9  *  In contrast to the low-resolution timeout API, aka timer wheel,
16  *	Based on the original timer wheel code
42 #include <linux/timer.h>
48 #include <trace/events/timer.h>
64  * The timer bases:
67  * into the timer bases by the hrtimer_base_type enum. When trying
147  * timer->base->cpu_base
161  * means that all timers which are tied to this base via timer->base are
167  * When the timer's base is locked, and the timer removed from list, it is
168  * possible to set timer->base = &migration_base and drop the lock: the timer
172 struct hrtimer_clock_base *lock_hrtimer_base(const struct hrtimer *timer,  in lock_hrtimer_base()  argument
174 	__acquires(&timer->base->lock)  in lock_hrtimer_base()
179 		base = READ_ONCE(timer->base);  in lock_hrtimer_base()
182 			if (likely(base == timer->base))  in lock_hrtimer_base()
184 			/* The timer has migrated to another CPU: */  in lock_hrtimer_base()
195  * If the elected target is remote and its next event is after the timer
205 static bool hrtimer_suitable_target(struct hrtimer *timer, struct hrtimer_clock_base *new_base,  in hrtimer_suitable_target()  argument
220 	 * next remote target event is after this timer. Keep the  in hrtimer_suitable_target()
227 	expires = ktime_sub(hrtimer_get_expires(timer), new_base->offset);  in hrtimer_suitable_target()
248  * We switch the timer base to a power-optimized selected CPU target,
251  *	- timer migration is enabled
252  *	- the timer callback is not running
253  *	- the timer is not the first expiring timer on the new target
255  * If one of the above requirements is not fulfilled we move the timer
257  * the timer callback is currently running.
260 switch_hrtimer_base(struct hrtimer *timer, struct hrtimer_clock_base *base,  in switch_hrtimer_base()  argument
274 		 * We are trying to move timer to new_base.  in switch_hrtimer_base()
275 		 * However we can't change timer's base while it is running,  in switch_hrtimer_base()
278 		 * code will take care of this when the timer function has  in switch_hrtimer_base()
280 		 * the timer is enqueued.  in switch_hrtimer_base()
282 		if (unlikely(hrtimer_callback_running(timer)))  in switch_hrtimer_base()
286 		WRITE_ONCE(timer->base, &migration_base);  in switch_hrtimer_base()
290 		if (!hrtimer_suitable_target(timer, new_base, new_cpu_base,  in switch_hrtimer_base()
295 			WRITE_ONCE(timer->base, base);  in switch_hrtimer_base()
298 		WRITE_ONCE(timer->base, new_base);  in switch_hrtimer_base()
300 		if (!hrtimer_suitable_target(timer, new_base,  new_cpu_base, this_cpu_base)) {  in switch_hrtimer_base()
311 lock_hrtimer_base(const struct hrtimer *timer, unsigned long *flags)  in lock_hrtimer_base()  argument
312 	__acquires(&timer->base->cpu_base->lock)  in lock_hrtimer_base()
314 	struct hrtimer_clock_base *base = timer->base;  in lock_hrtimer_base()
388 	struct hrtimer *timer = addr;  in hrtimer_fixup_init()  local
392 		hrtimer_cancel(timer);  in hrtimer_fixup_init()
393 		debug_object_init(timer, &hrtimer_debug_descr);  in hrtimer_fixup_init()
422 	struct hrtimer *timer = addr;  in hrtimer_fixup_free()  local
426 		hrtimer_cancel(timer);  in hrtimer_fixup_free()
427 		debug_object_free(timer, &hrtimer_debug_descr);  in hrtimer_fixup_free()
442 static inline void debug_hrtimer_init(struct hrtimer *timer)  in debug_hrtimer_init()  argument
