aboutsummaryrefslogtreecommitdiffstats
path: root/kernel/timer.c
diff options
context:
space:
mode:
Diffstat (limited to 'kernel/timer.c')
-rw-r--r--kernel/timer.c64
1 files changed, 55 insertions, 9 deletions
diff --git a/kernel/timer.c b/kernel/timer.c
index a3d25f415019..5db5a8d26811 100644
--- a/kernel/timer.c
+++ b/kernel/timer.c
@@ -37,7 +37,7 @@
37#include <linux/delay.h> 37#include <linux/delay.h>
38#include <linux/tick.h> 38#include <linux/tick.h>
39#include <linux/kallsyms.h> 39#include <linux/kallsyms.h>
40#include <linux/perf_counter.h> 40#include <linux/perf_event.h>
41#include <linux/sched.h> 41#include <linux/sched.h>
42 42
43#include <asm/uaccess.h> 43#include <asm/uaccess.h>
@@ -46,6 +46,9 @@
46#include <asm/timex.h> 46#include <asm/timex.h>
47#include <asm/io.h> 47#include <asm/io.h>
48 48
49#define CREATE_TRACE_POINTS
50#include <trace/events/timer.h>
51
49u64 jiffies_64 __cacheline_aligned_in_smp = INITIAL_JIFFIES; 52u64 jiffies_64 __cacheline_aligned_in_smp = INITIAL_JIFFIES;
50 53
51EXPORT_SYMBOL(jiffies_64); 54EXPORT_SYMBOL(jiffies_64);
@@ -72,6 +75,7 @@ struct tvec_base {
72 spinlock_t lock; 75 spinlock_t lock;
73 struct timer_list *running_timer; 76 struct timer_list *running_timer;
74 unsigned long timer_jiffies; 77 unsigned long timer_jiffies;
78 unsigned long next_timer;
75 struct tvec_root tv1; 79 struct tvec_root tv1;
76 struct tvec tv2; 80 struct tvec tv2;
77 struct tvec tv3; 81 struct tvec tv3;
@@ -520,6 +524,25 @@ static inline void debug_timer_activate(struct timer_list *timer) { }
520static inline void debug_timer_deactivate(struct timer_list *timer) { } 524static inline void debug_timer_deactivate(struct timer_list *timer) { }
521#endif 525#endif
522 526
527static inline void debug_init(struct timer_list *timer)
528{
529 debug_timer_init(timer);
530 trace_timer_init(timer);
531}
532
533static inline void
534debug_activate(struct timer_list *timer, unsigned long expires)
535{
536 debug_timer_activate(timer);
537 trace_timer_start(timer, expires);
538}
539
540static inline void debug_deactivate(struct timer_list *timer)
541{
542 debug_timer_deactivate(timer);
543 trace_timer_cancel(timer);
544}
545
523static void __init_timer(struct timer_list *timer, 546static void __init_timer(struct timer_list *timer,
524 const char *name, 547 const char *name,
525 struct lock_class_key *key) 548 struct lock_class_key *key)
@@ -548,7 +571,7 @@ void init_timer_key(struct timer_list *timer,
548 const char *name, 571 const char *name,
549 struct lock_class_key *key) 572 struct lock_class_key *key)
550{ 573{
551 debug_timer_init(timer); 574 debug_init(timer);
552 __init_timer(timer, name, key); 575 __init_timer(timer, name, key);
553} 576}
554EXPORT_SYMBOL(init_timer_key); 577EXPORT_SYMBOL(init_timer_key);
@@ -567,7 +590,7 @@ static inline void detach_timer(struct timer_list *timer,
567{ 590{
568 struct list_head *entry = &timer->entry; 591 struct list_head *entry = &timer->entry;
569 592
570 debug_timer_deactivate(timer); 593 debug_deactivate(timer);
571 594
572 __list_del(entry->prev, entry->next); 595 __list_del(entry->prev, entry->next);
573 if (clear_pending) 596 if (clear_pending)
@@ -622,13 +645,16 @@ __mod_timer(struct timer_list *timer, unsigned long expires,
622 645
623 if (timer_pending(timer)) { 646 if (timer_pending(timer)) {
624 detach_timer(timer, 0); 647 detach_timer(timer, 0);
648 if (timer->expires == base->next_timer &&
649 !tbase_get_deferrable(timer->base))
650 base->next_timer = base->timer_jiffies;
625 ret = 1; 651 ret = 1;
626 } else { 652 } else {
627 if (pending_only) 653 if (pending_only)
628 goto out_unlock; 654 goto out_unlock;
629 } 655 }
630 656
631 debug_timer_activate(timer); 657 debug_activate(timer, expires);
632 658
633 new_base = __get_cpu_var(tvec_bases); 659 new_base = __get_cpu_var(tvec_bases);
634 660
@@ -663,6 +689,9 @@ __mod_timer(struct timer_list *timer, unsigned long expires,
663 } 689 }
664 690
665 timer->expires = expires; 691 timer->expires = expires;
692 if (time_before(timer->expires, base->next_timer) &&
693 !tbase_get_deferrable(timer->base))
694 base->next_timer = timer->expires;
666 internal_add_timer(base, timer); 695 internal_add_timer(base, timer);
667 696
668out_unlock: 697out_unlock:
@@ -780,7 +809,10 @@ void add_timer_on(struct timer_list *timer, int cpu)
780 BUG_ON(timer_pending(timer) || !timer->function); 809 BUG_ON(timer_pending(timer) || !timer->function);
