[mirror_ubuntu-bionic-kernel.git] / include / linux / hrtimer.h

/*
 *  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>
#include <linux/percpu.h>
#include <linux/timer.h>
#include <linux/timerqueue.h>

struct hrtimer_clock_base;
struct hrtimer_cpu_base;

/*
 * Mode arguments of xxx_hrtimer functions:
 */
enum hrtimer_mode {
	HRTIMER_MODE_ABS = 0x0,		/* Time value is absolute */
	HRTIMER_MODE_REL = 0x1,		/* Time value is relative to now */
	HRTIMER_MODE_PINNED = 0x02,	/* Timer is bound to CPU */
	HRTIMER_MODE_ABS_PINNED = 0x02,
	HRTIMER_MODE_REL_PINNED = 0x03,
};

/*
 * Return values for the callback function
 */
enum hrtimer_restart {
	HRTIMER_NORESTART,	/* Timer is not restarted */
	HRTIMER_RESTART,	/* Timer must be restarted */
};

/*
 * Values to track state of the timer
 *
 * Possible states:
 *
 * 0x00		inactive
 * 0x01		enqueued into rbtree
 * 0x02		callback function running
 * 0x04		timer is migrated to another cpu
 *
 * Special cases:
 * 0x03		callback function running and enqueued
 *		(was requeued on another CPU)
 * 0x05		timer was migrated on CPU hotunplug
 *
 * The "callback function running and enqueued" status is only possible on
 * SMP. It happens for example when a posix timer expired and the callback
 * queued a signal. Between dropping the lock which protects the posix timer
 * and reacquiring the base lock of the hrtimer, another CPU can deliver the
 * signal and rearm the timer. We have to preserve the callback running state,
 * as otherwise the timer could be removed before the softirq code finishes the
 * the handling of the timer.
 *
 * The HRTIMER_STATE_ENQUEUED bit is always or'ed to the current state
 * to preserve the HRTIMER_STATE_CALLBACK in the above scenario. This
 * also affects HRTIMER_STATE_MIGRATE where the preservation is not
 * necessary. HRTIMER_STATE_MIGRATE is cleared after the timer is
 * enqueued on the new cpu.
 *
 * All state transitions are protected by cpu_base->lock.
 */
#define HRTIMER_STATE_INACTIVE	0x00
#define HRTIMER_STATE_ENQUEUED	0x01
#define HRTIMER_STATE_CALLBACK	0x02
#define HRTIMER_STATE_MIGRATE	0x04

/**
 * struct hrtimer - the basic hrtimer structure
 * @node:	timerqueue node, which also manages node.expires,
 *		the absolute expiry time in the hrtimers internal
 *		representation. The time is related to the clock on
 *		which the timer is based. Is setup by adding
 *		slack to the _softexpires value. For non range timers
 *		identical to _softexpires.
 * @_softexpires: the absolute earliest expiry time of the hrtimer.
 *		The time which was given as expiry time when the timer
 *		was armed.
 * @function:	timer expiry callback function
 * @base:	pointer to the timer base (per cpu and per clock)
 * @state:	state information (See bit values above)
 * @start_pid: timer statistics field to store the pid of the task which
 *		started the timer
 * @start_site:	timer statistics field to store the site where the timer
 *		was started
 * @start_comm: timer statistics field to store the name of the process which
 *		started the timer
 *
 * The hrtimer structure must be initialized by hrtimer_init()
 */
struct hrtimer {
	struct timerqueue_node		node;
	ktime_t				_softexpires;
	enum hrtimer_restart		(*function)(struct hrtimer *);
	struct hrtimer_clock_base	*base;
	unsigned long			state;
#ifdef CONFIG_TIMER_STATS
	int				start_pid;
	void				*start_site;
	char				start_comm[16];
#endif
};

/**
 * struct hrtimer_sleeper - simple sleeper structure
 * @timer:	embedded timer structure
 * @task:	task to wake up
 *
 * task is set to NULL, when the timer expires.
 */
struct hrtimer_sleeper {
	struct hrtimer timer;
	struct task_struct *task;
};

