4 * Kernel internal timers, basic process system calls
6 * Copyright (C) 1991, 1992 Linus Torvalds
8 * 1997-01-28 Modified by Finn Arne Gangstad to make timers scale better.
10 * 1997-09-10 Updated NTP code according to technical memorandum Jan '96
11 * "A Kernel Model for Precision Timekeeping" by Dave Mills
12 * 1998-12-24 Fixed a xtime SMP race (we need the xtime_lock rw spinlock to
13 * serialize accesses to xtime/lost_ticks).
14 * Copyright (C) 1998 Andrea Arcangeli
15 * 1999-03-10 Improved NTP compatibility by Ulrich Windl
16 * 2002-05-31 Move sys_sysinfo here and make its locking sane, Robert Love
17 * 2000-10-05 Implemented scalable SMP per-CPU timer handling.
18 * Copyright (C) 2000, 2001, 2002 Ingo Molnar
19 * Designed by David S. Miller, Alexey Kuznetsov and Ingo Molnar
22 #include <linux/kernel_stat.h>
23 #include <linux/module.h>
24 #include <linux/interrupt.h>
25 #include <linux/percpu.h>
26 #include <linux/init.h>
28 #include <linux/swap.h>
29 #include <linux/pid_namespace.h>
30 #include <linux/notifier.h>
31 #include <linux/thread_info.h>
32 #include <linux/time.h>
33 #include <linux/jiffies.h>
34 #include <linux/posix-timers.h>
35 #include <linux/cpu.h>
36 #include <linux/syscalls.h>
37 #include <linux/delay.h>
38 #include <linux/tick.h>
39 #include <linux/kallsyms.h>
40 #include <linux/perf_event.h>
41 #include <linux/sched.h>
43 #include <asm/uaccess.h>
44 #include <asm/unistd.h>
45 #include <asm/div64.h>
46 #include <asm/timex.h>
49 #define CREATE_TRACE_POINTS
50 #include <trace/events/timer.h>
52 u64 jiffies_64 __cacheline_aligned_in_smp
= INITIAL_JIFFIES
;
54 EXPORT_SYMBOL(jiffies_64
);
57 * per-CPU timer vector definitions:
59 #define TVN_BITS (CONFIG_BASE_SMALL ? 4 : 6)
60 #define TVR_BITS (CONFIG_BASE_SMALL ? 6 : 8)
61 #define TVN_SIZE (1 << TVN_BITS)
62 #define TVR_SIZE (1 << TVR_BITS)
63 #define TVN_MASK (TVN_SIZE - 1)
64 #define TVR_MASK (TVR_SIZE - 1)
67 struct list_head vec
[TVN_SIZE
];
71 struct list_head vec
[TVR_SIZE
];
76 struct timer_list
*running_timer
;
77 unsigned long timer_jiffies
;
78 unsigned long next_timer
;
84 } ____cacheline_aligned
;
86 struct tvec_base boot_tvec_bases
;
87 EXPORT_SYMBOL(boot_tvec_bases
);
88 static DEFINE_PER_CPU(struct tvec_base
*, tvec_bases
) = &boot_tvec_bases
;
91 * Note that all tvec_bases are 2 byte aligned and lower bit of
92 * base in timer_list is guaranteed to be zero. Use the LSB for
93 * the new flag to indicate whether the timer is deferrable
95 #define TBASE_DEFERRABLE_FLAG (0x1)
97 /* Functions below help us manage 'deferrable' flag */
98 static inline unsigned int tbase_get_deferrable(struct tvec_base
*base
)
100 return ((unsigned int)(unsigned long)base
& TBASE_DEFERRABLE_FLAG
);
103 static inline struct tvec_base
*tbase_get_base(struct tvec_base
*base
)
105 return ((struct tvec_base
*)((unsigned long)base
& ~TBASE_DEFERRABLE_FLAG
));
108 static inline void timer_set_deferrable(struct timer_list
*timer
)
110 timer
->base
= ((struct tvec_base
*)((unsigned long)(timer
->base
) |
111 TBASE_DEFERRABLE_FLAG
));
115 timer_set_base(struct timer_list
*timer
, struct tvec_base
*new_base
)
117 timer
->base
= (struct tvec_base
*)((unsigned long)(new_base
) |
118 tbase_get_deferrable(timer
->base
));
121 static unsigned long round_jiffies_common(unsigned long j
, int cpu
,
125 unsigned long original
= j
;
128 * We don't want all cpus firing their timers at once hitting the
129 * same lock or cachelines, so we skew each extra cpu with an extra
130 * 3 jiffies. This 3 jiffies came originally from the mm/ code which
132 * The skew is done by adding 3*cpunr, then round, then subtract this
133 * extra offset again.
140 * If the target jiffie is just after a whole second (which can happen
141 * due to delays of the timer irq, long irq off times etc etc) then
142 * we should round down to the whole second, not up. Use 1/4th second
143 * as cutoff for this rounding as an extreme upper bound for this.
144 * But never round down if @force_up is set.
146 if (rem
< HZ
/4 && !force_up
) /* round down */
151 /* now that we have rounded, subtract the extra skew again */
154 if (j
<= jiffies
) /* rounding ate our timeout entirely; */
160 * __round_jiffies - function to round jiffies to a full second
161 * @j: the time in (absolute) jiffies that should be rounded
162 * @cpu: the processor number on which the timeout will happen
164 * __round_jiffies() rounds an absolute time in the future (in jiffies)
165 * up or down to (approximately) full seconds. This is useful for timers
166 * for which the exact time they fire does not matter too much, as long as
167 * they fire approximately every X seconds.
169 * By rounding these timers to whole seconds, all such timers will fire
170 * at the same time, rather than at various times spread out. The goal
171 * of this is to have the CPU wake up less, which saves power.
173 * The exact rounding is skewed for each processor to avoid all
174 * processors firing at the exact same time, which could lead
175 * to lock contention or spurious cache line bouncing.
177 * The return value is the rounded version of the @j parameter.
179 unsigned long __round_jiffies(unsigned long j
, int cpu
)
181 return round_jiffies_common(j
, cpu
, false);
183 EXPORT_SYMBOL_GPL(__round_jiffies
);
186 * __round_jiffies_relative - function to round jiffies to a full second
187 * @j: the time in (relative) jiffies that should be rounded
188 * @cpu: the processor number on which the timeout will happen
190 * __round_jiffies_relative() rounds a time delta in the future (in jiffies)
191 * up or down to (approximately) full seconds. This is useful for timers
192 * for which the exact time they fire does not matter too much, as long as
193 * they fire approximately every X seconds.
195 * By rounding these timers to whole seconds, all such timers will fire
196 * at the same time, rather than at various times spread out. The goal
197 * of this is to have the CPU wake up less, which saves power.
