2 * linux/kernel/time/tick-broadcast.c
4 * This file contains functions which emulate a local clock-event
5 * device via a broadcast event source.
7 * Copyright(C) 2005-2006, Thomas Gleixner <tglx@linutronix.de>
8 * Copyright(C) 2005-2007, Red Hat, Inc., Ingo Molnar
9 * Copyright(C) 2006-2007, Timesys Corp., Thomas Gleixner
11 * This code is licenced under the GPL version 2. For details see
12 * kernel-base/COPYING.
14 #include <linux/cpu.h>
15 #include <linux/err.h>
16 #include <linux/hrtimer.h>
17 #include <linux/interrupt.h>
18 #include <linux/percpu.h>
19 #include <linux/profile.h>
20 #include <linux/sched.h>
21 #include <linux/smp.h>
22 #include <linux/module.h>
24 #include "tick-internal.h"
27 * Broadcast support for broken x86 hardware, where the local apic
28 * timer stops in C3 state.
31 static struct tick_device tick_broadcast_device;
32 static cpumask_var_t tick_broadcast_mask;
33 static cpumask_var_t tick_broadcast_on;
34 static cpumask_var_t tmpmask;
35 static DEFINE_RAW_SPINLOCK(tick_broadcast_lock);
36 static int tick_broadcast_force;
38 #ifdef CONFIG_TICK_ONESHOT
39 static void tick_broadcast_clear_oneshot(int cpu);
41 static inline void tick_broadcast_clear_oneshot(int cpu) { }
45 * Debugging: see timer_list.c
47 struct tick_device *tick_get_broadcast_device(void)
49 return &tick_broadcast_device;
52 struct cpumask *tick_get_broadcast_mask(void)
54 return tick_broadcast_mask;
58 * Start the device in periodic mode
60 static void tick_broadcast_start_periodic(struct clock_event_device *bc)
63 tick_setup_periodic(bc, 1);
67 * Check, if the device can be utilized as broadcast device:
69 static bool tick_check_broadcast_device(struct clock_event_device *curdev,
70 struct clock_event_device *newdev)
72 if ((newdev->features & CLOCK_EVT_FEAT_DUMMY) ||
73 (newdev->features & CLOCK_EVT_FEAT_C3STOP))
76 if (tick_broadcast_device.mode == TICKDEV_MODE_ONESHOT &&
77 !(newdev->features & CLOCK_EVT_FEAT_ONESHOT))
80 return !curdev || newdev->rating > curdev->rating;
84 * Conditionally install/replace broadcast device
86 void tick_install_broadcast_device(struct clock_event_device *dev)
88 struct clock_event_device *cur = tick_broadcast_device.evtdev;
90 if (!tick_check_broadcast_device(cur, dev))
93 if (!try_module_get(dev->owner))
96 clockevents_exchange_device(cur, dev);
98 cur->event_handler = clockevents_handle_noop;
99 tick_broadcast_device.evtdev = dev;
100 if (!cpumask_empty(tick_broadcast_mask))
101 tick_broadcast_start_periodic(dev);
103 * Inform all cpus about this. We might be in a situation
104 * where we did not switch to oneshot mode because the per cpu
105 * devices are affected by CLOCK_EVT_FEAT_C3STOP and the lack
106 * of a oneshot capable broadcast device. Without that
107 * notification the systems stays stuck in periodic mode
110 if (dev->features & CLOCK_EVT_FEAT_ONESHOT)
115 * Check, if the device is the broadcast device
117 int tick_is_broadcast_device(struct clock_event_device *dev)
119 return (dev && tick_broadcast_device.evtdev == dev);
122 static void err_broadcast(const struct cpumask *mask)
124 pr_crit_once("Failed to broadcast timer tick. Some CPUs may be unresponsive.\n");
127 static void tick_device_setup_broadcast_func(struct clock_event_device *dev)
130 dev->broadcast = tick_broadcast;
131 if (!dev->broadcast) {
132 pr_warn_once("%s depends on broadcast, but no broadcast function available\n",
134 dev->broadcast = err_broadcast;
139 * Check, if the device is disfunctional and a place holder, which
140 * needs to be handled by the broadcast device.
142 int tick_device_uses_broadcast(struct clock_event_device *dev, int cpu)
144 struct clock_event_device *bc = tick_broadcast_device.evtdev;
148 raw_spin_lock_irqsave(&tick_broadcast_lock, flags);
151 * Devices might be registered with both periodic and oneshot
152 * mode disabled. This signals, that the device needs to be
153 * operated from the broadcast device and is a placeholder for
154 * the cpu local device.
