifier_head *notifiers; - struct miscdevice pm_qos_power_miscdev; - char *name; - s32 target_value; /* Do not change to 64 bit */ - s32 default_value; - enum pm_qos_type type; -}; - -static DEFINE_SPINLOCK(pm_qos_lock); - -static struct pm_qos_object null_pm_qos; -static BLOCKING_NOTIFIER_HEAD(cpu_dma_lat_notifier); -static struct pm_qos_object cpu_dma_pm_qos = { - .requests = PLIST_HEAD_INIT(cpu_dma_pm_qos.requests), - .notifiers = &cpu_dma_lat_notifier, - .name = "cpu_dma_latency", - .target_value = PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE, - .default_value = PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE, - .type = PM_QOS_MIN, -}; - -static BLOCKING_NOTIFIER_HEAD(network_lat_notifier); -static struct pm_qos_object network_lat_pm_qos = { - .requests = PLIST_HEAD_INIT(network_lat_pm_qos.requests), - .notifiers = &network_lat_notifier, - .name = "network_latency", - .target_value = PM_QOS_NETWORK_LAT_DEFAULT_VALUE, - .default_value = PM_QOS_NETWORK_LAT_DEFAULT_VALUE, - .type = PM_QOS_MIN -}; - - -static BLOCKING_NOTIFIER_HEAD(network_throughput_notifier); -static struct pm_qos_object network_throughput_pm_qos = { - .requests = PLIST_HEAD_INIT(network_throughput_pm_qos.requests), - .notifiers = &network_throughput_notifier, - .name = "network_throughput", - .target_value = PM_QOS_NETWORK_THROUGHPUT_DEFAULT_VALUE, - .default_value = PM_QOS_NETWORK_THROUGHPUT_DEFAULT_VALUE, - .type = PM_QOS_MAX, -}; - - -static struct pm_qos_object *pm_qos_array[] = { - &null_pm_qos, - &cpu_dma_pm_qos, - &network_lat_pm_qos, - &network_throughput_pm_qos -}; - -static ssize_t pm_qos_power_write(struct file *filp, const char __user *buf, - size_t count, loff_t *f_pos); -static ssize_t pm_qos_power_read(struct file *filp, char __user *buf, - size_t count, loff_t *f_pos); -static int pm_qos_power_open(struct inode *inode, struct file *filp); -static int pm_qos_power_release(struct inode *inode, struct file *filp); - -static const struct file_operations pm_qos_power_fops = { - .write = pm_qos_power_write, - .read = pm_qos_power_read, - .open = pm_qos_power_open, - .release = pm_qos_power_release, - .llseek = noop_llseek, -}; - -/* unlocked internal variant */ -static inline int pm_qos_get_value(struct pm_qos_object *o) -{ - if (plist_head_empty(&o->requests)) - return o->default_value; - - switch (o->type) { - case PM_QOS_MIN: - return plist_first(&o->requests)->prio; - - case PM_QOS_MAX: - return plist_last(&o->requests)->prio; - - default: - /* runtime check for not using enum */ - BUG(); - } -} - -static inline s32 pm_qos_read_value(struct pm_qos_object *o) -{ - return o->target_value; -} - -static inline void pm_qos_set_value(struct pm_qos_object *o, s32 value) -{ - o->target_value = value; -} - -static void update_target(struct pm_qos_object *o, struct plist_node *node, - int del, int value) -{ - unsigned long flags; - int prev_value, curr_value; - - spin_lock_irqsave(&pm_qos_lock, flags); - prev_value = pm_qos_get_value(o); - /* PM_QOS_DEFAULT_VALUE is a signal that the value is unchanged */ - if (value != PM_QOS_DEFAULT_VALUE) { - /* - * to change the list, we atomically remove, reinit - * with new value and add, then see if the extremal - * changed - */ - plist_del(node, &o->requests); - plist_node_init(node, value); - plist_add(node, &o->requests); - } else if (del) { - plist_del(node, &o->requests); - } else { - plist_add(node, &o->requests); - } - curr_value = pm_qos_get_value(o); - pm_qos_set_value(o, curr_value); - spin_unlock_irqrestore(&pm_qos_lock, flags); - - if (prev_value != curr_value) - blocking_notifier_call_chain(o->notifiers, - (unsigned long)curr_value, - NULL); -} - -static int register_pm_qos_misc(struct pm_qos_object *qos) -{ - qos->pm_qos_power_miscdev.minor = MISC_DYNAMIC_MINOR; - qos->pm_qos_power_miscdev.name = qos->name; - qos->pm_qos_power_miscdev.fops = &pm_qos_power_fops; - - return misc_register(&qos->pm_qos_power_miscdev); -} - -static int find_pm_qos_object_by_minor(int minor) -{ - int pm_qos_class; - - for (pm_qos_class = 0; - pm_qos_class < PM_QOS_NUM_CLASSES; pm_qos_class++) { - if (minor == - pm_qos_array[pm_qos_class]->pm_qos_power_miscdev.minor) - return pm_qos_class; - } - return -1; -} - -/** - * pm_qos_request - returns current system wide qos expectation - * @pm_qos_class: identification of which qos value is requested - * - * This function returns the current target value. - */ -int pm_qos_request(int pm_qos_class) -{ - return pm_qos_read_value(pm_qos_array[pm_qos_class]); -} -EXPORT_SYMBOL_GPL(pm_qos_request); - -int pm_qos_request_active(struct pm_qos_request_list *req) -{ - return req->pm_qos_class != 0; -} -EXPORT_SYMBOL_GPL(pm_qos_request_active); - -/** - * pm_qos_add_request - inserts new qos request into the list - * @dep: pointer to a preallocated handle - * @pm_qos_class: identifies which list of qos request to use - * @value: defines the qos request - * - * This function inserts a new entry in the pm_qos_class list of requested qos - * performance characteristics. It recomputes the aggregate QoS expectations - * for the pm_qos_class of parameters and initializes the pm_qos_request_list - * handle. Caller needs to save this handle for later use in updates and - * removal. - */ - -void pm_qos_add_request(struct pm_qos_request_list *dep, - int pm_qos_class, s32 value) -{ - struct pm_qos_object *o = pm_qos_array[pm_qos_class]; - int new_value; - - if (pm_qos_request_active(dep)) { - WARN(1, KERN_ERR "pm_qos_add_request() called for already added request\n"); - return; - } - if (value == PM_QOS_DEFAULT_VALUE) - new_value = o->default_value; - else - new_value = value; - plist_node_init(&dep->list, new_value); - dep->pm_qos_class = pm_qos_class; - update_target(o, &dep->list, 0, PM_QOS_DEFAULT_VALUE); -} -EXPORT_SYMBOL_GPL(pm_qos_add_request); - -/** - * pm_qos_update_request - modifies an existing qos request - * @pm_qos_req : handle to list element holding a pm_qos request to use - * @value: defines the qos request - * - * Updates an existing qos request for the pm_qos_class of parameters along - * with updating the target pm_qos_class value. - * - * Attempts are made to make this code callable on hot code paths. - */ -void pm_qos_update_request(struct pm_qos_request_list *pm_qos_req, - s32 new_value) -{ - s32 temp; - struct pm_qos_object *o; - - if (!pm_qos_req) /*guard against callers passing in null */ - return; - - if (!pm_qos_request_active(pm_qos_req)) { - WARN(1, KERN_ERR "pm_qos_update_request() called for unknown object\n"); - return; - } - - o = pm_qos_array[pm_qos_req->pm_qos_class]; - - if (new_value == PM_QOS_DEFAULT_VALUE) - temp = o->default_value; - else - temp = new_value; - - if (temp != pm_qos_req->list.prio) - update_target(o, &pm_qos_req->list, 0, temp); -} -EXPORT_SYMBOL_GPL(pm_qos_update_request); - -/** - * pm_qos_remove_request - modifies an existing qos request - * @pm_qos_req: handle to request list element - * - * Will remove pm qos request from the list of requests and - * recompute the current target value for the pm_qos_class. Call this - * on slow code paths. - */ -void pm_qos_remove_request(struct pm_qos_request_list *pm_qos_req) -{ - struct pm_qos_object *o; - - if (pm_qos_req == NULL) - return; - /* silent return to keep pcm code cleaner */ - - if (!pm_qos_request_active(pm_qos_req)) { - WARN(1, KERN_ERR "pm_qos_remove_request() called for unknown object\n"); - return; - } - - o = pm_qos_array[pm_qos_req->pm_qos_class]; - update_target(o, &pm_qos_req->list, 1, PM_QOS_DEFAULT_VALUE); - memset(pm_qos_req, 0, sizeof(*pm_qos_req)); -} -EXPORT_SYMBOL_GPL(pm_qos_remove_request); - -/** - * pm_qos_add_notifier - sets notification entry for changes to target value - * @pm_qos_class: identifies which qos target changes should be notified. - * @notifier: notifier block managed by caller. - * - * will register the notifier into a notification chain that gets called - * upon changes to the pm_qos_class target value. - */ -int pm_qos_add_notifier(int pm_qos_class, struct notifier_block *notifier) -{ - int retval; - - retval = blocking_notifier_chain_register( - pm_qos_array[pm_qos_class]->notifiers, notifier); - - return retval; -} -EXPORT_SYMBOL_GPL(pm_qos_add_notifier); - -/** - * pm_qos_remove_notifier - deletes notification entry from