// SPDX-License-Identifier: GPL-2.0/* * Alarmtimer interface * * This interface provides a timer which is similarto hrtimers, * but triggers a RTC alarm if the box is suspend. * * This interface is influenced by the Android RTC Alarm timer * interface. * * Copyright (C) 2010 IBM Corperation * * Author: John Stultz <john.stultz@linaro.org> */#include <linux/time.h>#include <linux/hrtimer.h>#include <linux/timerqueue.h>#include <linux/rtc.h>#include <linux/sched/signal.h>#include <linux/sched/debug.h>#include <linux/alarmtimer.h>#include <linux/mutex.h>#include <linux/platform_device.h>#include <linux/posix-timers.h>#include <linux/workqueue.h>#include <linux/freezer.h>#include <linux/compat.h>#include <linux/module.h>#include <linux/time_namespace.h> #include "posix-timers.h" #define CREATE_TRACE_POINTS#include <trace/events/alarmtimer.h> /** * struct alarm_base - Alarm timer bases * @lock: Lock for syncrhonized access to the base * @timerqueue: Timerqueue head managing the list of events * @get_ktime: Function to read the time correlating to the base * @get_timespec: Function to read the namespace time correlating to the base * @base_clockid: clockid for the base */static struct alarm_base { spinlock_t lock; struct timerqueue_head timerqueue; ktime_t (*get_ktime)(void); void (*get_timespec)(struct timespec64 *tp); clockid_t base_clockid;} alarm_bases[ALARM_NUMTYPE]; #if defined(CONFIG_POSIX_TIMERS) || defined(CONFIG_RTC_CLASS)/* freezer information to handle clock_nanosleep triggered wakeups */static enum alarmtimer_type freezer_alarmtype;static ktime_t freezer_expires;static ktime_t freezer_delta;static DEFINE_SPINLOCK(freezer_delta_lock);#endif #ifdef CONFIG_RTC_CLASS/* rtc timer and device for setting alarm wakeups at suspend */static struct rtc_timer rtctimer;static struct rtc_device *rtcdev;static DEFINE_SPINLOCK(rtcdev_lock); /** * alarmtimer_get_rtcdev - Return selected rtcdevice * * This function returns the rtc device to use for wakealarms. */struct rtc_device *alarmtimer_get_rtcdev(void){ unsigned long flags; struct rtc_device *ret; spin_lock_irqsave(&rtcdev_lock, flags); ret = rtcdev; spin_unlock_irqrestore(&rtcdev_lock, flags); return ret;}EXPORT_SYMBOL_GPL(alarmtimer_get_rtcdev); static int alarmtimer_rtc_add_device(struct device *dev, struct class_interface *class_intf){ unsigned long flags; struct rtc_device *rtc = to_rtc_device(dev); struct platform_device *pdev; int ret = 0; if (rtcdev) return -EBUSY; if (!rtc->ops->set_alarm) return -1; if (!device_may_wakeup(rtc->dev.parent)) return -1; pdev = platform_device_register_data(dev, "alarmtimer", PLATFORM_DEVID_AUTO, NULL, 0); if (!IS_ERR(pdev)) device_init_wakeup(&pdev->dev, true); spin_lock_irqsave(&rtcdev_lock, flags); if (!IS_ERR(pdev) && !rtcdev) { if (!try_module_get(rtc->owner)) { ret = -1; goto unlock; } rtcdev = rtc; /* hold a reference so it doesn't go away */ get_device(dev); pdev = NULL; } else { ret = -1; }unlock: spin_unlock_irqrestore(&rtcdev_lock, flags); platform_device_unregister(pdev); return ret;} static inline void alarmtimer_rtc_timer_init(void){ rtc_timer_init(&rtctimer, NULL, NULL);} static struct class_interface alarmtimer_rtc_interface = { .add_dev = &alarmtimer_rtc_add_device,}; static int alarmtimer_rtc_interface_setup(void){ alarmtimer_rtc_interface.class = rtc_class; return class_interface_register(&alarmtimer_rtc_interface);}static void alarmtimer_rtc_interface_remove(void){ class_interface_unregister(&alarmtimer_rtc_interface);}#elsestatic inline int