156 if (!tick_device_is_functional(dev)) {
157 dev->event_handler = tick_handle_periodic;
158 tick_device_setup_broadcast_func(dev);
159 cpumask_set_cpu(cpu, tick_broadcast_mask);
160 if (tick_broadcast_device.mode == TICKDEV_MODE_PERIODIC)
161 tick_broadcast_start_periodic(bc);
163 tick_broadcast_setup_oneshot(bc);
167 * Clear the broadcast bit for this cpu if the
168 * device is not power state affected.
170 if (!(dev->features & CLOCK_EVT_FEAT_C3STOP))
171 cpumask_clear_cpu(cpu, tick_broadcast_mask);
173 tick_device_setup_broadcast_func(dev);
176 * Clear the broadcast bit if the CPU is not in
177 * periodic broadcast on state.
179 if (!cpumask_test_cpu(cpu, tick_broadcast_on))
180 cpumask_clear_cpu(cpu, tick_broadcast_mask);
182 switch (tick_broadcast_device.mode) {
183 case TICKDEV_MODE_ONESHOT:
185 * If the system is in oneshot mode we can
186 * unconditionally clear the oneshot mask bit,
187 * because the CPU is running and therefore
188 * not in an idle state which causes the power
189 * state affected device to stop. Let the
190 * caller initialize the device.
192 tick_broadcast_clear_oneshot(cpu);
196 case TICKDEV_MODE_PERIODIC:
198 * If the system is in periodic mode, check
199 * whether the broadcast device can be
202 if (cpumask_empty(tick_broadcast_mask) && bc)
203 clockevents_shutdown(bc);
205 * If we kept the cpu in the broadcast mask,
206 * tell the caller to leave the per cpu device
207 * in shutdown state. The periodic interrupt
208 * is delivered by the broadcast device.
210 ret = cpumask_test_cpu(cpu, tick_broadcast_mask);
218 raw_spin_unlock_irqrestore(&tick_broadcast_lock, flags);
222 #ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST
223 int tick_receive_broadcast(void)
225 struct tick_device *td = this_cpu_ptr(&tick_cpu_device);
226 struct clock_event_device *evt = td->evtdev;
231 if (!evt->event_handler)
234 evt->event_handler(evt);
240 * Broadcast the event to the cpus, which are set in the mask (mangled).
242 static void tick_do_broadcast(struct cpumask *mask)
244 int cpu = smp_processor_id();
245 struct tick_device *td;
248 * Check, if the current cpu is in the mask
250 if (cpumask_test_cpu(cpu, mask)) {
251 cpumask_clear_cpu(cpu, mask);
252 td = &per_cpu(tick_cpu_device, cpu);
253 td->evtdev->event_handler(td->evtdev);
256 if (!cpumask_empty(mask)) {
258 * It might be necessary to actually check whether the devices
259 * have different broadcast functions. For now, just use the
260 * one of the first device. This works as long as we have this
261 * misfeature only on x86 (lapic)
263 td = &per_cpu(tick_cpu_device, cpumask_first(mask));
264 td->evtdev->broadcast(mask);
269 * Periodic broadcast:
270 * - invoke the broadcast handlers
272 static void tick_do_periodic_broadcast(void)
274 raw_spin_lock(&tick_broadcast_lock);
276 cpumask_and(tmpmask, cpu_online_mask, tick_broadcast_mask);
277 tick_do_broadcast(tmpmask);
279 raw_spin_unlock(&tick_broadcast_lock);
283 * Event handler for periodic broadcast ticks
285 static void tick_handle_periodic_broadcast(struct clock_event_device *dev)
289 tick_do_periodic_broadcast();
292 * The device is in periodic mode. No reprogramming necessary:
294 if (dev->mode == CLOCK_EVT_MODE_PERIODIC)
298 * Setup the next period for devices, which do not have
299 * periodic mode. We read dev->next_event first and add to it
300 * when the event already expired. clockevents_program_event()
301 * sets dev->next_event only when the event is really
302 * programmed to the device.