chain. - * @pm_qos_class: identifies which qos target changes are notified. - * @notifier: notifier block to be removed. - * - * will remove the notifier from the notification chain that gets called - * upon changes to the pm_qos_class target value. - */ -int pm_qos_remove_notifier(int pm_qos_class, struct notifier_block *notifier) -{ - int retval; - - retval = blocking_notifier_chain_unregister( - pm_qos_array[pm_qos_class]->notifiers, notifier); - - return retval; -} -EXPORT_SYMBOL_GPL(pm_qos_remove_notifier); - -static int pm_qos_power_open(struct inode *inode, struct file *filp) -{ - long pm_qos_class; - - pm_qos_class = find_pm_qos_object_by_minor(iminor(inode)); - if (pm_qos_class >= 0) { - struct pm_qos_request_list *req = kzalloc(sizeof(*req), GFP_KERNEL); - if (!req) - return -ENOMEM; - - pm_qos_add_request(req, pm_qos_class, PM_QOS_DEFAULT_VALUE); - filp->private_data = req; - - if (filp->private_data) - return 0; - } - return -EPERM; -} - -static int pm_qos_power_release(struct inode *inode, struct file *filp) -{ - struct pm_qos_request_list *req; - - req = filp->private_data; - pm_qos_remove_request(req); - kfree(req); - - return 0; -} - - -static ssize_t pm_qos_power_read(struct file *filp, char __user *buf, - size_t count, loff_t *f_pos) -{ - s32 value; - unsigned long flags; - struct pm_qos_object *o; - struct pm_qos_request_list *pm_qos_req = filp->private_data; - - if (!pm_qos_req) - return -EINVAL; - if (!pm_qos_request_active(pm_qos_req)) - return -EINVAL; - - o = pm_qos_array[pm_qos_req->pm_qos_class]; - spin_lock_irqsave(&pm_qos_lock, flags); - value = pm_qos_get_value(o); - spin_unlock_irqrestore(&pm_qos_lock, flags); - - return simple_read_from_buffer(buf, count, f_pos, &value, sizeof(s32)); -} - -static ssize_t pm_qos_power_write(struct file *filp, const char __user *buf, - size_t count, loff_t *f_pos) -{ - s32 value; - struct pm_qos_request_list *pm_qos_req; - - if (count == sizeof(s32)) { - if (copy_from_user(&value, buf, sizeof(s32))) - return -EFAULT; - } else if (count <= 11) { /* ASCII perhaps? */ - char ascii_value[11]; - unsigned long int ulval; - int ret; - - if (copy_from_user(ascii_value, buf, count)) - return -EFAULT; - - if (count > 10) { - if (ascii_value[10] == '\n') - ascii_value[10] = '\0'; - else - return -EINVAL; - } else { - ascii_value[count] = '\0'; - } - ret = strict_strtoul(ascii_value, 16, &ulval); - if (ret) { - pr_debug("%s, 0x%lx, 0x%x\n", ascii_value, ulval, ret); - return -EINVAL; - } - value = (s32)lower_32_bits(ulval); - } else { - return -EINVAL; - } - - pm_qos_req = filp->private_data; - pm_qos_update_request(pm_qos_req, value); - - return count; -} - - -static int __init pm_qos_power_init(void) -{ - int ret = 0; - - ret = register_pm_qos_misc(&cpu_dma_pm_qos); - if (ret < 0) { - printk(KERN_ERR "pm_qos_param: cpu_dma_latency setup failed\n"); - return ret; - } - ret = register_pm_qos_misc(&network_lat_pm_qos); - if (ret < 0) { - printk(KERN_ERR "pm_qos_param: network_latency setup failed\n"); - return ret; - } - ret = register_pm_qos_misc(&network_throughput_pm_qos); - if (ret < 0) - printk(KERN_ERR - "pm_qos_param: network_throughput setup failed\n"); - - return ret; -} - -late_initcall(pm_qos_power_init); diff --git a/kernel/power/Makefile b/kernel/power/Makefile index c5ebc6a9064..ad6bdd8b401 100644 --- a/kernel/power/Makefile +++ b/kernel/power/Makefile @@ -1,7 +1,7 @@ ccflags-$(CONFIG_PM_DEBUG) := -DDEBUG -obj-$(CONFIG_PM) += main.o +obj-$(CONFIG_PM) += main.o qos.o obj-$(CONFIG_PM_SLEEP) += console.o obj-$(CONFIG_FREEZER) += process.o obj-$(CONFIG_SUSPEND) += suspend.o diff --git a/kernel/power/qos.c b/kernel/power/qos.c new file mode 100644 index 00000000000..61b47384329 --- /dev/null +++ b/kernel/power/qos.c @@ -0,0 +1,481 @@ +/* + * This module exposes the interface to kernel space for specifying + * QoS dependencies. It provides infrastructure for registration of: + * + * Dependents on a QoS value : register requests + * Watchers of QoS value : get notified when target QoS value changes + * + * This QoS design is best effort based. Dependents register their QoS needs. + * Watchers register to keep track of the current QoS needs of the system. + * + * There are 3 basic classes of QoS parameter: latency, timeout, throughput + * each have defined units: + * latency: usec + * timeout: usec <-- currently not used. + * throughput: kbs (kilo byte / sec) + * + * There are lists of pm_qos_objects each one wrapping requests, notifiers + * + * User mode requests on a QOS parameter register themselves to the + * subsystem by opening the device node /dev/... and writing there request to + * the node. As long as the process holds a file handle open to the node the + * client continues to be accounted for. Upon file release the usermode + * request is removed and a new qos target is computed. This way when the + * request that the application has is cleaned up when closes the file + * pointer or exits the pm_qos_object will get an opportunity to clean up. + * + * Mark Gross + */ + +/*#define DEBUG*/ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include + +/* + * locking rule: all changes to requests or notifiers lists + * or pm_qos_object list and pm_qos_objects need to happen with pm_qos_lock + * held, taken with _irqsave. One lock to rule them all + */ +enum pm_qos_type { + PM_QOS_MAX, /* return the largest value */ + PM_QOS_MIN /* return the smallest value */ +}; + +/* + * Note: The lockless read path depends on the CPU accessing + * target_value atomically. Atomic access is only guaranteed on all CPU + * types linux supports for 32 bit quantites + */ +struct pm_qos_object { + struct plist_head requests; + struct blocking_notifier_head *notifiers; + struct miscdevice pm_qos_power_miscdev; + char *name; + s32 target_value; /* Do not change to 64 bit */ + s32 default_value; + enum pm_qos_type type; +}; + +static DEFINE_SPINLOCK(pm_qos_lock); + +static struct pm_qos_object null_pm_qos; +static BLOCKING_NOTIFIER_HEAD(cpu_dma_lat_notifier); +static struct pm_qos_object cpu_dma_pm_qos = { + .requests = PLIST_HEAD_INIT(cpu_dma_pm_qos.requests), + .notifiers = &cpu_dma_lat_notifier, + .name = "cpu_dma_latency", + .target_value = PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE, + .default_value = PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE, + .type = PM_QOS_MIN, +}; + +static BLOCKING_NOTIFIER_HEAD(network_lat_notifier); +static struct pm_qos_object network_lat_pm_qos = { + .requests = PLIST_HEAD_INIT(network_lat_pm_qos.requests), + .notifiers = &network_lat_notifier, + .name = "network_latency", + .target_value = PM_QOS_NETWORK_LAT_DEFAULT_VALUE, + .default_value = PM_QOS_NETWORK_LAT_DEFAULT_VALUE, + .type = PM_QOS_MIN +}; + + +static BLOCKING_NOTIFIER_HEAD(network_throughput_notifier); +static struct pm_qos_object network_throughput_pm_qos = { + .requests = PLIST_HEAD_INIT(network_throughput_pm_qos.requests), + .notifiers = &network_throughput_notifier, + .name = "network_throughput", + .target_value = PM_QOS_NETWORK_THROUGHPUT_DEFAULT_VALUE, + .default_value = PM_QOS_NETWORK_THROUGHPUT_DEFAULT_VALUE, + .type = PM_QOS_MAX, +}; + + +static struct pm_qos_object *pm_qos_array[] = { + &null_pm_qos, + &cpu_dma_pm_qos, + &network_lat_pm_qos, + &network_throughput_pm_qos +}; + +static ssize_t pm_qos_power_write(struct file *filp, const char __user *buf, + size_t count, loff_t *f_pos); +static ssize_t pm_qos_power_read(struct file *filp, char __user *buf, + size_t count, loff_t *f_pos); +static int pm_qos_power_open(struct inode *inode, struct file *filp); +static int pm_qos_power_release(struct inode *inode, struct file *filp); + +static const struct file_operations pm_qos_power_fops = { + .write = pm_qos_power_write, + .read = pm_qos_power_read, + .open = pm_qos_power_open, + .release = pm_qos_power_release, + .llseek = noop_llseek, +}; + +/* unlocked internal variant */ +static inline int pm_qos_get_value(struct pm_qos_object *o) +{ + if (plist_head_empty(&o->requests)) + return o->default_value; + + switch (o->type) { + case PM_QOS_MIN: + return plist_first(&o->requests)->prio; + + case PM_QOS_MAX: + return plist_last(&o->requests)->prio; + + default: + /* runtime check for not using enum */ + BUG(); + } +} + +static inline s32 pm_qos_read_value(struct pm_qos_object *o) +{ + return o->target_value; +} + +static inline void pm_qos_set_value(struct pm_qos_object *o, s32 value) +{ + o->target_value = value; +} + +static void update_target(struct pm_qos_object *o, struct plist_node *node, + int del, int value) +{ + unsigned long flags; + int prev_value, curr_value; + + spin_lock_irqsave(&pm_qos_lock, flags); + prev_value = pm_qos_get_value(o); + /* PM_QOS_DEFAULT_VALUE is a signal that the value is unchanged */ + if (value != PM_QOS_DEFAULT_VALUE) { + /* + * to change the list, we atomically remove, reinit + * with new value and add, then see if the extremal + * changed + */ + plist_del(node, &o->requests); + plist_node_init(node, value); + plist_add(node, &o->requests); + } else if (del) { + plist_del(node, &o->requests); + } else { + plist_add(node, &o->requests); + } + curr_value = pm_qos_get_value(o); + pm_qos_set_value(o, curr_value); + spin_unlock_irqrestore(&pm_qos_lock, flags); + + if (prev_value != curr_value) + blocking_notifier_call_chain(o->notifiers, + (unsigned long)curr_value, + NULL); +} + +static int register_pm_qos_misc(struct pm_qos_object *qos) +{ + qos->pm_qos_power_miscdev.minor = MISC_DYNAMIC_MINOR; + qos->pm_qos_power_miscdev.name = qos->name; + qos->pm_qos_power_miscdev.fops = &pm_qos_power_fops; + + return misc_register(&qos->pm_qos_power_miscdev); +} + +static int find_pm_qos_object_by_minor(int minor) +{ + int pm_qos_class; + + for (pm_qos_class = 0; + pm_qos_class < PM_QOS_NUM_CLASSES; pm_qos_class++) { + if (minor == + pm_qos_array[pm_qos_class]->pm_qos_power_miscdev.minor) + return pm_qos_class; + } + return -1; +} + +/** + * pm_qos_request - returns current system wide qos expectation + * @pm_qos_class: identification of which qos value is requested + * + * This function returns the current target value. + */ +int pm_qos_request(int pm_qos_class) +{ + return pm_qos_read_value(pm_qos_array[pm_qos_class]); +} +EXPORT_SYMBOL_GPL(pm_qos_request); + +int pm_qos_request_active(struct pm_qos_request_list *req) +{ + return req->pm_qos_class != 0; +} +EXPORT_SYMBOL_GPL(pm_qos_request_active); + +/** + * pm_qos_add_request - inserts new qos request into the list + * @dep: pointer to a preallocated handle + * @pm_qos_class: identifies which list of qos request to use + * @value: defines the qos request + * + * This function inserts a new entry in the pm_qos_class list of requested qos + * performance characteristics. It recomputes the aggregate QoS expectations + * for the pm_qos_class of parameters and initializes the pm_qos_request_list + * handle. Caller needs to save this handle for later use in updates and + * removal. + */ + +void pm_qos_add_request(struct pm_qos_request_list *dep, + int pm_qos_class, s32 value) +{ + struct pm_qos_object *o = pm_qos_array[pm_qos_class]; + int new_value; + + if (pm_qos_request_active(dep)) { + WARN(1, KERN_ERR "pm_qos_add_request() called for already added request\n"); + return; + } + if (value == PM_QOS_DEFAULT_VALUE) + new_value = o->default_value; + else + new_value = value; + plist_node_init(&dep->list, new_value); + dep->pm_qos_class = pm_qos_class; + update_target(o, &dep->list, 0, PM_QOS_DEFAULT_VALUE); +} +EXPORT_SYMBOL_GPL(pm_qos_add_request); + +/** + * pm_qos_update_request - modifies an existing qos request + * @pm_qos_req : handle to list element holding a pm_qos request to use + * @value: defines the qos request + * + * Updates an existing qos request for the pm_qos_class of parameters along + * with updating the target pm_qos_class value. + * + * Attempts are made to make this code callable on hot code paths. + */ +void pm_qos_update_request(struct pm_qos_request_list *pm_qos_req, + s32 new_value) +{ + s32 temp; + struct pm_qos_object *o; + + if (!pm_qos_req) /*guard against callers passing in null */ + return; + + if (!pm_qos_request_active(pm_qos_req)) { + WARN(1, KERN_ERR "pm_qos_update_request() called for unknown object\n"); + return; + } + + o = pm_qos_array[pm_qos_req->pm_qos_class]; + + if (new_value == PM_QOS_DEFAULT_VALUE) + temp = o->default_value; + else + temp = new_value; + + if (temp != pm_qos_req->list.prio) + update_target(o, &pm_qos_req->list, 0, temp); +} +EXPORT_SYMBOL_GPL(pm_qos_update_request); + +/** + * pm_qos_remove_request - modifies an existing qos request + * @pm_qos_req: handle to request list element + * + * Will remove pm qos request from the list of requests and + * recompute the current target value for the pm_qos_class. Call this + * on slow code paths. + */ +void pm_qos_remove_request(struct pm_qos_request_list *pm_qos_req) +{ + struct pm_qos_object *o; + + if (pm_qos_req == NULL) + return; + /* silent return to keep pcm code cleaner */ + + if (!pm_qos_request_active(pm_qos_req)) { + WARN(1, KERN_ERR "pm_qos_remove_request() called for unknown object\n"); + return; + } + + o = pm_qos_array[pm_qos_req->pm_qos_class]; + update_target(o, &pm_qos_req->list, 1, PM_QOS_DEFAULT_VALUE); + memset(pm_qos_req, 0, sizeof(*pm_qos_req)); +} +EXPORT_SYMBOL_GPL(pm_qos_remove_request); + +/** + * pm_qos_add_notifier - sets notification entry for changes to target value + * @pm_qos_class: identifies which qos target changes should be notified. + * @notifier: notifier block managed by caller. + * + * will register the notifier into a notification chain that gets called + * upon changes to the pm_qos_class target value. + */ +int pm_qos_add_notifier(int pm_qos_class, struct notifier_block *notifier) +{ + int retval; + + retval = blocking_notifier_chain_register( + pm_qos_array[pm_qos_class]->notifiers, notifier); + + return retval; +} +EXPORT_SYMBOL_GPL(pm_qos_add_notifier); + +/** + * pm_qos_remove_notifier - deletes notification entry from chain. + * @pm_qos_class: identifies which qos target changes are notified. + * @notifier: notifier block to be removed. + * + * will remove the notifier from the notification chain that gets called + * upon changes to the pm_qos_class target value. + */ +int pm_qos_remove_notifier(int pm_qos_class, struct notifier_block *notifier) +{ + int retval; + + retval = blocking_notifier_chain_unregister( + pm_qos_array[pm_qos_class]->notifiers, notifier); + + return retval; +} +EXPORT_SYMBOL_GPL(pm_qos_remove_notifier); + +static int pm_qos_power_open(struct inode *inode, struct file *filp) +{ + long pm_qos_class; + + pm_qos_class = find_pm_qos_object_by_minor(iminor(inode)); + if (pm_qos_class >= 0) { + struct pm_qos_request_list *req = kzalloc(sizeof(*req), GFP_KERNEL); + if (!req) + return -ENOMEM; + + pm_qos_add_request(req, pm_qos_class, PM_QOS_DEFAULT_VALUE); + filp->private_data = req; + + if (filp->private_data) + return 0; + } + return -EPERM; +} + +static int pm_qos_power_release(struct inode *inode, struct file *filp) +{ + struct pm_qos_request_list *req; + + req = filp->private_data; + pm_qos_remove_request(req); + kfree(req); + + return 0; +} + + +static ssize_t pm_qos_power_read(struct file *filp, char __user *buf, + size_t count, loff_t *f_pos) +{ + s32 value; + unsigned long flags; + struct pm_qos_object *o; + struct pm_qos_request_list *pm_qos_req = filp->private_data; + + if (!pm_qos_req) + return -EINVAL; + if (!pm_qos_request_active(pm_qos_req)) + return -EINVAL; + + o = pm_qos_array[pm_qos_req->pm_qos_class]; + spin_lock_irqsave(&pm_qos_lock, flags); + value = pm_qos_get_value(o); + spin_unlock_irqrestore(&pm_qos_lock, flags); + + return simple_read_from_buffer(buf, count, f_pos, &value, sizeof(s32)); +} + +static ssize_t pm_qos_power_write(struct file *filp, const char __user *buf, + size_t count, loff_t *f_pos) +{ + s32 value; + struct pm_qos_request_list *pm_qos_req; + + if (count == sizeof(s32)) { + if (copy_from_user(&value, buf, sizeof(s32))) + return -EFAULT; + } else if (count <= 11) { /* ASCII perhaps? */ + char ascii_value[11]; + unsigned long int ulval; + int ret; + + if (copy_from_user(ascii_value, buf, count)) + return -EFAULT; + + if (count > 10) { + if (ascii_value[10] == '\n') + ascii_value[10] = '\0'; + else + return -EINVAL; + } else { + ascii_value[count] = '\0'; + } + ret = strict_strtoul(ascii_value, 16, &ulval); + if (ret) { + pr_debug("%s, 0x%lx, 0x%x\n", ascii_value, ulval, ret); + return -EINVAL; + } + value = (s32)lower_32_bits(ulval); + } else { + return -EINVAL; + } + + pm_qos_req = filp->private_data; + pm_qos_update_request(pm_qos_req, value); + + return count; +} + + +static int __init pm_qos_power_init(void) +{ + int ret = 0; + + ret = register_pm_qos_misc(&cpu_dma_pm_qos); + if (ret < 0) { + printk(KERN_ERR "pm_qos_param: cpu_dma_latency setup failed\n"); + return ret; + } + ret = register_pm_qos_misc(&network_lat_pm_qos); + if (ret < 0) { + printk(KERN_ERR "pm_qos_param: network_latency setup failed\n"); + return ret; + } + ret = register_pm_qos_misc(&network_throughput_pm_qos); + if (ret < 0) + printk(KERN_ERR + "pm_qos_param: network_throughput setup failed\n"); + + return ret; +} + +late_initcall(pm_qos_power_init); -- cgit v1.2.3-70-g09d2 From cc74998618a66d34651c784dd02412614c3e81cc Mon Sep 17 00:00:00 2001 From: Jean Pihet Date: Thu, 25 Aug 2011 15:35:12 +0200 Subject: PM QoS: Minor clean-ups - Misc fixes to improve code readability: * rename struct pm_qos_request_list to struct pm_qos_request, * rename pm_qos_req parameter to req in internal code, consistenly use req in the API parameters, * update the in-kernel API callers to the new parameters names, * rename of fields names (requests, list, node, constraints) Signed-off-by: Jean Pihet Acked-by: markgross Reviewed-by: Kevin Hilman Signed-off-by: Rafael J. Wysocki --- drivers/media/video/via-camera.c | 2 +- drivers/net/wireless/ipw2x00/ipw2100.c | 2 +- include/linux/netdevice.h | 2 +- include/linux/pm_qos.h | 22 ++++----- include/sound/pcm.h | 2 +- kernel/power/qos.c | 88 +++++++++++++++++----------------- 6 files changed, 59 insertions(+), 59 deletions(-) (limited to 'kernel') diff --git a/drivers/media/video/via-camera.c b/drivers/media/video/via-camera.c index b3ca3893f3d..fba6c6458cf 100644 --- a/drivers/media/video/via-camera.c +++ b/drivers/media/video/via-camera.c @@ -69,7 +69,7 @@ struct via_camera { struct mutex lock; enum viacam_opstate opstate; unsigned long flags; - struct pm_qos_request_list qos_request; + struct pm_qos_request qos_request; /* * GPIO info for power/reset management */ diff --git a/drivers/net/wireless/ipw2x00/ipw2100.c b/drivers/net/wireless/ipw2x00/ipw2100.c index aaab76ce602..db35f99cac1 100644 --- a/drivers/net/wireless/ipw2x00/ipw2100.c +++ b/drivers/net/wireless/ipw2x00/ipw2100.c @@ -174,7 +174,7 @@ that only one external action is invoked at a time. #define DRV_DESCRIPTION "Intel(R) PRO/Wireless 2100 Network Driver" #define DRV_COPYRIGHT "Copyright(c) 2003-2006 Intel Corporation" -static struct pm_qos_request_list ipw2100_pm_qos_req; +static struct pm_qos_request ipw2100_pm_qos_req; /* Debugging stuff */ #ifdef CONFIG_IPW2100_DEBUG diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index f72ac6b972b..f38ab5b7e76 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -964,7 +964,7 @@ struct net_device { */ char name[IFNAMSIZ]; - struct pm_qos_request_list pm_qos_req; + struct pm_qos_request pm_qos_req; /* device name hash chain */ struct hlist_node name_hlist; diff --git a/include/linux/pm_qos.h b/include/linux/pm_qos.h index 7ba675413b0..6b0968f8bc6 100644 --- a/include/linux/pm_qos.h +++ b/include/linux/pm_qos.h @@ -20,30 +20,30 @@ #define PM_QOS_NETWORK_LAT_DEFAULT_VALUE (2000 * USEC_PER_SEC) #define PM_QOS_NETWORK_THROUGHPUT_DEFAULT_VALUE 0 -struct pm_qos_request_list { - struct plist_node list; +struct pm_qos_request { + struct plist_node node; int pm_qos_class; }; #ifdef CONFIG_PM -void pm_qos_add_request(struct pm_qos_request_list *l, - int pm_qos_class, s32 value); -void pm_qos_update_request(struct pm_qos_request_list *pm_qos_req, +void pm_qos_add_request(struct pm_qos_request *req, int pm_qos_class, + s32 value); +void pm_qos_update_request(struct pm_qos_request *req, s32 new_value); -void pm_qos_remove_request(struct pm_qos_request_list *pm_qos_req); +void pm_qos_remove_request(struct pm_qos_request *req); int pm_qos_request(int pm_qos_class); int pm_qos_add_notifier(int pm_qos_class, struct notifier_block *notifier); int pm_qos_remove_notifier(int pm_qos_class, struct notifier_block *notifier); -int pm_qos_request_active(struct pm_qos_request_list *req); +int pm_qos_request_active(struct pm_qos_request *req); #else -static inline void pm_qos_add_request(struct pm_qos_request_list *l, +static inline void pm_qos_add_request(struct pm_qos_request *req, int pm_qos_class, s32 value) { return; } -static inline void pm_qos_update_request(struct pm_qos_request_list *pm_qos_req, +static inline void pm_qos_update_request(struct pm_qos_request *req, s32 new_value) { return; } -static inline void pm_qos_remove_request(struct pm_qos_request_list *pm_qos_req) +static inline void pm_qos_remove_request(struct pm_qos_request *req) { return; } static inline int pm_qos_request(int pm_qos_class) @@ -54,7 +54,7 @@ static inline int pm_qos_add_notifier(int pm_qos_class, static inline int pm_qos_remove_notifier(int pm_qos_class, struct notifier_block *notifier) { return 0; } -static inline int pm_qos_request_active(struct pm_qos_request_list *req) +static inline int pm_qos_request_active(struct pm_qos_request *req) { return 0; } #endif diff --git a/include/sound/pcm.h b/include/sound/pcm.h index 666ee91e8a2..54cb079b7bf 100644 --- a/include/sound/pcm.h +++ b/include/sound/pcm.h @@ -373,7 +373,7 @@ struct snd_pcm_substream { int number; char name[32]; /* substream name */ int stream; /* stream (direction) */ - struct pm_qos_request_list latency_pm_qos_req; /* pm_qos request */ + struct pm_qos_request latency_pm_qos_req; /* pm_qos request */ size_t buffer_bytes_max; /* limit ring buffer size */ struct snd_dma_buffer dma_buffer; unsigned int dma_buf_id; diff --git a/kernel/power/qos.c b/kernel/power/qos.c index 61b47384329..aa52c44e608 100644 --- a/kernel/power/qos.c +++ b/kernel/power/qos.c @@ -45,7 +45,7 @@ #include /* - * locking rule: all changes to requests or notifiers lists + * locking rule: all changes to constraints or notifiers lists * or pm_qos_object list and pm_qos_objects need to happen with pm_qos_lock * held, taken with _irqsave. One lock to rule them all */ @@ -60,7 +60,7 @@ enum pm_qos_type { * types linux supports for 32 bit quantites */ struct pm_qos_object { - struct plist_head requests; + struct plist_head constraints; struct blocking_notifier_head *notifiers; struct miscdevice pm_qos_power_miscdev; char *name; @@ -74,7 +74,7 @@ static DEFINE_SPINLOCK(pm_qos_lock); static struct pm_qos_object null_pm_qos; static BLOCKING_NOTIFIER_HEAD(cpu_dma_lat_notifier); static struct pm_qos_object cpu_dma_pm_qos = { - .requests = PLIST_HEAD_INIT(cpu_dma_pm_qos.requests), + .constraints = PLIST_HEAD_INIT(cpu_dma_pm_qos.constraints), .notifiers = &cpu_dma_lat_notifier, .name = "cpu_dma_latency", .target_value = PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE, @@ -84,7 +84,7 @@ static struct pm_qos_object cpu_dma_pm_qos = { static BLOCKING_NOTIFIER_HEAD(network_lat_notifier); static struct pm_qos_object network_lat_pm_qos = { - .requests = PLIST_HEAD_INIT(network_lat_pm_qos.requests), + .constraints = PLIST_HEAD_INIT(network_lat_pm_qos.constraints), .notifiers = &network_lat_notifier, .name = "network_latency", .target_value = PM_QOS_NETWORK_LAT_DEFAULT_VALUE, @@ -95,7 +95,7 @@ static struct pm_qos_object network_lat_pm_qos = { static BLOCKING_NOTIFIER_HEAD(network_throughput_notifier); static struct pm_qos_object network_throughput_pm_qos = { - .requests = PLIST_HEAD_INIT(network_throughput_pm_qos.requests), + .constraints = PLIST_HEAD_INIT(network_throughput_pm_qos.constraints), .notifiers = &network_throughput_notifier, .name = "network_throughput", .target_value = PM_QOS_NETWORK_THROUGHPUT_DEFAULT_VALUE, @@ -129,15 +129,15 @@ static const struct file_operations pm_qos_power_fops = { /* unlocked internal variant */ static inline int pm_qos_get_value(struct pm_qos_object *o) { - if (plist_head_empty(&o->requests)) + if (plist_head_empty(&o->constraints)) return o->default_value; switch (o->type) { case PM_QOS_MIN: - return plist_first(&o->requests)->prio; + return plist_first(&o->constraints)->prio; case PM_QOS_MAX: - return plist_last(&o->requests)->prio; + return plist_last(&o->constraints)->prio; default: /* runtime check for not using enum */ @@ -170,13 +170,13 @@ static void update_target(struct pm_qos_object *o, struct plist_node *node, * with new value and add, then see if the extremal * changed */ - plist_del(node, &o->requests); + plist_del(node, &o->constraints); plist_node_init(node, value); - plist_add(node, &o->requests); + plist_add(node, &o->constraints); } else if (del) { - plist_del(node, &o->requests); + plist_del(node, &o->constraints); } else { - plist_add(node, &o->requests); + plist_add(node, &o->constraints); } curr_value = pm_qos_get_value(o); pm_qos_set_value(o, curr_value); @@ -222,7 +222,7 @@ int pm_qos_request(int pm_qos_class) } EXPORT_SYMBOL_GPL(pm_qos_request); -int pm_qos_request_active(struct pm_qos_request_list *req) +int pm_qos_request_active(struct pm_qos_request *req) { return req->pm_qos_class != 0; } @@ -230,24 +230,24 @@ EXPORT_SYMBOL_GPL(pm_qos_request_active); /** * pm_qos_add_request - inserts new qos request into the list - * @dep: pointer to a preallocated handle + * @req: pointer to a preallocated handle * @pm_qos_class: identifies which list of qos request to use * @value: defines the qos request * * This function inserts a new entry in the pm_qos_class list of requested qos * performance characteristics. It recomputes the aggregate QoS expectations - * for the pm_qos_class of parameters and initializes the pm_qos_request_list + * for the pm_qos_class of parameters and initializes the pm_qos_request * handle. Caller needs to save this handle for later use in updates and * removal. */ -void pm_qos_add_request(struct pm_qos_request_list *dep, +void pm_qos_add_request(struct pm_qos_request *req, int pm_qos_class, s32 value) { struct pm_qos_object *o = pm_qos_array[pm_qos_class]; int new_value; - if (pm_qos_request_active(dep)) { + if (pm_qos_request_active(req)) { WARN(1, KERN_ERR "pm_qos_add_request() called for already added request\n"); return; } @@ -255,15 +255,15 @@ void pm_qos_add_request(struct pm_qos_request_list *dep, new_value = o->default_value; else new_value = value; - plist_node_init(&dep->list, new_value); - dep->pm_qos_class = pm_qos_class; - update_target(o, &dep->list, 0, PM_QOS_DEFAULT_VALUE); + plist_node_init(&req->node, new_value); + req->pm_qos_class = pm_qos_class; + update_target(o, &req->node, 0, PM_QOS_DEFAULT_VALUE); } EXPORT_SYMBOL_GPL(pm_qos_add_request); /** * pm_qos_update_request - modifies an existing qos request - * @pm_qos_req : handle to list element holding a pm_qos request to use + * @req : handle to list element holding a pm_qos request to use * @value: defines the qos request * * Updates an existing qos request for the pm_qos_class of parameters along @@ -271,56 +271,56 @@ EXPORT_SYMBOL_GPL(pm_qos_add_request); * * Attempts are made to make this code callable on hot code paths. */ -void pm_qos_update_request(struct pm_qos_request_list *pm_qos_req, +void pm_qos_update_request(struct pm_qos_request *req, s32 new_value) { s32 temp; struct pm_qos_object *o; - if (!pm_qos_req) /*guard against callers passing in null */ + if (!req) /*guard against callers passing in null */ return; - if (!pm_qos_request_active(pm_qos_req)) { + if (!pm_qos_request_active(req)) { WARN(1, KERN_ERR "pm_qos_update_request() called for unknown object\n"); return; } - o = pm_qos_array[pm_qos_req->pm_qos_class]; + o = pm_qos_array[req->pm_qos_class]; if (new_value == PM_QOS_DEFAULT_VALUE) temp = o->default_value; else temp = new_value; - if (temp != pm_qos_req->list.prio) - update_target(o, &pm_qos_req->list, 0, temp); + if (temp != req->node.prio) + update_target(o, &req->node, 0, temp); } EXPORT_SYMBOL_GPL(pm_qos_update_request); /** * pm_qos_remove_request - modifies an existing qos request - * @pm_qos_req: handle to request list element + * @req: handle to request list element * - * Will remove pm qos request from the list of requests and + * Will remove pm qos request from the list of constraints and * recompute the current target value for the pm_qos_class. Call this * on slow code paths. */ -void pm_qos_remove_request(struct pm_qos_request_list *pm_qos_req) +void pm_qos_remove_request(struct pm_qos_request *req) { struct pm_qos_object *o; - if (pm_qos_req == NULL) + if (req == NULL) return; /* silent return to keep pcm code cleaner */ - if (!pm_qos_request_active(pm_qos_req)) { + if (!pm_qos_request_active(req)) { WARN(1, KERN_ERR "pm_qos_remove_request() called for unknown object\n"); return; } - o = pm_qos_array[pm_qos_req->pm_qos_class]; - update_target(o, &pm_qos_req->list, 1, PM_QOS_DEFAULT_VALUE); - memset(pm_qos_req, 0, sizeof(*pm_qos_req)); + o = pm_qos_array[req->pm_qos_class]; + update_target(o, &req->node, 1, PM_QOS_DEFAULT_VALUE); + memset(req, 0, sizeof(*req)); } EXPORT_SYMBOL_GPL(pm_qos_remove_request); @@ -368,7 +368,7 @@ static int pm_qos_power_open(struct inode *inode, struct file *filp) pm_qos_class = find_pm_qos_object_by_minor(iminor(inode)); if (pm_qos_class >= 0) { - struct pm_qos_request_list *req = kzalloc(sizeof(*req), GFP_KERNEL); + struct pm_qos_request *req = kzalloc(sizeof(*req), GFP_KERNEL); if (!req) return -ENOMEM; @@ -383,7 +383,7 @@ static int pm_qos_power_open(struct inode *inode, struct file *filp) static int pm_qos_power_release(struct inode *inode, struct file *filp) { - struct pm_qos_request_list *req; + struct pm_qos_request *req; req = filp->private_data; pm_qos_remove_request(req); @@ -399,14 +399,14 @@ static ssize_t pm_qos_power_read(struct file *filp, char __user *buf, s32 value; unsigned long flags; struct pm_qos_object *o; - struct pm_qos_request_list *pm_qos_req = filp->private_data; + struct pm_qos_request *req = filp->private_data; - if (!pm_qos_req) + if (!req) return -EINVAL; - if (!pm_qos_request_active(pm_qos_req)) + if (!pm_qos_request_active(req)) return -EINVAL; - o = pm_qos_array[pm_qos_req->pm_qos_class]; + o = pm_qos_array[req->pm_qos_class]; spin_lock_irqsave(&pm_qos_lock, flags); value = pm_qos_get_value(o); spin_unlock_irqrestore(&pm_qos_lock, flags); @@ -418,7 +418,7 @@ static ssize_t pm_qos_power_write(struct file *filp, const char __user *buf, size_t count, loff_t *f_pos) { s32 value; - struct pm_qos_request_list *pm_qos_req; + struct pm_qos_request *req; if (count == sizeof(s32)) { if (copy_from_user(&value, buf, sizeof(s32))) @@ -449,8 +449,8 @@ static ssize_t pm_qos_power_write(struct file *filp, const char __user *buf, return -EINVAL; } - pm_qos_req = filp->private_data; - pm_qos_update_request(pm_qos_req, value); + req = filp->private_data; + pm_qos_update_request(req, value); return count; } -- cgit v1.2.3-70-g09d2 From 4a31a33425a1eb92f6a0b9846f081842268361c8 Mon Sep 17 00:00:00 2001 From: Jean Pihet Date: Thu, 25 Aug 2011 15:35:20 +0200 Subject: PM QoS: Code reorganization Move around the PM QoS misc devices management code for better readability. Signed-off-by: Jean Pihet Acked-by: markgross Reviewed-by: Kevin Hilman Signed-off-by: Rafael J. Wysocki --- kernel/power/qos.c | 45 +++++++++++++++++++++++---------------------- 1 file changed, 23 insertions(+), 22 deletions(-) (limited to 'kernel') diff --git a/kernel/power/qos.c b/kernel/power/qos.c index aa52c44e608..788c4cfe0cd 100644 --- a/kernel/power/qos.c +++ b/kernel/power/qos.c @@ -188,28 +188,6 @@ static void update_target(struct pm_qos_object *o, struct plist_node *node, NULL); } -static int register_pm_qos_misc(struct pm_qos_object *qos) -{ - qos->pm_qos_power_miscdev.minor = MISC_DYNAMIC_MINOR; - qos->pm_qos_power_miscdev.name = qos->name; - qos->pm_qos_power_miscdev.fops = &pm_qos_power_fops; - - return misc_register(&qos->pm_qos_power_miscdev); -} - -static int find_pm_qos_object_by_minor(int minor) -{ - int pm_qos_class; - - for (pm_qos_class = 0; - pm_qos_class < PM_QOS_NUM_CLASSES; pm_qos_class++) { - if (minor == - pm_qos_array[pm_qos_class]->pm_qos_power_miscdev.minor) - return pm_qos_class; - } - return -1; -} - /** * pm_qos_request - returns current system wide qos expectation * @pm_qos_class: identification of which qos value is requested @@ -362,6 +340,29 @@ int pm_qos_remove_notifier(int pm_qos_class, struct notifier_block *notifier) } EXPORT_SYMBOL_GPL(pm_qos_remove_notifier); +/* User space interface to PM QoS classes via misc devices */ +static int register_pm_qos_misc(struct pm_qos_object *qos) +{ + qos->pm_qos_power_miscdev.minor = MISC_DYNAMIC_MINOR; + qos->pm_qos_power_miscdev.name = qos->name; + qos->pm_qos_power_miscdev.fops = &pm_qos_power_fops; + + return misc_register(&qos->pm_qos_power_miscdev); +} + +static int find_pm_qos_object_by_minor(int