alarmtimer_rtc_interface_setup(void) { return 0; }static inline void alarmtimer_rtc_interface_remove(void) { }static inline void alarmtimer_rtc_timer_init(void) { }#endif /** * alarmtimer_enqueue - Adds an alarm timer to an alarm_base timerqueue * @base: pointer to the base where the timer is being run * @alarm: pointer to alarm being enqueued. * * Adds alarm to a alarm_base timerqueue * * Must hold base->lock when calling. */static void alarmtimer_enqueue(struct alarm_base *base, struct alarm *alarm){ if (alarm->state & ALARMTIMER_STATE_ENQUEUED) timerqueue_del(&base->timerqueue, &alarm->node); timerqueue_add(&base->timerqueue, &alarm->node); alarm->state |= ALARMTIMER_STATE_ENQUEUED;} /** * alarmtimer_dequeue - Removes an alarm timer from an alarm_base timerqueue * @base: pointer to the base where the timer is running * @alarm: pointer to alarm being removed * * Removes alarm to a alarm_base timerqueue * * Must hold base->lock when calling. */static void alarmtimer_dequeue(struct alarm_base *base, struct alarm *alarm){ if (!(alarm->state & ALARMTIMER_STATE_ENQUEUED)) return; timerqueue_del(&base->timerqueue, &alarm->node); alarm->state &= ~ALARMTIMER_STATE_ENQUEUED;} /** * alarmtimer_fired - Handles alarm hrtimer being fired. * @timer: pointer to hrtimer being run * * When a alarm timer fires, this runs through the timerqueue to * see which alarms expired, and runs those. If there are more alarm * timers queued for the future, we set the hrtimer to fire when * the next future alarm timer expires. */static enum hrtimer_restart alarmtimer_fired(struct hrtimer *timer){ struct alarm *alarm = container_of(timer, struct alarm, timer); struct alarm_base *base = &alarm_bases[alarm->type]; unsigned long flags; int ret = HRTIMER_NORESTART; int restart = ALARMTIMER_NORESTART; spin_lock_irqsave(&base->lock, flags); alarmtimer_dequeue(base, alarm); spin_unlock_irqrestore(&base->lock, flags); if (alarm->function) restart = alarm->function(alarm, base->get_ktime()); spin_lock_irqsave(&base->lock, flags); if (restart != ALARMTIMER_NORESTART) { hrtimer_set_expires(&alarm->timer, alarm->node.expires); alarmtimer_enqueue(base, alarm); ret = HRTIMER_RESTART; } spin_unlock_irqrestore(&base->lock, flags); trace_alarmtimer_fired(alarm, base->get_ktime()); return ret; } ktime_t alarm_expires_remaining(const struct alarm *alarm){ struct alarm_base *base = &alarm_bases[alarm->type]; return ktime_sub(alarm->node.expires, base->get_ktime());}EXPORT_SYMBOL_GPL(alarm_expires_remaining); #ifdef CONFIG_RTC_CLASS/** * alarmtimer_suspend - Suspend time callback * @dev: unused * * When we are going into suspend, we look through the bases * to see which is the soonest timer to expire. We then * set an rtc timer to fire that far into the future, which * will wake us from suspend. */static int alarmtimer_suspend(struct device *dev){ ktime_t min, now, expires; int i, ret, type; struct rtc_device *rtc; unsigned long flags; struct rtc_time tm; spin_lock_irqsave(&freezer_delta_lock, flags); min = freezer_delta; expires = freezer_expires; type = freezer_alarmtype; freezer_delta = 0; spin_unlock_irqrestore(&freezer_delta_lock, flags); rtc = alarmtimer_get_rtcdev(); /* If we have no rtcdev, just return */ if (!rtc) return 0; /* Find the soonest timer to expire*/ for (i = 0; i < ALARM_NUMTYPE; i++) { struct alarm_base *base = &alarm_bases[i]; struct timerqueue_node *next; ktime_t delta; spin_lock_irqsave(&base->lock, flags); next = timerqueue_getnext(&base->timerqueue); spin_unlock_irqrestore(&base->lock, flags); if (!next) continue; delta = ktime_sub(next->expires, base->get_ktime()); if (!min || (delta < min)) { expires = next->expires; min = delta; type = i; } } if (min == 0) return 0; if (ktime_to_ns(min) < 2 * NSEC_PER_SEC) { pm_wakeup_event(dev, 2 * MSEC_PER_SEC); return -EBUSY; } trace_alarmtimer_suspend(expires, type); /* Setup an rtc timer to fire that far in the future */ rtc_timer_cancel(rtc, &rtctimer); rtc_read_time(rtc, &tm); now = rtc_tm_to_ktime(tm); now = ktime_add(now, min); /* Set alarm, if in the past reject suspend briefly to handle */ ret = rtc_timer_start(rtc, &rtctimer, now, 0); if (ret < 0) pm_wakeup_event(dev, MSEC_PER_SEC); return ret;} static int alarmtimer_resume(struct device *dev){ struct rtc_device *rtc; rtc = alarmtimer_get_rtcdev(); if (rtc) rtc_timer_cancel(rtc, &rtctimer); return 0;} #elsestatic int alarmtimer_suspend(struct device *dev){ return 0;} static int alarmtimer_resume(struct device *dev){ return 0;}#endif static void__alarm_init(struct alarm *alarm, enum alarmtimer_type type, enum alarmtimer_restart (*function)(struct alarm *, ktime_t)){ timerqueue_init(&alarm->node); alarm->timer.function = alarmtimer_fired; alarm->function = function; alarm->type = type; alarm->state = ALARMTIMER_STATE_INACTIVE;} /** * alarm_init - Initialize an alarm structure * @alarm: ptr to alarm to be initialized * @type: the type of the alarm * @function: callback that is run when the alarm fires */void alarm_init(struct alarm *alarm, enum alarmtimer_type type, enum alarmtimer_restart (*function)(struct alarm *, ktime_t)){ hrtimer_init(&alarm->timer, alarm_bases[type].base_clockid, HRTIMER_MODE_ABS); __alarm_init(alarm, type, function);}EXPORT_SYMBOL_GPL(alarm_init); /** * alarm_start - Sets an absolute alarm to fire * @alarm: ptr to alarm to set * @start: time to run the alarm */void alarm_start(struct alarm *alarm, ktime_t start){ struct alarm_base *base = &alarm_bases[alarm->type]; unsigned long flags; spin_lock_irqsave(&base->lock, flags); alarm->node.expires = start; alarmtimer_enqueue(base, alarm); hrtimer_start(&alarm->timer, alarm->node.expires, HRTIMER_MODE_ABS); spin_unlock_irqrestore(&base->lock, flags); trace_alarmtimer_start(alarm, base->get_ktime());}EXPORT_SYMBOL_GPL(alarm_start); /** * alarm_start_relative - Sets a relative alarm to fire * @alarm: ptr to alarm to set * @start: time relative to now to run the alarm */void alarm_start_relative(struct alarm *alarm, ktime_t start){ struct alarm_base *base = &alarm_bases[alarm->type]; start = ktime_add_safe(start, base->get_ktime()); alarm_start(alarm, start);}EXPORT_SYMBOL_GPL(alarm_start_relative); void alarm_restart(struct alarm *alarm){ struct alarm_base *base = &alarm_bases[alarm->type]; unsigned long flags; spin_lock_irqsave(&base->lock, flags); hrtimer_set_expires(&alarm->timer, alarm->node.expires); hrtimer_restart(&alarm->timer); alarmtimer_enqueue(base, alarm); spin_unlock_irqrestore(&base->lock, flags);}EXPORT_SYMBOL_GPL(alarm_restart); /** * alarm_try_to_cancel - Tries to cancel an alarm timer * @alarm: ptr to alarm to be canceled * * Returns 1 if the timer was canceled, 0 if it was not running, * and -1 if the callback was running */int alarm_try_to_cancel(struct alarm *alarm){ struct alarm_base *base = &alarm_bases[alarm->type]; unsigned long flags; int ret; spin_lock_irqsave(&base->lock, flags); ret = hrtimer_try_to_cancel(&alarm->timer); if (ret >= 0) alarmtimer_dequeue(base, alarm); spin_unlock_irqrestore(&base->lock, flags); trace_alarmtimer_cancel(alarm, base->get_ktime()); return