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/stddef.h>
   7 #include <linux/debugobjects.h>
   8 #include <linux/stringify.h>
   9
  10 struct tvec_base;
  11
  12 struct timer_list {
  13         struct list_head entry;
  14         unsigned long expires;
  15
  16         void (*function)(unsigned long);
  17         unsigned long data;
  18
  19         struct tvec_base *base;
  20 #ifdef CONFIG_TIMER_STATS
  21         void *start_site;
  22         char start_comm[16];
  23         int start_pid;
  24 #endif
  25 #ifdef CONFIG_LOCKDEP
  26         struct lockdep_map lockdep_map;
  27 #endif
  28 };
  29
  30 extern struct tvec_base boot_tvec_bases;
  31
  32 #ifdef CONFIG_LOCKDEP
  33 /*
  34  * NB: because we have to copy the lockdep_map, setting the lockdep_map key
  35  * (second argument) here is required, otherwise it could be initialised to
  36  * the copy of the lockdep_map later! We use the pointer to and the string
  37  * "<file>:<line>" as the key resp. the name of the lockdep_map.
  38  */
  39 #define __TIMER_LOCKDEP_MAP_INITIALIZER(_kn)                            \
  40         .lockdep_map = STATIC_LOCKDEP_MAP_INIT(_kn, &_kn),
  41 #else
  42 #define __TIMER_LOCKDEP_MAP_INITIALIZER(_kn)
  43 #endif
  44
  45 #define TIMER_INITIALIZER(_function, _expires, _data) {         \
  46                 .entry = { .prev = TIMER_ENTRY_STATIC },        \
  47                 .function = (_function),                        \
  48                 .expires = (_expires),                          \
  49                 .data = (_data),                                \
  50                 .base = &boot_tvec_bases,                       \
  51                 __TIMER_LOCKDEP_MAP_INITIALIZER(                \
  52                         __FILE__ ":" __stringify(__LINE__))     \
  53         }
  54
  55 #define DEFINE_TIMER(_name, _function, _expires, _data)         \
  56         struct timer_list _name =                               \
  57                 TIMER_INITIALIZER(_function, _expires, _data)
  58
  59 void init_timer_key(struct timer_list *timer,
  60                     const char *name,
  61                     struct lock_class_key *key);
  62 void init_timer_deferrable_key(struct timer_list *timer,
  63                                const char *name,
  64                                struct lock_class_key *key);
  65
  66 #ifdef CONFIG_LOCKDEP
  67 #define init_timer(timer)                                               \
  68         do {                                                            \
  69                 static struct lock_class_key __key;                     \
  70                 init_timer_key((timer), #timer, &__key);                \
  71         } while (0)
  72
  73 #define init_timer_deferrable(timer)                                    \
  74         do {                                                            \
  75                 static struct lock_class_key __key;                     \
  76                 init_timer_deferrable_key((timer), #timer, &__key);     \
  77         } while (0)
  78
  79 #define init_timer_on_stack(timer)                                      \
  80         do {                                                            \
  81                 static struct lock_class_key __key;                     \
  82                 init_timer_on_stack_key((timer), #timer, &__key);       \
  83         } while (0)
  84
  85 #define setup_timer(timer, fn, data)                                    \
  86         do {                                                            \
  87                 static struct lock_class_key __key;                     \
  88                 setup_timer_key((timer), #timer, &__key, (fn), (data));\
  89         } while (0)
  90
  91 #define setup_timer_on_stack(timer, fn, data)                           \
  92         do {                                                            \
  93                 static struct lock_class_key __key;                     \
  94                 setup_timer_on_stack_key((timer), #timer, &__key,       \
  95                                          (fn), (data));                 \
  96         } while (0)
  97 #else
  98 #define init_timer(timer)\
  99         init_timer_key((timer), NULL, NULL)
 100 #define init_timer_deferrable(timer)\
 101         init_timer_deferrable_key((timer), NULL, NULL)
 102 #define init_timer_on_stack(timer)\
 103         init_timer_on_stack_key((timer), NULL, NULL)
 104 #define setup_timer(timer, fn, data)\
 105         setup_timer_key((timer), NULL, NULL, (fn), (data))
 106 #define setup_timer_on_stack(timer, fn, data)\
 107         setup_timer_on_stack_key((timer), NULL, NULL, (fn), (data))
 108 #endif
 109
 110 #ifdef CONFIG_DEBUG_OBJECTS_TIMERS
 111 extern void init_timer_on_stack_key(struct timer_list *timer,
 112                                     const char *name,
 113                                     struct lock_class_key *key);
 114 extern void destroy_timer_on_stack(struct timer_list *timer);
 115 #else
 116 static inline void destroy_timer_on_stack(struct timer_list *timer) { }
 117 static inline void init_timer_on_stack_key(struct timer_list *timer,
 118                                            const char *name,
 119                                            struct lock_class_key *key)
 120 {
 121         init_timer_key(timer, name, key);
 122 }
 123 #endif
 124
 125 static inline void setup_timer_key(struct timer_list * timer,
 126                                 const char *name,
 127                                 struct lock_class_key *key,
 128                                 void (*function)(unsigned long),
 129                                 unsigned long data)
 130 {
 131         timer->function = function;
 132         timer->data = data;
 133         init_timer_key(timer, name, key);
 134 }
 135
 136 static inline void setup_timer_on_stack_key(struct timer_list *timer,
 137                                         const char *name,
 138                                         struct lock_class_key *key,
 139                                         void (*function)(unsigned long),
 140                                         unsigned long data)
 141 {
 142         timer->function = function;
 143         timer->data = data;
 144         init_timer_on_stack_key(timer, name, key);
 145 }
 146
 147 /**
 148  * timer_pending - is a timer pending?
