include/linux/timer.h

   1 #ifndef _LINUX_TIMER_H
   2 #define _LINUX_TIMER_H
   3
   4 #include <linux/list.h>
   5 #include <linux/ktime.h>
   6 #include <linux/spinlock.h>
   7 #include <linux/stddef.h>
   8
   9 struct tvec_t_base_s;
  10
  11 struct timer_list {
  12         struct list_head entry;
  13         unsigned long expires;
  14
  15         void (*function)(unsigned long);
  16         unsigned long data;
  17
  18         struct tvec_t_base_s *base;
  19 #ifdef CONFIG_TIMER_STATS
  20         void *start_site;
  21         char start_comm[16];
  22         int start_pid;
  23 #endif
  24 };
  25
  26 extern struct tvec_t_base_s boot_tvec_bases;
  27
  28 #define TIMER_INITIALIZER(_function, _expires, _data) {         \
  29                 .function = (_function),                        \
  30                 .expires = (_expires),                          \
  31                 .data = (_data),                                \
  32                 .base = &boot_tvec_bases,                       \
  33         }
  34
  35 #define DEFINE_TIMER(_name, _function, _expires, _data)         \
  36         struct timer_list _name =                               \
  37                 TIMER_INITIALIZER(_function, _expires, _data)
  38
  39 void fastcall init_timer(struct timer_list * timer);
  40 void fastcall init_timer_deferrable(struct timer_list *timer);
  41
  42 static inline void setup_timer(struct timer_list * timer,
  43                                 void (*function)(unsigned long),
  44                                 unsigned long data)
  45 {
  46         timer->function = function;
  47         timer->data = data;
  48         init_timer(timer);
  49 }
  50
  51 /**
  52  * timer_pending - is a timer pending?
  53  * @timer: the timer in question
  54  *
  55  * timer_pending will tell whether a given timer is currently pending,
  56  * or not. Callers must ensure serialization wrt. other operations done
  57  * to this timer, eg. interrupt contexts, or other CPUs on SMP.
  58  *
  59  * return value: 1 if the timer is pending, 0 if not.
  60  */
  61 static inline int timer_pending(const struct timer_list * timer)
  62 {
  63         return timer->entry.next != NULL;
  64 }
  65
  66 extern void add_timer_on(struct timer_list *timer, int cpu);
  67 extern int del_timer(struct timer_list * timer);
  68 extern int __mod_timer(struct timer_list *timer, unsigned long expires);
  69 extern int mod_timer(struct timer_list *timer, unsigned long expires);
  70
  71 /*
  72  * Return when the next timer-wheel timeout occurs (in absolute jiffies),
  73  * locks the timer base:
  74  */
  75 extern unsigned long next_timer_interrupt(void);
  76 /*
  77  * Return when the next timer-wheel timeout occurs (in absolute jiffies),
  78  * locks the timer base and does the comparison against the given
  79  * jiffie.
  80  */
  81 extern unsigned long get_next_timer_interrupt(unsigned long now);
  82
  83 /*
  84  * Timer-statistics info:
  85  */
  86 #ifdef CONFIG_TIMER_STATS
  87
  88 extern void init_timer_stats(void);
  89
  90 extern void timer_stats_update_stats(void *timer, pid_t pid, void *startf,
  91                                      void *timerf, char * comm);
  92
  93 static inline void timer_stats_account_timer(struct timer_list *timer)
  94 {
  95         timer_stats_update_stats(timer, timer->start_pid, timer->start_site,
  96                                  timer->function, timer->start_comm);
  97 }
  98
  99 extern void __timer_stats_timer_set_start_info(struct timer_list *timer,
 100                                                void *addr);
 101
 102 static inline void timer_stats_timer_set_start_info(struct timer_list *timer)
 103 {
 104         __timer_stats_timer_set_start_info(timer, __builtin_return_address(0));
 105 }
 106
 107 static inline void timer_stats_timer_clear_start_info(struct timer_list *timer)
 108 {
 109         timer->start_site = NULL;
 110 }
 111 #else
 112 static inline void init_timer_stats(void)
 113 {
 114 }
 115
 116 static inline void timer_stats_account_timer(struct timer_list *timer)
 117 {
 118 }
 119
 120 static inline void timer_stats_timer_set_start_info(struct timer_list *timer)
 121 {
 122 }
 123
 124 static inline void timer_stats_timer_clear_start_info(struct timer_list *timer)
 125 {
 126 }
 127 #endif
 128
 129 extern void delayed_work_timer_fn(unsigned long __data);
 130
 131 /**
 132  * add_timer - start a timer
 133  * @timer: the timer to be added
 134  *
 135  * The kernel will do a ->function(->data) callback from the
 136  * timer interrupt at the ->expires point in the future. The
 137  * current time is 'jiffies'.
 138  *
 139  * The timer's ->expires, ->function (and if the handler uses it, ->data)
 140  * fields must be set prior calling this function.
 141  *
 142  * Timers with an ->expires field in the past will be executed in the next
 143  * timer tick.
 144  */
 145 static inline void add_timer(struct timer_list *timer)
 146 {
 147         BUG_ON(timer_pending(timer));
 148         __mod_timer(timer, timer->expires);
 149 }
 150
 151 #ifdef CONFIG_SMP
 152   extern int try_to_del_timer_sync(struct timer_list *timer);
 153   extern int del_timer_sync(struct timer_list *timer);
 154 #else
 155 # define try_to_del_timer_sync(t)       del_timer(t)
 156 # define del_timer_sync(t)              del_timer(t)
 157 #endif
 158
 159 #define del_singleshot_timer_sync(t) del_timer_sync(t)
 160
 161 extern void init_timers(void);
 162 extern void run_local_timers(void);
 163 struct hrtimer;
 164 extern enum hrtimer_restart it_real_fn(struct hrtimer *);
 165
 166 unsigned long __round_jiffies(unsigned long j, int cpu);
 167 unsigned long __round_jiffies_relative(unsigned long j, int cpu);
 168 unsigned long round_jiffies(unsigned long j);
 169 unsigned long round_jiffies_relative(unsigned long j);
 170
 171
 172 #endif