444 	debug_object_init(timer, &hrtimer_debug_descr);  in debug_hrtimer_init()
447 static inline void debug_hrtimer_init_on_stack(struct hrtimer *timer)  in debug_hrtimer_init_on_stack()  argument
449 	debug_object_init_on_stack(timer, &hrtimer_debug_descr);  in debug_hrtimer_init_on_stack()
452 static inline void debug_hrtimer_activate(struct hrtimer *timer,  in debug_hrtimer_activate()  argument
455 	debug_object_activate(timer, &hrtimer_debug_descr);  in debug_hrtimer_activate()
458 static inline void debug_hrtimer_deactivate(struct hrtimer *timer)  in debug_hrtimer_deactivate()  argument
460 	debug_object_deactivate(timer, &hrtimer_debug_descr);  in debug_hrtimer_deactivate()
463 void destroy_hrtimer_on_stack(struct hrtimer *timer)  in destroy_hrtimer_on_stack()  argument
465 	debug_object_free(timer, &hrtimer_debug_descr);  in destroy_hrtimer_on_stack()
471 static inline void debug_hrtimer_init(struct hrtimer *timer) { }  in debug_hrtimer_init()  argument
472 static inline void debug_hrtimer_init_on_stack(struct hrtimer *timer) { }  in debug_hrtimer_init_on_stack()  argument
473 static inline void debug_hrtimer_activate(struct hrtimer *timer,  in debug_hrtimer_activate()  argument
475 static inline void debug_hrtimer_deactivate(struct hrtimer *timer) { }  in debug_hrtimer_deactivate()  argument
479 debug_init(struct hrtimer *timer, clockid_t clockid,  in debug_init()  argument
482 	debug_hrtimer_init(timer);  in debug_init()
483 	trace_hrtimer_init(timer, clockid, mode);  in debug_init()
486 static inline void debug_init_on_stack(struct hrtimer *timer, clockid_t clockid,  in debug_init_on_stack()  argument
489 	debug_hrtimer_init_on_stack(timer);  in debug_init_on_stack()
490 	trace_hrtimer_init(timer, clockid, mode);  in debug_init_on_stack()
493 static inline void debug_activate(struct hrtimer *timer,  in debug_activate()  argument
496 	debug_hrtimer_activate(timer, mode);  in debug_activate()
497 	trace_hrtimer_start(timer, mode);  in debug_activate()
500 static inline void debug_deactivate(struct hrtimer *timer)  in debug_deactivate()  argument
502 	debug_hrtimer_deactivate(timer);  in debug_deactivate()
503 	trace_hrtimer_cancel(timer);  in debug_deactivate()
533 		struct hrtimer *timer;  in __hrtimer_next_event_base()  local
536 		timer = container_of(next, struct hrtimer, node);  in __hrtimer_next_event_base()
537 		if (timer == exclude) {  in __hrtimer_next_event_base()
538 			/* Get to the next timer in the queue. */  in __hrtimer_next_event_base()
543 			timer = container_of(next, struct hrtimer, node);  in __hrtimer_next_event_base()
545 		expires = ktime_sub(hrtimer_get_expires(timer), base->offset);  in __hrtimer_next_event_base()
549 			/* Skip cpu_base update if a timer is being excluded. */  in __hrtimer_next_event_base()
553 			if (timer->is_soft)  in __hrtimer_next_event_base()
554 				cpu_base->softirq_next_timer = timer;  in __hrtimer_next_event_base()
556 				cpu_base->next_timer = timer;  in __hrtimer_next_event_base()
635 	 * If a softirq timer is expiring first, update cpu_base->next_timer  in hrtimer_update_next_event()
681 	 * If a hang was detected in the last timer interrupt then we  in __hrtimer_reprogram()
718 /* High resolution timer related functions */
722  * High resolution timer enabled ?
