Linux kernel mirror (for testing)
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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#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 hlist_node entry;
18 unsigned long expires;
19 void (*function)(unsigned long);
20 unsigned long data;
21 u32 flags;
22 int slack;
23
24#ifdef CONFIG_TIMER_STATS
25 int start_pid;
26 void *start_site;
27 char start_comm[16];
28#endif
29#ifdef CONFIG_LOCKDEP
30 struct lockdep_map lockdep_map;
31#endif
32};
33
34#ifdef CONFIG_LOCKDEP
35/*
36 * NB: because we have to copy the lockdep_map, setting the lockdep_map key
37 * (second argument) here is required, otherwise it could be initialised to
38 * the copy of the lockdep_map later! We use the pointer to and the string
39 * "<file>:<line>" as the key resp. the name of the lockdep_map.
40 */
41#define __TIMER_LOCKDEP_MAP_INITIALIZER(_kn) \
42 .lockdep_map = STATIC_LOCKDEP_MAP_INIT(_kn, &_kn),
43#else
44#define __TIMER_LOCKDEP_MAP_INITIALIZER(_kn)
45#endif
46
47/*
48 * A deferrable timer will work normally when the system is busy, but
49 * will not cause a CPU to come out of idle just to service it; instead,
50 * the timer will be serviced when the CPU eventually wakes up with a
51 * subsequent non-deferrable timer.
52 *
53 * An irqsafe timer is executed with IRQ disabled and it's safe to wait for
54 * the completion of the running instance from IRQ handlers, for example,
55 * by calling del_timer_sync().
56 *
57 * Note: The irq disabled callback execution is a special case for
58 * workqueue locking issues. It's not meant for executing random crap
59 * with interrupts disabled. Abuse is monitored!
60 */
61#define TIMER_CPUMASK 0x0007FFFF
62#define TIMER_MIGRATING 0x00080000
63#define TIMER_BASEMASK (TIMER_CPUMASK | TIMER_MIGRATING)
64#define TIMER_DEFERRABLE 0x00100000
65#define TIMER_IRQSAFE 0x00200000
66
67#define __TIMER_INITIALIZER(_function, _expires, _data, _flags) { \
68 .entry = { .next = TIMER_ENTRY_STATIC }, \
69 .function = (_function), \
70 .expires = (_expires), \
71 .data = (_data), \
72 .flags = (_flags), \
73 .slack = -1, \
74 __TIMER_LOCKDEP_MAP_INITIALIZER( \
75 __FILE__ ":" __stringify(__LINE__)) \
76 }
77
78#define TIMER_INITIALIZER(_function, _expires, _data) \
79 __TIMER_INITIALIZER((_function), (_expires), (_data), 0)
80
81#define TIMER_DEFERRED_INITIALIZER(_function, _expires, _data) \
82 __TIMER_INITIALIZER((_function), (_expires), (_data), TIMER_DEFERRABLE)
83
84#define DEFINE_TIMER(_name, _function, _expires, _data) \
85 struct timer_list _name = \
86 TIMER_INITIALIZER(_function, _expires, _data)
87
88void init_timer_key(struct timer_list *timer, unsigned int flags,
89 const char *name, struct lock_class_key *key);
90
91#ifdef CONFIG_DEBUG_OBJECTS_TIMERS
92extern void init_timer_on_stack_key(struct timer_list *timer,
93 unsigned int flags, const char *name,
94 struct lock_class_key *key);
95extern void destroy_timer_on_stack(struct timer_list *timer);
96#else
97static inline void destroy_timer_on_stack(struct timer_list *timer) { }
98static inline void init_timer_on_stack_key(struct timer_list *timer,
99 unsigned int flags, const char *name,
100 struct lock_class_key *key)
101{
102 init_timer_key(timer, flags, name, key);
103}
104#endif
105
106#ifdef CONFIG_LOCKDEP
107#define __init_timer(_timer, _flags) \
108 do { \
109 static struct lock_class_key __key; \
110 init_timer_key((_timer), (_flags), #_timer, &__key); \
111 } while (0)
112
113#define __init_timer_on_stack(_timer, _flags) \
114 do { \
115 static struct lock_class_key __key; \
116 init_timer_on_stack_key((_timer), (_flags), #_timer, &__key); \
117 } while (0)
118#else
119#define __init_timer(_timer, _flags) \
120 init_timer_key((_timer), (_flags), NULL, NULL)
121#define __init_timer_on_stack(_timer, _flags) \
122 init_timer_on_stack_key((_timer), (_flags), NULL, NULL)
123#endif
124
125#define init_timer(timer) \
126 __init_timer((timer), 0)
127#define init_timer_deferrable(timer) \
128 __init_timer((timer), TIMER_DEFERRABLE)
129#define init_timer_on_stack(timer) \
130 __init_timer_on_stack((timer), 0)
131
132#define __setup_timer(_timer, _fn, _data, _flags) \
133 do { \
134 __init_timer((_timer), (_flags)); \
135 (_timer)->function = (_fn); \
136 (_timer)->data = (_data); \
137 } while (0)
138
139#define __setup_timer_on_stack(_timer, _fn, _data, _flags) \
140 do { \
141 __init_timer_on_stack((_timer), (_flags)); \
142 (_timer)->function = (_fn); \
143 (_timer)->data = (_data); \
144 } while (0)
145
146#define setup_timer(timer, fn, data) \
147 __setup_timer((timer), (fn), (data), 0)
148#define setup_deferrable_timer(timer, fn, data) \
149 __setup_timer((timer), (fn), (data), TIMER_DEFERRABLE)
150#define setup_timer_on_stack(timer, fn, data) \
151 __setup_timer_on_stack((timer), (fn), (data), 0)
152#define setup_deferrable_timer_on_stack(timer, fn, data) \
153 __setup_timer_on_stack((timer), (fn), (data), TIMER_DEFERRABLE)
154
155/**
156 * timer_pending - is a timer pending?