199 * The exact rounding is skewed for each processor to avoid all
200 * processors firing at the exact same time, which could lead
201 * to lock contention or spurious cache line bouncing.
203 * The return value is the rounded version of the @j parameter.
205 unsigned long __round_jiffies_relative(unsigned long j
, int cpu
)
207 unsigned long j0
= jiffies
;
209 /* Use j0 because jiffies might change while we run */
210 return round_jiffies_common(j
+ j0
, cpu
, false) - j0
;
212 EXPORT_SYMBOL_GPL(__round_jiffies_relative
);
215 * round_jiffies - function to round jiffies to a full second
216 * @j: the time in (absolute) jiffies that should be rounded
218 * round_jiffies() rounds an absolute time in the future (in jiffies)
219 * up or down to (approximately) full seconds. This is useful for timers
220 * for which the exact time they fire does not matter too much, as long as
221 * they fire approximately every X seconds.
223 * By rounding these timers to whole seconds, all such timers will fire
224 * at the same time, rather than at various times spread out. The goal
225 * of this is to have the CPU wake up less, which saves power.
227 * The return value is the rounded version of the @j parameter.
229 unsigned long round_jiffies(unsigned long j
)
231 return round_jiffies_common(j
, raw_smp_processor_id(), false);
233 EXPORT_SYMBOL_GPL(round_jiffies
);
236 * round_jiffies_relative - function to round jiffies to a full second
237 * @j: the time in (relative) jiffies that should be rounded
239 * round_jiffies_relative() rounds a time delta in the future (in jiffies)
240 * up or down to (approximately) full seconds. This is useful for timers
241 * for which the exact time they fire does not matter too much, as long as
242 * they fire approximately every X seconds.
244 * By rounding these timers to whole seconds, all such timers will fire
245 * at the same time, rather than at various times spread out. The goal
246 * of this is to have the CPU wake up less, which saves power.
248 * The return value is the rounded version of the @j parameter.
250 unsigned long round_jiffies_relative(unsigned long j
)
252 return __round_jiffies_relative(j
, raw_smp_processor_id());
254 EXPORT_SYMBOL_GPL(round_jiffies_relative
);
257 * __round_jiffies_up - function to round jiffies up to a full second
258 * @j: the time in (absolute) jiffies that should be rounded
259 * @cpu: the processor number on which the timeout will happen
261 * This is the same as __round_jiffies() except that it will never
262 * round down. This is useful for timeouts for which the exact time
263 * of firing does not matter too much, as long as they don't fire too
266 unsigned long __round_jiffies_up(unsigned long j
, int cpu
)
268 return round_jiffies_common(j
, cpu
, true);
270 EXPORT_SYMBOL_GPL(__round_jiffies_up
);
273 * __round_jiffies_up_relative - function to round jiffies up to a full second
274 * @j: the time in (relative) jiffies that should be rounded
275 * @cpu: the processor number on which the timeout will happen
277 * This is the same as __round_jiffies_relative() except that it will never
278 * round down. This is useful for timeouts for which the exact time
279 * of firing does not matter too much, as long as they don't fire too
282 unsigned long __round_jiffies_up_relative(unsigned long j
, int cpu
)
284 unsigned long j0
= jiffies
;
286 /* Use j0 because jiffies might change while we run */
287 return round_jiffies_common(j
+ j0
, cpu
, true) - j0
;
289 EXPORT_SYMBOL_GPL(__round_jiffies_up_relative
);
292 * round_jiffies_up - function to round jiffies up to a full second
293 * @j: the time in (absolute) jiffies that should be rounded
295 * This is the same as round_jiffies() except that it will never
296 * round down. This is useful for timeouts for which the exact time
297 * of firing does not matter too much, as long as they don't fire too
300 unsigned long round_jiffies_up(unsigned long j
)
302 return round_jiffies_common(j
, raw_smp_processor_id(), true);
304 EXPORT_SYMBOL_GPL(round_jiffies_up
);
307 * round_jiffies_up_relative - function to round jiffies up to a full second
308 * @j: the time in (relative) jiffies that should be rounded
310 * This is the same as round_jiffies_relative() except that it will never
311 * round down. This is useful for timeouts for which the exact time
312 * of firing does not matter too much, as long as they don't fire too
315 unsigned long round_jiffies_up_relative(unsigned long j
)
317 return __round_jiffies_up_relative(j
, raw_smp_processor_id());
319 EXPORT_SYMBOL_GPL(round_jiffies_up_relative
);
322 * set_timer_slack - set the allowed slack for a timer
323 * @slack_hz: the amount of time (in jiffies) allowed for rounding
325 * Set the amount of time, in jiffies, that a certain timer has
326 * in terms of slack. By setting this value, the timer subsystem
327 * will schedule the actual timer somewhere between
328 * the time mod_timer() asks for, and that time plus the slack.