/**
 * struct hrtimer_clock_base - the timer base for a specific clock
 * @cpu_base:		per cpu clock base
 * @index:		clock type index for per_cpu support when moving a
 *			timer to a base on another cpu.
 * @clockid:		clock id for per_cpu support
 * @active:		red black tree root node for the active timers
 * @get_time:		function to retrieve the current time of the clock
 * @offset:		offset of this clock to the monotonic base
 */
struct hrtimer_clock_base {
	struct hrtimer_cpu_base	*cpu_base;
	int			index;
	clockid_t		clockid;
	struct timerqueue_head	active;
	ktime_t			(*get_time)(void);
	ktime_t			offset;
};

enum  hrtimer_base_type {
	HRTIMER_BASE_MONOTONIC,
	HRTIMER_BASE_REALTIME,
	HRTIMER_BASE_BOOTTIME,
	HRTIMER_BASE_TAI,
	HRTIMER_MAX_CLOCK_BASES,
};

/*
 * struct hrtimer_cpu_base - the per cpu clock bases
 * @lock:		lock protecting the base and associated clock bases
 *			and timers
 * @cpu:		cpu number
 * @active_bases:	Bitfield to mark bases with active timers
 * @clock_was_set_seq:	Sequence counter of clock was set events
 * @expires_next:	absolute time of the next event which was scheduled
 *			via clock_set_next_event()
 * @in_hrtirq:		hrtimer_interrupt() is currently executing
 * @hres_active:	State of high resolution mode
 * @hang_detected:	The last hrtimer interrupt detected a hang
 * @nr_events:		Total number of hrtimer interrupt events
 * @nr_retries:		Total number of hrtimer interrupt retries
 * @nr_hangs:		Total number of hrtimer interrupt hangs
 * @max_hang_time:	Maximum time spent in hrtimer_interrupt
 * @clock_base:		array of clock bases for this cpu
 */
struct hrtimer_cpu_base {
	raw_spinlock_t			lock;
	unsigned int			cpu;
	unsigned int			active_bases;
	unsigned int			clock_was_set_seq;
#ifdef CONFIG_HIGH_RES_TIMERS
	ktime_t				expires_next;
	int				in_hrtirq;
	int				hres_active;
	int				hang_detected;
	unsigned int			nr_events;
	unsigned int			nr_retries;
	unsigned int			nr_hangs;
	unsigned int			max_hang_time;
#endif
	struct hrtimer_clock_base	clock_base[HRTIMER_MAX_CLOCK_BASES];
};

static inline void hrtimer_set_expires(struct hrtimer *timer, ktime_t time)
{
	timer->node.expires = time;
	timer->_softexpires = time;
}

static inline void hrtimer_set_expires_range(struct hrtimer *timer, ktime_t time, ktime_t delta)
{
	timer->_softexpires = time;
	timer->node.expires = ktime_add_safe(time, delta);
}

static inline void hrtimer_set_expires_range_ns(struct hrtimer *timer, ktime_t time, unsigned long delta)
{
	timer->_softexpires = time;
	timer->node.expires = ktime_add_safe(time, ns_to_ktime(delta));
}

static inline void hrtimer_set_expires_tv64(struct hrtimer *timer, s64 tv64)
{
	timer->node.expires.tv64 = tv64;
	timer->_softexpires.tv64 = tv64;
}

static inline void hrtimer_add_expires(struct hrtimer *timer, ktime_t time)
{
	timer->node.expires = ktime_add_safe(timer->node.expires, time);
	timer->_softexpires = ktime_add_safe(timer->_softexpires, time);
}

static inline void hrtimer_add_expires_ns(struct hrtimer *timer, u64 ns)
{
	timer->node.expires = ktime_add_ns(timer->node.expires, ns);
	timer->_softexpires = ktime_add_ns(timer->_softexpires, ns);
}

static inline ktime_t hrtimer_get_expires(const struct hrtimer *timer)
{
	return timer->node.expires;
}

static inline ktime_t hrtimer_get_softexpires(const struct hrtimer *timer)
{
	return timer->_softexpires;
}

static inline s64 hrtimer_get_expires_tv64(const struct hrtimer *timer)
{
	return timer->node.expires.tv64;
}
static inline s64 hrtimer_get_softexpires_tv64(const struct hrtimer *timer)
{
	return timer->_softexpires.tv64;
}

static inline s64 hrtimer_get_expires_ns(const struct hrtimer *timer)
{
	return ktime_to_ns(timer->node.expires);
}

static inline ktime_t hrtimer_expires_remaining(const struct hrtimer *timer)
{
	return ktime_sub(timer->node.expires, timer->base->get_time());
}

static inline ktime_t hrtimer_cb_get_time(struct hrtimer *timer)
{
	return timer->base->get_time();
}

