Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
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linux
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
8struct tvec_base;
9
10struct timer_list {
11 struct list_head entry;
12 unsigned long expires;
13
14 void (*function)(unsigned long);
15 unsigned long data;
16
17 struct tvec_base *base;
18#ifdef CONFIG_TIMER_STATS
19 void *start_site;
20 char start_comm[16];
21 int start_pid;
22#endif
23};
24
25extern struct tvec_base boot_tvec_bases;
26
27#define TIMER_INITIALIZER(_function, _expires, _data) { \
28 .function = (_function), \
29 .expires = (_expires), \
30 .data = (_data), \
31 .base = &boot_tvec_bases, \
32 }
33
34#define DEFINE_TIMER(_name, _function, _expires, _data) \
35 struct timer_list _name = \
36 TIMER_INITIALIZER(_function, _expires, _data)
37
38void init_timer(struct timer_list *timer);
39void init_timer_deferrable(struct timer_list *timer);
40
41static inline void setup_timer(struct timer_list * timer,
42 void (*function)(unsigned long),
43 unsigned long data)
44{
45 timer->function = function;
46 timer->data = data;
47 init_timer(timer);
48}
49
50/**
51 * timer_pending - is a timer pending?
52 * @timer: the timer in question
53 *
54 * timer_pending will tell whether a given timer is currently pending,
55 * or not. Callers must ensure serialization wrt. other operations done
56 * to this timer, eg. interrupt contexts, or other CPUs on SMP.
57 *
58 * return value: 1 if the timer is pending, 0 if not.
59 */
60static inline int timer_pending(const struct timer_list * timer)
61{
62 return timer->entry.next != NULL;
63}
64
65extern void add_timer_on(struct timer_list *timer, int cpu);
66extern int del_timer(struct timer_list * timer);
67extern int __mod_timer(struct timer_list *timer, unsigned long expires);
68extern int mod_timer(struct timer_list *timer, unsigned long expires);
69
70/*
71 * The jiffies value which is added to now, when there is no timer
72 * in the timer wheel:
73 */
74#define NEXT_TIMER_MAX_DELTA ((1UL << 30) - 1)
75
76/*
77 * Return when the next timer-wheel timeout occurs (in absolute jiffies),
78 * locks the timer base:
79 */
80extern unsigned long next_timer_interrupt(void);
81/*
82 * Return when the next timer-wheel timeout occurs (in absolute jiffies),
83 * locks the timer base and does the comparison against the given
84 * jiffie.
85 */
86extern unsigned long get_next_timer_interrupt(unsigned long now);
87
88/*
89 * Timer-statistics info:
90 */
91#ifdef CONFIG_TIMER_STATS
92
93#define TIMER_STATS_FLAG_DEFERRABLE 0x1
94
95extern void init_timer_stats(void);
96
97extern void timer_stats_update_stats(void *timer, pid_t pid, void *startf,
98 void *timerf, char *comm,
99 unsigned int timer_flag);
100
101extern void __timer_stats_timer_set_start_info(struct timer_list *timer,
102 void *addr);
103
104static inline void timer_stats_timer_set_start_info(struct timer_list *timer)
105{
106 __timer_stats_timer_set_start_info(timer, __builtin_return_address(0));
107}
108
109static inline void timer_stats_timer_clear_start_info(struct timer_list *timer)
110{
111 timer->start_site = NULL;
112}
113#else
114static inline void init_timer_stats(void)
115{
116}
117
118static inline void timer_stats_timer_set_start_info(struct timer_list *timer)
119{
120}
121
122static inline void timer_stats_timer_clear_start_info(struct timer_list *timer)
123{
124}
125#endif
126
127/**
128 * add_timer - start a timer
129 * @timer: the timer to be added
130 *
131 * The kernel will do a ->function(->data) callback from the
132 * timer interrupt at the ->expires point in the future. The
133 * current time is 'jiffies'.
134 *
135 * The timer's ->expires, ->function (and if the handler uses it, ->data)
136 * fields must be set prior calling this function.
137 *
138 * Timers with an ->expires field in the past will be executed in the next
139 * timer tick.
140 */
141static inline void add_timer(struct timer_list *timer)
142{
143 BUG_ON(timer_pending(timer));
144 __mod_timer(timer, timer->expires);
145}
146
147#ifdef CONFIG_SMP
148 extern int try_to_del_timer_sync(struct timer_list *timer);
149 extern int del_timer_sync(struct timer_list *timer);
150#else
151# define try_to_del_timer_sync(t) del_timer(t)
152# define del_timer_sync(t) del_timer(t)
153#endif
154
155#define del_singleshot_timer_sync(t) del_timer_sync(t)
156
157extern void init_timers(void);
158extern void run_local_timers(void);
159struct hrtimer;
160extern enum hrtimer_restart it_real_fn(struct hrtimer *);
161
162unsigned long __round_jiffies(unsigned long j, int cpu);
163unsigned long __round_jiffies_relative(unsigned long j, int cpu);
164unsigned long round_jiffies(unsigned long j);
165unsigned long round_jiffies_relative(unsigned long j);
166
167
168#endif