794 	 * If high resolution mode is active then the next expiring timer  in retrigger_next_event()
799 	 * of the next expiring timer is enough. The return from the SMP  in retrigger_next_event()
816  * When a timer is enqueued and expires earlier than the already enqueued
817  * timers, we have to check, whether it expires earlier than the timer for
822 static void hrtimer_reprogram(struct hrtimer *timer, bool reprogram)  in hrtimer_reprogram()  argument
825 	struct hrtimer_clock_base *base = timer->base;  in hrtimer_reprogram()
826 	ktime_t expires = ktime_sub(hrtimer_get_expires(timer), base->offset);  in hrtimer_reprogram()
828 	WARN_ON_ONCE(hrtimer_get_expires_tv64(timer) < 0);  in hrtimer_reprogram()
831 	 * CLOCK_REALTIME timer might be requested with an absolute  in hrtimer_reprogram()
837 	if (timer->is_soft) {  in hrtimer_reprogram()
853 		timer_cpu_base->softirq_next_timer = timer;  in hrtimer_reprogram()
862 	 * If the timer is not on the current cpu, we cannot reprogram  in hrtimer_reprogram()
878 	cpu_base->next_timer = timer;  in hrtimer_reprogram()
880 	__hrtimer_reprogram(cpu_base, timer, expires);  in hrtimer_reprogram()
898 	 * the next expiring timer.  in update_needs_ipi()
912 	 * will reevaluate the first expiring timer of all clock bases  in update_needs_ipi()
920 	 * timer in a clock base is moving ahead of the first expiring timer of  in update_needs_ipi()
952  * when the change moves an affected timer ahead of the first expiring
953  * timer on that CPU. Obviously remote per CPU clock event devices cannot
1029 void unlock_hrtimer_base(const struct hrtimer *timer, unsigned long *flags)  in unlock_hrtimer_base()  argument
1030 	__releases(&timer->base->cpu_base->lock)  in unlock_hrtimer_base()
1032 	raw_spin_unlock_irqrestore(&timer->base->cpu_base->lock, *flags);  in unlock_hrtimer_base()
1036  * hrtimer_forward() - forward the timer expiry
1037  * @timer:	hrtimer to forward
1041  * Forward the timer expiry so it will expire in the future.
1044  *  This only updates the timer expiry value and does not requeue the timer.
1048  * Context: Can be safely called from the callback function of @timer. If called
1049  *          from other contexts @timer must neither be enqueued nor running the
1054 u64 hrtimer_forward(struct hrtimer *timer, ktime_t now, ktime_t interval)  in hrtimer_forward()  argument
1059 	delta = ktime_sub(now, hrtimer_get_expires(timer));  in hrtimer_forward()
1064 	if (WARN_ON(timer->state & HRTIMER_STATE_ENQUEUED))  in hrtimer_forward()
1074 		hrtimer_add_expires_ns(timer, incr * orun);  in hrtimer_forward()
1075 		if (hrtimer_get_expires_tv64(timer) > now)  in hrtimer_forward()
1083 	hrtimer_add_expires(timer, interval);  in hrtimer_forward()
1090  * enqueue_hrtimer - internal function to (re)start a timer
1092  * The timer is inserted in expiry order. Insertion into the
1095  * Returns true when the new timer is the leftmost timer in the tree.
1097 static bool enqueue_hrtimer(struct hrtimer *timer, struct hrtimer_clock_base *base,  in enqueue_hrtimer()  argument
1100 	debug_activate(timer, mode);  in enqueue_hrtimer()
1106 	WRITE_ONCE(timer->state, HRTIMER_STATE_ENQUEUED);  in enqueue_hrtimer()
1108 	return timerqueue_add(&base->active, &timer->node);  in enqueue_hrtimer()
1112  * __remove_hrtimer - internal function to remove a timer
1116  * High resolution timer mode reprograms the clock event device when the
1117  * timer is the one which expires next. The caller can disable this by setting
1119  * anyway (e.g. timer interrupt)
1121 static void __remove_hrtimer(struct hrtimer *timer,  in __remove_hrtimer()  argument
