/*
* sysfs.c - sysfs support
*
* (C) 2006-2007 Shaohua Li <[email protected]>
*
* 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 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 - (CPUIDLE_NAME_LEN + 2)))
goto out;
i += scnprintf(&buf[i], CPUIDLE_NAME_LEN + 1, "%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 + 1];
int ret;
struct cpuidle_governor *gov;
ret = sscanf(buf, "%" __stringify(CPUIDLE_NAME_LEN) "s", gov_name);
if (ret != 1)
return -EINVAL;
mutex_lock(&cpuidle_lock);
ret = -EINVAL;
list_for_each_entry(gov, &cpuidle_governors, governor_list) {
if (!strncmp(gov->name, gov_name, CPUIDLE_NAME_LEN)) {
ret = cpuidle_switch_governor(gov);
break;
}
}
mutex_unlock(&cpuidle_lock);
return ret ? ret : count;
}
static DEVICE_ATTR(available_governors, 0444, show_available_governors, NULL);
static DEVICE_ATTR(current_driver, 0444, show_current_driver, NULL);
static DEVICE_ATTR(current_governor, 0644, show_current_governor,
store_current_governor);
static DEVICE_ATTR(current_governor_ro, 0444, show_current_governor, NULL);
static struct attribute *cpuidle_attrs[] = {
&dev_attr_available_governors.attr,
&dev_attr_current_driver.attr,
&dev_attr_current_governor.attr,
&dev_attr_current_governor_ro.attr,
NULL
};
static struct attribute_group cpuidle_attr_group = {
.attrs = cpuidle_attrs,
.name = "cpuidle",
};
/**
* cpuidle_add_interface - add CPU global sysfs attributes
*/
int cpuidle_add_interface(void)
{
struct device *dev_root = bus_get_dev_root(&cpu_subsys);
int retval;
if (!dev_root)
return -EINVAL;
retval = sysfs_create_group(&dev_root->kobj, &cpuidle_attr_group);
put_device(dev_root);
return retval;
}
/**
* cpuidle_remove_interface - remove CPU global sysfs attributes
* @dev: the target device
*/
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 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 const 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_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 define_show_state_time_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", ktime_to_us(state->_name##_ns)); \
}
define_show_state_time_function(exit_latency)
define_show_state_time_function(target_residency)
define_show_state_function(power_usage)
define_show_state_ull_function(usage)
define_show_state_ull_function(rejected)
define_show_state_str_function(name)
define_show_state_str_function(desc)
define_show_state_ull_function(above)
define_show_state_ull_function(below)
static ssize_t show_state_time(struct cpuidle_state *state,
struct cpuidle_state_usage *state_usage,
char *buf)
{
return sprintf(buf, "%llu\n", ktime_to_us(state_usage->time_ns));
}
static ssize_t show_state_disable(struct cpuidle_state *state,
struct cpuidle_state_usage *state_usage,
char *buf)
{
return sprintf(buf, "%llu\n",
state_usage->disable & CPUIDLE_STATE_DISABLED_BY_USER);
}
static ssize_t store_state_disable(struct cpuidle_state *state,
struct cpuidle_state_usage *state_usage,
const char *buf, size_t size)
{
unsigned int value;
int err;
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
err = kstrtouint(buf, 0, &value);
if (err)
return err;
if (value)
state_usage->disable |= CPUIDLE_STATE_DISABLED_BY_USER;
else
state_usage->disable &= ~CPUIDLE_STATE_DISABLED_BY_USER;
return size;
}
static ssize_t show_state_default_status(struct cpuidle_state *state,
struct cpuidle_state_usage *state_usage,
char *buf)
{
return sprintf(buf, "%s\n",
state->flags & CPUIDLE_FLAG_OFF ? "disabled" : "enabled");
}
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(rejected, show_state_rejected);
define_one_state_ro(time, show_state_time);
define_one_state_rw(disable, show_state_disable, store_state_disable);
define_one_state_ro(above, show_state_above);
define_one_state_ro(below, show_state_below);
define_one_state_ro(default_status, show_state_default_status);
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_rejected.attr,
&attr_time.attr,
&attr_disable.attr,
&attr_above.attr,
&attr_below.attr,
&attr_default_status.attr,
NULL
};
ATTRIBUTE_GROUPS(cpuidle_state_default);
struct cpuidle_state_kobj {
struct cpuidle_state *state;
struct cpuidle_state_usage *state_usage;