304 for (next = dev->next_event; ;) {
305 next = ktime_add(next, tick_period);
307 if (!clockevents_program_event(dev, next, false))
309 tick_do_periodic_broadcast();
314 * Powerstate information: The system enters/leaves a state, where
315 * affected devices might stop
317 static void tick_do_broadcast_on_off(unsigned long *reason)
319 struct clock_event_device *bc, *dev;
320 struct tick_device *td;
324 raw_spin_lock_irqsave(&tick_broadcast_lock, flags);
326 cpu = smp_processor_id();
327 td = &per_cpu(tick_cpu_device, cpu);
329 bc = tick_broadcast_device.evtdev;
332 * Is the device not affected by the powerstate ?
334 if (!dev || !(dev->features & CLOCK_EVT_FEAT_C3STOP))
337 if (!tick_device_is_functional(dev))
340 bc_stopped = cpumask_empty(tick_broadcast_mask);
343 case CLOCK_EVT_NOTIFY_BROADCAST_ON:
344 case CLOCK_EVT_NOTIFY_BROADCAST_FORCE:
345 cpumask_set_cpu(cpu, tick_broadcast_on);
346 if (!cpumask_test_and_set_cpu(cpu, tick_broadcast_mask)) {
347 if (tick_broadcast_device.mode ==
348 TICKDEV_MODE_PERIODIC)
349 clockevents_shutdown(dev);
351 if (*reason == CLOCK_EVT_NOTIFY_BROADCAST_FORCE)
352 tick_broadcast_force = 1;
354 case CLOCK_EVT_NOTIFY_BROADCAST_OFF:
355 if (tick_broadcast_force)
357 cpumask_clear_cpu(cpu, tick_broadcast_on);
358 if (!tick_device_is_functional(dev))
360 if (cpumask_test_and_clear_cpu(cpu, tick_broadcast_mask)) {
361 if (tick_broadcast_device.mode ==
362 TICKDEV_MODE_PERIODIC)
363 tick_setup_periodic(dev, 0);
368 if (cpumask_empty(tick_broadcast_mask)) {
370 clockevents_shutdown(bc);
371 } else if (bc_stopped) {
372 if (tick_broadcast_device.mode == TICKDEV_MODE_PERIODIC)
373 tick_broadcast_start_periodic(bc);
375 tick_broadcast_setup_oneshot(bc);
378 raw_spin_unlock_irqrestore(&tick_broadcast_lock, flags);
382 * Powerstate information: The system enters/leaves a state, where
383 * affected devices might stop.
385 void tick_broadcast_on_off(unsigned long reason, int *oncpu)
387 if (!cpumask_test_cpu(*oncpu, cpu_online_mask))
388 printk(KERN_ERR "tick-broadcast: ignoring broadcast for "
389 "offline CPU #%d\n", *oncpu);
391 tick_do_broadcast_on_off(&reason);
395 * Set the periodic handler depending on broadcast on/off
397 void tick_set_periodic_handler(struct clock_event_device *dev, int broadcast)
400 dev->event_handler = tick_handle_periodic;
402 dev->event_handler = tick_handle_periodic_broadcast;
406 * Remove a CPU from broadcasting
408 void tick_shutdown_broadcast(unsigned int *cpup)
410 struct clock_event_device *bc;
412 unsigned int cpu = *cpup;
414 raw_spin_lock_irqsave(&tick_broadcast_lock, flags);
416 bc = tick_broadcast_device.evtdev;
417 cpumask_clear_cpu(cpu, tick_broadcast_mask);
418 cpumask_clear_cpu(cpu, tick_broadcast_on);
420 if (tick_broadcast_device.mode == TICKDEV_MODE_PERIODIC) {
421 if (bc && cpumask_empty(tick_broadcast_mask))
422 clockevents_shutdown(bc);
425 raw_spin_unlock_irqrestore(&tick_broadcast_lock, flags);
428 void tick_suspend_broadcast(void)
430 struct clock_event_device *bc;
433 raw_spin_lock_irqsave(&tick_broadcast_lock, flags);
435 bc = tick_broadcast_device.evtdev;
437 clockevents_shutdown(bc);
439 raw_spin_unlock_irqrestore(&tick_broadcast_lock, flags);
442 int tick_resume_broadcast(void)
444 struct clock_event_device *bc;
448 raw_spin_lock_irqsave(&tick_broadcast_lock, flags);
450 bc = tick_broadcast_device.evtdev;
453 clockevents_set_mode(bc, CLOCK_EVT_MODE_RESUME);
455 switch (tick_broadcast_device.mode) {
456 case TICKDEV_MODE_PERIODIC:
457 if (!cpumask_empty(tick_broadcast_mask))
458 tick_broadcast_start_periodic(bc);
459 broadcast = cpumask_test_cpu(smp_processor_id(),
460 tick_broadcast_mask);
462 case TICKDEV_MODE_ONESHOT:
463 if (!cpumask_empty(tick_broadcast_mask))
464 broadcast = tick_resume_broadcast_oneshot(bc);
468 raw_spin_unlock_irqrestore(&tick_broadcast_lock, flags);
474 #ifdef CONFIG_TICK_ONESHOT
476 static cpumask_var_t tick_broadcast_oneshot_mask;
477 static cpumask_var_t tick_broadcast_pending_mask;
478 static cpumask_var_t tick_broadcast_force_mask;
481 * Exposed for debugging: see timer_list.c
483 struct cpumask *tick_get_broadcast_oneshot_mask(void)
485 return tick_broadcast_oneshot_mask;
489 * Called before going idle with interrupts disabled. Checks whether a
490 * broadcast event from the other core is about to happen. We detected
491 * that in tick_broadcast_oneshot_control(). The callsite can use this
492 * to avoid a deep idle transition as we are about to get the
493 * broadcast IPI right away.
