LXR linux/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
  10struct tvec_base;
  11
  12struct timer_list {
  13        /*
  14         * All fields that change during normal runtime grouped to the
  15         * same cacheline
  16         */
  17        struct list_head entry;
  18        unsigned long expires;
  19        struct tvec_base *base;
  20
  21        void (*function)(unsigned long);
  22        unsigned long data;
  23
  24        int slack;
  25
  26#ifdef CONFIG_TIMER_STATS
  27        void *start_site;
  28        char start_comm[16];
  29        int start_pid;
  30#endif
  31#ifdef CONFIG_LOCKDEP
  32        struct lockdep_map lockdep_map;
  33#endif
  34};
  35
  36extern struct tvec_base boot_tvec_bases;
  37
  38#ifdef CONFIG_LOCKDEP
  39/*
  40 * NB: because we have to copy the lockdep_map, setting the lockdep_map key
  41 * (second argument) here is required, otherwise it could be initialised to
  42 * the copy of the lockdep_map later! We use the pointer to and the string
  43 * "<file>:<line>" as the key resp. the name of the lockdep_map.
  44 */
  45#define __TIMER_LOCKDEP_MAP_INITIALIZER(_kn)                            \
  46        .lockdep_map = STATIC_LOCKDEP_MAP_INIT(_kn, &_kn),
  47#else
  48#define __TIMER_LOCKDEP_MAP_INITIALIZER(_kn)
  49#endif
  50
  51#define TIMER_INITIALIZER(_function, _expires, _data) {         \
  52                .entry = { .prev = TIMER_ENTRY_STATIC },        \
  53                .function = (_function),                        \
  54                .expires = (_expires),                          \
  55                .data = (_data),                                \
  56                .base = &boot_tvec_bases,                       \
  57                __TIMER_LOCKDEP_MAP_INITIALIZER(                \
  58                        __FILE__ ":" __stringify(__LINE__))     \
  59        }
  60
  61#define DEFINE_TIMER(_name, _function, _expires, _data)         \
  62        struct timer_list _name =                               \
  63                TIMER_INITIALIZER(_function, _expires, _data)
  64
  65void init_timer_key(struct timer_list *timer,
  66                    const char *name,
  67                    struct lock_class_key *key);
  68void init_timer_deferrable_key(struct timer_list *timer,
  69                               const char *name,
  70                               struct lock_class_key *key);
  71
  72#ifdef CONFIG_LOCKDEP
  73#define init_timer(timer)                                               \
  74        do {                                                            \
  75                static struct lock_class_key __key;                     \
  76                init_timer_key((timer), #timer, &__key);                \
  77        } while (0)
  78
  79#define init_timer_deferrable(timer)                                    \
  80        do {                                                            \
  81                static struct lock_class_key __key;                     \
  82                init_timer_deferrable_key((timer), #timer, &__key);     \
  83        } while (0)
  84
  85#define init_timer_on_stack(timer)                                      \
  86        do {                                                            \
  87                static struct lock_class_key __key;                     \
  88                init_timer_on_stack_key((timer), #timer, &__key);       \
  89        } while (0)
  90
  91#define setup_timer(timer, fn, data)                                    \
  92        do {                                                            \
  93                static struct lock_class_key __key;                     \
  94                setup_timer_key((timer), #timer, &__key, (fn), (data));\
  95        } while (0)
  96
  97#define setup_timer_on_stack(timer, fn, data)                           \
  98        do {                                                            \
  99                static struct lock_class_key __key;                     \
 100                setup_timer_on_stack_key((timer), #timer, &__key,       \
 101                                         (fn), (data));                 \
 102        } while (0)
 103#else
 104#define init_timer(timer)\
 105        init_timer_key((timer), NULL, NULL)
 106#define init_timer_deferrable(timer)\
 107        init_timer_deferrable_key((timer), NULL, NULL)
 108#define init_timer_on_stack(timer)\
 109        init_timer_on_stack_key((timer), NULL, NULL)
 110#define setup_timer(timer, fn, data)\
 111        setup_timer_key((timer), NULL, NULL, (fn), (data))
 112#define setup_timer_on_stack(timer, fn, data)\
 113        setup_timer_on_stack_key((timer), NULL, NULL, (fn), (data))
 114#endif
 115
 116#ifdef CONFIG_DEBUG_OBJECTS_TIMERS
 117extern void init_timer_on_stack_key(struct timer_list *timer,
 118                                    const char *name,
 119                                    struct lock_class_key *key);
 120extern void destroy_timer_on_stack(struct timer_list *timer);
 121#else
 122static inline void destroy_timer_on_stack(struct timer_list *timer) { }
 123static inline void init_timer_on_stack_key(struct timer_list *timer,
 124                                           const char *name,
 125                                           struct lock_class_key *key)
 126{
 127        init_timer_key(timer, name, key);
 128}
 129#endif
 130
 131static inline void setup_timer_key(struct timer_list * timer,
 132                                const char *name,
 133                                struct lock_class_key *key,
 134                                void (*function)(unsigned long),
 135                                unsigned long data)
 136{
 137        timer->function = function;
 138        timer->data = data;
 139        init_timer_key(timer, name, key);
 140}
 141
 142static inline void setup_timer_on_stack_key(struct timer_list *timer,
 143                                        const char *name,
 144                                        struct lock_class_key *key,
 145                                        void (*function)(unsigned long),
 146                                        unsigned long data)
 147{
 148        timer->function = function;
 149        timer->data = data;
 150        init_timer_on_stack_key(timer, name, key);
 151}
 152
 153/**
 154 * timer_pending - is a timer pending?