 149  * @timer: the timer in question
 150  *
 151  * timer_pending will tell whether a given timer is currently pending,
 152  * or not. Callers must ensure serialization wrt. other operations done
 153  * to this timer, eg. interrupt contexts, or other CPUs on SMP.
 154  *
 155  * return value: 1 if the timer is pending, 0 if not.
 156  */
 157 static inline int timer_pending(const struct timer_list * timer)
 158 {
 159         return timer->entry.next != NULL;
 160 }
 161
 162 extern void add_timer_on(struct timer_list *timer, int cpu);
 163 extern int del_timer(struct timer_list * timer);
 164 extern int mod_timer(struct timer_list *timer, unsigned long expires);
 165 extern int mod_timer_pending(struct timer_list *timer, unsigned long expires);
 166
 167 /*
 168  * The jiffies value which is added to now, when there is no timer
 169  * in the timer wheel:
 170  */
 171 #define NEXT_TIMER_MAX_DELTA    ((1UL << 30) - 1)
 172
 173 /*
 174  * Return when the next timer-wheel timeout occurs (in absolute jiffies),
 175  * locks the timer base:
 176  */
 177 extern unsigned long next_timer_interrupt(void);
 178 /*
 179  * Return when the next timer-wheel timeout occurs (in absolute jiffies),
 180  * locks the timer base and does the comparison against the given
 181  * jiffie.
 182  */
 183 extern unsigned long get_next_timer_interrupt(unsigned long now);
 184
 185 /*
 186  * Timer-statistics info:
 187  */
 188 #ifdef CONFIG_TIMER_STATS
 189
 190 #define TIMER_STATS_FLAG_DEFERRABLE     0x1
 191
 192 extern void init_timer_stats(void);
 193
 194 extern void timer_stats_update_stats(void *timer, pid_t pid, void *startf,
 195                                      void *timerf, char *comm,
 196                                      unsigned int timer_flag);
 197
 198 extern void __timer_stats_timer_set_start_info(struct timer_list *timer,
 199                                                void *addr);
 200
 201 static inline void timer_stats_timer_set_start_info(struct timer_list *timer)
 202 {
 203         __timer_stats_timer_set_start_info(timer, __builtin_return_address(0));
 204 }
 205
 206 static inline void timer_stats_timer_clear_start_info(struct timer_list *timer)
 207 {
 208         timer->start_site = NULL;
 209 }
 210 #else
 211 static inline void init_timer_stats(void)
 212 {
 213 }
 214
 215 static inline void timer_stats_timer_set_start_info(struct timer_list *timer)
 216 {
 217 }
 218
 219 static inline void timer_stats_timer_clear_start_info(struct timer_list *timer)
 220 {
 221 }
 222 #endif
 223
 224 extern void add_timer(struct timer_list *timer);
 225
 226 #ifdef CONFIG_SMP
 227   extern int try_to_del_timer_sync(struct timer_list *timer);
 228   extern int del_timer_sync(struct timer_list *timer);
 229 #else
 230 # define try_to_del_timer_sync(t)       del_timer(t)
 231 # define del_timer_sync(t)              del_timer(t)
 232 #endif
 233
 234 #define del_singleshot_timer_sync(t) del_timer_sync(t)
 235
 236 extern void init_timers(void);
 237 extern void run_local_timers(void);
 238 struct hrtimer;
 239 extern enum hrtimer_restart it_real_fn(struct hrtimer *);
 240
 241 unsigned long __round_jiffies(unsigned long j, int cpu);
 242 unsigned long __round_jiffies_relative(unsigned long j, int cpu);
 243 unsigned long round_jiffies(unsigned long j);
 244 unsigned long round_jiffies_relative(unsigned long j);
 245
 246 unsigned long __round_jiffies_up(unsigned long j, int cpu);
 247 unsigned long __round_jiffies_up_relative(unsigned long j, int cpu);
 248 unsigned long round_jiffies_up(unsigned long j);
 249 unsigned long round_jiffies_up_relative(unsigned long j);
 250
 251 #endif