Initial import

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diff --git a/include/linux/hrtimer.h b/include/linux/hrtimer.h
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--- /dev/null
+++ b/include/linux/hrtimer.h
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+/*
+ *  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
+ * @resolution:		the resolution of the clock, in nanoseconds
+ * @get_time:		function to retrieve the current time of the clock
+ * @softirq_time:	the time when running the hrtimer queue in the softirq
+ * @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			resolution;
+	ktime_t			(*get_time)(void);
+	ktime_t			softirq_time;
+	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:	Indicates that clock was set from irq context.
+ * @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;
+#ifdef CONFIG_HIGH_RES_TIMERS
+	ktime_t				expires_next;
+	int				in_hrtirq;
+	int				hres_active;
+	int				hang_detected;
+	unsigned long			nr_events;
+	unsigned long			nr_retries;
+	unsigned long			nr_hangs;
+	ktime_t				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());
+}
+
+#ifdef CONFIG_HIGH_RES_TIMERS
+struct clock_event_device;
+
+extern void hrtimer_interrupt(struct clock_event_device *dev);
+
+/*
+ * In high resolution mode the time reference must be read accurate
+ */
+static inline ktime_t hrtimer_cb_get_time(struct hrtimer *timer)
+{
+	return timer->base->get_time();
+}
+
+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);
+
+#else
+
+# define MONOTONIC_RES_NSEC	LOW_RES_NSEC
+# define KTIME_MONOTONIC_RES	KTIME_LOW_RES
+
+static inline void hrtimer_peek_ahead_timers(void) { }
+
+/*
+ * In non high resolution mode the time reference is taken from
+ * the base softirq time variable.
+ */
+static inline ktime_t hrtimer_cb_get_time(struct hrtimer *timer)
+{
+	return timer->base->softirq_time;
+}
+
+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 int hrtimer_get_res(const clockid_t which_clock, struct timespec *tp);
+
+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);
+
+/* Forward a hrtimer so it expires after the hrtimer's current now */
+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