1126 	u8 state = timer->state;  in __remove_hrtimer()
1129 	WRITE_ONCE(timer->state, newstate);  in __remove_hrtimer()
1133 	if (!timerqueue_del(&base->active, &timer->node))  in __remove_hrtimer()
1139 	 * timer on a remote cpu. No harm as we never dereference  in __remove_hrtimer()
1142 	 * remote cpu later on if the same timer gets enqueued again.  in __remove_hrtimer()
1144 	if (reprogram && timer == cpu_base->next_timer)  in __remove_hrtimer()
1152 remove_hrtimer(struct hrtimer *timer, struct hrtimer_clock_base *base,  in remove_hrtimer()  argument
1155 	u8 state = timer->state;  in remove_hrtimer()
1161 		 * Remove the timer and force reprogramming when high  in remove_hrtimer()
1162 		 * resolution mode is active and the timer is on the current  in remove_hrtimer()
1163 		 * CPU. If we remove a timer on another CPU, reprogramming is  in remove_hrtimer()
1168 		debug_deactivate(timer);  in remove_hrtimer()
1172 		 * If the timer is not restarted then reprogramming is  in remove_hrtimer()
1173 		 * required if the timer is local. If it is local and about  in remove_hrtimer()
1182 		__remove_hrtimer(timer, base, state, reprogram);  in remove_hrtimer()
1188 static inline ktime_t hrtimer_update_lowres(struct hrtimer *timer, ktime_t tim,  in hrtimer_update_lowres()  argument
1197 	timer->is_rel = mode & HRTIMER_MODE_REL;  in hrtimer_update_lowres()
1198 	if (timer->is_rel)  in hrtimer_update_lowres()
1229 static int __hrtimer_start_range_ns(struct hrtimer *timer, ktime_t tim,  in __hrtimer_start_range_ns()  argument
1238 	 * If the timer is on the local cpu base and is the first expiring  in __hrtimer_start_range_ns()
1239 	 * timer then this might end up reprogramming the hardware twice  in __hrtimer_start_range_ns()
1241 	 * reprogram on removal, keep the timer local to the current CPU  in __hrtimer_start_range_ns()
1243 	 * it is the new first expiring timer again or not.  in __hrtimer_start_range_ns()
1246 	force_local &= base->cpu_base->next_timer == timer;  in __hrtimer_start_range_ns()
1255 	 * Remove an active timer from the queue. In case it is not queued  in __hrtimer_start_range_ns()
1259 	 * If it's on the current CPU and the first expiring timer, then  in __hrtimer_start_range_ns()
1260 	 * skip reprogramming, keep the timer local and enforce  in __hrtimer_start_range_ns()
1261 	 * reprogramming later if it was the first expiring timer.  This  in __hrtimer_start_range_ns()
1265 	remove_hrtimer(timer, base, true, force_local);  in __hrtimer_start_range_ns()
1270 	tim = hrtimer_update_lowres(timer, tim, mode);  in __hrtimer_start_range_ns()
1272 	hrtimer_set_expires_range_ns(timer, tim, delta_ns);  in __hrtimer_start_range_ns()
1274 	/* Switch the timer base, if necessary: */  in __hrtimer_start_range_ns()
1276 		new_base = switch_hrtimer_base(timer, base,  in __hrtimer_start_range_ns()
1282 	first = enqueue_hrtimer(timer, new_base, mode);  in __hrtimer_start_range_ns()
1285 		 * If the current CPU base is online, then the timer is  in __hrtimer_start_range_ns()
1287 		 * expiring timer there.  in __hrtimer_start_range_ns()
1293 		 * Timer was enqueued remote because the current base is  in __hrtimer_start_range_ns()
1294 		 * already offline. If the timer is the first to expire,  in __hrtimer_start_range_ns()
1306 	 * Timer was forced to stay on the current CPU to avoid  in __hrtimer_start_range_ns()
1308 	 * hardware by evaluating the new first expiring timer.  in __hrtimer_start_range_ns()
1316  * @timer:	the timer to be added
1318  * @delta_ns:	"slack" range for the timer
1319  * @mode:	timer mode: absolute (HRTIMER_MODE_ABS) or