minor) +{ + int pm_qos_class; + + for (pm_qos_class = 0; + pm_qos_class < PM_QOS_NUM_CLASSES; pm_qos_class++) { + if (minor == + pm_qos_array[pm_qos_class]->pm_qos_power_miscdev.minor) + return pm_qos_class; + } + return -1; +} + static int pm_qos_power_open(struct inode *inode, struct file *filp) { long pm_qos_class; -- cgit v1.2.3-70-g09d2 From 4e1779baaa542c83b459b0a56585e0c1a04c7782 Mon Sep 17 00:00:00 2001 From: Jean Pihet Date: Thu, 25 Aug 2011 15:35:27 +0200 Subject: PM QoS: Reorganize data structs In preparation for the per-device constratins support, re-organize the data strctures: - add a struct pm_qos_constraints which contains the constraints related data - update struct pm_qos_object contents to the PM QoS internal object data. Add a pointer to struct pm_qos_constraints - update the internal code to use the new data structs. Signed-off-by: Jean Pihet Reviewed-by: Kevin Hilman Signed-off-by: Rafael J. Wysocki --- include/linux/pm_qos.h | 19 +++++++++++ kernel/power/qos.c | 85 ++++++++++++++++++++++++-------------------------- 2 files changed, 60 insertions(+), 44 deletions(-) (limited to 'kernel') diff --git a/include/linux/pm_qos.h b/include/linux/pm_qos.h index 6b0968f8bc6..97723113ae9 100644 --- a/include/linux/pm_qos.h +++ b/include/linux/pm_qos.h @@ -25,6 +25,25 @@ struct pm_qos_request { int pm_qos_class; }; +enum pm_qos_type { + PM_QOS_UNITIALIZED, + PM_QOS_MAX, /* return the largest value */ + PM_QOS_MIN /* return the smallest value */ +}; + +/* + * Note: The lockless read path depends on the CPU accessing + * target_value atomically. Atomic access is only guaranteed on all CPU + * types linux supports for 32 bit quantites + */ +struct pm_qos_constraints { + struct plist_head list; + s32 target_value; /* Do not change to 64 bit */ + s32 default_value; + enum pm_qos_type type; + struct blocking_notifier_head *notifiers; +}; + #ifdef CONFIG_PM void pm_qos_add_request(struct pm_qos_request *req, int pm_qos_class, s32 value); diff --git a/kernel/power/qos.c b/kernel/power/qos.c index 788c4cfe0cd..4a35fe50b77 100644 --- a/kernel/power/qos.c +++ b/kernel/power/qos.c @@ -49,58 +49,53 @@ * or pm_qos_object list and pm_qos_objects need to happen with pm_qos_lock * held, taken with _irqsave. One lock to rule them all */ -enum pm_qos_type { - PM_QOS_MAX, /* return the largest value */ - PM_QOS_MIN /* return the smallest value */ -}; - -/* - * Note: The lockless read path depends on the CPU accessing - * target_value atomically. Atomic access is only guaranteed on all CPU - * types linux supports for 32 bit quantites - */ struct pm_qos_object { - struct plist_head constraints; - struct blocking_notifier_head *notifiers; + struct pm_qos_constraints *constraints; struct miscdevice pm_qos_power_miscdev; char *name; - s32 target_value; /* Do not change to 64 bit */ - s32 default_value; - enum pm_qos_type type; }; static DEFINE_SPINLOCK(pm_qos_lock); static struct pm_qos_object null_pm_qos; + static BLOCKING_NOTIFIER_HEAD(cpu_dma_lat_notifier); -static struct pm_qos_object cpu_dma_pm_qos = { - .constraints = PLIST_HEAD_INIT(cpu_dma_pm_qos.constraints), - .notifiers = &cpu_dma_lat_notifier, - .name = "cpu_dma_latency", +static struct pm_qos_constraints cpu_dma_constraints = { + .list = PLIST_HEAD_INIT(cpu_dma_constraints.list), .target_value = PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE, .default_value = PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE, .type = PM_QOS_MIN, + .notifiers = &cpu_dma_lat_notifier, +}; +static struct pm_qos_object cpu_dma_pm_qos = { + .constraints = &cpu_dma_constraints, }; static BLOCKING_NOTIFIER_HEAD(network_lat_notifier); -static struct pm_qos_object network_lat_pm_qos = { - .constraints = PLIST_HEAD_INIT(network_lat_pm_qos.constraints), - .notifiers = &network_lat_notifier, - .name = "network_latency", +static struct pm_qos_constraints network_lat_constraints = { + .list = PLIST_HEAD_INIT(network_lat_constraints.list), .target_value = PM_QOS_NETWORK_LAT_DEFAULT_VALUE, .default_value = PM_QOS_NETWORK_LAT_DEFAULT_VALUE, - .type = PM_QOS_MIN + .type = PM_QOS_MIN, + .notifiers = &network_lat_notifier, +}; +static struct pm_qos_object network_lat_pm_qos = { + .constraints = &network_lat_constraints, + .name = "network_latency", }; static BLOCKING_NOTIFIER_HEAD(network_throughput_notifier); -static struct pm_qos_object network_throughput_pm_qos = { - .constraints = PLIST_HEAD_INIT(network_throughput_pm_qos.constraints), - .notifiers = &network_throughput_notifier, - .name = "network_throughput", +static struct pm_qos_constraints network_tput_constraints = { + .list = PLIST_HEAD_INIT(network_tput_constraints.list), .target_value = PM_QOS_NETWORK_THROUGHPUT_DEFAULT_VALUE, .default_value = PM_QOS_NETWORK_THROUGHPUT_DEFAULT_VALUE, .type = PM_QOS_MAX, + .notifiers = &network_throughput_notifier, +}; +static struct pm_qos_object network_throughput_pm_qos = { + .constraints = &network_tput_constraints, + .name = "network_throughput", }; @@ -129,15 +124,15 @@ static const struct file_operations pm_qos_power_fops = { /* unlocked internal variant */ static inline int pm_qos_get_value(struct pm_qos_object *o) { - if (plist_head_empty(&o->constraints)) - return o->default_value; + if (plist_head_empty(&o->constraints->list)) + return o->constraints->default_value; - switch (o->type) { + switch (o->constraints->type) { case PM_QOS_MIN: - return plist_first(&o->constraints)->prio; + return plist_first(&o->constraints->list)->prio; case PM_QOS_MAX: - return plist_last(&o->constraints)->prio; + return plist_last(&o->constraints->list)->prio; default: /* runtime check for not using enum */ @@ -147,12 +142,12 @@ static inline int pm_qos_get_value(struct pm_qos_object *o) static inline s32 pm_qos_read_value(struct pm_qos_object *o) { - return o->target_value; + return o->constraints->target_value; } static inline void pm_qos_set_value(struct pm_qos_object *o, s32 value) { - o->target_value = value; + o->constraints->target_value = value; } static void update_target(struct pm_qos_object *o, struct plist_node *node, @@ -170,20 +165,20 @@ static void update_target(struct pm_qos_object *o, struct plist_node *node, * with new value and add, then see if the extremal * changed */ - plist_del(node, &o->constraints); + plist_del(node, &o->constraints->list); plist_node_init(node, value); - plist_add(node, &o->constraints); + plist_add(node, &o->constraints->list); } else if (del) { - plist_del(node, &o->constraints); + plist_del(node, &o->constraints->list); } else { - plist_add(node, &o->constraints); + plist_add(node, &o->constraints->list); } curr_value = pm_qos_get_value(o); pm_qos_set_value(o, curr_value); spin_unlock_irqrestore(&pm_qos_lock, flags); if (prev_value != curr_value) - blocking_notifier_call_chain(o->notifiers, + blocking_notifier_call_chain(o->constraints->notifiers, (unsigned long)curr_value, NULL); } @@ -230,7 +225,7 @@ void pm_qos_add_request(struct pm_qos_request *req, return; } if (value == PM_QOS_DEFAULT_VALUE) - new_value = o->default_value; + new_value = o->constraints->default_value; else new_value = value; plist_node_init(&req->node, new_value); @@ -266,7 +261,7 @@ void pm_qos_update_request(struct pm_qos_request *req, o = pm_qos_array[req->pm_qos_class]; if (new_value == PM_QOS_DEFAULT_VALUE) - temp = o->default_value; + temp = o->constraints->default_value; else temp = new_value; @@ -315,7 +310,8 @@ int pm_qos_add_notifier(int pm_qos_class, struct notifier_block *notifier) int retval; retval = blocking_notifier_chain_register( - pm_qos_array[pm_qos_class]->notifiers, notifier); + pm_qos_array[pm_qos_class]->constraints->notifiers, + notifier); return retval; } @@ -334,7 +330,8 @@ int pm_qos_remove_notifier(int pm_qos_class, struct notifier_block *notifier) int retval; retval = blocking_notifier_chain_unregister( - pm_qos_array[pm_qos_class]->notifiers, notifier); + pm_qos_array[pm_qos_class]->constraints->notifiers, + notifier); return retval; } -- cgit v1.2.3-70-g09d2 From abe98ec2d86279fe821c9051003a0abc43444f15 Mon Sep 17 00:00:00 2001 From: Jean Pihet Date: Thu, 25 Aug 2011 15:35:34 +0200 Subject: PM QoS: Generalize and export constraints management code In preparation for the per-device constratins support: - rename update_target to pm_qos_update_target - generalize