330 * By setting the slack to -1, a percentage of the delay is used
333 void set_timer_slack(struct timer_list
*timer
, int slack_hz
)
335 timer
->slack
= slack_hz
;
337 EXPORT_SYMBOL_GPL(set_timer_slack
);
340 static inline void set_running_timer(struct tvec_base
*base
,
341 struct timer_list
*timer
)
344 base
->running_timer
= timer
;
348 static void internal_add_timer(struct tvec_base
*base
, struct timer_list
*timer
)
350 unsigned long expires
= timer
->expires
;
351 unsigned long idx
= expires
- base
->timer_jiffies
;
352 struct list_head
*vec
;
354 if (idx
< TVR_SIZE
) {
355 int i
= expires
& TVR_MASK
;
356 vec
= base
->tv1
.vec
+ i
;
357 } else if (idx
< 1 << (TVR_BITS
+ TVN_BITS
)) {
358 int i
= (expires
>> TVR_BITS
) & TVN_MASK
;
359 vec
= base
->tv2
.vec
+ i
;
360 } else if (idx
< 1 << (TVR_BITS
+ 2 * TVN_BITS
)) {
361 int i
= (expires
>> (TVR_BITS
+ TVN_BITS
)) & TVN_MASK
;
362 vec
= base
->tv3
.vec
+ i
;
363 } else if (idx
< 1 << (TVR_BITS
+ 3 * TVN_BITS
)) {
364 int i
= (expires
>> (TVR_BITS
+ 2 * TVN_BITS
)) & TVN_MASK
;
365 vec
= base
->tv4
.vec
+ i
;
366 } else if ((signed long) idx
< 0) {
368 * Can happen if you add a timer with expires == jiffies,
369 * or you set a timer to go off in the past
371 vec
= base
->tv1
.vec
+ (base
->timer_jiffies
& TVR_MASK
);
374 /* If the timeout is larger than 0xffffffff on 64-bit
375 * architectures then we use the maximum timeout:
377 if (idx
> 0xffffffffUL
) {
379 expires
= idx
+ base
->timer_jiffies
;
381 i
= (expires
>> (TVR_BITS
+ 3 * TVN_BITS
)) & TVN_MASK
;
382 vec
= base
->tv5
.vec
+ i
;
387 list_add_tail(&timer
->entry
, vec
);
390 #ifdef CONFIG_TIMER_STATS
391 void __timer_stats_timer_set_start_info(struct timer_list
*timer
, void *addr
)
393 if (timer
->start_site
)
396 timer
->start_site
= addr
;
397 memcpy(timer
->start_comm
, current
->comm
, TASK_COMM_LEN
);
398 timer
->start_pid
= current
->pid
;
401 static void timer_stats_account_timer(struct timer_list
*timer
)
403 unsigned int flag
= 0;
405 if (likely(!timer
->start_site
))
407 if (unlikely(tbase_get_deferrable(timer
->base
)))
408 flag
|= TIMER_STATS_FLAG_DEFERRABLE
;
410 timer_stats_update_stats(timer
, timer
->start_pid
, timer
->start_site
,
411 timer
->function
, timer
->start_comm
, flag
);
415 static void timer_stats_account_timer(struct timer_list
*timer
) {}
418 #ifdef CONFIG_DEBUG_OBJECTS_TIMERS
420 static struct debug_obj_descr timer_debug_descr
;
423 * fixup_init is called when:
424 * - an active object is initialized
426 static int timer_fixup_init(void *addr
, enum debug_obj_state state
)
428 struct timer_list
*timer
= addr
;
431 case ODEBUG_STATE_ACTIVE
:
432 del_timer_sync(timer
);
433 debug_object_init(timer
, &timer_debug_descr
);
441 * fixup_activate is called when:
442 * - an active object is activated
443 * - an unknown object is activated (might be a statically initialized object)
445 static int timer_fixup_activate(void *addr
, enum debug_obj_state state
)
447 struct timer_list
*timer
= addr
;
451 case ODEBUG_STATE_NOTAVAILABLE
:
453 * This is not really a fixup. The timer was
454 * statically initialized. We just make sure that it
455 * is tracked in the object tracker.
457 if (timer
->entry
.next
== NULL
&&
458 timer
->entry
.prev
== TIMER_ENTRY_STATIC
) {
459 debug_object_init(timer
, &timer_debug_descr
);
460 debug_object_activate(timer
, &timer_debug_descr
);
467 case ODEBUG_STATE_ACTIVE
:
476 * fixup_free is called when:
477 * - an active object is freed
479 static int timer_fixup_free(void *addr
, enum debug_obj_state state
)
481 struct timer_list
*timer
= addr
;
484 case ODEBUG_STATE_ACTIVE
:
485 del_timer_sync(timer
);
486 debug_object_free(timer
, &timer_debug_descr
);
493 static struct debug_obj_descr timer_debug_descr
= {
494 .name
= "timer_list",
495 .fixup_init
= timer_fixup_init
,
496 .fixup_activate
= timer_fixup_activate
,
497 .fixup_free
= timer_fixup_free
,
500 static inline void debug_timer_init(struct timer_list
*timer
)
502 debug_object_init(timer
, &timer_debug_descr
);
505 static inline void debug_timer_activate(struct timer_list
*timer
)
507 debug_object_activate(timer
, &timer_debug_descr
);
510 static inline void debug_timer_deactivate(struct timer_list
*timer
)
512 debug_object_deactivate(timer
, &timer_debug_descr
);
515 static inline void debug_timer_free(struct timer_list
*timer
)
517 debug_object_free(timer
, &timer_debug_descr
);
520 static void __init_timer(struct timer_list
*timer
,
522 struct lock_class_key
*key
);
524 void init_timer_on_stack_key(struct timer_list
*timer
,
526 struct lock_class_key
*key
)
528 debug_object_init_on_stack(timer
, &timer_debug_descr
);
529 __init_timer(timer
, name
, key
);
531 EXPORT_SYMBOL_GPL(init_timer_on_stack_key
);
533 void destroy_timer_on_stack(struct timer_list
*timer
)
535 debug_object_free(timer
, &timer_debug_descr
);
537 EXPORT_SYMBOL_GPL(destroy_timer_on_stack
);
540 static inline void debug_timer_init(struct timer_list
*timer
) { }
541 static inline void debug_timer_activate(struct timer_list
*timer
) { }
542 static inline void debug_timer_deactivate(struct timer_list
*timer
) { }
545 static inline void debug_init(struct timer_list
*timer
)
547 debug_timer_init(timer
);
548 trace_timer_init(timer
);
552 debug_activate(struct timer_list
*timer
, unsigned long expires
)
554 debug_timer_activate(timer
);
555 trace_timer_start(timer
, expires
);
558 static inline void debug_deactivate(struct timer_list
*timer
)
560 debug_timer_deactivate(timer
);
561 trace_timer_cancel(timer
);
564 static void __init_timer(struct timer_list
*timer
,
566 struct lock_class_key
*key
)
568 timer
->entry
.next
= NULL
;
569 timer
->base
= __raw_get_cpu_var(tvec_bases
);
571 #ifdef CONFIG_TIMER_STATS
572 timer
->start_site
= NULL
;
573 timer
->start_pid
= -1;
574 memset(timer
->start_comm
, 0, TASK_COMM_LEN
);
576 lockdep_init_map(&timer
->lockdep_map
, name
, key
, 0);
580 * init_timer_key - initialize a timer
581 * @timer: the timer to be initialized
582 * @name: name of the timer
583 * @key: lockdep class key of the fake lock used for tracking timer
584 * sync lock dependencies
586 * init_timer_key() must be done to a timer prior calling *any* of the
587 * other timer functions.
589 void init_timer_key(struct timer_list
*timer
,
591 struct lock_class_key
*key
)
594 __init_timer(timer
, name
, key
);
596 EXPORT_SYMBOL(init_timer_key
);
598 void init_timer_deferrable_key(struct timer_list
*timer
,
600 struct lock_class_key
*key
)
602 init_timer_key(timer
, name
, key
);
603 timer_set_deferrable(timer
);
605 EXPORT_SYMBOL(init_timer_deferrable_key
);
607 static inline void detach_timer(struct timer_list
*timer
,
610 struct list_head
*entry
= &timer
->entry
;
612 debug_deactivate(timer
);
614 __list_del(entry
->prev
, entry
->next
);
617 entry
->prev
= LIST_POISON2
;
621 * We are using hashed locking: holding per_cpu(tvec_bases).lock
622 * means that all timers which are tied to this base via timer->base are
623 * locked, and the base itself is locked too.