781 spin_lock_irqsave(&base->lock, flags); 810 spin_lock_irqsave(&base->lock, flags);
782 timer_set_base(timer, base); 811 timer_set_base(timer, base);
783 debug_timer_activate(timer); 812 debug_activate(timer, timer->expires);
813 if (time_before(timer->expires, base->next_timer) &&
814 !tbase_get_deferrable(timer->base))
815 base->next_timer = timer->expires;
784 internal_add_timer(base, timer); 816 internal_add_timer(base, timer);
785 /* 817 /*
786 * Check whether the other CPU is idle and needs to be 818 * Check whether the other CPU is idle and needs to be
@@ -817,6 +849,9 @@ int del_timer(struct timer_list *timer)
817 base = lock_timer_base(timer, &flags); 849 base = lock_timer_base(timer, &flags);
818 if (timer_pending(timer)) { 850 if (timer_pending(timer)) {
819 detach_timer(timer, 1); 851 detach_timer(timer, 1);
852 if (timer->expires == base->next_timer &&
853 !tbase_get_deferrable(timer->base))
854 base->next_timer = base->timer_jiffies;
820 ret = 1; 855 ret = 1;
821 } 856 }
822 spin_unlock_irqrestore(&base->lock, flags); 857 spin_unlock_irqrestore(&base->lock, flags);
@@ -850,6 +885,9 @@ int try_to_del_timer_sync(struct timer_list *timer)
850 ret = 0; 885 ret = 0;
851 if (timer_pending(timer)) { 886 if (timer_pending(timer)) {
852 detach_timer(timer, 1); 887 detach_timer(timer, 1);
888 if (timer->expires == base->next_timer &&
889 !tbase_get_deferrable(timer->base))
890 base->next_timer = base->timer_jiffies;
853 ret = 1; 891 ret = 1;
854 } 892 }
855out: 893out:
@@ -984,7 +1022,9 @@ static inline void __run_timers(struct tvec_base *base)
984 */ 1022 */
985 lock_map_acquire(&lockdep_map); 1023 lock_map_acquire(&lockdep_map);
986 1024
1025 trace_timer_expire_entry(timer);
987 fn(data); 1026 fn(data);
1027 trace_timer_expire_exit(timer);
988 1028
989 lock_map_release(&lockdep_map); 1029 lock_map_release(&lockdep_map);
990 1030
@@ -1007,8 +1047,8 @@ static inline void __run_timers(struct tvec_base *base)
1007#ifdef CONFIG_NO_HZ 1047#ifdef CONFIG_NO_HZ
1008/* 1048/*
1009 * Find out when the next timer event is due to happen. This 1049 * Find out when the next timer event is due to happen. This
1010 * is used on S/390 to stop all activity when a cpus is idle. 1050 * is used on S/390 to stop all activity when a CPU is idle.
1011 * This functions needs to be called disabled. 1051 * This function needs to be called with interrupts disabled.
1012 */ 1052 */
1013static unsigned long __next_timer_interrupt(struct tvec_base *base) 1053static unsigned long __next_timer_interrupt(struct tvec_base *base)
1014{ 1054{
@@ -1134,7 +1174,9 @@ unsigned long get_next_timer_interrupt(unsigned long now)
1134 unsigned long expires; 1174 unsigned long expires;
1135 1175
1136 spin_lock(&base->lock); 1176 spin_lock(&base->lock);
1137 expires = __next_timer_interrupt(base); 1177 if (time_before_eq(base->next_timer, base->timer_jiffies))
1178 base->next_timer = __next_timer_interrupt(base);
1179 expires = base->next_timer;
1138 spin_unlock(&base->lock); 1180 spin_unlock(&base->lock);
1139 1181
1140 if (time_before_eq(expires, now)) 1182 if (time_before_eq(expires, now))
@@ -1169,7 +1211,7 @@ static void run_timer_softirq(struct softirq_action *h)
1169{ 1211{
1170 struct tvec_base *base = __get_cpu_var(tvec_bases); 1212 struct tvec_base *base = __get_cpu_var(tvec_bases);
1171 1213
1172 perf_counter_do_pending(); 1214 perf_event_do_pending();
1173 1215
1174 hrtimer_run_pending(); 1216 hrtimer_run_pending();
1175 1217
@@ -1522,6 +1564,7 @@ static int __cpuinit init_timers_cpu(int cpu)
1522 INIT_LIST_HEAD(base->tv1.vec + j); 1564 INIT_LIST_HEAD(base->tv1.vec + j);
1523 1565
1524 base->timer_jiffies = jiffies; 1566 base->timer_jiffies = jiffies;
1567 base->next_timer = base->timer_jiffies;
1525 return 0; 1568 return 0;
1526} 1569}
1527 1570
@@ -1534,6 +1577,9 @@ static void migrate_timer_list(struct tvec_base *new_base, struct list_head *hea
1534 timer = list_first_entry(head, struct timer_list, entry); 1577 timer = list_first_entry(head, struct timer_list, entry);
1535 detach_timer(timer, 0); 1578 detach_timer(timer, 0);
1536 timer_set_base(timer, new_base); 1579 timer_set_base(timer, new_base);
1580 if (time_before(timer->expires, new_base->next_timer) &&
1581 !tbase_get_deferrable(timer->base))
1582 new_base->next_timer = timer->expires;
1537 internal_add_timer(new_base, timer); 1583 internal_add_timer(new_base, timer);
1538 } 1584 }
1539} 1585}