#ifdef CONFIG_HIGH_RES_TIMERS
struct clock_event_device;

extern void hrtimer_interrupt(struct clock_event_device *dev);

static inline int hrtimer_is_hres_active(struct hrtimer *timer)
{
	return timer->base->cpu_base->hres_active;
}

extern void hrtimer_peek_ahead_timers(void);

/*
 * 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 HIGH_RES_NSEC		1
# define KTIME_HIGH_RES		(ktime_t) { .tv64 = HIGH_RES_NSEC }
# define MONOTONIC_RES_NSEC	HIGH_RES_NSEC
# define KTIME_MONOTONIC_RES	KTIME_HIGH_RES

extern void clock_was_set_delayed(void);

extern unsigned int hrtimer_resolution;

#else

# define MONOTONIC_RES_NSEC	LOW_RES_NSEC
# define KTIME_MONOTONIC_RES	KTIME_LOW_RES

#define hrtimer_resolution	LOW_RES_NSEC

static inline void hrtimer_peek_ahead_timers(void) { }

static inline int hrtimer_is_hres_active(struct hrtimer *timer)
{
	return 0;
}

static inline void clock_was_set_delayed(void) { }

#endif

extern void clock_was_set(void);
#ifdef CONFIG_TIMERFD
extern void timerfd_clock_was_set(void);
#else
static inline void timerfd_clock_was_set(void) { }
#endif
extern void hrtimers_resume(void);

DECLARE_PER_CPU(struct tick_device, tick_cpu_device);


/* Exported timer functions: */

/* Initialize timers: */
extern void hrtimer_init(struct hrtimer *timer, clockid_t which_clock,
			 enum hrtimer_mode mode);

#ifdef CONFIG_DEBUG_OBJECTS_TIMERS
extern void hrtimer_init_on_stack(struct hrtimer *timer, clockid_t which_clock,
				  enum hrtimer_mode mode);

extern void destroy_hrtimer_on_stack(struct hrtimer *timer);
#else
static inline void hrtimer_init_on_stack(struct hrtimer *timer,
					 clockid_t which_clock,
					 enum hrtimer_mode mode)
{
	hrtimer_init(timer, which_clock, mode);
}
static inline void destroy_hrtimer_on_stack(struct hrtimer *timer) { }
#endif

/* Basic timer operations: */
extern int hrtimer_start(struct hrtimer *timer, ktime_t tim,
			 const enum hrtimer_mode mode);
extern int hrtimer_start_range_ns(struct hrtimer *timer, ktime_t tim,
			unsigned long range_ns, const enum hrtimer_mode mode);
extern int
__hrtimer_start_range_ns(struct hrtimer *timer, ktime_t tim,
			 unsigned long delta_ns,
			 const enum hrtimer_mode mode, int wakeup);

extern int hrtimer_cancel(struct hrtimer *timer);
extern int hrtimer_try_to_cancel(struct hrtimer *timer);

static inline int hrtimer_start_expires(struct hrtimer *timer,
						enum hrtimer_mode mode)
{
	unsigned long delta;
	ktime_t soft, hard;
	soft = hrtimer_get_softexpires(timer);
	hard = hrtimer_get_expires(timer);
	delta = ktime_to_ns(ktime_sub(hard, soft));
	return hrtimer_start_range_ns(timer, soft, delta, mode);
}

static inline int hrtimer_restart(struct hrtimer *timer)
{
	return hrtimer_start_expires(timer, HRTIMER_MODE_ABS);
}

/* Query timers: */
extern ktime_t hrtimer_get_remaining(const struct hrtimer *timer);

extern ktime_t hrtimer_get_next_event(void);

/*
 * A timer is active, when it is enqueued into the rbtree or the
 * callback function is running or it's in the state of being migrated
 * to another cpu.
 */
static inline int hrtimer_active(const struct hrtimer *timer)
{
	return timer->state != HRTIMER_STATE_INACTIVE;
}