ret;}EXPORT_SYMBOL_GPL(alarm_try_to_cancel); /** * alarm_cancel - Spins trying to cancel an alarm timer until it is done * @alarm: ptr to alarm to be canceled * * Returns 1 if the timer was canceled, 0 if it was not active. */int alarm_cancel(struct alarm *alarm){ for (;;) { int ret = alarm_try_to_cancel(alarm); if (ret >= 0) return ret; hrtimer_cancel_wait_running(&alarm->timer); }}EXPORT_SYMBOL_GPL(alarm_cancel); u64 alarm_forward(struct alarm *alarm, ktime_t now, ktime_t interval){ u64 overrun = 1; ktime_t delta; delta = ktime_sub(now, alarm->node.expires); if (delta < 0) return 0; if (unlikely(delta >= interval)) { s64 incr = ktime_to_ns(interval); overrun = ktime_divns(delta, incr); alarm->node.expires = ktime_add_ns(alarm->node.expires, incr*overrun); if (alarm->node.expires > now) return overrun; /* * This (and the ktime_add() below) is the * correction for exact: */ overrun++; } alarm->node.expires = ktime_add_safe(alarm->node.expires, interval); return overrun;}EXPORT_SYMBOL_GPL(alarm_forward); u64 alarm_forward_now(struct alarm *alarm, ktime_t interval){ struct alarm_base *base = &alarm_bases[alarm->type]; return alarm_forward(alarm, base->get_ktime(), interval);}EXPORT_SYMBOL_GPL(alarm_forward_now); #ifdef CONFIG_POSIX_TIMERS static void alarmtimer_freezerset(ktime_t absexp, enum alarmtimer_type type){ struct alarm_base *base; unsigned long flags; ktime_t delta; switch(type) { case ALARM_REALTIME: base = &alarm_bases[ALARM_REALTIME]; type = ALARM_REALTIME_FREEZER; break; case ALARM_BOOTTIME: base = &alarm_bases[ALARM_BOOTTIME]; type = ALARM_BOOTTIME_FREEZER; break; default: WARN_ONCE(1, "Invalid alarm type: %d\n", type); return;Lines 1–500 of 933. 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// SPDX-License-Identifier: GPL-2.0 /* * Alarmtimer interface * * This interface provides a timer which is similarto hrtimers, * but triggers a RTC alarm if the box is suspend. * * This interface is influenced by the Android RTC Alarm timer * interface. * * Copyright (C) 2010 IBM Corperation * * Author: John Stultz <john.stultz@linaro.org> */ #include <linux/time.h> #include <linux/hrtimer.h> #include <linux/timerqueue.h> #include <linux/rtc.h> #include <linux/sched/signal.h> #include <linux/sched/debug.h> #include <linux/alarmtimer.h> #include <linux/mutex.h> #include <linux/platform_device.h> #include <linux/posix-timers.h> #include <linux/workqueue.h> #include <linux/freezer.h> #include <linux/compat.h> #include <linux/module.h> #include <linux/time_namespace.h> #include "posix-timers.h" #define CREATE_TRACE_POINTS #include <trace/events/alarmtimer.h> /** * struct alarm_base - Alarm timer bases * @lock: Lock for syncrhonized access to the base * @timerqueue: Timerqueue head managing the list of events * @get_ktime: Function to read the time correlating to the base * @get_timespec: Function to read the namespace time correlating to the base * @base_clockid: clockid for the base */ static struct alarm_base { spinlock_t lock; struct timerqueue_head timerqueue; ktime_t (*get_ktime)(void); void (*get_timespec)(struct timespec64 *tp); clockid_t base_clockid; } alarm_bases[ALARM_NUMTYPE]; #if defined(CONFIG_POSIX_TIMERS) || defined(CONFIG_RTC_CLASS) /* freezer information to handle clock_nanosleep triggered wakeups */ static enum alarmtimer_type freezer_alarmtype; static ktime_t freezer_expires; static ktime_t freezer_delta; static DEFINE_SPINLOCK(freezer_delta_lock); #endif #ifdef CONFIG_RTC_CLASS /* rtc timer and device for setting alarm wakeups at