625 * So __run_timers/migrate_timers can safely modify all timers which could
626 * be found on ->tvX lists.
628 * When the timer's base is locked, and the timer removed from list, it is
629 * possible to set timer->base = NULL and drop the lock: the timer remains
632 static struct tvec_base
*lock_timer_base(struct timer_list
*timer
,
633 unsigned long *flags
)
634 __acquires(timer
->base
->lock
)
636 struct tvec_base
*base
;
639 struct tvec_base
*prelock_base
= timer
->base
;
640 base
= tbase_get_base(prelock_base
);
641 if (likely(base
!= NULL
)) {
642 spin_lock_irqsave(&base
->lock
, *flags
);
643 if (likely(prelock_base
== timer
->base
))
645 /* The timer has migrated to another CPU */
646 spin_unlock_irqrestore(&base
->lock
, *flags
);
653 __mod_timer(struct timer_list
*timer
, unsigned long expires
,
654 bool pending_only
, int pinned
)
656 struct tvec_base
*base
, *new_base
;
660 timer_stats_timer_set_start_info(timer
);
661 BUG_ON(!timer
->function
);
663 base
= lock_timer_base(timer
, &flags
);
665 if (timer_pending(timer
)) {
666 detach_timer(timer
, 0);
667 if (timer
->expires
== base
->next_timer
&&
668 !tbase_get_deferrable(timer
->base
))
669 base
->next_timer
= base
->timer_jiffies
;
676 debug_activate(timer
, expires
);
678 cpu
= smp_processor_id();
680 #if defined(CONFIG_NO_HZ) && defined(CONFIG_SMP)
681 if (!pinned
&& get_sysctl_timer_migration() && idle_cpu(cpu
)) {
682 int preferred_cpu
= get_nohz_load_balancer();
684 if (preferred_cpu
>= 0)
688 new_base
= per_cpu(tvec_bases
, cpu
);
690 if (base
!= new_base
) {
692 * We are trying to schedule the timer on the local CPU.
693 * However we can't change timer's base while it is running,
694 * otherwise del_timer_sync() can't detect that the timer's
695 * handler yet has not finished. This also guarantees that
696 * the timer is serialized wrt itself.
698 if (likely(base
->running_timer
!= timer
)) {
699 /* See the comment in lock_timer_base() */
700 timer_set_base(timer
, NULL
);
701 spin_unlock(&base
->lock
);
703 spin_lock(&base
->lock
);
704 timer_set_base(timer
, base
);
708 timer
->expires
= expires
;
709 if (time_before(timer
->expires
, base
->next_timer
) &&
710 !tbase_get_deferrable(timer
->base
))
711 base
->next_timer
= timer
->expires
;
712 internal_add_timer(base
, timer
);
715 spin_unlock_irqrestore(&base
->lock
, flags
);
721 * mod_timer_pending - modify a pending timer's timeout
722 * @timer: the pending timer to be modified
723 * @expires: new timeout in jiffies
725 * mod_timer_pending() is the same for pending timers as mod_timer(),
726 * but will not re-activate and modify already deleted timers.
728 * It is useful for unserialized use of timers.
730 int mod_timer_pending(struct timer_list
*timer
, unsigned long expires
)
732 return __mod_timer(timer
, expires
, true, TIMER_NOT_PINNED
);
734 EXPORT_SYMBOL(mod_timer_pending
);
737 * Decide where to put the timer while taking the slack into account
740 * 1) calculate the maximum (absolute) time
741 * 2) calculate the highest bit where the expires and new max are different
742 * 3) use this bit to make a mask
743 * 4) use the bitmask to round down the maximum time, so that all last
747 unsigned long apply_slack(struct timer_list
*timer
, unsigned long expires
)
749 unsigned long expires_limit
, mask
;
752 expires_limit
= expires
+ timer
->slack
;
754 if (timer
->slack
< 0) /* auto slack: use 0.4% */
755 expires_limit
= expires
+ (expires
- jiffies
)/256;
757 mask
= expires
^ expires_limit
;
762 bit
= find_last_bit(&mask
, BITS_PER_LONG
);
764 mask
= (1 << bit
) - 1;
766 expires_limit
= expires_limit
& ~(mask
);
768 return expires_limit
;
772 * mod_timer - modify a timer's timeout
773 * @timer: the timer to be modified
774 * @expires: new timeout in jiffies
776 * mod_timer() is a more efficient way to update the expire field of an
777 * active timer (if the timer is inactive it will be activated)
779 * mod_timer(timer, expires) is equivalent to:
781 * del_timer(timer); timer->expires = expires; add_timer(timer);
783 * Note that if there are multiple unserialized concurrent users of the
784 * same timer, then mod_timer() is the only safe way to modify the timeout,
785 * since add_timer() cannot modify an already running timer.
787 * The function returns whether it has modified a pending timer or not.
788 * (ie. mod_timer() of an inactive timer returns 0, mod_timer() of an
789 * active timer returns 1.)
791 int mod_timer(struct timer_list
*timer
, unsigned long expires
)
794 * This is a common optimization triggered by the
795 * networking code - if the timer is re-modified
796 * to be the same thing then just return:
798 if (timer_pending(timer
) && timer
->expires
== expires
)
801 expires
= apply_slack(timer
, expires
);
803 return __mod_timer(timer
, expires
, false, TIMER_NOT_PINNED
);
805 EXPORT_SYMBOL(mod_timer
);
808 * mod_timer_pinned - modify a timer's timeout
809 * @timer: the timer to be modified
810 * @expires: new timeout in jiffies
812 * mod_timer_pinned() is a way to update the expire field of an
813 * active timer (if the timer is inactive it will be activated)
814 * and not allow the timer to be migrated to a different CPU.
816 * mod_timer_pinned(timer, expires) is equivalent to:
818 * del_timer(timer); timer->expires = expires; add_timer(timer);
820 int mod_timer_pinned(struct timer_list
*timer
, unsigned long expires
)
822 if (timer
->expires
== expires
&& timer_pending(timer
))
825 return __mod_timer(timer
, expires
, false, TIMER_PINNED
);
827 EXPORT_SYMBOL(mod_timer_pinned
);
830 * add_timer - start a timer
831 * @timer: the timer to be added
833 * The kernel will do a ->function(->data) callback from the
834 * timer interrupt at the ->expires point in the future. The
835 * current time is 'jiffies'.
837 * The timer's ->expires, ->function (and if the handler uses it, ->data)
838 * fields must be set prior calling this function.