/*
 * Helper function to check, whether the timer is on one of the queues
 */
static inline int hrtimer_is_queued(struct hrtimer *timer)
{
	return timer->state & HRTIMER_STATE_ENQUEUED;
}

/*
 * Helper function to check, whether the timer is running the callback
 * function
 */
static inline int hrtimer_callback_running(struct hrtimer *timer)
{
	return timer->state & HRTIMER_STATE_CALLBACK;
}

/* Forward a hrtimer so it expires after now: */
extern u64
hrtimer_forward(struct hrtimer *timer, ktime_t now, ktime_t interval);

/**
 * hrtimer_forward_now - forward the timer expiry so it expires after now
 * @timer:	hrtimer to forward
 * @interval:	the interval to forward
 *
 * Forward the timer expiry so it will expire after the current time
 * of the hrtimer clock base. Returns the number of overruns.
 *
 * Can be safely called from the callback function of @timer. If
 * called from other contexts @timer must neither be enqueued nor
 * running the callback and the caller needs to take care of
 * serialization.
 *
 * Note: This only updates the timer expiry value and does not requeue
 * the timer.
 */
static inline u64 hrtimer_forward_now(struct hrtimer *timer,
				      ktime_t interval)
{
	return hrtimer_forward(timer, timer->base->get_time(), interval);
}

/* Precise sleep: */
extern long hrtimer_nanosleep(struct timespec *rqtp,
			      struct timespec __user *rmtp,
			      const enum hrtimer_mode mode,
			      const clockid_t clockid);
extern long hrtimer_nanosleep_restart(struct restart_block *restart_block);

extern void hrtimer_init_sleeper(struct hrtimer_sleeper *sl,
				 struct task_struct *tsk);

extern int schedule_hrtimeout_range(ktime_t *expires, unsigned long delta,
						const enum hrtimer_mode mode);
extern int schedule_hrtimeout_range_clock(ktime_t *expires,
		unsigned long delta, const enum hrtimer_mode mode, int clock);
extern int schedule_hrtimeout(ktime_t *expires, const enum hrtimer_mode mode);

/* Soft interrupt function to run the hrtimer queues: */
extern void hrtimer_run_queues(void);
extern void hrtimer_run_pending(void);

/* Bootup initialization: */
extern void __init hrtimers_init(void);

/* Show pending timers: */
extern void sysrq_timer_list_show(void);