1323 void hrtimer_start_range_ns(struct hrtimer *timer, ktime_t tim,  in hrtimer_start_range_ns()  argument
1329 	if (WARN_ON_ONCE(!timer->function))  in hrtimer_start_range_ns()
1337 		WARN_ON_ONCE(!(mode & HRTIMER_MODE_SOFT) ^ !timer->is_soft);  in hrtimer_start_range_ns()
1339 		WARN_ON_ONCE(!(mode & HRTIMER_MODE_HARD) ^ !timer->is_hard);  in hrtimer_start_range_ns()
1341 	base = lock_hrtimer_base(timer, &flags);  in hrtimer_start_range_ns()
1343 	if (__hrtimer_start_range_ns(timer, tim, delta_ns, mode, base))  in hrtimer_start_range_ns()
1344 		hrtimer_reprogram(timer, true);  in hrtimer_start_range_ns()
1346 	unlock_hrtimer_base(timer, &flags);  in hrtimer_start_range_ns()
1351  * hrtimer_try_to_cancel - try to deactivate a timer
1352  * @timer:	hrtimer to stop
1356  *  *  0 when the timer was not active
1357  *  *  1 when the timer was active
1358  *  * -1 when the timer is currently executing the callback function and
1361 int hrtimer_try_to_cancel(struct hrtimer *timer)  in hrtimer_try_to_cancel()  argument
1368 	 * Check lockless first. If the timer is not active (neither  in hrtimer_try_to_cancel()
1373 	if (!hrtimer_active(timer))  in hrtimer_try_to_cancel()
1376 	base = lock_hrtimer_base(timer, &flags);  in hrtimer_try_to_cancel()
1378 	if (!hrtimer_callback_running(timer))  in hrtimer_try_to_cancel()
1379 		ret = remove_hrtimer(timer, base, false, false);  in hrtimer_try_to_cancel()
1381 	unlock_hrtimer_base(timer, &flags);  in hrtimer_try_to_cancel()
1410  * the timer callback to finish. Drop expiry_lock and reacquire it. That
1438  * deletion of a timer failed because the timer callback function was
1442  * in the middle of a timer callback, then calling del_timer_sync() can
1445  *  - If the caller is on a remote CPU then it has to spin wait for the timer
1448  *  - If the caller originates from the task which preempted the timer
1449  *    handler on the same CPU, then spin waiting for the timer handler to
1452 void hrtimer_cancel_wait_running(const struct hrtimer *timer)  in hrtimer_cancel_wait_running()  argument
1455 	struct hrtimer_clock_base *base = READ_ONCE(timer->base);  in hrtimer_cancel_wait_running()
1458 	 * Just relax if the timer expires in hard interrupt context or if  in hrtimer_cancel_wait_running()
1461 	if (!timer->is_soft || is_migration_base(base)) {  in hrtimer_cancel_wait_running()
1468 	 * held by the softirq across the timer callback. Drop the lock  in hrtimer_cancel_wait_running()
1469 	 * immediately so the softirq can expire the next timer. In theory  in hrtimer_cancel_wait_running()
1470 	 * the timer could already be running again, but that's more than  in hrtimer_cancel_wait_running()
1490  * hrtimer_cancel - cancel a timer and wait for the handler to finish.
1491  * @timer:	the timer to be cancelled
1494  *  0 when the timer was not active
1495  *  1 when the timer was active
1497 int hrtimer_cancel(struct hrtimer *timer)  in hrtimer_cancel()  argument
1502 		ret = hrtimer_try_to_cancel(timer);  in hrtimer_cancel()
1505 			hrtimer_cancel_wait_running(timer);  in hrtimer_cancel()
1512  * __hrtimer_get_remaining - get remaining time for the timer
1513  * @timer:	the timer to read
1516 ktime_t __hrtimer_get_remaining(const struct hrtimer *timer, bool adjust)  in __hrtimer_get_remaining()  argument
1521 	lock_hrtimer_base(timer, &flags);  in __hrtimer_get_remaining()
1523 		rem = hrtimer_expires_remaining_adjusted(timer);  in __hrtimer_get_remaining()
1525 		rem = hrtimer_expires_remaining(timer);  in __hrtimer_get_remaining()
1526 	unlock_hrtimer_base(timer, &flags);  in __hrtimer_get_remaining()
1536  * Returns the next expiry time or KTIME_MAX if no timer is pending.
