diff options
Diffstat (limited to 'drivers/cpuidle/sysfs.c')
| -rw-r--r-- | drivers/cpuidle/sysfs.c | 647 |
1 files changed, 647 insertions, 0 deletions
diff --git a/drivers/cpuidle/sysfs.c b/drivers/cpuidle/sysfs.c new file mode 100644 index 000000000..832a2c3f0 --- /dev/null +++ b/drivers/cpuidle/sysfs.c @@ -0,0 +1,647 @@ +/* + * sysfs.c - sysfs support + * + * (C) 2006-2007 Shaohua Li <shaohua.li@intel.com> + * + * This code is licenced under the GPL. + */ + +#include <linux/kernel.h> +#include <linux/cpuidle.h> +#include <linux/sysfs.h> +#include <linux/slab.h> +#include <linux/cpu.h> +#include <linux/completion.h> +#include <linux/capability.h> +#include <linux/device.h> +#include <linux/kobject.h> + +#include "cpuidle.h" + +static unsigned int sysfs_switch; +static int __init cpuidle_sysfs_setup(char *unused) +{ + sysfs_switch = 1; + return 1; +} +__setup("cpuidle_sysfs_switch", cpuidle_sysfs_setup); + +static ssize_t show_available_governors(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + ssize_t i = 0; + struct cpuidle_governor *tmp; + + mutex_lock(&cpuidle_lock); + list_for_each_entry(tmp, &cpuidle_governors, governor_list) { + if (i >= (ssize_t) ((PAGE_SIZE/sizeof(char)) - + CPUIDLE_NAME_LEN - 2)) + goto out; + i += scnprintf(&buf[i], CPUIDLE_NAME_LEN, "%s ", tmp->name); + } + +out: + i+= sprintf(&buf[i], "\n"); + mutex_unlock(&cpuidle_lock); + return i; +} + +static ssize_t show_current_driver(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + ssize_t ret; + struct cpuidle_driver *drv; + + spin_lock(&cpuidle_driver_lock); + drv = cpuidle_get_driver(); + if (drv) + ret = sprintf(buf, "%s\n", drv->name); + else + ret = sprintf(buf, "none\n"); + spin_unlock(&cpuidle_driver_lock); + + return ret; +} + +static ssize_t show_current_governor(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + ssize_t ret; + + mutex_lock(&cpuidle_lock); + if (cpuidle_curr_governor) + ret = sprintf(buf, "%s\n", cpuidle_curr_governor->name); + else + ret = sprintf(buf, "none\n"); + mutex_unlock(&cpuidle_lock); + + return ret; +} + +static ssize_t store_current_governor(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + char gov_name[CPUIDLE_NAME_LEN]; + int ret = -EINVAL; + size_t len = count; + struct cpuidle_governor *gov; + + if (!len || len >= sizeof(gov_name)) + return -EINVAL; + + memcpy(gov_name, buf, len); + gov_name[len] = '\0'; + if (gov_name[len - 1] == '\n') + gov_name[--len] = '\0'; + + mutex_lock(&cpuidle_lock); + + list_for_each_entry(gov, &cpuidle_governors, governor_list) { + if (strlen(gov->name) == len && !strcmp(gov->name, gov_name)) { + ret = cpuidle_switch_governor(gov); + break; + } + } + + mutex_unlock(&cpuidle_lock); + + if (ret) + return ret; + else + return count; +} + +static DEVICE_ATTR(current_driver, 0444, show_current_driver, NULL); +static DEVICE_ATTR(current_governor_ro, 0444, show_current_governor, NULL); + +static struct attribute *cpuidle_default_attrs[] = { + &dev_attr_current_driver.attr, + &dev_attr_current_governor_ro.attr, + NULL +}; + +static DEVICE_ATTR(available_governors, 0444, show_available_governors, NULL); +static DEVICE_ATTR(current_governor, 0644, show_current_governor, + store_current_governor); + +static struct attribute *cpuidle_switch_attrs[] = { + &dev_attr_available_governors.attr, + &dev_attr_current_driver.attr, + &dev_attr_current_governor.attr, + NULL +}; + +static struct attribute_group cpuidle_attr_group = { + .attrs = cpuidle_default_attrs, + .name = "cpuidle", +}; + +/** + * cpuidle_add_interface - add CPU global sysfs attributes + */ +int cpuidle_add_interface(struct device *dev) +{ + if (sysfs_switch) + cpuidle_attr_group.attrs = cpuidle_switch_attrs; + + return sysfs_create_group(&dev->kobj, &cpuidle_attr_group); +} + +/** + * cpuidle_remove_interface - remove CPU global sysfs attributes + */ +void cpuidle_remove_interface(struct device *dev) +{ + sysfs_remove_group(&dev->kobj, &cpuidle_attr_group); +} + +struct cpuidle_attr { + struct attribute attr; + ssize_t (*show)(struct cpuidle_device *, char *); + ssize_t (*store)(struct cpuidle_device *, const char *, size_t count); +}; + +#define define_one_ro(_name, show) \ + static struct cpuidle_attr attr_##_name = __ATTR(_name, 0444, show, NULL) +#define define_one_rw(_name, show, store) \ + static struct cpuidle_attr attr_##_name = __ATTR(_name, 0644, show, store) + +#define attr_to_cpuidleattr(a) container_of(a, struct cpuidle_attr, attr) + +struct cpuidle_device_kobj { + struct cpuidle_device *dev; + struct completion kobj_unregister; + struct kobject kobj; +}; + +static inline struct cpuidle_device *to_cpuidle_device(struct kobject *kobj) +{ + struct cpuidle_device_kobj *kdev = + container_of(kobj, struct cpuidle_device_kobj, kobj); + + return kdev->dev; +} + +static ssize_t cpuidle_show(struct kobject *kobj, struct attribute *attr, + char *buf) +{ + int ret = -EIO; + struct cpuidle_device *dev = to_cpuidle_device(kobj); + struct cpuidle_attr *cattr = attr_to_cpuidleattr(attr); + + if (cattr->show) { + mutex_lock(&cpuidle_lock); + ret = cattr->show(dev, buf); + mutex_unlock(&cpuidle_lock); + } + return ret; +} + +static ssize_t cpuidle_store(struct kobject *kobj, struct attribute *attr, + const char *buf, size_t count) +{ + int ret = -EIO; + struct cpuidle_device *dev = to_cpuidle_device(kobj); + struct cpuidle_attr *cattr = attr_to_cpuidleattr(attr); + + if (cattr->store) { + mutex_lock(&cpuidle_lock); + ret = cattr->store(dev, buf, count); + mutex_unlock(&cpuidle_lock); + } + return ret; +} + +static const struct sysfs_ops cpuidle_sysfs_ops = { + .show = cpuidle_show, + .store = cpuidle_store, +}; + +static void cpuidle_sysfs_release(struct kobject *kobj) +{ + struct cpuidle_device_kobj *kdev = + container_of(kobj, struct cpuidle_device_kobj, kobj); + + complete(&kdev->kobj_unregister); +} + +static struct kobj_type ktype_cpuidle = { + .sysfs_ops = &cpuidle_sysfs_ops, + .release = cpuidle_sysfs_release, +}; + +struct cpuidle_state_attr { + struct attribute attr; + ssize_t (*show)(struct cpuidle_state *, \ + struct cpuidle_state_usage *, char *); + ssize_t (*store)(struct cpuidle_state *, \ + struct cpuidle_state_usage *, const char *, size_t); +}; + +#define define_one_state_ro(_name, show) \ +static struct cpuidle_state_attr attr_##_name = __ATTR(_name, 0444, show, NULL) + +#define define_one_state_rw(_name, show, store) \ +static struct cpuidle_state_attr attr_##_name = __ATTR(_name, 0644, show, store) + +#define define_show_state_function(_name) \ +static ssize_t show_state_##_name(struct cpuidle_state *state, \ + struct cpuidle_state_usage *state_usage, char *buf) \ +{ \ + return sprintf(buf, "%u\n", state->_name);\ +} + +#define define_store_state_ull_function(_name) \ +static ssize_t store_state_##_name(struct cpuidle_state *state, \ + struct cpuidle_state_usage *state_usage, \ + const char *buf, size_t size) \ +{ \ + unsigned long long value; \ + int err; \ + if (!capable(CAP_SYS_ADMIN)) \ + return -EPERM; \ + err = kstrtoull(buf, 0, &value); \ + if (err) \ + return err; \ + if (value) \ + state_usage->_name = 1; \ + else \ + state_usage->_name = 0; \ + return size; \ +} + +#define define_show_state_ull_function(_name) \ +static ssize_t show_state_##_name(struct cpuidle_state *state, \ + struct cpuidle_state_usage *state_usage, \ + char *buf) \ +{ \ + return sprintf(buf, "%llu\n", state_usage->_name);\ +} + +#define define_show_state_str_function(_name) \ +static ssize_t show_state_##_name(struct cpuidle_state *state, \ + struct cpuidle_state_usage *state_usage, \ + char *buf) \ +{ \ + if (state->_name[0] == '\0')\ + return sprintf(buf, "<null>\n");\ + return sprintf(buf, "%s\n", state->_name);\ +} + +define_show_state_function(exit_latency) +define_show_state_function(target_residency) +define_show_state_function(power_usage) +define_show_state_ull_function(usage) +define_show_state_ull_function(time) +define_show_state_str_function(name) +define_show_state_str_function(desc) +define_show_state_ull_function(disable) +define_store_state_ull_function(disable) + +define_one_state_ro(name, show_state_name); +define_one_state_ro(desc, show_state_desc); +define_one_state_ro(latency, show_state_exit_latency); +define_one_state_ro(residency, show_state_target_residency); +define_one_state_ro(power, show_state_power_usage); +define_one_state_ro(usage, show_state_usage); +define_one_state_ro(time, show_state_time); +define_one_state_rw(disable, show_state_disable, store_state_disable); + +static struct attribute *cpuidle_state_default_attrs[] = { + &attr_name.attr, + &attr_desc.attr, + &attr_latency.attr, + &attr_residency.attr, + &attr_power.attr, + &attr_usage.attr, + &attr_time.attr, + &attr_disable.attr, + NULL +}; + +struct cpuidle_state_kobj { + struct cpuidle_state *state; + struct cpuidle_state_usage *state_usage; + struct completion kobj_unregister; + struct kobject kobj; +}; + +#define kobj_to_state_obj(k) container_of(k, struct cpuidle_state_kobj, kobj) +#define kobj_to_state(k) (kobj_to_state_obj(k)->state) +#define kobj_to_state_usage(k) (kobj_to_state_obj(k)->state_usage) +#define attr_to_stateattr(a) container_of(a, struct cpuidle_state_attr, attr) + +static ssize_t cpuidle_state_show(struct kobject *kobj, struct attribute *attr, + char * buf) +{ + int ret = -EIO; + struct cpuidle_state *state = kobj_to_state(kobj); + struct cpuidle_state_usage *state_usage = kobj_to_state_usage(kobj); + struct cpuidle_state_attr * cattr = attr_to_stateattr(attr); + + if (cattr->show) + ret = cattr->show(state, state_usage, buf); + + return ret; +} + +static ssize_t cpuidle_state_store(struct kobject *kobj, struct attribute *attr, + const char *buf, size_t size) +{ + int ret = -EIO; + struct cpuidle_state *state = kobj_to_state(kobj); + struct cpuidle_state_usage *state_usage = kobj_to_state_usage(kobj); + struct cpuidle_state_attr *cattr = attr_to_stateattr(attr); + + if (cattr->store) + ret = cattr->store(state, state_usage, buf, size); + + return ret; +} + +static const struct sysfs_ops cpuidle_state_sysfs_ops = { + .show = cpuidle_state_show, + .store = cpuidle_state_store, +}; + +static void cpuidle_state_sysfs_release(struct kobject *kobj) +{ + struct cpuidle_state_kobj *state_obj = kobj_to_state_obj(kobj); + + complete(&state_obj->kobj_unregister); +} + +static