and export pm_qos_update_target for usage by the upcoming per-device latency constraints framework: * operate on struct pm_qos_constraints for constraints management, * introduce an 'action' parameter for constraints add/update/remove, * the return value indicates if the aggregated constraint value has changed, - update the internal code to operate on struct pm_qos_constraints - add a NULL pointer check in the API functions Signed-off-by: Jean Pihet Reviewed-by: Kevin Hilman Signed-off-by: Rafael J. Wysocki --- include/linux/pm_qos.h | 14 ++++++ kernel/power/qos.c | 123 +++++++++++++++++++++++++++---------------------- 2 files changed, 81 insertions(+), 56 deletions(-) (limited to 'kernel') diff --git a/include/linux/pm_qos.h b/include/linux/pm_qos.h index 97723113ae9..84aa1508989 100644 --- a/include/linux/pm_qos.h +++ b/include/linux/pm_qos.h @@ -44,7 +44,16 @@ struct pm_qos_constraints { struct blocking_notifier_head *notifiers; }; +/* Action requested to pm_qos_update_target */ +enum pm_qos_req_action { + PM_QOS_ADD_REQ, /* Add a new request */ + PM_QOS_UPDATE_REQ, /* Update an existing request */ + PM_QOS_REMOVE_REQ /* Remove an existing request */ +}; + #ifdef CONFIG_PM +int pm_qos_update_target(struct pm_qos_constraints *c, struct plist_node *node, + enum pm_qos_req_action action, int value); void pm_qos_add_request(struct pm_qos_request *req, int pm_qos_class, s32 value); void pm_qos_update_request(struct pm_qos_request *req, @@ -56,6 +65,11 @@ int pm_qos_add_notifier(int pm_qos_class, struct notifier_block *notifier); int pm_qos_remove_notifier(int pm_qos_class, struct notifier_block *notifier); int pm_qos_request_active(struct pm_qos_request *req); #else +static inline int pm_qos_update_target(struct pm_qos_constraints *c, + struct plist_node *node, + enum pm_qos_req_action action, + int value) + { return 0; } static inline void pm_qos_add_request(struct pm_qos_request *req, int pm_qos_class, s32 value) { return; } diff --git a/kernel/power/qos.c b/kernel/power/qos.c index 4a35fe50b77..7c7cd181cab 100644 --- a/kernel/power/qos.c +++ b/kernel/power/qos.c @@ -122,17 +122,17 @@ static const struct file_operations pm_qos_power_fops = { }; /* unlocked internal variant */ -static inline int pm_qos_get_value(struct pm_qos_object *o) +static inline int pm_qos_get_value(struct pm_qos_constraints *c) { - if (plist_head_empty(&o->constraints->list)) - return o->constraints->default_value; + if (plist_head_empty(&c->list)) + return c->default_value; - switch (o->constraints->type) { + switch (c->type) { case PM_QOS_MIN: - return plist_first(&o->constraints->list)->prio; + return plist_first(&c->list)->prio; case PM_QOS_MAX: - return plist_last(&o->constraints->list)->prio; + return plist_last(&c->list)->prio; default: /* runtime check for not using enum */ @@ -140,47 +140,73 @@ static inline int pm_qos_get_value(struct pm_qos_object *o) } } -static inline s32 pm_qos_read_value(struct pm_qos_object *o) +static inline s32 pm_qos_read_value(struct pm_qos_constraints *c) { - return o->constraints->target_value; + return c->target_value; } -static inline void pm_qos_set_value(struct pm_qos_object *o, s32 value) +static inline void pm_qos_set_value(struct pm_qos_constraints *c, s32 value) { - o->constraints->target_value = value; + c->target_value = value; } -static void update_target(struct pm_qos_object *o, struct plist_node *node, - int del, int value) +/** + * pm_qos_update_target - manages the constraints list and calls the notifiers + * if needed + * @c: constraints data struct + * @node: request to add to the list, to update or to remove + * @action: action to take on the constraints list + * @value: value of the request to add or update + * + * This function returns 1 if the aggregated constraint value has changed, 0 + * otherwise. + */ +int pm_qos_update_target(struct pm_qos_constraints *c, struct plist_node *node, + enum pm_qos_req_action action, int value) { unsigned long flags; - int prev_value, curr_value; + int prev_value, curr_value, new_value; spin_lock_irqsave(&pm_qos_lock, flags); - prev_value = pm_qos_get_value(o); - /* PM_QOS_DEFAULT_VALUE is a signal that the value is unchanged */ - if (value != PM_QOS_DEFAULT_VALUE) { + prev_value = pm_qos_get_value(c); + if (value == PM_QOS_DEFAULT_VALUE) + new_value = c->default_value; + else + new_value = value; + + switch (action) { + case PM_QOS_REMOVE_REQ: + plist_del(node, &c->list); + break; + case PM_QOS_UPDATE_REQ: /* * to change the list, we atomically remove, reinit * with new value and add, then see if the extremal * changed */ - plist_del(node, &o->constraints->list); - plist_node_init(node, value); - plist_add(node, &o->constraints->list); - } else if (del) { - plist_del(node, &o->constraints->list); - } else { - plist_add(node, &o->constraints->list); + plist_del(node, &c->list); + case PM_QOS_ADD_REQ: + plist_node_init(node, new_value); + plist_add(node, &c->list); + break; + default: + /* no action */ + ; } - curr_value = pm_qos_get_value(o); - pm_qos_set_value(o, curr_value); + + curr_value = pm_qos_get_value(c); + pm_qos_set_value(c, curr_value); + spin_unlock_irqrestore(&pm_qos_lock, flags); - if (prev_value != curr_value) - blocking_notifier_call_chain(o->constraints->notifiers, + if (prev_value != curr_value) { + blocking_notifier_call_chain(c->notifiers, (unsigned long)curr_value, NULL); + return 1; + } else { + return 0; + } } /** @@ -191,7 +217,7 @@ static void update_target(struct pm_qos_object *o, struct plist_node *node, */ int pm_qos_request(int pm_qos_class) { - return pm_qos_read_value(pm_qos_array[pm_qos_class]); + return pm_qos_read_value(pm_qos_array[pm_qos_class]->constraints); } EXPORT_SYMBOL_GPL(pm_qos_request); @@ -217,20 +243,16 @@ EXPORT_SYMBOL_GPL(pm_qos_request_active); void pm_qos_add_request(struct pm_qos_request *req, int pm_qos_class, s32 value) { - struct pm_qos_object *o = pm_qos_array[pm_qos_class]; - int new_value; + if (!req) /*guard against callers passing in null */ + return; if (pm_qos_request_active(req)) { WARN(1, KERN_ERR "pm_qos_add_request() called for already added request\n"); return; } - if (value == PM_QOS_DEFAULT_VALUE) - new_value = o->constraints->default_value; - else - new_value = value; - plist_node_init(&req->node, new_value); req->pm_qos_class = pm_qos_class; - update_target(o, &req->node, 0, PM_QOS_DEFAULT_VALUE); + pm_qos_update_target(pm_qos_array[pm_qos_class]->constraints, + &req->node, PM_QOS_ADD_REQ, value); } EXPORT_SYMBOL_GPL(pm_qos_add_request); @@ -247,9 +269,6 @@ EXPORT_SYMBOL_GPL(pm_qos_add_request); void pm_qos_update_request(struct pm_qos_request *req, s32 new_value) { - s32 temp; - struct pm_qos_object *o; - if (!req) /*guard against callers passing in null */ return; @@ -258,15 +277,10 @@ void pm_qos_update_request(struct pm_qos_request *req, return; } - o = pm_qos_array[req->pm_qos_class]; - - if (new_value == PM_QOS_DEFAULT_VALUE) - temp = o->constraints->default_value; - else - temp = new_value; - - if (temp != req->node.prio) - update_target(o, &req->node, 0, temp); + if (new_value != req->node.prio) + pm_qos_update_target( + pm_qos_array[req->pm_qos_class]->constraints, + &req->node, PM_QOS_UPDATE_REQ, new_value); } EXPORT_SYMBOL_GPL(pm_qos_update_request); @@ -280,9 +294,7 @@ EXPORT_SYMBOL_GPL(pm_qos_update_request); */ void pm_qos_remove_request(struct pm_qos_request *req) { - struct pm_qos_object *o; - - if (req == NULL) + if (!req) /*guard against callers passing in null */ return; /* silent return to keep pcm code cleaner */ @@ -291,8 +303,9 @@ void pm_qos_remove_request(struct pm_qos_request *req) return; } - o = pm_qos_array[req->pm_qos_class]; - update_target(o, &req->node, 1, PM_QOS_DEFAULT_VALUE); + pm_qos_update_target(pm_qos_array[req->pm_qos_class]->constraints, + &req->node, PM_QOS_REMOVE_REQ, + PM_QOS_DEFAULT_VALUE); memset(req, 0, sizeof(*req)); } EXPORT_SYMBOL_GPL(pm_qos_remove_request); @@ -396,7 +409,6 @@ static ssize_t pm_qos_power_read(struct file *filp, char __user *buf, { s32 value; unsigned long flags; - struct pm_qos_object *o; struct pm_qos_request *req = filp->private_data; if (!req) @@ -404,9 +416,8 @@ static ssize_t pm_qos_power_read(struct file *filp, char __user *buf, if (!pm_qos_request_active(req)) return -EINVAL; - o = pm_qos_array[req->pm_qos_class]; spin_lock_irqsave(&pm_qos_lock, flags); - value = pm_qos_get_value(o); + value = pm_qos_get_value(pm_qos_array[req->pm_qos_class]->constraints); spin_unlock_irqrestore(&pm_qos_lock, flags); return simple_read_from_buffer(buf, count, f_pos, &value, sizeof(s32)); -- cgit v1.2.3-70-g09d2 From b66213cdb002b08b29603d488c451dfe25e2ca20 Mon Sep 17 00:00:00 2001 From: Jean Pihet Date: Thu, 25 Aug 2011 15:35:47 +0200 Subject: PM QoS: Add global notification mechanism for device constraints Add a global notification chain that gets called upon changes to the aggregated constraint value for any device. The notification callbacks are passing the full constraint request data in order for the callees to have access to it. The current use is for the platform low-level code to access the target device of the constraint. Signed-off-by: Jean Pihet Reviewed-by: Kevin Hilman Signed-off-by: Rafael J. Wysocki --- drivers/base/power/qos.c | 89 ++++++++++++++++++++++++++++++++++++++++-------- include/linux/pm_qos.h | 11 ++++++ kernel/power/qos.c | 2 +- 3 files changed, 87 insertions(+), 15 deletions(-) (limited to 'kernel') diff --git a/drivers/base/power/qos.c b/drivers/base/power/qos.c index cc4c541398a..8d0b81151c1 100644 --- a/drivers/base/power/qos.c +++ b/drivers/base/power/qos.c @@ -17,6 +17,12 @@ * * This QoS design is best effort based. Dependents register their QoS needs. * Watchers register to keep track of the current QoS needs of the system. + * Watchers can register different types of notification callbacks: + * . a per-device notification callback using the dev_pm_qos_*_notifier API. + * The notification chain data is stored in the per-device constraint + * data struct. + * . a system-wide notification callback using the dev_pm_qos_*_global_notifier + * API. The notification chain data is stored in a static variable. * * Note about the per-device constraint data struct allocation: * . The per-device constraints data struct ptr is tored into the device @@ -45,6 +51,36 @@ static DEFINE_MUTEX(dev_pm_qos_mtx); +static BLOCKING_NOTIFIER_HEAD(dev_pm_notifiers); + +/* + * apply_constraint + * @req: constraint request to apply + * @action: action to perform add/update/remove, of type enum pm_qos_req_action + * @value: defines the qos request + * + * Internal function to update the constraints list using the PM QoS core + * code and if needed call the per-device and the global notification + * callbacks + */ +static int apply_constraint(struct dev_pm_qos_request *req, + enum pm_qos_req_action action, int value) +{ + int ret, curr_value; + + ret = pm_qos_update_target(req->dev->power.constraints, + &req->node, action, value); + + if (ret) { + /* Call the global callbacks if needed */ + curr_value = pm_qos_read_value(req->dev->power.constraints); + blocking_notifier_call_chain(&dev_pm_notifiers, + (unsigned long)curr_value, + req); + } + + return ret; +} /* * dev_pm_qos_constraints_allocate @@ -111,12 +147,11 @@ void dev_pm_qos_constraints_destroy(struct device *dev) &dev->power.constraints->list, node) { /* - * Update constraints list and call the per-device + * Update constraints list and call the notification * callbacks if needed */ - pm_qos_update_target(req->dev->power.constraints, - &req->node, PM_QOS_REMOVE_REQ, - PM_QOS_DEFAULT_VALUE); + apply_constraint(req, PM_QOS_REMOVE_REQ, + PM_QOS_DEFAULT_VALUE); memset(req, 0, sizeof(*req)); } @@ -147,7 +182,7 @@ void dev_pm_qos_constraints_destroy(struct device *dev) * removed from the system */ int dev_pm_qos_add_request(struct device *dev, struct dev_pm_qos_request *req, - s32 value) + s32 value) { int ret = 0; @@ -178,8 +213,7 @@ int dev_pm_qos_add_request(struct device *dev, struct dev_pm_qos_request *req, ret = dev_pm_qos_constraints_allocate(dev); if (!ret) - ret = pm_qos_update_target(dev->power.constraints, &req->node, - PM_QOS_ADD_REQ, value); + ret = apply_constraint(req, PM_QOS_ADD_REQ, value); out: mutex_unlock(&dev_pm_qos_mtx); @@ -220,10 +254,8 @@ int dev_pm_qos_update_request(struct dev_pm_qos_request *req, if (req->dev->power.constraints_state == DEV_PM_QOS_ALLOCATED) { if (new_value != req->node.prio) - ret = pm_qos_update_target(req->dev->power.constraints, - &req->node, - PM_QOS_UPDATE_REQ, - new_value); + ret = apply_constraint(req, PM_QOS_UPDATE_REQ, + new_value); } else { /* Return if the device has been removed */ ret = -ENODEV; @@ -262,9 +294,8 @@ int dev_pm_qos_remove_request(struct dev_pm_qos_request *req) mutex_lock(&dev_pm_qos_mtx); if (req->dev->power.constraints_state == DEV_PM_QOS_ALLOCATED) { - ret = pm_qos_update_target(req->dev->power.constraints, - &req->node, PM_QOS_REMOVE_REQ, - PM_QOS_DEFAULT_VALUE); + ret = apply_constraint(req, PM_QOS_REMOVE_REQ, + PM_QOS_DEFAULT_VALUE); memset(req, 0, sizeof(*req)); } else { /* Return if the device has been removed */ @@ -336,3 +367,33 @@ out: return retval; } EXPORT_SYMBOL_GPL(dev_pm_qos_remove_notifier); + +/** + * dev_pm_qos_add_global_notifier - sets notification entry for changes to + * target value of the PM QoS constraints for any device + * + * @notifier: notifier block managed by caller. + * + * Will register the notifier into a notification chain that gets called + * upon changes to the target value for any device. + */ +int dev_pm_qos_add_global_notifier(struct notifier_block *notifier) +{ + return blocking_notifier_chain_register(&dev_pm_notifiers, notifier); +} +EXPORT_SYMBOL_GPL(dev_pm_qos_add_global_notifier); + +/** + * dev_pm_qos_remove_global_notifier - deletes notification for changes to + * target value of PM QoS constraints for any device + * + * @notifier: notifier block to be removed. + * + * Will remove the notifier from the notification chain that gets called + * upon changes to the target value for any device. + */ +int dev_pm_qos_remove_global_notifier(struct notifier_block *notifier) +{ + return blocking_notifier_chain_unregister(&dev_pm_notifiers, notifier); +} +EXPORT_SYMBOL_GPL(dev_pm_qos_remove_global_notifier); diff --git a/include/linux/pm_qos.h b/include/linux/pm_qos.h index f75f74dd9b9..ca7bd3f98cb 100644 --- a/include/linux/pm_qos.h +++ b/include/linux/pm_qos.h @@ -75,6 +75,7 @@ int pm_qos_request(int pm_qos_class); int pm_qos_add_notifier(int pm_qos_class, struct notifier_block *notifier); int pm_qos_remove_notifier(int pm_qos_class, struct notifier_block *notifier); int pm_qos_request_active(struct pm_qos_request *req); +s32 pm_qos_read_value(struct pm_qos_constraints *c); int dev_pm_qos_add_request(struct device *dev, struct dev_pm_qos_request *req, s32 value); @@ -84,6 +85,8 @@ int dev_pm_qos_add_notifier(struct device *dev, struct notifier_block *notifier); int dev_pm_qos_remove_notifier(struct device *dev, struct notifier_block *notifier); +int dev_pm_qos_add_global_notifier(struct notifier_block *notifier); +int dev_pm_qos_remove_global_notifier(struct notifier_block *notifier); void dev_pm_qos_constraints_init(struct device *dev); void dev_pm_qos_constraints_destroy(struct device *dev); #else @@ -111,6 +114,8 @@ static inline int pm_qos_remove_notifier(int pm_qos_class, { return 0; } static inline int pm_qos_request_active(struct pm_qos_request *req) { return 0; } +static inline s32 pm_qos_read_value(struct pm_qos_constraints *c) + { return 0; } static inline int dev_pm_qos_add_request(struct device *dev, struct dev_pm_qos_request *req, @@ -127,6 +132,12 @@ static inline int dev_pm_qos_add_notifier(struct device *dev, static inline int dev_pm_qos_remove_notifier(struct device *dev, struct notifier_block *notifier) { return 0; } +static inline int dev_pm_qos_add_global_notifier( + struct notifier_block *notifier) + { return 0; } +static inline int dev_pm_qos_remove_global_notifier( + struct notifier_block *notifier) + { return 0; } static inline void dev_pm_qos_constraints_init(struct device *dev) { return; } static inline void dev_pm_qos_constraints_destroy(struct device *dev) diff --git a/kernel/power/qos.c b/kernel/power/qos.c index 7c7cd181cab..1c1797dd1d1 100644 --- a/kernel/power/qos.c +++ b/kernel/power/qos.c @@ -140,7 +140,7 @@ static inline int pm_qos_get_value(struct pm_qos_constraints *c) } } -static inline s32 pm_qos_read_value(struct pm_qos_constraints *c) +s32 pm_qos_read_value(struct pm_qos_constraints *c) { return c->target_value; } -- cgit v1.2.3-70-g09d2