]>
Commit | Line | Data |
---|---|---|
906568c9 TG |
1 | /* |
2 | * linux/kernel/time/tick-common.c | |
3 | * | |
4 | * This file contains the base functions to manage periodic tick | |
5 | * related events. | |
6 | * | |
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 | |
10 | * | |
11 | * This code is licenced under the GPL version 2. For details see | |
12 | * kernel-base/COPYING. | |
13 | */ | |
14 | #include <linux/cpu.h> | |
15 | #include <linux/err.h> | |
16 | #include <linux/hrtimer.h> | |
d7b90689 | 17 | #include <linux/interrupt.h> |
906568c9 TG |
18 | #include <linux/percpu.h> |
19 | #include <linux/profile.h> | |
20 | #include <linux/sched.h> | |
ccf33d68 | 21 | #include <linux/module.h> |
75e0678e | 22 | #include <trace/events/power.h> |
906568c9 | 23 | |
d7b90689 RK |
24 | #include <asm/irq_regs.h> |
25 | ||
f8381cba TG |
26 | #include "tick-internal.h" |
27 | ||
906568c9 TG |
28 | /* |
29 | * Tick devices | |
30 | */ | |
f8381cba | 31 | DEFINE_PER_CPU(struct tick_device, tick_cpu_device); |
906568c9 TG |
32 | /* |
33 | * Tick next event: keeps track of the tick time | |
34 | */ | |
f8381cba TG |
35 | ktime_t tick_next_period; |
36 | ktime_t tick_period; | |
050ded1b AM |
37 | |
38 | /* | |
39 | * tick_do_timer_cpu is a timer core internal variable which holds the CPU NR | |
40 | * which is responsible for calling do_timer(), i.e. the timekeeping stuff. This | |
41 | * variable has two functions: | |
42 | * | |
43 | * 1) Prevent a thundering herd issue of a gazillion of CPUs trying to grab the | |
44 | * timekeeping lock all at once. Only the CPU which is assigned to do the | |
45 | * update is handling it. | |
46 | * | |
47 | * 2) Hand off the duty in the NOHZ idle case by setting the value to | |
48 | * TICK_DO_TIMER_NONE, i.e. a non existing CPU. So the next cpu which looks | |
49 | * at it will take over and keep the time keeping alive. The handover | |
50 | * procedure also covers cpu hotplug. | |
51 | */ | |
6441402b | 52 | int tick_do_timer_cpu __read_mostly = TICK_DO_TIMER_BOOT; |
906568c9 | 53 | |
289f480a IM |
54 | /* |
55 | * Debugging: see timer_list.c | |
56 | */ | |
57 | struct tick_device *tick_get_device(int cpu) | |
58 | { | |
59 | return &per_cpu(tick_cpu_device, cpu); | |
60 | } | |
61 | ||
79bf2bb3 TG |
62 | /** |
63 | * tick_is_oneshot_available - check for a oneshot capable event device | |
64 | */ | |
65 | int tick_is_oneshot_available(void) | |
66 | { | |
909ea964 | 67 | struct clock_event_device *dev = __this_cpu_read(tick_cpu_device.evtdev); |
79bf2bb3 | 68 | |
3a142a06 TG |
69 | if (!dev || !(dev->features & CLOCK_EVT_FEAT_ONESHOT)) |
70 | return 0; | |
71 | if (!(dev->features & CLOCK_EVT_FEAT_C3STOP)) | |
72 | return 1; | |
73 | return tick_broadcast_oneshot_available(); | |
79bf2bb3 TG |
74 | } |
75 | ||
906568c9 TG |
76 | /* |
77 | * Periodic tick | |
78 | */ | |
79 | static void tick_periodic(int cpu) | |
80 | { | |
81 | if (tick_do_timer_cpu == cpu) { | |
d6ad4187 | 82 | write_seqlock(&jiffies_lock); |
906568c9 TG |
83 | |
84 | /* Keep track of the next tick event */ | |
85 | tick_next_period = ktime_add(tick_next_period, tick_period); | |
86 | ||
87 | do_timer(1); | |
d6ad4187 | 88 | write_sequnlock(&jiffies_lock); |
47a1b796 | 89 | update_wall_time(); |
906568c9 TG |
90 | } |
91 | ||
92 | update_process_times(user_mode(get_irq_regs())); | |
