linux-stable/include/linux/cpuidle.h
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

190 lines
4.9 KiB
C

/*
* cpuidle.h - a generic framework for CPU idle power management
*
* (C) 2007 Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
* Shaohua Li <shaohua.li@intel.com>
* Adam Belay <abelay@novell.com>
*
* This code is licenced under the GPL.
*/
#ifndef _LINUX_CPUIDLE_H
#define _LINUX_CPUIDLE_H
#include <linux/percpu.h>
#include <linux/list.h>
#include <linux/module.h>
#include <linux/kobject.h>
#include <linux/completion.h>
#define CPUIDLE_STATE_MAX 8
#define CPUIDLE_NAME_LEN 16
#define CPUIDLE_DESC_LEN 32
struct cpuidle_device;
/****************************
* CPUIDLE DEVICE INTERFACE *
****************************/
struct cpuidle_state {
char name[CPUIDLE_NAME_LEN];
char desc[CPUIDLE_DESC_LEN];
void *driver_data;
unsigned int flags;
unsigned int exit_latency; /* in US */
unsigned int power_usage; /* in mW */
unsigned int target_residency; /* in US */
unsigned long long usage;
unsigned long long time; /* in US */
int (*enter) (struct cpuidle_device *dev,
struct cpuidle_state *state);
};
/* Idle State Flags */
#define CPUIDLE_FLAG_TIME_VALID (0x01) /* is residency time measurable? */
#define CPUIDLE_FLAG_CHECK_BM (0x02) /* BM activity will exit state */
#define CPUIDLE_FLAG_POLL (0x10) /* no latency, no savings */
#define CPUIDLE_FLAG_SHALLOW (0x20) /* low latency, minimal savings */
#define CPUIDLE_FLAG_BALANCED (0x40) /* medium latency, moderate savings */
#define CPUIDLE_FLAG_DEEP (0x80) /* high latency, large savings */
#define CPUIDLE_DRIVER_FLAGS_MASK (0xFFFF0000)
/**
* cpuidle_get_statedata - retrieves private driver state data
* @state: the state
*/
static inline void * cpuidle_get_statedata(struct cpuidle_state *state)
{
return state->driver_data;
}
/**
* cpuidle_set_statedata - stores private driver state data
* @state: the state
* @data: the private data
*/
static inline void
cpuidle_set_statedata(struct cpuidle_state *state, void *data)
{
state->driver_data = data;
}
struct cpuidle_state_kobj {
struct cpuidle_state *state;
struct completion kobj_unregister;
struct kobject kobj;
};
struct cpuidle_device {
unsigned int enabled:1;
unsigned int cpu;
int last_residency;
int state_count;
struct cpuidle_state states[CPUIDLE_STATE_MAX];
struct cpuidle_state_kobj *kobjs[CPUIDLE_STATE_MAX];
struct cpuidle_state *last_state;
struct list_head device_list;
struct kobject kobj;
struct completion kobj_unregister;
void *governor_data;
struct cpuidle_state *safe_state;
};
DECLARE_PER_CPU(struct cpuidle_device *, cpuidle_devices);
/**
* cpuidle_get_last_residency - retrieves the last state's residency time
* @dev: the target CPU
*
* NOTE: this value is invalid if CPUIDLE_FLAG_TIME_VALID isn't set
*/
static inline int cpuidle_get_last_residency(struct cpuidle_device *dev)
{
return dev->last_residency;
}
/****************************
* CPUIDLE DRIVER INTERFACE *
****************************/
struct cpuidle_driver {
char name[CPUIDLE_NAME_LEN];
struct module *owner;
};
#ifdef CONFIG_CPU_IDLE
extern int cpuidle_register_driver(struct cpuidle_driver *drv);
extern void cpuidle_unregister_driver(struct cpuidle_driver *drv);
extern int cpuidle_register_device(struct cpuidle_device *dev);
extern void cpuidle_unregister_device(struct cpuidle_device *dev);
extern void cpuidle_pause_and_lock(void);
extern void cpuidle_resume_and_unlock(void);
extern int cpuidle_enable_device(struct cpuidle_device *dev);
extern void cpuidle_disable_device(struct cpuidle_device *dev);
#else
static inline int cpuidle_register_driver(struct cpuidle_driver *drv)
{return 0;}
static inline void cpuidle_unregister_driver(struct cpuidle_driver *drv) { }
static inline int cpuidle_register_device(struct cpuidle_device *dev)
{return 0;}
static inline void cpuidle_unregister_device(struct cpuidle_device *dev) { }
static inline void cpuidle_pause_and_lock(void) { }
static inline void cpuidle_resume_and_unlock(void) { }
static inline int cpuidle_enable_device(struct cpuidle_device *dev)
{return 0;}
static inline void cpuidle_disable_device(struct cpuidle_device *dev) { }
#endif
/******************************
* CPUIDLE GOVERNOR INTERFACE *
******************************/
struct cpuidle_governor {
char name[CPUIDLE_NAME_LEN];
struct list_head governor_list;
unsigned int rating;
int (*enable) (struct cpuidle_device *dev);
void (*disable) (struct cpuidle_device *dev);
int (*select) (struct cpuidle_device *dev);
void (*reflect) (struct cpuidle_device *dev);
struct module *owner;
};
#ifdef CONFIG_CPU_IDLE
extern int cpuidle_register_governor(struct cpuidle_governor *gov);
extern void cpuidle_unregister_governor(struct cpuidle_governor *gov);
#else
static inline int cpuidle_register_governor(struct cpuidle_governor *gov)
{return 0;}
static inline void cpuidle_unregister_governor(struct cpuidle_governor *gov) { }
#endif
#ifdef CONFIG_ARCH_HAS_CPU_RELAX
#define CPUIDLE_DRIVER_STATE_START 1
#else
#define CPUIDLE_DRIVER_STATE_START 0
#endif
#endif /* _LINUX_CPUIDLE_H */