495 int tick_check_broadcast_expired(void)
497 return cpumask_test_cpu(smp_processor_id(), tick_broadcast_force_mask);
501 * Set broadcast interrupt affinity
503 static void tick_broadcast_set_affinity(struct clock_event_device *bc,
504 const struct cpumask *cpumask)
506 if (!(bc->features & CLOCK_EVT_FEAT_DYNIRQ))
509 if (cpumask_equal(bc->cpumask, cpumask))
512 bc->cpumask = cpumask;
513 irq_set_affinity(bc->irq, bc->cpumask);
516 static int tick_broadcast_set_event(struct clock_event_device *bc, int cpu,
517 ktime_t expires, int force)
521 if (bc->mode != CLOCK_EVT_MODE_ONESHOT)
522 clockevents_set_mode(bc, CLOCK_EVT_MODE_ONESHOT);
524 ret = clockevents_program_event(bc, expires, force);
526 tick_broadcast_set_affinity(bc, cpumask_of(cpu));
530 int tick_resume_broadcast_oneshot(struct clock_event_device *bc)
532 clockevents_set_mode(bc, CLOCK_EVT_MODE_ONESHOT);
537 * Called from irq_enter() when idle was interrupted to reenable the
540 void tick_check_oneshot_broadcast(int cpu)
542 if (cpumask_test_cpu(cpu, tick_broadcast_oneshot_mask)) {
543 struct tick_device *td = &per_cpu(tick_cpu_device, cpu);
546 * We might be in the middle of switching over from
547 * periodic to oneshot. If the CPU has not yet
548 * switched over, leave the device alone.
550 if (td->mode == TICKDEV_MODE_ONESHOT) {
551 clockevents_set_mode(td->evtdev,
552 CLOCK_EVT_MODE_ONESHOT);
558 * Handle oneshot mode broadcasting
560 static void tick_handle_oneshot_broadcast(struct clock_event_device *dev)
562 struct tick_device *td;
563 ktime_t now, next_event;
564 int cpu, next_cpu = 0;
566 raw_spin_lock(&tick_broadcast_lock);
568 dev->next_event.tv64 = KTIME_MAX;
569 next_event.tv64 = KTIME_MAX;
570 cpumask_clear(tmpmask);
572 /* Find all expired events */
573 for_each_cpu(cpu, tick_broadcast_oneshot_mask) {
574 td = &per_cpu(tick_cpu_device, cpu);
575 if (td->evtdev->next_event.tv64 <= now.tv64) {
576 cpumask_set_cpu(cpu, tmpmask);
578 * Mark the remote cpu in the pending mask, so
579 * it can avoid reprogramming the cpu local
580 * timer in tick_broadcast_oneshot_control().
582 cpumask_set_cpu(cpu, tick_broadcast_pending_mask);
583 } else if (td->evtdev->next_event.tv64 < next_event.tv64) {
584 next_event.tv64 = td->evtdev->next_event.tv64;
590 * Remove the current cpu from the pending mask. The event is
591 * delivered immediately in tick_do_broadcast() !
593 cpumask_clear_cpu(smp_processor_id(), tick_broadcast_pending_mask);
595 /* Take care of enforced broadcast requests */
596 cpumask_or(tmpmask, tmpmask, tick_broadcast_force_mask);
597 cpumask_clear(tick_broadcast_force_mask);
600 * Sanity check. Catch the case where we try to broadcast to
603 if (WARN_ON_ONCE(!cpumask_subset(tmpmask, cpu_online_mask)))
604 cpumask_and(tmpmask, tmpmask, cpu_online_mask);
607 * Wakeup the cpus which have an expired event.