93 | profile_tick(CPU_PROFILING); | |
94 | } | |
95 | ||
96 | /* | |
97 | * Event handler for periodic ticks | |
98 | */ | |
99 | void tick_handle_periodic(struct clock_event_device *dev) | |
100 | { | |
101 | int cpu = smp_processor_id(); | |
b97f0291 | 102 | ktime_t next = dev->next_event; |
906568c9 TG |
103 | |
104 | tick_periodic(cpu); | |
105 | ||
c6eb3f70 TG |
106 | #if defined(CONFIG_HIGH_RES_TIMERS) || defined(CONFIG_NO_HZ_COMMON) |
107 | /* | |
108 | * The cpu might have transitioned to HIGHRES or NOHZ mode via | |
109 | * update_process_times() -> run_local_timers() -> | |
110 | * hrtimer_run_queues(). | |
111 | */ | |
112 | if (dev->event_handler != tick_handle_periodic) | |
113 | return; | |
114 | #endif | |
115 | ||
472c4a94 | 116 | if (!clockevent_state_oneshot(dev)) |
906568c9 | 117 | return; |
906568c9 | 118 | for (;;) { |
b97f0291 VK |
119 | /* |
120 | * Setup the next period for devices, which do not have | |
121 | * periodic mode: | |
122 | */ | |
123 | next = ktime_add(next, tick_period); | |
124 | ||
d1748302 | 125 | if (!clockevents_program_event(dev, next, false)) |
906568c9 | 126 | return; |
74a03b69 JS |
127 | /* |
128 | * Have to be careful here. If we're in oneshot mode, | |
129 | * before we call tick_periodic() in a loop, we need | |
130 | * to be sure we're using a real hardware clocksource. | |
131 | * Otherwise we could get trapped in an infinite | |
132 | * loop, as the tick_periodic() increments jiffies, | |
cacb3c76 | 133 | * which then will increment time, possibly causing |
74a03b69 JS |
134 | * the loop to trigger again and again. |
135 | */ | |
136 | if (timekeeping_valid_for_hres()) | |
137 | tick_periodic(cpu); | |
906568c9 TG |
138 | } |
139 | } | |
140 | ||
141 | /* | |
142 | * Setup the device for a periodic tick | |
143 | */ | |
f8381cba | 144 | void tick_setup_periodic(struct clock_event_device *dev, int broadcast) |
906568c9 | 145 | { |
f8381cba TG |
146 | tick_set_periodic_handler(dev, broadcast); |
147 | ||
148 | /* Broadcast setup ? */ | |
149 | if (!tick_device_is_functional(dev)) | |
150 | return; | |
906568c9 | 151 | |
27ce4cb4 TG |
152 | if ((dev->features & CLOCK_EVT_FEAT_PERIODIC) && |
153 | !tick_broadcast_oneshot_active()) { | |
d7eb231c | 154 | clockevents_switch_state(dev, CLOCK_EVT_STATE_PERIODIC); |
906568c9 TG |
155 | } else { |
156 | unsigned long seq; | |
157 | ktime_t next; | |
158 | ||
159 | do { | |
d6ad4187 | 160 | seq = read_seqbegin(&jiffies_lock); |
906568c9 | 161 | next = tick_next_period; |
d6ad4187 | 162 | } while (read_seqretry(&jiffies_lock, seq)); |
906568c9 | 163 | |
d7eb231c | 164 | clockevents_switch_state(dev, CLOCK_EVT_STATE_ONESHOT); |
906568c9 TG |
165 | |
166 | for (;;) { | |
d1748302 | 167 | if (!clockevents_program_event(dev, next, false)) |
906568c9 TG |
168 | return; |
169 | next = ktime_add(next, tick_period); | |
170 | } | |
171 | } | |
172 | } | |
173 | ||
174 | /* | |
175 | * Setup the tick device | |
176 | */ | |
177 | static void tick_setup_device(struct tick_device *td, | |
178 | struct clock_event_device *newdev, int cpu, | |
0de26520 | 179 | const struct cpumask *cpumask) |
906568c9 TG |
180 | { |
181 | ktime_t next_event; | |
182 | void (*handler)(struct clock_event_device *) = NULL; | |
183 | ||
184 | /* | |
185 | * First device setup ? | |
186 | */ | |
187 | if (!td->evtdev) { | |
188 | /* | |