suspend */ static struct rtc_timer rtctimer; static struct rtc_device *rtcdev; static DEFINE_SPINLOCK(rtcdev_lock); /** * alarmtimer_get_rtcdev - Return selected rtcdevice * * This function returns the rtc device to use for wakealarms. */ struct rtc_device *alarmtimer_get_rtcdev(void) { unsigned long flags; struct rtc_device *ret; spin_lock_irqsave(&rtcdev_lock, flags); ret = rtcdev; spin_unlock_irqrestore(&rtcdev_lock, flags); return ret; } EXPORT_SYMBOL_GPL(alarmtimer_get_rtcdev); static int alarmtimer_rtc_add_device(struct device *dev, struct class_interface *class_intf) { unsigned long flags; struct rtc_device *rtc = to_rtc_device(dev); struct platform_device *pdev; int ret = 0; if (rtcdev) return -EBUSY; if (!rtc->ops->set_alarm) return -1; if (!device_may_wakeup(rtc->dev.parent)) return -1; pdev = platform_device_register_data(dev, "alarmtimer", PLATFORM_DEVID_AUTO, NULL, 0); if (!IS_ERR(pdev)) device_init_wakeup(&pdev->dev, true); spin_lock_irqsave(&rtcdev_lock, flags); if (!IS_ERR(pdev) && !rtcdev) { if (!try_module_get(rtc->owner)) { ret = -1; goto unlock; } rtcdev = rtc; /* hold a reference so it doesn't go away */ get_device(dev); pdev = NULL; } else { ret = -1; } unlock: spin_unlock_irqrestore(&rtcdev_lock, flags); platform_device_unregister(pdev); return ret; } static inline void alarmtimer_rtc_timer_init(void) { rtc_timer_init(&rtctimer, NULL, NULL); } static struct class_interface alarmtimer_rtc_interface = { .add_dev = &alarmtimer_rtc_add_device, }; static int alarmtimer_rtc_interface_setup(void) { alarmtimer_rtc_interface.class = rtc_class; return class_interface_register(&alarmtimer_rtc_interface); } static void alarmtimer_rtc_interface_remove(void) { class_interface_unregister(&alarmtimer_rtc_interface); } #else static inline int alarmtimer_rtc_interface_setup(void) { return 0; } static inline void alarmtimer_rtc_interface_remove(void) { } static inline void alarmtimer_rtc_timer_init(void) { } #endif /** * alarmtimer_enqueue - Adds an alarm timer to an alarm_base timerqueue * @base: pointer to the base where the timer is being run * @alarm: pointer to alarm being enqueued. * * Adds alarm to a alarm_base timerqueue * * Must hold base->lock when calling. */ static void alarmtimer_enqueue(struct alarm_base *base, struct alarm *alarm) { if (alarm->state & ALARMTIMER_STATE_ENQUEUED) timerqueue_del(&base->timerqueue, &alarm->node); timerqueue_add(&base->timerqueue, &alarm->node); alarm->state |= ALARMTIMER_STATE_ENQUEUED; } /** * alarmtimer_dequeue - Removes an alarm timer from an alarm_base timerqueue * @base: pointer to the base where the timer is running * @alarm: pointer to alarm being removed * * Removes alarm to a alarm_base timerqueue * * Must hold base->lock when calling. */ static void alarmtimer_dequeue(struct alarm_base *base, struct alarm *alarm) { if (!(alarm->state & ALARMTIMER_STATE_ENQUEUED)) return; timerqueue_del(&base->timerqueue, &alarm->node); alarm->state &= ~ALARMTIMER_STATE_ENQUEUED; } /** * alarmtimer_fired - Handles alarm hrtimer being fired. * @timer: pointer to hrtimer being run * * When a alarm timer fires, this runs through the timerqueue to * see which alarms expired, and runs those. If there are more alarm * timers queued for the future, we set the hrtimer to fire when * the next future alarm timer expires. */ static enum hrtimer_restart alarmtimer_fired(struct hrtimer *timer) { struct alarm *alarm = container_of(timer, struct alarm, timer); struct alarm_base *base = &alarm_bases[alarm->type]; unsigned long flags; int