#endif
Commit	Line	Data
	1	/*
	2	* include/linux/hrtimer.h
	3	*
	4	* hrtimers - High-resolution kernel timers
	5	*
	6	* Copyright(C) 2005, Thomas Gleixner <tglx@linutronix.de>
	7	* Copyright(C) 2005, Red Hat, Inc., Ingo Molnar
	8	*
	9	* data type definitions, declarations, prototypes
	10	*
	11	* Started by: Thomas Gleixner and Ingo Molnar
	12	*
	13	* For licencing details see kernel-base/COPYING
	14	*/
	15	#ifndef _LINUX_HRTIMER_H
	16	#define _LINUX_HRTIMER_H
	17
	18	#include <linux/rbtree.h>
	19	#include <linux/ktime.h>
	20	#include <linux/init.h>
	21	#include <linux/list.h>
	22	#include <linux/wait.h>
	23	#include <linux/percpu.h>
	24	#include <linux/timer.h>
	25	#include <linux/timerqueue.h>
	26
	27	struct hrtimer_clock_base;
	28	struct hrtimer_cpu_base;
	29
	30	/*
	31	* Mode arguments of xxx_hrtimer functions:
	32	*/
	33	enum hrtimer_mode {
	34	HRTIMER_MODE_ABS = 0x0, /* Time value is absolute */
	35	HRTIMER_MODE_REL = 0x1, /* Time value is relative to now */
	36	HRTIMER_MODE_PINNED = 0x02, /* Timer is bound to CPU */
	37	HRTIMER_MODE_ABS_PINNED = 0x02,
	38	HRTIMER_MODE_REL_PINNED = 0x03,
	39	};
	40
	41	/*
	42	* Return values for the callback function
	43	*/
	44	enum hrtimer_restart {
	45	HRTIMER_NORESTART, /* Timer is not restarted */
	46	HRTIMER_RESTART, /* Timer must be restarted */
	47	};
	48
	49	/*
	50	* Values to track state of the timer
	51	*
	52	* Possible states:
	53	*
	54	* 0x00 inactive
	55	* 0x01 enqueued into rbtree
	56	* 0x02 callback function running
	57	* 0x04 timer is migrated to another cpu
	58	*
	59	* Special cases:
	60	* 0x03 callback function running and enqueued
	61	* (was requeued on another CPU)
	62	* 0x05 timer was migrated on CPU hotunplug
	63	*
	64	* The "callback function running and enqueued" status is only possible on
	65	* SMP. It happens for example when a posix timer expired and the callback
	66	* queued a signal. Between dropping the lock which protects the posix timer
	67	* and reacquiring the base lock of the hrtimer, another CPU can deliver the
	68	* signal and rearm the timer. We have to preserve the callback running state,
	69	* as otherwise the timer could be removed before the softirq code finishes the
	70	* the handling of the timer.
	71	*
	72	* The HRTIMER_STATE_ENQUEUED bit is always or'ed to the current state
	73	* to preserve the HRTIMER_STATE_CALLBACK in the above scenario. This
	74	* also affects HRTIMER_STATE_MIGRATE where the preservation is not
	75	* necessary. HRTIMER_STATE_MIGRATE is cleared after the timer is
	76	* enqueued on the new cpu.
	77	*
	78	* All state transitions are protected by cpu_base->lock.
	79	*/
	80	#define HRTIMER_STATE_INACTIVE 0x00
	81	#define HRTIMER_STATE_ENQUEUED 0x01
	82	#define HRTIMER_STATE_CALLBACK 0x02
	83	#define HRTIMER_STATE_MIGRATE 0x04
	84
	85	/**
	86	* struct hrtimer - the basic hrtimer structure
	87	* @node: timerqueue node, which also manages node.expires,
	88	* the absolute expiry time in the hrtimers internal
	89	* representation. The time is related to the clock on
	90	* which the timer is based. Is setup by adding
	91	* slack to the _softexpires value. For non range timers
	92	* identical to _softexpires.
	93	* @_softexpires: the absolute earliest expiry time of the hrtimer.
	94	* The time which was given as expiry time when the timer
	95	* was armed.
	96	* @function: timer expiry callback function
	97	* @base: pointer to the timer base (per cpu and per clock)
	98	* @state: state information (See bit values above)
	99	* @start_pid: timer statistics field to store the pid of the task which
	100	* started the timer
	101	* @start_site: timer statistics field to store the site where the timer
	102	* was started
	103	* @start_comm: timer statistics field to store the name of the process which
	104	* started the timer
	105	*
	106	* The hrtimer structure must be initialized by hrtimer_init()