struct kobj_type ktype_state_cpuidle = { + .sysfs_ops = &cpuidle_state_sysfs_ops, + .default_attrs = cpuidle_state_default_attrs, + .release = cpuidle_state_sysfs_release, +}; + +static inline void cpuidle_free_state_kobj(struct cpuidle_device *device, int i) +{ + kobject_put(&device->kobjs[i]->kobj); + wait_for_completion(&device->kobjs[i]->kobj_unregister); + kfree(device->kobjs[i]); + device->kobjs[i] = NULL; +} + +/** + * cpuidle_add_state_sysfs - adds cpuidle states sysfs attributes + * @device: the target device + */ +static int cpuidle_add_state_sysfs(struct cpuidle_device *device) +{ + int i, ret = -ENOMEM; + struct cpuidle_state_kobj *kobj; + struct cpuidle_device_kobj *kdev = device->kobj_dev; + struct cpuidle_driver *drv = cpuidle_get_cpu_driver(device); + + /* state statistics */ + for (i = 0; i < drv->state_count; i++) { + kobj = kzalloc(sizeof(struct cpuidle_state_kobj), GFP_KERNEL); + if (!kobj) + goto error_state; + kobj->state = &drv->states[i]; + kobj->state_usage = &device->states_usage[i]; + init_completion(&kobj->kobj_unregister); + + ret = kobject_init_and_add(&kobj->kobj, &ktype_state_cpuidle, + &kdev->kobj, "state%d", i); + if (ret) { + kfree(kobj); + goto error_state; + } + kobject_uevent(&kobj->kobj, KOBJ_ADD); + device->kobjs[i] = kobj; + } + + return 0; + +error_state: + for (i = i - 1; i >= 0; i--) + cpuidle_free_state_kobj(device, i); + return ret; +} + +/** + * cpuidle_remove_driver_sysfs - removes the cpuidle states sysfs attributes + * @device: the target device + */ +static void cpuidle_remove_state_sysfs(struct cpuidle_device *device) +{ + struct cpuidle_driver *drv = cpuidle_get_cpu_driver(device); + int i; + + for (i = 0; i < drv->state_count; i++) + cpuidle_free_state_kobj(device, i); +} + +#ifdef CONFIG_CPU_IDLE_MULTIPLE_DRIVERS +#define kobj_to_driver_kobj(k) container_of(k, struct cpuidle_driver_kobj, kobj) +#define attr_to_driver_attr(a) container_of(a, struct cpuidle_driver_attr, attr) + +#define define_one_driver_ro(_name, show) \ + static struct cpuidle_driver_attr attr_driver_##_name = \ + __ATTR(_name, 0444, show, NULL) + +struct cpuidle_driver_kobj { + struct cpuidle_driver *drv; + struct completion kobj_unregister; + struct kobject kobj; +}; + +struct cpuidle_driver_attr { + struct attribute attr; + ssize_t (*show)(struct cpuidle_driver *, char *); + ssize_t (*store)(struct cpuidle_driver *, const char *, size_t); +}; + +static ssize_t show_driver_name(struct cpuidle_driver *drv, char *buf) +{ + ssize_t ret; + + spin_lock(&cpuidle_driver_lock); + ret = sprintf(buf, "%s\n", drv ? drv->name : "none"); + spin_unlock(&cpuidle_driver_lock); + + return ret; +} + +static void cpuidle_driver_sysfs_release(struct kobject *kobj) +{ + struct cpuidle_driver_kobj *driver_kobj = kobj_to_driver_kobj(kobj); + complete(&driver_kobj->kobj_unregister); +} + +static ssize_t cpuidle_driver_show(struct kobject *kobj, struct attribute *attr, + char *buf) +{ + int ret = -EIO; + struct cpuidle_driver_kobj *driver_kobj = kobj_to_driver_kobj(kobj); + struct cpuidle_driver_attr *dattr = attr_to_driver_attr(attr); + + if (dattr->show) + ret = dattr->show(driver_kobj->drv, buf); + + return ret; +} + +static ssize_t cpuidle_driver_store(struct kobject *kobj, struct attribute *attr, + const char *buf, size_t size) +{ + int ret = -EIO; + struct cpuidle_driver_kobj *driver_kobj = kobj_to_driver_kobj(kobj); + struct cpuidle_driver_attr *dattr = attr_to_driver_attr(attr); + + if (dattr->store) + ret = dattr->store(driver_kobj->drv, buf, size); + + return ret; +} + +define_one_driver_ro(name, show_driver_name); + +static const struct sysfs_ops cpuidle_driver_sysfs_ops = { + .show = cpuidle_driver_show, + .store = cpuidle_driver_store, +}; + +static struct attribute *cpuidle_driver_default_attrs[] = { + &attr_driver_name.attr, + NULL +}; + +static struct kobj_type ktype_driver_cpuidle = { + .sysfs_ops = &cpuidle_driver_sysfs_ops, + .default_attrs = cpuidle_driver_default_attrs, + .release = cpuidle_driver_sysfs_release, +}; + +/** + * cpuidle_add_driver_sysfs - adds the driver name sysfs attribute + * @device: the target device + */ +static int cpuidle_add_driver_sysfs(struct cpuidle_device *dev) +{ + struct cpuidle_driver_kobj *kdrv; + struct cpuidle_device_kobj *kdev = dev->kobj_dev; + struct cpuidle_driver *drv = cpuidle_get_cpu_driver(dev); + int ret; + + kdrv = kzalloc(sizeof(*kdrv), GFP_KERNEL); + if (!kdrv) + return -ENOMEM; + + kdrv->drv = drv; + init_completion(&kdrv->kobj_unregister); + + ret = kobject_init_and_add(&kdrv->kobj, &ktype_driver_cpuidle, + &kdev->kobj, "driver"); + if (ret) { + kfree(kdrv); + return ret; + } + + kobject_uevent(&kdrv->kobj, KOBJ_ADD); + dev->kobj_driver = kdrv; + + return ret; +} + +/** + * cpuidle_remove_driver_sysfs - removes the driver name sysfs attribute + * @device: the target device + */ +static void cpuidle_remove_driver_sysfs(struct cpuidle_device *dev) +{ + struct cpuidle_driver_kobj *kdrv = dev->kobj_driver; + kobject_put(&kdrv->kobj); + wait_for_completion(&kdrv->kobj_unregister); + kfree(kdrv); +} +#else +static inline int cpuidle_add_driver_sysfs(struct cpuidle_device *dev) +{ + return 0; +} + +static inline void cpuidle_remove_driver_sysfs(struct cpuidle_device *dev) +{ + ; +} +#endif + +/** + * cpuidle_add_device_sysfs - adds device specific sysfs attributes + * @device: the target device + */ +int cpuidle_add_device_sysfs(struct cpuidle_device *device) +{ + int ret; + + ret = cpuidle_add_state_sysfs(device); + if (ret) + return ret; + + ret = cpuidle_add_driver_sysfs(device); + if (ret) + cpuidle_remove_state_sysfs(device); + return ret; +} + +/** + * cpuidle_remove_device_sysfs : removes device specific sysfs attributes + * @device : the target device + */ +void cpuidle_remove_device_sysfs(struct cpuidle_device *device) +{ + cpuidle_remove_driver_sysfs(device); + cpuidle_remove_state_sysfs(device); +} + +/** + * cpuidle_add_sysfs - creates a sysfs instance for the target device + * @dev: the target device + */ +int cpuidle_add_sysfs(struct cpuidle_device *dev) +{ + struct cpuidle_device_kobj *kdev; + struct device *cpu_dev = get_cpu_device((unsigned long)dev->cpu); + int error; + + kdev = kzalloc(sizeof(*kdev), GFP_KERNEL); + if (!kdev) + return -ENOMEM; + kdev->dev = dev; + dev->kobj_dev = kdev; + + init_completion(&kdev->kobj_unregister); + + error = kobject_init_and_add(&kdev->kobj, &ktype_cpuidle, &cpu_dev->kobj, + "cpuidle"); + if (error) { + kfree(kdev); + return error; + } + + kobject_uevent(&kdev->kobj, KOBJ_ADD); + + return 0; +} + +/** + * cpuidle_remove_sysfs - deletes a sysfs instance on the target device + * @dev: the target device + */ +void cpuidle_remove_sysfs(struct cpuidle_device *dev) +{ + struct cpuidle_device_kobj *kdev = dev->kobj_dev; + + kobject_put(&kdev->kobj); + wait_for_completion(&kdev->kobj_unregister); + kfree(kdev); +} |