157 * @timer: the timer in question
158 *
159 * timer_pending will tell whether a given timer is currently pending,
160 * or not. Callers must ensure serialization wrt. other operations done
161 * to this timer, eg. interrupt contexts, or other CPUs on SMP.
162 *
163 * return value: 1 if the timer is pending, 0 if not.
164 */
165static inline int timer_pending(const struct timer_list * timer)
166{
167 return timer->entry.pprev != NULL;
168}
169
170extern void add_timer_on(struct timer_list *timer, int cpu);
171extern int del_timer(struct timer_list * timer);
172extern int mod_timer(struct timer_list *timer, unsigned long expires);
173extern int mod_timer_pending(struct timer_list *timer, unsigned long expires);
174extern int mod_timer_pinned(struct timer_list *timer, unsigned long expires);
175
176extern void set_timer_slack(struct timer_list *time, int slack_hz);
177
178#define TIMER_NOT_PINNED 0
179#define TIMER_PINNED 1
180/*
181 * The jiffies value which is added to now, when there is no timer
182 * in the timer wheel:
183 */
184#define NEXT_TIMER_MAX_DELTA ((1UL << 30) - 1)
185
186/*
187 * Timer-statistics info:
188 */
189#ifdef CONFIG_TIMER_STATS
190
191extern int timer_stats_active;
192
193extern void init_timer_stats(void);
194
195extern void timer_stats_update_stats(void *timer, pid_t pid, void *startf,
196 void *timerf, char *comm, u32 flags);
197
198extern void __timer_stats_timer_set_start_info(struct timer_list *timer,
199 void *addr);
200
201static inline void timer_stats_timer_set_start_info(struct timer_list *timer)
202{
203 if (likely(!timer_stats_active))
204 return;
205 __timer_stats_timer_set_start_info(timer, __builtin_return_address(0));
206}
207
208static inline void timer_stats_timer_clear_start_info(struct timer_list *timer)
209{
210 timer->start_site = NULL;
211}
212#else
213static inline void init_timer_stats(void)
214{
215}
216
217static inline void timer_stats_timer_set_start_info(struct timer_list *timer)
218{
219}
220
221static inline void timer_stats_timer_clear_start_info(struct timer_list *timer)
222{
223}
224#endif
225
226extern void add_timer(struct timer_list *timer);
227
228extern int try_to_del_timer_sync(struct timer_list *timer);
229
230#ifdef CONFIG_SMP
231 extern int del_timer_sync(struct timer_list *timer);
232#else
233# define del_timer_sync(t) del_timer(t)
234#endif
235
236#define del_singleshot_timer_sync(t) del_timer_sync(t)
237
238extern void init_timers(void);
239extern void run_local_timers(void);
240struct hrtimer;
241extern enum hrtimer_restart it_real_fn(struct hrtimer *);
242
243#if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ_COMMON)
244#include <linux/sysctl.h>
245
246extern unsigned int sysctl_timer_migration;
247int timer_migration_handler(struct ctl_table *table, int write,
248 void __user *buffer, size_t *lenp,
249 loff_t *ppos);
250#endif
251
252unsigned long __round_jiffies(unsigned long j, int cpu);
253unsigned long __round_jiffies_relative(unsigned long j, int cpu);
254unsigned long round_jiffies(unsigned long j);
255unsigned long round_jiffies_relative(unsigned long j);
256
257unsigned long __round_jiffies_up(unsigned long j, int cpu);
258unsigned long __round_jiffies_up_relative(unsigned long j, int cpu);
259unsigned long round_jiffies_up(unsigned long j);
260unsigned long round_jiffies_up_relative(unsigned long j);
261
262#endif