diff options
Diffstat (limited to 'include/linux')
| -rw-r--r-- | include/linux/hrtimer.h | 130 | ||||
| -rw-r--r-- | include/linux/ktime.h | 15 |
2 files changed, 145 insertions, 0 deletions
diff --git a/include/linux/hrtimer.h b/include/linux/hrtimer.h new file mode 100644 index 00000000000..64f8d554fbb --- /dev/null +++ b/include/linux/hrtimer.h @@ -0,0 +1,130 @@ +/* + * include/linux/hrtimer.h + * + * hrtimers - High-resolution kernel timers + * + * Copyright(C) 2005, Thomas Gleixner <tglx@linutronix.de> + * Copyright(C) 2005, Red Hat, Inc., Ingo Molnar + * + * data type definitions, declarations, prototypes + * + * Started by: Thomas Gleixner and Ingo Molnar + * + * For licencing details see kernel-base/COPYING + */ +#ifndef _LINUX_HRTIMER_H +#define _LINUX_HRTIMER_H + +#include <linux/rbtree.h> +#include <linux/ktime.h> +#include <linux/init.h> +#include <linux/list.h> +#include <linux/wait.h> + +/* + * Mode arguments of xxx_hrtimer functions: + */ +enum hrtimer_mode { + HRTIMER_ABS, /* Time value is absolute */ + HRTIMER_REL, /* Time value is relative to now */ +}; + +enum hrtimer_restart { + HRTIMER_NORESTART, + HRTIMER_RESTART, +}; + +/* + * Timer states: + */ +enum hrtimer_state { + HRTIMER_INACTIVE, /* Timer is inactive */ + HRTIMER_EXPIRED, /* Timer is expired */ + HRTIMER_PENDING, /* Timer is pending */ +}; + +struct hrtimer_base; + +/** + * struct hrtimer - the basic hrtimer structure + * + * @node: red black tree node for time ordered insertion + * @list: list head for easier access to the time ordered list, + * without walking the red black tree. + * @expires: the absolute expiry time in the hrtimers internal + * representation. The time is related to the clock on + * which the timer is based. + * @state: state of the timer + * @function: timer expiry callback function + * @data: argument for the callback function + * @base: pointer to the timer base (per cpu and per clock) + * + * The hrtimer structure must be initialized by init_hrtimer_#CLOCKTYPE() + */ +struct hrtimer { + struct rb_node node; + struct list_head list; + ktime_t expires; + enum hrtimer_state state; + int (*function)(void *); + void *data; + struct hrtimer_base *base; +}; + +/** + * struct hrtimer_base - the timer base for a specific clock + * + * @index: clock type index for per_cpu support when moving a timer + * to a base on another cpu. + * @lock: lock protecting the base and associated timers + * @active: red black tree root node for the active timers + * @pending: list of pending timers for simple time ordered access + * @resolution: the resolution of the clock, in nanoseconds + * @get_time: function to retrieve the current time of the clock + * @curr_timer: the timer which is executing a callback right now + */ +struct hrtimer_base { + clockid_t index; + spinlock_t lock; + struct rb_root active; + struct list_head pending; + unsigned long resolution; + ktime_t (*get_time)(void); + struct hrtimer *curr_timer; +}; + +/* Exported timer functions: */ + +/* Initialize timers: */ +extern void hrtimer_init(struct hrtimer *timer, const clockid_t which_clock); +extern void hrtimer_rebase(struct hrtimer *timer, const clockid_t which_clock); + + +/* Basic timer operations: */ +extern int hrtimer_start(struct hrtimer *timer, ktime_t tim, + const enum hrtimer_mode mode); +extern int hrtimer_cancel(struct hrtimer *timer); +extern int hrtimer_try_to_cancel(struct hrtimer *timer); + +#define hrtimer_restart(timer) hrtimer_start((timer), (timer)->expires, HRTIMER_ABS) + +/* Query timers: */ +extern ktime_t hrtimer_get_remaining(const struct hrtimer *timer); +extern int hrtimer_get_res(const clockid_t which_clock, struct timespec *tp); + +static inline int hrtimer_active(const struct hrtimer *timer) +{ + return timer->state == HRTIMER_PENDING; +} + +/* Forward a hrtimer so it expires after now: */ +extern unsigned long hrtimer_forward(struct hrtimer *timer, + const ktime_t interval); + +/* Soft interrupt function to run the hrtimer queues: */ +extern void hrtimer_run_queues(void); + +/* Bootup initialization: */ +extern void __init hrtimers_init(void); + +#endif diff --git a/include/linux/ktime.h b/include/linux/ktime.h index 5b9a9eb82ba..222a047cc14 100644 --- a/include/linux/ktime.h +++ b/include/linux/ktime.h @@ -266,4 +266,19 @@ static inline u64 ktime_to_ns(const ktime_t kt) #endif +/* + * The resolution of the clocks. The resolution value is returned in + * the clock_getres() system call to give application programmers an + * idea of the (in)accuracy of timers. Timer values are rounded up to + * this resolution values. + */ +#define KTIME_REALTIME_RES (NSEC_PER_SEC/HZ) +#define KTIME_MONOTONIC_RES (NSEC_PER_SEC/HZ) + +/* Get the monotonic time in timespec format: */ +extern void ktime_get_ts(struct timespec *ts); + +/* Get the real (wall-) time in timespec format: */ +#define ktime_get_real_ts(ts) getnstimeofday(ts) + #endif |