609 tick_do_broadcast(tmpmask);
612 * Two reasons for reprogram:
614 * - The global event did not expire any CPU local
615 * events. This happens in dyntick mode, as the maximum PIT
616 * delta is quite small.
618 * - There are pending events on sleeping CPUs which were not
621 if (next_event.tv64 != KTIME_MAX) {
623 * Rearm the broadcast device. If event expired,
626 if (tick_broadcast_set_event(dev, next_cpu, next_event, 0))
629 raw_spin_unlock(&tick_broadcast_lock);
633 * Powerstate information: The system enters/leaves a state, where
634 * affected devices might stop
636 void tick_broadcast_oneshot_control(unsigned long reason)
638 struct clock_event_device *bc, *dev;
639 struct tick_device *td;
645 * Periodic mode does not care about the enter/exit of power
648 if (tick_broadcast_device.mode == TICKDEV_MODE_PERIODIC)
652 * We are called with preemtion disabled from the depth of the
653 * idle code, so we can't be moved away.
655 cpu = smp_processor_id();
656 td = &per_cpu(tick_cpu_device, cpu);
659 if (!(dev->features & CLOCK_EVT_FEAT_C3STOP))
662 bc = tick_broadcast_device.evtdev;
664 raw_spin_lock_irqsave(&tick_broadcast_lock, flags);
665 if (reason == CLOCK_EVT_NOTIFY_BROADCAST_ENTER) {
666 if (!cpumask_test_and_set_cpu(cpu, tick_broadcast_oneshot_mask)) {
667 WARN_ON_ONCE(cpumask_test_cpu(cpu, tick_broadcast_pending_mask));
668 clockevents_set_mode(dev, CLOCK_EVT_MODE_SHUTDOWN);
670 * We only reprogram the broadcast timer if we
671 * did not mark ourself in the force mask and
672 * if the cpu local event is earlier than the
673 * broadcast event. If the current CPU is in
674 * the force mask, then we are going to be
675 * woken by the IPI right away.
677 if (!cpumask_test_cpu(cpu, tick_broadcast_force_mask) &&
678 dev->next_event.tv64 < bc->next_event.tv64)
679 tick_broadcast_set_event(bc, cpu, dev->next_event, 1);
682 if (cpumask_test_and_clear_cpu(cpu, tick_broadcast_oneshot_mask)) {
683 clockevents_set_mode(dev, CLOCK_EVT_MODE_ONESHOT);
685 * The cpu which was handling the broadcast
686 * timer marked this cpu in the broadcast
687 * pending mask and fired the broadcast
688 * IPI. So we are going to handle the expired
689 * event anyway via the broadcast IPI
690 * handler. No need to reprogram the timer
691 * with an already expired event.
693 if (cpumask_test_and_clear_cpu(cpu,
694 tick_broadcast_pending_mask))
698 * Bail out if there is no next event.
700 if (dev->next_event.tv64 == KTIME_MAX)
703 * If the pending bit is not set, then we are
704 * either the CPU handling the broadcast
705 * interrupt or we got woken by something else.
707 * We are not longer in the broadcast mask, so
708 * if the cpu local expiry time is already
709 * reached, we would reprogram the cpu local
710 * timer with an already expired event.
712 * This can lead to a ping-pong when we return
713 * to idle and therefor rearm the broadcast
714 * timer before the cpu local timer was able
715 * to fire. This happens because the forced
716 * reprogramming makes sure that the event
717 * will happen in the future and depending on
718 * the min_delta setting this might be far
719 * enough out that the ping-pong starts.
721 * If the cpu local next_event has expired
722 * then we know that the broadcast timer
723 * next_event has expired as well and
724 * broadcast is about to be handled. So we
725 * avoid reprogramming and enforce that the
726 * broadcast handler, which did not run yet,
727 * will invoke the cpu local handler.
729 * We cannot call the handler directly from
730 * here, because we might be in a NOHZ phase
731 * and we did not go through the irq_enter()
735 if (dev->next_event.tv64 <= now.tv64) {
736 cpumask_set_cpu(cpu, tick_broadcast_force_mask);
740 * We got woken by something else. Reprogram
741 * the cpu local timer device.