ret = HRTIMER_NORESTART; int restart = ALARMTIMER_NORESTART; spin_lock_irqsave(&base->lock, flags); alarmtimer_dequeue(base, alarm); spin_unlock_irqrestore(&base->lock, flags); if (alarm->function) restart = alarm->function(alarm, base->get_ktime()); spin_lock_irqsave(&base->lock, flags); if (restart != ALARMTIMER_NORESTART) { hrtimer_set_expires(&alarm->timer, alarm->node.expires); alarmtimer_enqueue(base, alarm); ret = HRTIMER_RESTART; } spin_unlock_irqrestore(&base->lock, flags); trace_alarmtimer_fired(alarm, base->get_ktime()); return ret; } ktime_t alarm_expires_remaining(const struct alarm *alarm) { struct alarm_base *base = &alarm_bases[alarm->type]; return ktime_sub(alarm->node.expires, base->get_ktime()); } EXPORT_SYMBOL_GPL(alarm_expires_remaining); #ifdef CONFIG_RTC_CLASS /** * alarmtimer_suspend - Suspend time callback * @dev: unused * * When we are going into suspend, we look through the bases * to see which is the soonest timer to expire. We then * set an rtc timer to fire that far into the future, which * will wake us from suspend. */ static int alarmtimer_suspend(struct device *dev) { ktime_t min, now, expires; int i, ret, type; struct rtc_device *rtc; unsigned long flags; struct rtc_time tm; spin_lock_irqsave(&freezer_delta_lock, flags); min = freezer_delta; expires = freezer_expires; type = freezer_alarmtype; freezer_delta = 0; spin_unlock_irqrestore(&freezer_delta_lock, flags); rtc = alarmtimer_get_rtcdev(); /* If we have no rtcdev, just return */ if (!rtc) return 0; /* Find the soonest timer to expire*/ for (i = 0; i < ALARM_NUMTYPE; i++) { struct alarm_base *base = &alarm_bases[i]; struct timerqueue_node *next; ktime_t delta; spin_lock_irqsave(&base->lock, flags); next = timerqueue_getnext(&base->timerqueue); spin_unlock_irqrestore(&base->lock, flags); if (!next) continue; delta = ktime_sub(next->expires, base->get_ktime()); if (!min || (delta < min)) { expires = next->expires; min = delta; type = i; } } if (min == 0) return 0; if (ktime_to_ns(min) < 2 * NSEC_PER_SEC) { pm_wakeup_event(dev, 2 * MSEC_PER_SEC); return -EBUSY; } trace_alarmtimer_suspend(expires, type); /* Setup an rtc timer to fire that far in the future */ rtc_timer_cancel(rtc, &rtctimer); rtc_read_time(rtc, &tm); now = rtc_tm_to_ktime(tm); now = ktime_add(now, min); /* Set alarm, if in the past reject suspend briefly to handle */ ret = rtc_timer_start(rtc, &rtctimer, now, 0); if (ret < 0) pm_wakeup_event(dev, MSEC_PER_SEC); return ret; } static int alarmtimer_resume(struct device *dev) { struct rtc_device *rtc; rtc = alarmtimer_get_rtcdev(); if (rtc) rtc_timer_cancel(rtc, &rtctimer); return 0; } #else static int alarmtimer_suspend(struct device *dev) { return 0; } static int alarmtimer_resume(struct device *dev) { return 0; } #endif static void __alarm_init(struct alarm *alarm, enum alarmtimer_type type, enum alarmtimer_restart (*function)(struct alarm *, ktime_t)) { timerqueue_init(&alarm->node); alarm->timer.function = alarmtimer_fired; alarm->function = function; alarm->type = type; alarm->state = ALARMTIMER_STATE_INACTIVE; } /** * alarm_init - Initialize an alarm structure * @alarm: ptr to alarm to be initialized * @type: the type of the alarm * @function: callback that is run when the alarm fires */ void alarm_init(struct alarm *alarm, enum alarmtimer_type type, enum alarmtimer_restart (*function)(struct alarm *, ktime_t)) { hrtimer_init(&alarm->timer, alarm_bases[type].base_clockid, HRTIMER_MODE_ABS); __alarm_init(alarm, type, function); } EXPORT_SYMBOL_GPL(alarm_init); /** * alarm_start - Sets an absolute alarm to fire * @alarm: ptr to alarm to set * @start: time to run the alarm */ void alarm_start(struct alarm *alarm, ktime_t start) { struct alarm_base *base = &alarm_bases[alarm->type]; unsigned long flags; spin_lock_irqsave(&base->lock, flags); alarm->node.expires = start; alarmtimer_enqueue(base, alarm); hrtimer_start(&alarm->timer, alarm->node.expires, HRTIMER_MODE_ABS); spin_unlock_irqrestore(&base->lock, flags); trace_alarmtimer_start(alarm, base->get_ktime()); } EXPORT_SYMBOL_GPL(alarm_start); /** * alarm_start_relative - Sets a relative alarm to fire * @alarm: ptr to alarm to set * @start: time relative to now to run the alarm */ void alarm_start_relative(struct alarm *alarm, ktime_t start) { struct alarm_base *base = &alarm_bases[alarm->type]; start = ktime_add_safe(start, base->get_ktime()); alarm_start(alarm, start); } EXPORT_SYMBOL_GPL(alarm_start_relative); void alarm_restart(struct alarm *alarm) { struct alarm_base *base = &alarm_bases[alarm->type]; unsigned long flags; spin_lock_irqsave(&base->lock, flags); hrtimer_set_expires(&alarm->timer, alarm->node.expires); hrtimer_restart(&alarm->timer); alarmtimer_enqueue(base, alarm); spin_unlock_irqrestore(&base->lock, flags); } EXPORT_SYMBOL_GPL(alarm_restart); /** * alarm_try_to_cancel - Tries to cancel an alarm timer * @alarm: ptr to alarm to be canceled * * Returns 1 if the timer was canceled, 0 if it was not running, * and -1 if the callback was running */ int alarm_try_to_cancel(struct alarm *alarm) { struct alarm_base *base = &alarm_bases[alarm->type]; unsigned long flags; int ret; spin_lock_irqsave(&base->lock, flags); ret = hrtimer_try_to_cancel(&alarm->timer); if (ret >= 0) alarmtimer_dequeue(base, alarm); spin_unlock_irqrestore(&base->lock, flags); trace_alarmtimer_cancel(alarm, base->get_ktime()); return ret; } EXPORT_SYMBOL_GPL(alarm_try_to_cancel); /** * alarm_cancel - Spins trying to cancel an alarm timer until it is done * @alarm: ptr to alarm to be canceled * * Returns 1 if the timer was canceled, 0 if it was not active. */ int alarm_cancel(struct alarm *alarm) { for (;;) { int ret = alarm_try_to_cancel(alarm); if (ret >= 0) return ret; hrtimer_cancel_wait_running(&alarm->timer); } } EXPORT_SYMBOL_GPL(alarm_cancel); u64 alarm_forward(struct alarm *alarm, ktime_t now, ktime_t interval) { u64 overrun = 1; ktime_t delta; delta = ktime_sub(now, alarm->node.expires); if (delta < 0) return 0; if (unlikely(delta >= interval)) { s64 incr = ktime_to_ns(interval); overrun = ktime_divns(delta, incr); alarm->node.expires = ktime_add_ns(alarm->node.expires, incr*overrun); if (alarm->node.expires > now) return overrun; /* * This (and the ktime_add() below) is the * correction for exact: */ overrun++; } alarm->node.expires = ktime_add_safe(alarm->node.expires, interval); return overrun; } EXPORT_SYMBOL_GPL(alarm_forward); u64 alarm_forward_now(struct alarm *alarm, ktime_t interval) { struct alarm_base *base = &alarm_bases[alarm->type]; return alarm_forward(alarm, base->get_ktime(), interval); } EXPORT_SYMBOL_GPL(alarm_forward_now); #ifdef CONFIG_POSIX_TIMERS static void alarmtimer_freezerset(ktime_t absexp, enum alarmtimer_type type) { struct alarm_base *base; unsigned long flags; ktime_t delta; switch(type) { case ALARM_REALTIME: base = &alarm_bases[ALARM_REALTIME]; type = ALARM_REALTIME_FREEZER; break; case ALARM_BOOTTIME: base = &alarm_bases[ALARM_BOOTTIME]; type = ALARM_BOOTTIME_FREEZER; break; default: WARN_ONCE(1, "Invalid alarm type: %d\n", type); return;