	107	*/
	108	struct hrtimer {
	109	struct timerqueue_node node;
	110	ktime_t _softexpires;
	111	enum hrtimer_restart (function)(struct hrtimer );
	112	struct hrtimer_clock_base *base;
	113	unsigned long state;
	114	#ifdef CONFIG_TIMER_STATS
	115	int start_pid;
	116	void *start_site;
	117	char start_comm[16];
	118	#endif
	119	};
	120
	121	/**
	122	* struct hrtimer_sleeper - simple sleeper structure
	123	* @timer: embedded timer structure
	124	* @task: task to wake up
	125	*
	126	* task is set to NULL, when the timer expires.
	127	*/
	128	struct hrtimer_sleeper {
	129	struct hrtimer timer;
	130	struct task_struct *task;
	131	};
	132
	133	/**
	134	* struct hrtimer_clock_base - the timer base for a specific clock
	135	* @cpu_base: per cpu clock base
	136	* @index: clock type index for per_cpu support when moving a
	137	* timer to a base on another cpu.
	138	* @clockid: clock id for per_cpu support
	139	* @active: red black tree root node for the active timers
	140	* @get_time: function to retrieve the current time of the clock
	141	* @offset: offset of this clock to the monotonic base
	142	*/
	143	struct hrtimer_clock_base {
	144	struct hrtimer_cpu_base *cpu_base;
	145	int index;
	146	clockid_t clockid;
	147	struct timerqueue_head active;
	148	ktime_t (*get_time)(void);
	149	ktime_t offset;
	150	};
	151
	152	enum hrtimer_base_type {
	153	HRTIMER_BASE_MONOTONIC,
	154	HRTIMER_BASE_REALTIME,
	155	HRTIMER_BASE_BOOTTIME,
	156	HRTIMER_BASE_TAI,
	157	HRTIMER_MAX_CLOCK_BASES,
	158	};
	159
	160	/*
	161	* struct hrtimer_cpu_base - the per cpu clock bases
	162	* @lock: lock protecting the base and associated clock bases
	163	* and timers
	164	* @cpu: cpu number
	165	* @active_bases: Bitfield to mark bases with active timers
	166	* @clock_was_set_seq: Sequence counter of clock was set events
	167	* @expires_next: absolute time of the next event which was scheduled
	168	* via clock_set_next_event()
	169	* @in_hrtirq: hrtimer_interrupt() is currently executing
	170	* @hres_active: State of high resolution mode
	171	* @hang_detected: The last hrtimer interrupt detected a hang
	172	* @nr_events: Total number of hrtimer interrupt events
	173	* @nr_retries: Total number of hrtimer interrupt retries
	174	* @nr_hangs: Total number of hrtimer interrupt hangs
	175	* @max_hang_time: Maximum time spent in hrtimer_interrupt
	176	* @clock_base: array of clock bases for this cpu
	177	*/
	178	struct hrtimer_cpu_base {
	179	raw_spinlock_t lock;
	180	unsigned int cpu;
	181	unsigned int active_bases;
	182	unsigned int clock_was_set_seq;
	183	#ifdef CONFIG_HIGH_RES_TIMERS
	184	ktime_t expires_next;
	185	int in_hrtirq;
	186	int hres_active;
	187	int hang_detected;
	188	unsigned int nr_events;
	189	unsigned int nr_retries;
	190	unsigned int nr_hangs;
	191	unsigned int max_hang_time;
	192	#endif
	193	struct hrtimer_clock_base clock_base[HRTIMER_MAX_CLOCK_BASES];
	194	};
	195
	196	static inline void hrtimer_set_expires(struct hrtimer *timer, ktime_t time)
	197	{
	198	timer->node.expires = time;
	199	timer->_softexpires = time;
	200	}
	201
	202	static inline void hrtimer_set_expires_range(struct hrtimer *timer, ktime_t time, ktime_t delta)
	203	{
	204	timer->_softexpires = time;
	205	timer->node.expires = ktime_add_safe(time, delta);
	206	}
	207
	208	static inline void hrtimer_set_expires_range_ns(struct hrtimer *timer, ktime_t time, unsigned long delta)
	209	{
	210	timer->_softexpires = time;
	211	timer->node.expires = ktime_add_safe(time, ns_to_ktime(delta));
	212	}
	213
	214	static inline void hrtimer_set_expires_tv64(struct hrtimer *timer, s64 tv64)
	215	{
	216	timer->node.expires.tv64 = tv64;
	217	timer->_softexpires.tv64 = tv64;
	218	}
	219
	220	static inline void hrtimer_add_expires(struct hrtimer *timer, ktime_t time)
	221	{
	222	timer->node.expires = ktime_add_safe(timer->node.expires, time);