743 tick_program_event(dev->next_event, 1);
747 raw_spin_unlock_irqrestore(&tick_broadcast_lock, flags);
751 * Reset the one shot broadcast for a cpu
753 * Called with tick_broadcast_lock held
755 static void tick_broadcast_clear_oneshot(int cpu)
757 cpumask_clear_cpu(cpu, tick_broadcast_oneshot_mask);
760 static void tick_broadcast_init_next_event(struct cpumask *mask,
763 struct tick_device *td;
766 for_each_cpu(cpu, mask) {
767 td = &per_cpu(tick_cpu_device, cpu);
769 td->evtdev->next_event = expires;
774 * tick_broadcast_setup_oneshot - setup the broadcast device
776 void tick_broadcast_setup_oneshot(struct clock_event_device *bc)
778 int cpu = smp_processor_id();
780 /* Set it up only once ! */
781 if (bc->event_handler != tick_handle_oneshot_broadcast) {
782 int was_periodic = bc->mode == CLOCK_EVT_MODE_PERIODIC;
784 bc->event_handler = tick_handle_oneshot_broadcast;
787 * We must be careful here. There might be other CPUs
788 * waiting for periodic broadcast. We need to set the
789 * oneshot_mask bits for those and program the
790 * broadcast device to fire.
792 cpumask_copy(tmpmask, tick_broadcast_mask);
793 cpumask_clear_cpu(cpu, tmpmask);
794 cpumask_or(tick_broadcast_oneshot_mask,
795 tick_broadcast_oneshot_mask, tmpmask);
797 if (was_periodic && !cpumask_empty(tmpmask)) {
798 clockevents_set_mode(bc, CLOCK_EVT_MODE_ONESHOT);
799 tick_broadcast_init_next_event(tmpmask,
801 tick_broadcast_set_event(bc, cpu, tick_next_period, 1);
803 bc->next_event.tv64 = KTIME_MAX;
806 * The first cpu which switches to oneshot mode sets
807 * the bit for all other cpus which are in the general
808 * (periodic) broadcast mask. So the bit is set and
809 * would prevent the first broadcast enter after this
810 * to program the bc device.
812 tick_broadcast_clear_oneshot(cpu);
817 * Select oneshot operating mode for the broadcast device
819 void tick_broadcast_switch_to_oneshot(void)
821 struct clock_event_device *bc;
824 raw_spin_lock_irqsave(&tick_broadcast_lock, flags);
826 tick_broadcast_device.mode = TICKDEV_MODE_ONESHOT;
827 bc = tick_broadcast_device.evtdev;
829 tick_broadcast_setup_oneshot(bc);
831 raw_spin_unlock_irqrestore(&tick_broadcast_lock, flags);
836 * Remove a dead CPU from broadcasting
838 void tick_shutdown_broadcast_oneshot(unsigned int *cpup)
841 unsigned int cpu = *cpup;
843 raw_spin_lock_irqsave(&tick_broadcast_lock, flags);
846 * Clear the broadcast masks for the dead cpu, but do not stop
847 * the broadcast device!
849 cpumask_clear_cpu(cpu, tick_broadcast_oneshot_mask);
850 cpumask_clear_cpu(cpu, tick_broadcast_pending_mask);
851 cpumask_clear_cpu(cpu, tick_broadcast_force_mask);
853 raw_spin_unlock_irqrestore(&tick_broadcast_lock, flags);
857 * Check, whether the broadcast device is in one shot mode
859 int tick_broadcast_oneshot_active(void)
861 return tick_broadcast_device.mode == TICKDEV_MODE_ONESHOT;
865 * Check whether the broadcast device supports oneshot.
867 bool tick_broadcast_oneshot_available(void)
869 struct clock_event_device *bc = tick_broadcast_device.evtdev;
871 return bc ? bc->features & CLOCK_EVT_FEAT_ONESHOT : false;
876 void __init tick_broadcast_init(void)
878 zalloc_cpumask_var(&tick_broadcast_mask, GFP_NOWAIT);
879 zalloc_cpumask_var(&tick_broadcast_on, GFP_NOWAIT);
880 zalloc_cpumask_var(&tmpmask, GFP_NOWAIT);
881 #ifdef CONFIG_TICK_ONESHOT
882 zalloc_cpumask_var(&tick_broadcast_oneshot_mask, GFP_NOWAIT);
883 zalloc_cpumask_var(&tick_broadcast_pending_mask, GFP_NOWAIT);
884 zalloc_cpumask_var(&tick_broadcast_force_mask, GFP_NOWAIT);