struct completion kobj_unregister;
struct kobject kobj;
struct cpuidle_device *device;
};
#ifdef CONFIG_SUSPEND
#define define_show_state_s2idle_ull_function(_name) \
static ssize_t show_state_s2idle_##_name(struct cpuidle_state *state, \
struct cpuidle_state_usage *state_usage, \
char *buf) \
{ \
return sprintf(buf, "%llu\n", state_usage->s2idle_##_name);\
}
define_show_state_s2idle_ull_function(usage);
define_show_state_s2idle_ull_function(time);
#define define_one_state_s2idle_ro(_name, show) \
static struct cpuidle_state_attr attr_s2idle_##_name = \
__ATTR(_name, 0444, show, NULL)
define_one_state_s2idle_ro(usage, show_state_s2idle_usage);
define_one_state_s2idle_ro(time, show_state_s2idle_time);
static struct attribute *cpuidle_state_s2idle_attrs[] = {
&attr_s2idle_usage.attr,
&attr_s2idle_time.attr,
NULL
};
static const struct attribute_group cpuidle_state_s2idle_group = {
.name = "s2idle",
.attrs = cpuidle_state_s2idle_attrs,
};
static void cpuidle_add_s2idle_attr_group(struct cpuidle_state_kobj *kobj)
{
int ret;
if (!kobj->state->enter_s2idle)
return;
ret = sysfs_create_group(&kobj->kobj, &cpuidle_state_s2idle_group);
if (ret)
pr_debug("%s: sysfs attribute group not created\n", __func__);
}
static void cpuidle_remove_s2idle_attr_group(struct cpuidle_state_kobj *kobj)
{
if (kobj->state->enter_s2idle)
sysfs_remove_group(&kobj->kobj, &cpuidle_state_s2idle_group);
}
#else
static inline void cpuidle_add_s2idle_attr_group(struct cpuidle_state_kobj *kobj) { }
static inline void cpuidle_remove_s2idle_attr_group(struct cpuidle_state_kobj *kobj) { }
#endif /* CONFIG_SUSPEND */
#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 kobj_to_device(k) (kobj_to_state_obj(k)->device)
#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);
struct cpuidle_device *dev = kobj_to_device(kobj);
if (cattr->store)
ret = cattr->store(state, state_usage, buf, size);
/* reset poll time cache */
dev->poll_limit_ns = 0;
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 const struct kobj_type ktype_state_cpuidle = {
.sysfs_ops = &cpuidle_state_sysfs_ops,
.default_groups = cpuidle_state_default_groups,
.release = cpuidle_state_sysfs_release,
};
static inline void cpuidle_free_state_kobj(struct cpuidle_device *device, int i)
{
cpuidle_remove_s2idle_attr_group(device->kobjs[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) {
ret = -ENOMEM;
goto error_state;
}
kobj->state = &drv->states[i];
kobj->state_usage = &device->states_usage[i];
kobj->device = device;
init_completion(&kobj->kobj_unregister);
ret = kobject_init_and_add(&kobj->kobj, &ktype_state_cpuidle,
&kdev->kobj, "state%d", i);
if (ret) {
kobject_put(&kobj->kobj);
kfree(kobj);
goto error_state;
}
cpuidle_add_s2idle_attr_group(kobj);
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_state_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
};
ATTRIBUTE_GROUPS(cpuidle_driver_default);
static const struct kobj_type ktype_driver_cpuidle = {
.sysfs_ops = &cpuidle_driver_sysfs_ops,
.default_groups = cpuidle_driver_default_groups,
.release = cpuidle_driver_sysfs_release,
};
/**
* cpuidle_add_driver_sysfs - adds the driver name sysfs attribute
* @dev: 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) {
kobject_put(&kdrv->kobj);
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
* @dev: 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;
/*
* Return if cpu_device is not setup for this CPU.
*
* This could happen if the arch did not set up cpu_device
* since this CPU is not in cpu_present mask and the
* driver did not send a correct CPU mask during registration.
* Without this check we would end up passing bogus
* value for &cpu_dev->kobj in kobject_init_and_add()
*/
if (!cpu_dev)
return -ENODEV;
kdev = kzalloc(sizeof(*kdev), GFP_KERNEL);
if (!kdev)
return -ENOMEM;
kdev->dev = dev;
init_completion(&kdev->kobj_unregister);
error = kobject_init_and_add(&kdev->kobj, &ktype_cpuidle, &cpu_dev->kobj,
"cpuidle");
if (error) {
kobject_put(&kdev->kobj);
kfree(kdev);
return error;
}
dev->kobj_dev = kdev;
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);
}
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