840 * Timers with an ->expires field in the past will be executed in the next
843 void add_timer(struct timer_list
*timer
)
845 BUG_ON(timer_pending(timer
));
846 mod_timer(timer
, timer
->expires
);
848 EXPORT_SYMBOL(add_timer
);
851 * add_timer_on - start a timer on a particular CPU
852 * @timer: the timer to be added
853 * @cpu: the CPU to start it on
855 * This is not very scalable on SMP. Double adds are not possible.
857 void add_timer_on(struct timer_list
*timer
, int cpu
)
859 struct tvec_base
*base
= per_cpu(tvec_bases
, cpu
);
862 timer_stats_timer_set_start_info(timer
);
863 BUG_ON(timer_pending(timer
) || !timer
->function
);
864 spin_lock_irqsave(&base
->lock
, flags
);
865 timer_set_base(timer
, base
);
866 debug_activate(timer
, timer
->expires
);
867 if (time_before(timer
->expires
, base
->next_timer
) &&
868 !tbase_get_deferrable(timer
->base
))
869 base
->next_timer
= timer
->expires
;
870 internal_add_timer(base
, timer
);
872 * Check whether the other CPU is idle and needs to be
873 * triggered to reevaluate the timer wheel when nohz is
874 * active. We are protected against the other CPU fiddling
875 * with the timer by holding the timer base lock. This also
876 * makes sure that a CPU on the way to idle can not evaluate
879 wake_up_idle_cpu(cpu
);
880 spin_unlock_irqrestore(&base
->lock
, flags
);
882 EXPORT_SYMBOL_GPL(add_timer_on
);
885 * del_timer - deactive a timer.
886 * @timer: the timer to be deactivated
888 * del_timer() deactivates a timer - this works on both active and inactive
891 * The function returns whether it has deactivated a pending timer or not.
892 * (ie. del_timer() of an inactive timer returns 0, del_timer() of an
893 * active timer returns 1.)
895 int del_timer(struct timer_list
*timer
)
897 struct tvec_base
*base
;
901 timer_stats_timer_clear_start_info(timer
);
902 if (timer_pending(timer
)) {
903 base
= lock_timer_base(timer
, &flags
);
904 if (timer_pending(timer
)) {
905 detach_timer(timer
, 1);
906 if (timer
->expires
== base
->next_timer
&&
907 !tbase_get_deferrable(timer
->base
))
908 base
->next_timer
= base
->timer_jiffies
;
911 spin_unlock_irqrestore(&base
->lock
, flags
);
916 EXPORT_SYMBOL(del_timer
);
920 * try_to_del_timer_sync - Try to deactivate a timer
921 * @timer: timer do del
923 * This function tries to deactivate a timer. Upon successful (ret >= 0)
924 * exit the timer is not queued and the handler is not running on any CPU.
926 * It must not be called from interrupt contexts.
928 int try_to_del_timer_sync(struct timer_list
*timer
)
930 struct tvec_base
*base
;
934 base
= lock_timer_base(timer
, &flags
);
936 if (base
->running_timer
== timer
)
940 if (timer_pending(timer
)) {
941 detach_timer(timer
, 1);
942 if (timer
->expires
== base
->next_timer
&&
943 !tbase_get_deferrable(timer
->base
))
944 base
->next_timer
= base
->timer_jiffies
;
948 spin_unlock_irqrestore(&base
->lock
, flags
);
952 EXPORT_SYMBOL(try_to_del_timer_sync
);
955 * del_timer_sync - deactivate a timer and wait for the handler to finish.
956 * @timer: the timer to be deactivated
958 * This function only differs from del_timer() on SMP: besides deactivating
959 * the timer it also makes sure the handler has finished executing on other
962 * Synchronization rules: Callers must prevent restarting of the timer,
963 * otherwise this function is meaningless. It must not be called from
964 * interrupt contexts. The caller must not hold locks which would prevent
965 * completion of the timer's handler. The timer's handler must not call
966 * add_timer_on(). Upon exit the timer is not queued and the handler is
967 * not running on any CPU.
969 * The function returns whether it has deactivated a pending timer or not.
971 int del_timer_sync(struct timer_list
*timer
)
973 #ifdef CONFIG_LOCKDEP
976 local_irq_save(flags
);
977 lock_map_acquire(&timer
->lockdep_map
);
978 lock_map_release(&timer
->lockdep_map
);
979 local_irq_restore(flags
);
983 int ret
= try_to_del_timer_sync(timer
);
989 EXPORT_SYMBOL(del_timer_sync
);
992 static int cascade(struct tvec_base
*base
, struct tvec
*tv
, int index
)
994 /* cascade all the timers from tv up one level */
995 struct timer_list
*timer
, *tmp
;
996 struct list_head tv_list
;
998 list_replace_init(tv
->vec
+ index
, &tv_list
);
1001 * We are removing _all_ timers from the list, so we
1002 * don't have to detach them individually.
1004 list_for_each_entry_safe(timer
, tmp
, &tv_list
, entry
) {
1005 BUG_ON(tbase_get_base(timer
->base
) != base
);
1006 internal_add_timer(base
, timer
);
1012 static void call_timer_fn(struct timer_list
*timer
, void (*fn
)(unsigned long),
1015 int preempt_count
= preempt_count();
1017 #ifdef CONFIG_LOCKDEP
1019 * It is permissible to free the timer from inside the
1020 * function that is called from it, this we need to take into
1021 * account for lockdep too. To avoid bogus "held lock freed"
1022 * warnings as well as problems when looking into
1023 * timer->lockdep_map, make a copy and use that here.
1025 struct lockdep_map lockdep_map
= timer
->lockdep_map
;
1028 * Couple the lock chain with the lock chain at
1029 * del_timer_sync() by acquiring the lock_map around the fn()
1030 * call here and in del_timer_sync().
1032 lock_map_acquire(&lockdep_map
);
1034 trace_timer_expire_entry(timer
);
1036 trace_timer_expire_exit(timer
);
1038 lock_map_release(&lockdep_map
);
1040 if (preempt_count
!= preempt_count()) {
1041 WARN_ONCE(1, "timer: %pF preempt leak: %08x -> %08x\n",
1042 fn
, preempt_count
, preempt_count());
1044 * Restore the preempt count. That gives us a decent
1045 * chance to survive and extract information. If the
1046 * callback kept a lock held, bad luck, but not worse
1047 * than the BUG() we had.
1049 preempt_count() = preempt_count
;
1053 #define INDEX(N) ((base->timer_jiffies >> (TVR_BITS + (N) * TVN_BITS)) & TVN_MASK)
1056 * __run_timers - run all expired timers (if any) on this CPU.
1057 * @base: the timer vector to be processed.