189 | * If no cpu took the do_timer update, assign it to | |
190 | * this cpu: | |
191 | */ | |
6441402b | 192 | if (tick_do_timer_cpu == TICK_DO_TIMER_BOOT) { |
c5bfece2 | 193 | if (!tick_nohz_full_cpu(cpu)) |
a382bf93 FW |
194 | tick_do_timer_cpu = cpu; |
195 | else | |
196 | tick_do_timer_cpu = TICK_DO_TIMER_NONE; | |
906568c9 TG |
197 | tick_next_period = ktime_get(); |
198 | tick_period = ktime_set(0, NSEC_PER_SEC / HZ); | |
199 | } | |
200 | ||
201 | /* | |
202 | * Startup in periodic mode first. | |
203 | */ | |
204 | td->mode = TICKDEV_MODE_PERIODIC; | |
205 | } else { | |
206 | handler = td->evtdev->event_handler; | |
207 | next_event = td->evtdev->next_event; | |
7c1e7689 | 208 | td->evtdev->event_handler = clockevents_handle_noop; |
906568c9 TG |
209 | } |
210 | ||
211 | td->evtdev = newdev; | |
212 | ||
213 | /* | |
214 | * When the device is not per cpu, pin the interrupt to the | |
215 | * current cpu: | |
216 | */ | |
320ab2b0 | 217 | if (!cpumask_equal(newdev->cpumask, cpumask)) |
0de26520 | 218 | irq_set_affinity(newdev->irq, cpumask); |
906568c9 | 219 | |
f8381cba TG |
220 | /* |
221 | * When global broadcasting is active, check if the current | |
222 | * device is registered as a placeholder for broadcast mode. | |
223 | * This allows us to handle this x86 misfeature in a generic | |
07bd1172 TG |
224 | * way. This function also returns !=0 when we keep the |
225 | * current active broadcast state for this CPU. | |
f8381cba TG |
226 | */ |
227 | if (tick_device_uses_broadcast(newdev, cpu)) | |
228 | return; | |
229 | ||
906568c9 TG |
230 | if (td->mode == TICKDEV_MODE_PERIODIC) |
231 | tick_setup_periodic(newdev, 0); | |
79bf2bb3 TG |
232 | else |
233 | tick_setup_oneshot(newdev, handler, next_event); | |
906568c9 TG |
234 | } |
235 | ||
03e13cf5 TG |
236 | void tick_install_replacement(struct clock_event_device *newdev) |
237 | { | |
22127e93 | 238 | struct tick_device *td = this_cpu_ptr(&tick_cpu_device); |
03e13cf5 TG |
239 | int cpu = smp_processor_id(); |
240 | ||
241 | clockevents_exchange_device(td->evtdev, newdev); | |
242 | tick_setup_device(td, newdev, cpu, cpumask_of(cpu)); | |
243 | if (newdev->features & CLOCK_EVT_FEAT_ONESHOT) | |
244 | tick_oneshot_notify(); | |
245 | } | |
246 | ||
45cb8e01 TG |
247 | static bool tick_check_percpu(struct clock_event_device *curdev, |
248 | struct clock_event_device *newdev, int cpu) | |
249 | { | |
250 | if (!cpumask_test_cpu(cpu, newdev->cpumask)) | |
251 | return false; | |
252 | if (cpumask_equal(newdev->cpumask, cpumask_of(cpu))) | |
253 | return true; | |
254 | /* Check if irq affinity can be set */ | |
255 | if (newdev->irq >= 0 && !irq_can_set_affinity(newdev->irq)) | |
256 | return false; | |
257 | /* Prefer an existing cpu local device */ | |
258 | if (curdev && cpumask_equal(curdev->cpumask, cpumask_of(cpu))) | |
259 | return false; | |
260 | return true; | |
261 | } | |
262 | ||
263 | static bool tick_check_preferred(struct clock_event_device *curdev, | |
264 | struct clock_event_device *newdev) | |
265 | { | |
266 | /* Prefer oneshot capable device */ | |
267 | if (!(newdev->features & CLOCK_EVT_FEAT_ONESHOT)) { | |
268 | if (curdev && (curdev->features & CLOCK_EVT_FEAT_ONESHOT)) | |
269 | return false; | |
270 | if (tick_oneshot_mode_active()) | |
271 | return false; | |
272 | } | |
273 | ||
70e5975d SB |
274 | /* |