1555  * hrtimer_next_event_without - time until next expiry event w/o one timer
1556  * @exclude:	timer to exclude
1605 static void __hrtimer_init(struct hrtimer *timer, clockid_t clock_id,  in __hrtimer_init()  argument
1621 	memset(timer, 0, sizeof(struct hrtimer));  in __hrtimer_init()
1635 	timer->is_soft = softtimer;  in __hrtimer_init()
1636 	timer->is_hard = !!(mode & HRTIMER_MODE_HARD);  in __hrtimer_init()
1637 	timer->base = &cpu_base->clock_base[base];  in __hrtimer_init()
1638 	timerqueue_init(&timer->node);  in __hrtimer_init()
1641 static void __hrtimer_setup(struct hrtimer *timer,  in __hrtimer_setup()  argument
1645 	__hrtimer_init(timer, clock_id, mode);  in __hrtimer_setup()
1648 		timer->function = hrtimer_dummy_timeout;  in __hrtimer_setup()
1650 		timer->function = function;  in __hrtimer_setup()
1654  * hrtimer_init - initialize a timer to the given clock
1655  * @timer:	the timer to be initialized
1665 void hrtimer_init(struct hrtimer *timer, clockid_t clock_id,  in hrtimer_init()  argument
1668 	debug_init(timer, clock_id, mode);  in hrtimer_init()
1669 	__hrtimer_init(timer, clock_id, mode);  in hrtimer_init()
1674  * hrtimer_setup - initialize a timer to the given clock
1675  * @timer:	the timer to be initialized
1686 void hrtimer_setup(struct hrtimer *timer, enum hrtimer_restart (*function)(struct hrtimer *),  in hrtimer_setup()  argument
1689 	debug_init(timer, clock_id, mode);  in hrtimer_setup()
1690 	__hrtimer_setup(timer, function, clock_id, mode);  in hrtimer_setup()
1695  * hrtimer_setup_on_stack - initialize a timer on stack memory
1696  * @timer:	The timer to be initialized
1699  * @mode:       The timer mode
1704 void hrtimer_setup_on_stack(struct hrtimer *timer,  in hrtimer_setup_on_stack()  argument
1708 	debug_init_on_stack(timer, clock_id, mode);  in hrtimer_setup_on_stack()
1709 	__hrtimer_setup(timer, function, clock_id, mode);  in hrtimer_setup_on_stack()
1714  * A timer is active, when it is enqueued into the rbtree or the
1720 bool hrtimer_active(const struct hrtimer *timer)  in hrtimer_active()  argument
1726 		base = READ_ONCE(timer->base);  in hrtimer_active()
1729 		if (timer->state != HRTIMER_STATE_INACTIVE ||  in hrtimer_active()
1730 		    base->running == timer)  in hrtimer_active()
1734 		 base != READ_ONCE(timer->base));  in hrtimer_active()
1744  *  - queued:	the timer is queued
1745  *  - callback:	the timer is being ran
1746  *  - post:	the timer is inactive or (re)queued
1748  * On the read side we ensure we observe timer->state and cpu_base->running
1750  * This includes timer->base changing because sequence numbers alone are
1760 			  struct hrtimer *timer, ktime_t *now,  in __run_hrtimer()  argument
1769 	debug_deactivate(timer);  in __run_hrtimer()
1770 	base->running = timer;  in __run_hrtimer()
1777 	 * timer->state == INACTIVE.  in __run_hrtimer()
1781 	__remove_hrtimer(timer, base, HRTIMER_STATE_INACTIVE, 0);  in __run_hrtimer()
1782 	fn = timer->function;  in __run_hrtimer()
1786 	 * timer is restarted with a period then it becomes an absolute  in __run_hrtimer()
1787 	 * timer. If its not restarted it does not matter.  in __run_hrtimer()
1790 		timer->is_rel = false;  in __run_hrtimer()
1793 	 * The timer is marked as running in the CPU base, so it is  in __run_hrtimer()
1798 	trace_hrtimer_expire_entry(timer, now);  in __run_hrtimer()
1799 	expires_in_hardirq = lockdep_hrtimer_enter(timer);  in __run_hrtimer()
