linux/drivers/cpuidle/sysfs.c
Yi Yang 8b78cf602f cpuidle: fix cpuidle time and usage overflow
cpuidle C-state sysfs node time and usage are very easy to overflow because
they are all of unsigned int type, time will overflow within about two hours,
usage will take longer time to overflow, but they are increasing for ever.

This patch will convert them to unsigned long long.

Signed-off-by: Yi Yang <yi.y.yang@intel.com>
Acked-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2008-03-26 00:45:26 -04:00

377 lines
9.3 KiB
C

/*
* 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/cpu.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 sys_device *dev, 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 sys_device *dev, char *buf)
{
ssize_t ret;
spin_lock(&cpuidle_driver_lock);
if (cpuidle_curr_driver)
ret = sprintf(buf, "%s\n", cpuidle_curr_driver->name);
else
ret = sprintf(buf, "none\n");
spin_unlock(&cpuidle_driver_lock);
return ret;
}
static ssize_t show_current_governor(struct sys_device *dev, 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 sys_device *dev,
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 SYSDEV_ATTR(current_driver, 0444, show_current_driver, NULL);
static SYSDEV_ATTR(current_governor_ro, 0444, show_current_governor, NULL);
static struct attribute *cpuclass_default_attrs[] = {
&attr_current_driver.attr,
&attr_current_governor_ro.attr,
NULL
};
static SYSDEV_ATTR(available_governors, 0444, show_available_governors, NULL);
static SYSDEV_ATTR(current_governor, 0644, show_current_governor,
store_current_governor);
static struct attribute *cpuclass_switch_attrs[] = {
&attr_available_governors.attr,
&attr_current_driver.attr,
&attr_current_governor.attr,
NULL
};
static struct attribute_group cpuclass_attr_group = {
.attrs = cpuclass_default_attrs,
.name = "cpuidle",
};
/**
* cpuidle_add_class_sysfs - add CPU global sysfs attributes
*/
int cpuidle_add_class_sysfs(struct sysdev_class *cls)
{
if (sysfs_switch)
cpuclass_attr_group.attrs = cpuclass_switch_attrs;
return sysfs_create_group(&cls->kset.kobj, &cpuclass_attr_group);
}
/**
* cpuidle_remove_class_sysfs - remove CPU global sysfs attributes
*/
void cpuidle_remove_class_sysfs(struct sysdev_class *cls)
{
sysfs_remove_group(&cls->kset.kobj, &cpuclass_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 kobj_to_cpuidledev(k) container_of(k, struct cpuidle_device, kobj)
#define attr_to_cpuidleattr(a) container_of(a, struct cpuidle_attr, attr)
static ssize_t cpuidle_show(struct kobject * kobj, struct attribute * attr ,char * buf)
{
int ret = -EIO;
struct cpuidle_device *dev = kobj_to_cpuidledev(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 = kobj_to_cpuidledev(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 struct sysfs_ops cpuidle_sysfs_ops = {
.show = cpuidle_show,
.store = cpuidle_store,
};
static void cpuidle_sysfs_release(struct kobject *kobj)
{
struct cpuidle_device *dev = kobj_to_cpuidledev(kobj);
complete(&dev->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 *, char *);
ssize_t (*store)(struct cpuidle_state *, 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_show_state_function(_name) \
static ssize_t show_state_##_name(struct cpuidle_state *state, 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, char *buf) \
{ \
return sprintf(buf, "%llu\n", state->_name);\
}
#define define_show_state_str_function(_name) \
static ssize_t show_state_##_name(struct cpuidle_state *state, 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(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_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(power, show_state_power_usage);
define_one_state_ro(usage, show_state_usage);
define_one_state_ro(time, show_state_time);
static struct attribute *cpuidle_state_default_attrs[] = {
&attr_name.attr,
&attr_desc.attr,
&attr_latency.attr,
&attr_power.attr,
&attr_usage.attr,
&attr_time.attr,
NULL
};
#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 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_attr * cattr = attr_to_stateattr(attr);
if (cattr->show)
ret = cattr->show(state, buf);
return ret;
}
static struct sysfs_ops cpuidle_state_sysfs_ops = {
.show = cpuidle_state_show,
};
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 void inline 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_driver_sysfs - adds driver-specific sysfs attributes
* @device: the target device
*/
int cpuidle_add_state_sysfs(struct cpuidle_device *device)
{
int i, ret = -ENOMEM;
struct cpuidle_state_kobj *kobj;
/* state statistics */
for (i = 0; i < device->state_count; i++) {
kobj = kzalloc(sizeof(struct cpuidle_state_kobj), GFP_KERNEL);
if (!kobj)
goto error_state;
kobj->state = &device->states[i];
init_completion(&kobj->kobj_unregister);
ret = kobject_init_and_add(&kobj->kobj, &ktype_state_cpuidle, &device->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 driver-specific sysfs attributes
* @device: the target device
*/
void cpuidle_remove_state_sysfs(struct cpuidle_device *device)
{
int i;
for (i = 0; i < device->state_count; i++)
cpuidle_free_state_kobj(device, i);
}
/**
* cpuidle_add_sysfs - creates a sysfs instance for the target device
* @sysdev: the target device
*/
int cpuidle_add_sysfs(struct sys_device *sysdev)
{
int cpu = sysdev->id;
struct cpuidle_device *dev;
int error;
dev = per_cpu(cpuidle_devices, cpu);
error = kobject_init_and_add(&dev->kobj, &ktype_cpuidle, &sysdev->kobj,
"cpuidle");
if (!error)
kobject_uevent(&dev->kobj, KOBJ_ADD);
return error;
}
/**
* cpuidle_remove_sysfs - deletes a sysfs instance on the target device
* @sysdev: the target device
*/
void cpuidle_remove_sysfs(struct sys_device *sysdev)
{
int cpu = sysdev->id;
struct cpuidle_device *dev;
dev = per_cpu(cpuidle_devices, cpu);
kobject_put(&dev->kobj);
}