275 | * Use the higher rated one, but prefer a CPU local device with a lower | |
276 | * rating than a non-CPU local device | |
277 | */ | |
278 | return !curdev || | |
279 | newdev->rating > curdev->rating || | |
280 | !cpumask_equal(curdev->cpumask, newdev->cpumask); | |
45cb8e01 TG |
281 | } |
282 | ||
03e13cf5 TG |
283 | /* |
284 | * Check whether the new device is a better fit than curdev. curdev | |
285 | * can be NULL ! | |
286 | */ | |
287 | bool tick_check_replacement(struct clock_event_device *curdev, | |
288 | struct clock_event_device *newdev) | |
289 | { | |
521c4299 | 290 | if (!tick_check_percpu(curdev, newdev, smp_processor_id())) |
03e13cf5 TG |
291 | return false; |
292 | ||
293 | return tick_check_preferred(curdev, newdev); | |
294 | } | |
295 | ||
906568c9 | 296 | /* |
7126cac4 TG |
297 | * Check, if the new registered device should be used. Called with |
298 | * clockevents_lock held and interrupts disabled. | |
906568c9 | 299 | */ |
7172a286 | 300 | void tick_check_new_device(struct clock_event_device *newdev) |
906568c9 TG |
301 | { |
302 | struct clock_event_device *curdev; | |
303 | struct tick_device *td; | |
7172a286 | 304 | int cpu; |
906568c9 TG |
305 | |
306 | cpu = smp_processor_id(); | |
320ab2b0 | 307 | if (!cpumask_test_cpu(cpu, newdev->cpumask)) |
4a93232d | 308 | goto out_bc; |
906568c9 TG |
309 | |
310 | td = &per_cpu(tick_cpu_device, cpu); | |
311 | curdev = td->evtdev; | |
906568c9 TG |
312 | |
313 | /* cpu local device ? */ | |
45cb8e01 TG |
314 | if (!tick_check_percpu(curdev, newdev, cpu)) |
315 | goto out_bc; | |
906568c9 | 316 | |
45cb8e01 TG |
317 | /* Preference decision */ |
318 | if (!tick_check_preferred(curdev, newdev)) | |
319 | goto out_bc; | |
906568c9 | 320 | |
ccf33d68 TG |
321 | if (!try_module_get(newdev->owner)) |
322 | return; | |
323 | ||
906568c9 TG |
324 | /* |
325 | * Replace the eventually existing device by the new | |
f8381cba TG |
326 | * device. If the current device is the broadcast device, do |
327 | * not give it back to the clockevents layer ! | |
906568c9 | 328 | */ |
f8381cba | 329 | if (tick_is_broadcast_device(curdev)) { |
2344abbc | 330 | clockevents_shutdown(curdev); |
f8381cba TG |
331 | curdev = NULL; |
332 | } | |
906568c9 | 333 | clockevents_exchange_device(curdev, newdev); |
6b954823 | 334 | tick_setup_device(td, newdev, cpu, cpumask_of(cpu)); |
79bf2bb3 TG |
335 | if (newdev->features & CLOCK_EVT_FEAT_ONESHOT) |
336 | tick_oneshot_notify(); | |
7172a286 | 337 | return; |
f8381cba TG |
338 | |
339 | out_bc: | |
340 | /* | |
341 | * Can the new device be used as a broadcast device ? | |
342 | */ | |
7172a286 | 343 | tick_install_broadcast_device(newdev); |
906568c9 TG |
344 | } |
345 | ||
f32dd117 TG |
346 | /** |
347 | * tick_broadcast_oneshot_control - Enter/exit broadcast oneshot mode | |
348 | * @state: The target state (enter/exit) | |
349 | * | |
350 | * The system enters/leaves a state, where affected devices might stop | |
351 | * Returns 0 on success, -EBUSY if the cpu is used to broadcast wakeups. | |
352 | * | |
353 | * Called with interrupts disabled, so clockevents_lock is not | |
354 | * required here because the local clock event device cannot go away | |
355 | * under us. | |
356 | */ | |
357 | int tick_broadcast_oneshot_control(enum tick_broadcast_state state) | |
358 | { | |
359 | struct tick_device *td = this_cpu_ptr(&tick_cpu_device); | |