1801 	restart = fn(timer);  in __run_hrtimer()
1804 	trace_hrtimer_expire_exit(timer);  in __run_hrtimer()
1813 	 * hrtimer_start_range_ns() can have popped in and enqueued the timer  in __run_hrtimer()
1817 	    !(timer->state & HRTIMER_STATE_ENQUEUED))  in __run_hrtimer()
1818 		enqueue_hrtimer(timer, base, HRTIMER_MODE_ABS);  in __run_hrtimer()
1824 	 * hrtimer_active() cannot observe base->running.timer == NULL &&  in __run_hrtimer()
1825 	 * timer->state == INACTIVE.  in __run_hrtimer()
1829 	WARN_ON_ONCE(base->running != timer);  in __run_hrtimer()
1846 			struct hrtimer *timer;  in __hrtimer_run_queues()  local
1848 			timer = container_of(node, struct hrtimer, node);  in __hrtimer_run_queues()
1859 			 * are right-of a not yet expired timer, because that  in __hrtimer_run_queues()
1860 			 * timer will have to trigger a wakeup anyway.  in __hrtimer_run_queues()
1862 			if (basenow < hrtimer_get_softexpires_tv64(timer))  in __hrtimer_run_queues()
1865 			__run_hrtimer(cpu_base, base, timer, &basenow, flags);  in __hrtimer_run_queues()
1894  * High resolution timer interrupt
1914 	 * held to prevent that a timer is enqueued in our queue via  in hrtimer_interrupt()
1946 	 * The next timer was already expired due to:  in hrtimer_interrupt()
2029 static enum hrtimer_restart hrtimer_wakeup(struct hrtimer *timer)  in hrtimer_wakeup()  argument
2032 		container_of(timer, struct hrtimer_sleeper, timer);  in hrtimer_wakeup()
2043  * hrtimer_sleeper_start_expires - Start a hrtimer sleeper timer
2045  * @mode:	timer mode abs/rel
2060 	if (IS_ENABLED(CONFIG_PREEMPT_RT) && sl->timer.is_hard)  in hrtimer_sleeper_start_expires()
2063 	hrtimer_start_expires(&sl->timer, mode);  in hrtimer_sleeper_start_expires()
2094 	__hrtimer_init(&sl->timer, clock_id, mode);  in __hrtimer_init_sleeper()
2095 	sl->timer.function = hrtimer_wakeup;  in __hrtimer_init_sleeper()
2103  * @mode:	timer mode abs/rel
2108 	debug_init_on_stack(&sl->timer, clock_id, mode);  in hrtimer_setup_sleeper_on_stack()
2143 		hrtimer_cancel(&t->timer);  in do_nanosleep()
2155 		ktime_t rem = hrtimer_expires_remaining(&t->timer);  in do_nanosleep()
2173 	hrtimer_set_expires_tv64(&t.timer, restart->nanosleep.expires);  in hrtimer_nanosleep_restart()
2175 	destroy_hrtimer_on_stack(&t.timer);  in hrtimer_nanosleep_restart()
2187 	hrtimer_set_expires_range_ns(&t.timer, rqtp, current->timer_slack_ns);  in hrtimer_nanosleep()
2199 	restart->nanosleep.clockid = t.timer.base->clockid;  in hrtimer_nanosleep()
2200 	restart->nanosleep.expires = hrtimer_get_expires_tv64(&t.timer);  in hrtimer_nanosleep()
2203 	destroy_hrtimer_on_stack(&t.timer);  in hrtimer_nanosleep()
2292 	struct hrtimer *timer;  in migrate_hrtimer_list()  local
2296 		timer = container_of(node, struct hrtimer, node);  in migrate_hrtimer_list()
2297 		BUG_ON(hrtimer_callback_running(timer));  in migrate_hrtimer_list()
2298 		debug_deactivate(timer);  in migrate_hrtimer_list()
2302 		 * timer could be seen as !active and just vanish away  in migrate_hrtimer_list()
2305 		__remove_hrtimer(timer, old_base, HRTIMER_STATE_ENQUEUED, 0);  in migrate_hrtimer_list()
2306 		timer->base = new_base;  in migrate_hrtimer_list()
2309 		 * reprogram the event device in case the timer  in migrate_hrtimer_list()
2315 		enqueue_hrtimer(timer, new_base, HRTIMER_MODE_ABS);  in migrate_hrtimer_list()
2341 	 * timer on this CPU. Update it.  in hrtimers_cpu_dying()