1059 * This function cascades all vectors and executes all expired timer
1062 static inline void __run_timers(struct tvec_base
*base
)
1064 struct timer_list
*timer
;
1066 spin_lock_irq(&base
->lock
);
1067 while (time_after_eq(jiffies
, base
->timer_jiffies
)) {
1068 struct list_head work_list
;
1069 struct list_head
*head
= &work_list
;
1070 int index
= base
->timer_jiffies
& TVR_MASK
;
1076 (!cascade(base
, &base
->tv2
, INDEX(0))) &&
1077 (!cascade(base
, &base
->tv3
, INDEX(1))) &&
1078 !cascade(base
, &base
->tv4
, INDEX(2)))
1079 cascade(base
, &base
->tv5
, INDEX(3));
1080 ++base
->timer_jiffies
;
1081 list_replace_init(base
->tv1
.vec
+ index
, &work_list
);
1082 while (!list_empty(head
)) {
1083 void (*fn
)(unsigned long);
1086 timer
= list_first_entry(head
, struct timer_list
,entry
);
1087 fn
= timer
->function
;
1090 timer_stats_account_timer(timer
);
1092 set_running_timer(base
, timer
);
1093 detach_timer(timer
, 1);
1095 spin_unlock_irq(&base
->lock
);
1096 call_timer_fn(timer
, fn
, data
);
1097 spin_lock_irq(&base
->lock
);
1100 set_running_timer(base
, NULL
);
1101 spin_unlock_irq(&base
->lock
);
1106 * Find out when the next timer event is due to happen. This
1107 * is used on S/390 to stop all activity when a CPU is idle.
1108 * This function needs to be called with interrupts disabled.
1110 static unsigned long __next_timer_interrupt(struct tvec_base
*base
)
1112 unsigned long timer_jiffies
= base
->timer_jiffies
;
1113 unsigned long expires
= timer_jiffies
+ NEXT_TIMER_MAX_DELTA
;
1114 int index
, slot
, array
, found
= 0;
1115 struct timer_list
*nte
;
1116 struct tvec
*varray
[4];
1118 /* Look for timer events in tv1. */
1119 index
= slot
= timer_jiffies
& TVR_MASK
;
1121 list_for_each_entry(nte
, base
->tv1
.vec
+ slot
, entry
) {
1122 if (tbase_get_deferrable(nte
->base
))
1126 expires
= nte
->expires
;
1127 /* Look at the cascade bucket(s)? */
1128 if (!index
|| slot
< index
)
1132 slot
= (slot
+ 1) & TVR_MASK
;
1133 } while (slot
!= index
);
1136 /* Calculate the next cascade event */
1138 timer_jiffies
+= TVR_SIZE
- index
;
1139 timer_jiffies
>>= TVR_BITS
;
1141 /* Check tv2-tv5. */
1142 varray
[0] = &base
->tv2
;
1143 varray
[1] = &base
->tv3
;
1144 varray
[2] = &base
->tv4
;
1145 varray
[3] = &base
->tv5
;
1147 for (array
= 0; array
< 4; array
++) {
1148 struct tvec
*varp
= varray
[array
];
1150 index
= slot
= timer_jiffies
& TVN_MASK
;
1152 list_for_each_entry(nte
, varp
->vec
+ slot
, entry
) {
1153 if (tbase_get_deferrable(nte
->base
))
1157 if (time_before(nte
->expires
, expires
))
1158 expires
= nte
->expires
;
1161 * Do we still search for the first timer or are
1162 * we looking up the cascade buckets ?
1165 /* Look at the cascade bucket(s)? */
1166 if (!index
|| slot
< index
)
1170 slot
= (slot
+ 1) & TVN_MASK
;
1171 } while (slot
!= index
);
1174 timer_jiffies
+= TVN_SIZE
- index
;
1175 timer_jiffies
>>= TVN_BITS
;
1181 * Check, if the next hrtimer event is before the next timer wheel
1184 static unsigned long cmp_next_hrtimer_event(unsigned long now
,
1185 unsigned long expires
)
1187 ktime_t hr_delta
= hrtimer_get_next_event();
1188 struct timespec tsdelta
;
1189 unsigned long delta
;
1191 if (hr_delta
.tv64
== KTIME_MAX
)
1195 * Expired timer available, let it expire in the next tick
1197 if (hr_delta
.tv64
<= 0)
1200 tsdelta
= ktime_to_timespec(hr_delta
);
1201 delta
= timespec_to_jiffies(&tsdelta
);
1204 * Limit the delta to the max value, which is checked in
1205 * tick_nohz_stop_sched_tick():
1207 if (delta
> NEXT_TIMER_MAX_DELTA
)
1208 delta
= NEXT_TIMER_MAX_DELTA
;
1211 * Take rounding errors in to account and make sure, that it
1212 * expires in the next tick. Otherwise we go into an endless
1213 * ping pong due to tick_nohz_stop_sched_tick() retriggering
1219 if (time_before(now
, expires
))
1225 * get_next_timer_interrupt - return the jiffy of the next pending timer
1226 * @now: current time (in jiffies)
1228 unsigned long get_next_timer_interrupt(unsigned long now
)
1230 struct tvec_base
*base
= __get_cpu_var(tvec_bases
);
1231 unsigned long expires
;
1233 spin_lock(&base
->lock
);
1234 if (time_before_eq(base
->next_timer
, base
->timer_jiffies
))
1235 base
->next_timer
= __next_timer_interrupt(base
);
1236 expires
= base
->next_timer
;
1237 spin_unlock(&base
->lock
);
1239 if (time_before_eq(expires
, now
))
1242 return cmp_next_hrtimer_event(now
, expires
);
1247 * Called from the timer interrupt handler to charge one tick to the current
1248 * process. user_tick is 1 if the tick is user time, 0 for system.
1250 void update_process_times(int user_tick
)
1252 struct task_struct
*p
= current
;
1253 int cpu
= smp_processor_id();
1255 /* Note: this timer irq context must be accounted for as well. */
1256 account_process_tick(p
, user_tick
);
1258 rcu_check_callbacks(cpu
, user_tick
);
1260 perf_event_do_pending();
1262 run_posix_cpu_timers(p
);
1266 * This function runs timers and the timer-tq in bottom half context.
1268 static void run_timer_softirq(struct softirq_action
*h
)
1270 struct tvec_base
*base
= __get_cpu_var(tvec_bases
);
1272 hrtimer_run_pending();
1274 if (time_after_eq(jiffies
, base
->timer_jiffies
))
1279 * Called by the local, per-CPU timer interrupt on SMP.
1281 void run_local_timers(void)
1283 hrtimer_run_queues();
1284 raise_softirq(TIMER_SOFTIRQ
);
1289 * The 64-bit jiffies value is not atomic - you MUST NOT read it
1290 * without sampling the sequence number in xtime_lock.
1291 * jiffies is defined in the linker script...