	223	timer->_softexpires = ktime_add_safe(timer->_softexpires, time);
	224	}
	225
	226	static inline void hrtimer_add_expires_ns(struct hrtimer *timer, u64 ns)
	227	{
	228	timer->node.expires = ktime_add_ns(timer->node.expires, ns);
	229	timer->_softexpires = ktime_add_ns(timer->_softexpires, ns);
	230	}
	231
	232	static inline ktime_t hrtimer_get_expires(const struct hrtimer *timer)
	233	{
	234	return timer->node.expires;
	235	}
	236
	237	static inline ktime_t hrtimer_get_softexpires(const struct hrtimer *timer)
	238	{
	239	return timer->_softexpires;
	240	}
	241
	242	static inline s64 hrtimer_get_expires_tv64(const struct hrtimer *timer)
	243	{
	244	return timer->node.expires.tv64;
	245	}
	246	static inline s64 hrtimer_get_softexpires_tv64(const struct hrtimer *timer)
	247	{
	248	return timer->_softexpires.tv64;
	249	}
	250
	251	static inline s64 hrtimer_get_expires_ns(const struct hrtimer *timer)
	252	{
	253	return ktime_to_ns(timer->node.expires);
	254	}
	255
	256	static inline ktime_t hrtimer_expires_remaining(const struct hrtimer *timer)
	257	{
	258	return ktime_sub(timer->node.expires, timer->base->get_time());
	259	}
	260
	261	static inline ktime_t hrtimer_cb_get_time(struct hrtimer *timer)
	262	{
	263	return timer->base->get_time();
	264	}
	265
	266	#ifdef CONFIG_HIGH_RES_TIMERS
	267	struct clock_event_device;
	268
	269	extern void hrtimer_interrupt(struct clock_event_device *dev);
	270
	271	static inline int hrtimer_is_hres_active(struct hrtimer *timer)
	272	{
	273	return timer->base->cpu_base->hres_active;
	274	}
	275
	276	extern void hrtimer_peek_ahead_timers(void);
	277
	278	/*
	279	* The resolution of the clocks. The resolution value is returned in
	280	* the clock_getres() system call to give application programmers an
	281	* idea of the (in)accuracy of timers. Timer values are rounded up to
	282	* this resolution values.
	283	*/
	284	# define HIGH_RES_NSEC 1
	285	# define KTIME_HIGH_RES (ktime_t) { .tv64 = HIGH_RES_NSEC }
	286	# define MONOTONIC_RES_NSEC HIGH_RES_NSEC
	287	# define KTIME_MONOTONIC_RES KTIME_HIGH_RES
	288
	289	extern void clock_was_set_delayed(void);
	290
	291	extern unsigned int hrtimer_resolution;
	292
	293	#else
	294
	295	# define MONOTONIC_RES_NSEC LOW_RES_NSEC
	296	# define KTIME_MONOTONIC_RES KTIME_LOW_RES
	297
	298	#define hrtimer_resolution LOW_RES_NSEC
	299
	300	static inline void hrtimer_peek_ahead_timers(void) { }
	301
	302	static inline int hrtimer_is_hres_active(struct hrtimer *timer)
	303	{
	304	return 0;
	305	}
	306
	307	static inline void clock_was_set_delayed(void) { }
	308
	309	#endif
	310
	311	extern void clock_was_set(void);
	312	#ifdef CONFIG_TIMERFD
	313	extern void timerfd_clock_was_set(void);
	314	#else
	315	static inline void timerfd_clock_was_set(void) { }
	316	#endif
	317	extern void hrtimers_resume(void);
	318
	319	DECLARE_PER_CPU(struct tick_device, tick_cpu_device);
	320
	321
	322	/* Exported timer functions: */
	323
	324	/* Initialize timers: */
	325	extern void hrtimer_init(struct hrtimer *timer, clockid_t which_clock,
	326	enum hrtimer_mode mode);
	327
	328	#ifdef CONFIG_DEBUG_OBJECTS_TIMERS
	329	extern void hrtimer_init_on_stack(struct hrtimer *timer, clockid_t which_clock,
	330	enum hrtimer_mode mode);
	331
	332	extern void destroy_hrtimer_on_stack(struct hrtimer *timer);
	333	#else
	334	static inline void hrtimer_init_on_stack(struct hrtimer *timer,
	335	clockid_t which_clock,
	336	enum hrtimer_mode mode)
	337	{
	338	hrtimer_init(timer, which_clock, mode);
	339	}
	340	static inline void destroy_hrtimer_on_stack(struct hrtimer *timer) { }
	341	#endif
	342
	343	/* Basic timer operations: */
	344	extern int hrtimer_start(struct hrtimer *timer, ktime_t tim,
	345	const enum hrtimer_mode mode);
	346	extern int hrtimer_start_range_ns(struct hrtimer *timer, ktime_t tim,