360 | ||
361 | if (!(td->evtdev->features & CLOCK_EVT_FEAT_C3STOP)) | |
362 | return 0; | |
363 | ||
364 | return __tick_broadcast_oneshot_control(state); | |
365 | } | |
0f447051 | 366 | EXPORT_SYMBOL_GPL(tick_broadcast_oneshot_control); |
f32dd117 | 367 | |
52c063d1 | 368 | #ifdef CONFIG_HOTPLUG_CPU |
94df7de0 SD |
369 | /* |
370 | * Transfer the do_timer job away from a dying cpu. | |
371 | * | |
52c063d1 TG |
372 | * Called with interrupts disabled. Not locking required. If |
373 | * tick_do_timer_cpu is owned by this cpu, nothing can change it. | |
94df7de0 | 374 | */ |
52c063d1 | 375 | void tick_handover_do_timer(void) |
94df7de0 | 376 | { |
52c063d1 | 377 | if (tick_do_timer_cpu == smp_processor_id()) { |
94df7de0 SD |
378 | int cpu = cpumask_first(cpu_online_mask); |
379 | ||
380 | tick_do_timer_cpu = (cpu < nr_cpu_ids) ? cpu : | |
381 | TICK_DO_TIMER_NONE; | |
382 | } | |
383 | } | |
384 | ||
906568c9 TG |
385 | /* |
386 | * Shutdown an event device on a given cpu: | |
387 | * | |
388 | * This is called on a life CPU, when a CPU is dead. So we cannot | |
389 | * access the hardware device itself. | |
390 | * We just set the mode and remove it from the lists. | |
391 | */ | |
a49b116d | 392 | void tick_shutdown(unsigned int cpu) |
906568c9 | 393 | { |
a49b116d | 394 | struct tick_device *td = &per_cpu(tick_cpu_device, cpu); |
906568c9 | 395 | struct clock_event_device *dev = td->evtdev; |
906568c9 | 396 | |
906568c9 TG |
397 | td->mode = TICKDEV_MODE_PERIODIC; |
398 | if (dev) { | |
399 | /* | |
400 | * Prevent that the clock events layer tries to call | |
401 | * the set mode function! | |
402 | */ | |
051ebd10 | 403 | clockevent_set_state(dev, CLOCK_EVT_STATE_DETACHED); |
906568c9 TG |
404 | dev->mode = CLOCK_EVT_MODE_UNUSED; |
405 | clockevents_exchange_device(dev, NULL); | |
6f7a05d7 | 406 | dev->event_handler = clockevents_handle_noop; |
906568c9 TG |
407 | td->evtdev = NULL; |
408 | } | |
906568c9 | 409 | } |
a49b116d | 410 | #endif |
906568c9 | 411 | |
4ffee521 | 412 | /** |
f46481d0 | 413 | * tick_suspend_local - Suspend the local tick device |
4ffee521 | 414 | * |
f46481d0 | 415 | * Called from the local cpu for freeze with interrupts disabled. |
4ffee521 TG |
416 | * |
417 | * No locks required. Nothing can change the per cpu device. | |
418 | */ | |
7270d11c | 419 | void tick_suspend_local(void) |
6321dd60 | 420 | { |
22127e93 | 421 | struct tick_device *td = this_cpu_ptr(&tick_cpu_device); |
6321dd60 | 422 | |
2344abbc | 423 | clockevents_shutdown(td->evtdev); |
6321dd60 TG |
424 | } |
425 | ||
4ffee521 | 426 | /** |
f46481d0 | 427 | * tick_resume_local - Resume the local tick device |
4ffee521 | 428 | * |
f46481d0 | 429 | * Called from the local CPU for unfreeze or XEN resume magic. |
4ffee521 TG |
430 | * |
431 | * No locks required. Nothing can change the per cpu device. | |
432 | */ | |
f46481d0 | 433 | void tick_resume_local(void) |
6321dd60 | 434 | { |
f46481d0 TG |
435 | struct tick_device *td = this_cpu_ptr(&tick_cpu_device); |
436 | bool broadcast = tick_resume_check_broadcast(); | |
6321dd60 | 437 | |
554ef387 | 438 | clockevents_tick_resume(td->evtdev); |
18de5bc4 TG |
439 | if (!broadcast) { |
440 | if (td->mode == TICKDEV_MODE_PERIODIC) | |
441 | tick_setup_periodic(td->evtdev, 0); | |
442 | else | |
443 | tick_resume_oneshot(); | |
444 | } | |
6321dd60 TG |
445 | } |