1294 void do_timer(unsigned long ticks
)
1296 jiffies_64
+= ticks
;
1301 #ifdef __ARCH_WANT_SYS_ALARM
1304 * For backwards compatibility? This can be done in libc so Alpha
1305 * and all newer ports shouldn't need it.
1307 SYSCALL_DEFINE1(alarm
, unsigned int, seconds
)
1309 return alarm_setitimer(seconds
);
1317 * The Alpha uses getxpid, getxuid, and getxgid instead. Maybe this
1318 * should be moved into arch/i386 instead?
1322 * sys_getpid - return the thread group id of the current process
1324 * Note, despite the name, this returns the tgid not the pid. The tgid and
1325 * the pid are identical unless CLONE_THREAD was specified on clone() in
1326 * which case the tgid is the same in all threads of the same group.
1328 * This is SMP safe as current->tgid does not change.
1330 SYSCALL_DEFINE0(getpid
)
1332 return task_tgid_vnr(current
);
1336 * Accessing ->real_parent is not SMP-safe, it could
1337 * change from under us. However, we can use a stale
1338 * value of ->real_parent under rcu_read_lock(), see
1339 * release_task()->call_rcu(delayed_put_task_struct).
1341 SYSCALL_DEFINE0(getppid
)
1346 pid
= task_tgid_vnr(current
->real_parent
);
1352 SYSCALL_DEFINE0(getuid
)
1354 /* Only we change this so SMP safe */
1355 return current_uid();
1358 SYSCALL_DEFINE0(geteuid
)
1360 /* Only we change this so SMP safe */
1361 return current_euid();
1364 SYSCALL_DEFINE0(getgid
)
1366 /* Only we change this so SMP safe */
1367 return current_gid();
1370 SYSCALL_DEFINE0(getegid
)
1372 /* Only we change this so SMP safe */
1373 return current_egid();
1378 static void process_timeout(unsigned long __data
)
1380 wake_up_process((struct task_struct
*)__data
);
1384 * schedule_timeout - sleep until timeout
1385 * @timeout: timeout value in jiffies
1387 * Make the current task sleep until @timeout jiffies have
1388 * elapsed. The routine will return immediately unless
1389 * the current task state has been set (see set_current_state()).
1391 * You can set the task state as follows -
1393 * %TASK_UNINTERRUPTIBLE - at least @timeout jiffies are guaranteed to
1394 * pass before the routine returns. The routine will return 0
1396 * %TASK_INTERRUPTIBLE - the routine may return early if a signal is
1397 * delivered to the current task. In this case the remaining time
1398 * in jiffies will be returned, or 0 if the timer expired in time
1400 * The current task state is guaranteed to be TASK_RUNNING when this
1403 * Specifying a @timeout value of %MAX_SCHEDULE_TIMEOUT will schedule
1404 * the CPU away without a bound on the timeout. In this case the return
1405 * value will be %MAX_SCHEDULE_TIMEOUT.
1407 * In all cases the return value is guaranteed to be non-negative.
1409 signed long __sched
schedule_timeout(signed long timeout
)
1411 struct timer_list timer
;
1412 unsigned long expire
;
1416 case MAX_SCHEDULE_TIMEOUT
:
1418 * These two special cases are useful to be comfortable
1419 * in the caller. Nothing more. We could take
1420 * MAX_SCHEDULE_TIMEOUT from one of the negative value
1421 * but I' d like to return a valid offset (>=0) to allow
1422 * the caller to do everything it want with the retval.
1428 * Another bit of PARANOID. Note that the retval will be
1429 * 0 since no piece of kernel is supposed to do a check
1430 * for a negative retval of schedule_timeout() (since it
1431 * should never happens anyway). You just have the printk()
1432 * that will tell you if something is gone wrong and where.
1435 printk(KERN_ERR
"schedule_timeout: wrong timeout "
1436 "value %lx\n", timeout
);
1438 current
->state
= TASK_RUNNING
;
1443 expire
= timeout
+ jiffies
;
1445 setup_timer_on_stack(&timer
, process_timeout
, (unsigned long)current
);
1446 __mod_timer(&timer
, expire
, false, TIMER_NOT_PINNED
);
1448 del_singleshot_timer_sync(&timer
);
1450 /* Remove the timer from the object tracker */
1451 destroy_timer_on_stack(&timer
);
1453 timeout
= expire
- jiffies
;
1456 return timeout
< 0 ? 0 : timeout
;
1458 EXPORT_SYMBOL(schedule_timeout
);
1461 * We can use __set_current_state() here because schedule_timeout() calls
1462 * schedule() unconditionally.
1464 signed long __sched
schedule_timeout_interruptible(signed long timeout
)
1466 __set_current_state(TASK_INTERRUPTIBLE
);
1467 return schedule_timeout(timeout
);
1469 EXPORT_SYMBOL(schedule_timeout_interruptible
);
1471 signed long __sched
schedule_timeout_killable(signed long timeout
)
1473 __set_current_state(TASK_KILLABLE
);
1474 return schedule_timeout(timeout
);
1476 EXPORT_SYMBOL(schedule_timeout_killable
);
1478 signed long __sched
schedule_timeout_uninterruptible(signed long timeout
)
1480 __set_current_state(TASK_UNINTERRUPTIBLE
);
1481 return schedule_timeout(timeout
);
1483 EXPORT_SYMBOL(schedule_timeout_uninterruptible
);
1485 /* Thread ID - the internal kernel "pid" */
1486 SYSCALL_DEFINE0(gettid
)
1488 return task_pid_vnr(current
);
1492 * do_sysinfo - fill in sysinfo struct
1493 * @info: pointer to buffer to fill
1495 int do_sysinfo(struct sysinfo
*info
)
1497 unsigned long mem_total
, sav_total
;
1498 unsigned int mem_unit
, bitcount
;
1501 memset(info
, 0, sizeof(struct sysinfo
));
1504 monotonic_to_bootbased(&tp
);
1505 info
->uptime
= tp
.tv_sec
+ (tp
.tv_nsec
? 1 : 0);
1507 get_avenrun(info
->loads
, 0, SI_LOAD_SHIFT
- FSHIFT
);
1509 info
->procs
= nr_threads
;
1515 * If the sum of all the available memory (i.e. ram + swap)
1516 * is less than can be stored in a 32 bit unsigned long then
1517 * we can be binary compatible with 2.2.x kernels. If not,
1518 * well, in that case 2.2.x was broken anyways...