 155 * @timer: the timer in question
 156 *
 157 * timer_pending will tell whether a given timer is currently pending,
 158 * or not. Callers must ensure serialization wrt. other operations done
 159 * to this timer, eg. interrupt contexts, or other CPUs on SMP.
 160 *
 161 * return value: 1 if the timer is pending, 0 if not.
 162 */
 163static inline int timer_pending(const struct timer_list * timer)
 164{
 165        return timer->entry.next != NULL;
 166}
 167
 168extern void add_timer_on(struct timer_list *timer, int cpu);
 169extern int del_timer(struct timer_list * timer);
 170extern int mod_timer(struct timer_list *timer, unsigned long expires);
 171extern int mod_timer_pending(struct timer_list *timer, unsigned long expires);
 172extern int mod_timer_pinned(struct timer_list *timer, unsigned long expires);
 173
 174extern void set_timer_slack(struct timer_list *time, int slack_hz);
 175
 176#define TIMER_NOT_PINNED        0
 177#define TIMER_PINNED            1
 178/*
 179 * The jiffies value which is added to now, when there is no timer
 180 * in the timer wheel:
 181 */
 182#define NEXT_TIMER_MAX_DELTA    ((1UL << 30) - 1)
 183
 184/*
 185 * Return when the next timer-wheel timeout occurs (in absolute jiffies),
 186 * locks the timer base and does the comparison against the given
 187 * jiffie.
 188 */
 189extern unsigned long get_next_timer_interrupt(unsigned long now);
 190
 191/*
 192 * Timer-statistics info:
 193 */
 194#ifdef CONFIG_TIMER_STATS
 195
 196extern int timer_stats_active;
 197
 198#define TIMER_STATS_FLAG_DEFERRABLE     0x1
 199
 200extern void init_timer_stats(void);
 201
 202extern void timer_stats_update_stats(void *timer, pid_t pid, void *startf,
 203                                     void *timerf, char *comm,
 204                                     unsigned int timer_flag);
 205
 206extern void __timer_stats_timer_set_start_info(struct timer_list *timer,
 207                                               void *addr);
 208
 209static inline void timer_stats_timer_set_start_info(struct timer_list *timer)
 210{
 211        if (likely(!timer_stats_active))
 212                return;
 213        __timer_stats_timer_set_start_info(timer, __builtin_return_address(0));
 214}
 215
 216static inline void timer_stats_timer_clear_start_info(struct timer_list *timer)
 217{
 218        timer->start_site = NULL;
 219}
 220#else
 221static inline void init_timer_stats(void)
 222{
 223}
 224
 225static inline void timer_stats_timer_set_start_info(struct timer_list *timer)
 226{
 227}
 228
 229static inline void timer_stats_timer_clear_start_info(struct timer_list *timer)
 230{
 231}
 232#endif
 233
 234extern void add_timer(struct timer_list *timer);
 235
 236#ifdef CONFIG_SMP
 237  extern int try_to_del_timer_sync(struct timer_list *timer);
 238  extern int del_timer_sync(struct timer_list *timer);
 239#else
 240# define try_to_del_timer_sync(t)       del_timer(t)
 241# define del_timer_sync(t)              del_timer(t)
 242#endif
 243
 244#define del_singleshot_timer_sync(t) del_timer_sync(t)
 245
 246extern void init_timers(void);
 247extern void run_local_timers(void);
 248struct hrtimer;
 249extern enum hrtimer_restart it_real_fn(struct hrtimer *);
 250
 251unsigned long __round_jiffies(unsigned long j, int cpu);
 252unsigned long __round_jiffies_relative(unsigned long j, int cpu);
 253unsigned long round_jiffies(unsigned long j);
 254unsigned long round_jiffies_relative(unsigned long j);
 255
 256unsigned long __round_jiffies_up(unsigned long j, int cpu);
 257unsigned long __round_jiffies_up_relative(unsigned long j, int cpu);
 258unsigned long round_jiffies_up(unsigned long j);
 259unsigned long round_jiffies_up_relative(unsigned long j);
 260
 261#endif
 262