446 | ||
f46481d0 TG |
447 | /** |
448 | * tick_suspend - Suspend the tick and the broadcast device | |
449 | * | |
450 | * Called from syscore_suspend() via timekeeping_suspend with only one | |
451 | * CPU online and interrupts disabled or from tick_unfreeze() under | |
452 | * tick_freeze_lock. | |
453 | * | |
454 | * No locks required. Nothing can change the per cpu device. | |
455 | */ | |
456 | void tick_suspend(void) | |
457 | { | |
458 | tick_suspend_local(); | |
459 | tick_suspend_broadcast(); | |
460 | } | |
461 | ||
462 | /** | |
463 | * tick_resume - Resume the tick and the broadcast device | |
464 | * | |
465 | * Called from syscore_resume() via timekeeping_resume with only one | |
466 | * CPU online and interrupts disabled. | |
467 | * | |
468 | * No locks required. Nothing can change the per cpu device. | |
469 | */ | |
470 | void tick_resume(void) | |
471 | { | |
472 | tick_resume_broadcast(); | |
473 | tick_resume_local(); | |
474 | } | |
475 | ||
87e9b9f1 | 476 | #ifdef CONFIG_SUSPEND |
124cf911 RW |
477 | static DEFINE_RAW_SPINLOCK(tick_freeze_lock); |
478 | static unsigned int tick_freeze_depth; | |
479 | ||
480 | /** | |
481 | * tick_freeze - Suspend the local tick and (possibly) timekeeping. | |
482 | * | |
483 | * Check if this is the last online CPU executing the function and if so, | |
484 | * suspend timekeeping. Otherwise suspend the local tick. | |
485 | * | |
486 | * Call with interrupts disabled. Must be balanced with %tick_unfreeze(). | |
487 | * Interrupts must not be enabled before the subsequent %tick_unfreeze(). | |
488 | */ | |
489 | void tick_freeze(void) | |
490 | { | |
491 | raw_spin_lock(&tick_freeze_lock); | |
492 | ||
493 | tick_freeze_depth++; | |
75e0678e RW |
494 | if (tick_freeze_depth == num_online_cpus()) { |
495 | trace_suspend_resume(TPS("timekeeping_freeze"), | |
496 | smp_processor_id(), true); | |
124cf911 | 497 | timekeeping_suspend(); |
75e0678e | 498 | } else { |
f46481d0 | 499 | tick_suspend_local(); |
75e0678e | 500 | } |
124cf911 RW |
501 | |
502 | raw_spin_unlock(&tick_freeze_lock); | |
503 | } | |
504 | ||
505 | /** | |
506 | * tick_unfreeze - Resume the local tick and (possibly) timekeeping. | |
507 | * | |
508 | * Check if this is the first CPU executing the function and if so, resume | |
509 | * timekeeping. Otherwise resume the local tick. | |
510 | * | |
511 | * Call with interrupts disabled. Must be balanced with %tick_freeze(). | |
512 | * Interrupts must not be enabled after the preceding %tick_freeze(). | |
513 | */ | |
514 | void tick_unfreeze(void) | |
515 | { | |
516 | raw_spin_lock(&tick_freeze_lock); | |
517 | ||
75e0678e | 518 | if (tick_freeze_depth == num_online_cpus()) { |
124cf911 | 519 | timekeeping_resume(); |
75e0678e RW |
520 | trace_suspend_resume(TPS("timekeeping_freeze"), |
521 | smp_processor_id(), false); | |
522 | } else { | |
422fe750 | 523 | tick_resume_local(); |
75e0678e | 524 | } |
124cf911 RW |
525 | |
526 | tick_freeze_depth--; | |
527 | ||
528 | raw_spin_unlock(&tick_freeze_lock); | |
529 | } | |
87e9b9f1 | 530 | #endif /* CONFIG_SUSPEND */ |
124cf911 | 531 | |
906568c9 TG |
532 | /** |
533 | * tick_init - initialize the tick control | |
906568c9 TG |
534 | */ |
535 | void __init tick_init(void) | |
536 | { | |
b352bc1c | 537 | tick_broadcast_init(); |
a80e49e2 | 538 | tick_nohz_init(); |
906568c9 | 539 | } |