	347	unsigned long range_ns, const enum hrtimer_mode mode);
	348	extern int
	349	__hrtimer_start_range_ns(struct hrtimer *timer, ktime_t tim,
	350	unsigned long delta_ns,
	351	const enum hrtimer_mode mode, int wakeup);
	352
	353	extern int hrtimer_cancel(struct hrtimer *timer);
	354	extern int hrtimer_try_to_cancel(struct hrtimer *timer);
	355
	356	static inline int hrtimer_start_expires(struct hrtimer *timer,
	357	enum hrtimer_mode mode)
	358	{
	359	unsigned long delta;
	360	ktime_t soft, hard;
	361	soft = hrtimer_get_softexpires(timer);
	362	hard = hrtimer_get_expires(timer);
	363	delta = ktime_to_ns(ktime_sub(hard, soft));
	364	return hrtimer_start_range_ns(timer, soft, delta, mode);
	365	}
	366
	367	static inline int hrtimer_restart(struct hrtimer *timer)
	368	{
	369	return hrtimer_start_expires(timer, HRTIMER_MODE_ABS);
	370	}
	371
	372	/* Query timers: */
	373	extern ktime_t hrtimer_get_remaining(const struct hrtimer *timer);
	374
	375	extern ktime_t hrtimer_get_next_event(void);
	376
	377	/*
	378	* A timer is active, when it is enqueued into the rbtree or the
	379	* callback function is running or it's in the state of being migrated
	380	* to another cpu.
	381	*/
	382	static inline int hrtimer_active(const struct hrtimer *timer)
	383	{
	384	return timer->state != HRTIMER_STATE_INACTIVE;
	385	}
	386
	387	/*
	388	* Helper function to check, whether the timer is on one of the queues
	389	*/
	390	static inline int hrtimer_is_queued(struct hrtimer *timer)
	391	{
	392	return timer->state & HRTIMER_STATE_ENQUEUED;
	393	}
	394
	395	/*
	396	* Helper function to check, whether the timer is running the callback
	397	* function
	398	*/
	399	static inline int hrtimer_callback_running(struct hrtimer *timer)
	400	{
	401	return timer->state & HRTIMER_STATE_CALLBACK;
	402	}
	403
	404	/* Forward a hrtimer so it expires after now: */
	405	extern u64
	406	hrtimer_forward(struct hrtimer *timer, ktime_t now, ktime_t interval);
	407
	408	/**
	409	* hrtimer_forward_now - forward the timer expiry so it expires after now
	410	* @timer: hrtimer to forward
	411	* @interval: the interval to forward
	412	*
	413	* Forward the timer expiry so it will expire after the current time
	414	* of the hrtimer clock base. Returns the number of overruns.
	415	*
	416	* Can be safely called from the callback function of @timer. If
	417	* called from other contexts @timer must neither be enqueued nor
	418	* running the callback and the caller needs to take care of
	419	* serialization.
	420	*
	421	* Note: This only updates the timer expiry value and does not requeue
	422	* the timer.
	423	*/
	424	static inline u64 hrtimer_forward_now(struct hrtimer *timer,
	425	ktime_t interval)
	426	{
	427	return hrtimer_forward(timer, timer->base->get_time(), interval);
	428	}
	429
	430	/* Precise sleep: */
	431	extern long hrtimer_nanosleep(struct timespec *rqtp,
	432	struct timespec __user *rmtp,
	433	const enum hrtimer_mode mode,
	434	const clockid_t clockid);
	435	extern long hrtimer_nanosleep_restart(struct restart_block *restart_block);
	436
	437	extern void hrtimer_init_sleeper(struct hrtimer_sleeper *sl,
	438	struct task_struct *tsk);
	439
	440	extern int schedule_hrtimeout_range(ktime_t *expires, unsigned long delta,
	441	const enum hrtimer_mode mode);
	442	extern int schedule_hrtimeout_range_clock(ktime_t *expires,
	443	unsigned long delta, const enum hrtimer_mode mode, int clock);
	444	extern int schedule_hrtimeout(ktime_t *expires, const enum hrtimer_mode mode);
	445
	446	/* Soft interrupt function to run the hrtimer queues: */
	447	extern void hrtimer_run_queues(void);
	448	extern void hrtimer_run_pending(void);
	449
	450	/* Bootup initialization: */
	451	extern void __init hrtimers_init(void);
	452
	453	/* Show pending timers: */
	454	extern void sysrq_timer_list_show(void);
	455
	456	#endif