1520 * -Erik Andersen <andersee@debian.org>
1523 mem_total
= info
->totalram
+ info
->totalswap
;
1524 if (mem_total
< info
->totalram
|| mem_total
< info
->totalswap
)
1527 mem_unit
= info
->mem_unit
;
1528 while (mem_unit
> 1) {
1531 sav_total
= mem_total
;
1533 if (mem_total
< sav_total
)
1538 * If mem_total did not overflow, multiply all memory values by
1539 * info->mem_unit and set it to 1. This leaves things compatible
1540 * with 2.2.x, and also retains compatibility with earlier 2.4.x
1545 info
->totalram
<<= bitcount
;
1546 info
->freeram
<<= bitcount
;
1547 info
->sharedram
<<= bitcount
;
1548 info
->bufferram
<<= bitcount
;
1549 info
->totalswap
<<= bitcount
;
1550 info
->freeswap
<<= bitcount
;
1551 info
->totalhigh
<<= bitcount
;
1552 info
->freehigh
<<= bitcount
;
1558 SYSCALL_DEFINE1(sysinfo
, struct sysinfo __user
*, info
)
1564 if (copy_to_user(info
, &val
, sizeof(struct sysinfo
)))
1570 static int __cpuinit
init_timers_cpu(int cpu
)
1573 struct tvec_base
*base
;
1574 static char __cpuinitdata tvec_base_done
[NR_CPUS
];
1576 if (!tvec_base_done
[cpu
]) {
1577 static char boot_done
;
1581 * The APs use this path later in boot
1583 base
= kmalloc_node(sizeof(*base
),
1584 GFP_KERNEL
| __GFP_ZERO
,
1589 /* Make sure that tvec_base is 2 byte aligned */
1590 if (tbase_get_deferrable(base
)) {
1595 per_cpu(tvec_bases
, cpu
) = base
;
1598 * This is for the boot CPU - we use compile-time
1599 * static initialisation because per-cpu memory isn't
1600 * ready yet and because the memory allocators are not
1601 * initialised either.
1604 base
= &boot_tvec_bases
;
1606 tvec_base_done
[cpu
] = 1;
1608 base
= per_cpu(tvec_bases
, cpu
);
1611 spin_lock_init(&base
->lock
);
1613 for (j
= 0; j
< TVN_SIZE
; j
++) {
1614 INIT_LIST_HEAD(base
->tv5
.vec
+ j
);
1615 INIT_LIST_HEAD(base
->tv4
.vec
+ j
);
1616 INIT_LIST_HEAD(base
->tv3
.vec
+ j
);
1617 INIT_LIST_HEAD(base
->tv2
.vec
+ j
);
1619 for (j
= 0; j
< TVR_SIZE
; j
++)
1620 INIT_LIST_HEAD(base
->tv1
.vec
+ j
);
1622 base
->timer_jiffies
= jiffies
;
1623 base
->next_timer
= base
->timer_jiffies
;
1627 #ifdef CONFIG_HOTPLUG_CPU
1628 static void migrate_timer_list(struct tvec_base
*new_base
, struct list_head
*head
)
1630 struct timer_list
*timer
;
1632 while (!list_empty(head
)) {
1633 timer
= list_first_entry(head
, struct timer_list
, entry
);
1634 detach_timer(timer
, 0);
1635 timer_set_base(timer
, new_base
);
1636 if (time_before(timer
->expires
, new_base
->next_timer
) &&
1637 !tbase_get_deferrable(timer
->base
))
1638 new_base
->next_timer
= timer
->expires
;
1639 internal_add_timer(new_base
, timer
);
1643 static void __cpuinit
migrate_timers(int cpu
)
1645 struct tvec_base
*old_base
;
1646 struct tvec_base
*new_base
;
1649 BUG_ON(cpu_online(cpu
));
1650 old_base
= per_cpu(tvec_bases
, cpu
);
1651 new_base
= get_cpu_var(tvec_bases
);
1653 * The caller is globally serialized and nobody else
1654 * takes two locks at once, deadlock is not possible.
1656 spin_lock_irq(&new_base
->lock
);
1657 spin_lock_nested(&old_base
->lock
, SINGLE_DEPTH_NESTING
);
1659 BUG_ON(old_base
->running_timer
);
1661 for (i
= 0; i
< TVR_SIZE
; i
++)
1662 migrate_timer_list(new_base
, old_base
->tv1
.vec
+ i
);
1663 for (i
= 0; i
< TVN_SIZE
; i
++) {
1664 migrate_timer_list(new_base
, old_base
->tv2
.vec
+ i
);
1665 migrate_timer_list(new_base
, old_base
->tv3
.vec
+ i
);
1666 migrate_timer_list(new_base
, old_base
->tv4
.vec
+ i
);
1667 migrate_timer_list(new_base
, old_base
->tv5
.vec
+ i
);
1670 spin_unlock(&old_base
->lock
);
1671 spin_unlock_irq(&new_base
->lock
);
1672 put_cpu_var(tvec_bases
);
1674 #endif /* CONFIG_HOTPLUG_CPU */
1676 static int __cpuinit
timer_cpu_notify(struct notifier_block
*self
,
1677 unsigned long action
, void *hcpu
)
1679 long cpu
= (long)hcpu
;
1681 case CPU_UP_PREPARE
:
1682 case CPU_UP_PREPARE_FROZEN
:
1683 if (init_timers_cpu(cpu
) < 0)
1686 #ifdef CONFIG_HOTPLUG_CPU
1688 case CPU_DEAD_FROZEN
:
1689 migrate_timers(cpu
);
1698 static struct notifier_block __cpuinitdata timers_nb
= {
1699 .notifier_call
= timer_cpu_notify
,
1703 void __init
init_timers(void)
1705 int err
= timer_cpu_notify(&timers_nb
, (unsigned long)CPU_UP_PREPARE
,
1706 (void *)(long)smp_processor_id());
1710 BUG_ON(err
== NOTIFY_BAD
);
1711 register_cpu_notifier(&timers_nb
);
1712 open_softirq(TIMER_SOFTIRQ
, run_timer_softirq
);
1716 * msleep - sleep safely even with waitqueue interruptions
1717 * @msecs: Time in milliseconds to sleep for
1719 void msleep(unsigned int msecs
)
1721 unsigned long timeout
= msecs_to_jiffies(msecs
) + 1;
1724 timeout
= schedule_timeout_uninterruptible(timeout
);
1727 EXPORT_SYMBOL(msleep
);
1730 * msleep_interruptible - sleep waiting for signals
1731 * @msecs: Time in milliseconds to sleep for
1733 unsigned long msleep_interruptible(unsigned int msecs
)
1735 unsigned long timeout
= msecs_to_jiffies(msecs
) + 1;
1737 while (timeout
&& !signal_pending(current
))
1738 timeout
= schedule_timeout_interruptible(timeout
);
1739 return jiffies_to_msecs(timeout
);
1742 EXPORT_SYMBOL(msleep_interruptible
);