projects/linux·blob 243bfd2c · refs

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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
23#ifdef CONFIG_LOCKDEP
24 struct lockdep_map lockdep_map;
25#endif
26};
27
28#ifdef CONFIG_LOCKDEP
29/*
30 * NB: because we have to copy the lockdep_map, setting the lockdep_map key
31 * (second argument) here is required, otherwise it could be initialised to
32 * the copy of the lockdep_map later! We use the pointer to and the string
33 * "<file>:<line>" as the key resp. the name of the lockdep_map.
34 */
35#define __TIMER_LOCKDEP_MAP_INITIALIZER(_kn) \
36 .lockdep_map = STATIC_LOCKDEP_MAP_INIT(_kn, &_kn),
37#else
38#define __TIMER_LOCKDEP_MAP_INITIALIZER(_kn)
39#endif
40
41/*
42 * A deferrable timer will work normally when the system is busy, but
43 * will not cause a CPU to come out of idle just to service it; instead,
44 * the timer will be serviced when the CPU eventually wakes up with a
45 * subsequent non-deferrable timer.
46 *
47 * An irqsafe timer is executed with IRQ disabled and it's safe to wait for
48 * the completion of the running instance from IRQ handlers, for example,
49 * by calling del_timer_sync().
50 *
51 * Note: The irq disabled callback execution is a special case for
52 * workqueue locking issues. It's not meant for executing random crap
53 * with interrupts disabled. Abuse is monitored!
54 */
55#define TIMER_CPUMASK 0x0003FFFF
56#define TIMER_MIGRATING 0x00040000
57#define TIMER_BASEMASK (TIMER_CPUMASK | TIMER_MIGRATING)
58#define TIMER_DEFERRABLE 0x00080000
59#define TIMER_PINNED 0x00100000
60#define TIMER_IRQSAFE 0x00200000
61#define TIMER_ARRAYSHIFT 22
62#define TIMER_ARRAYMASK 0xFFC00000
63
64#define TIMER_TRACE_FLAGMASK (TIMER_MIGRATING | TIMER_DEFERRABLE | TIMER_PINNED | TIMER_IRQSAFE)
65
66#define __TIMER_INITIALIZER(_function, _expires, _data, _flags) { \
67 .entry = { .next = TIMER_ENTRY_STATIC }, \
68 .function = (_function), \
69 .expires = (_expires), \
70 .data = (_data), \
71 .flags = (_flags), \
72 __TIMER_LOCKDEP_MAP_INITIALIZER( \
73 __FILE__ ":" __stringify(__LINE__)) \
74 }
75
76#define TIMER_INITIALIZER(_function, _expires, _data) \
77 __TIMER_INITIALIZER((_function), (_expires), (_data), 0)
78
79#define TIMER_PINNED_INITIALIZER(_function, _expires, _data) \
80 __TIMER_INITIALIZER((_function), (_expires), (_data), TIMER_PINNED)
81
82#define TIMER_DEFERRED_INITIALIZER(_function, _expires, _data) \
83 __TIMER_INITIALIZER((_function), (_expires), (_data), TIMER_DEFERRABLE)
84
85#define TIMER_PINNED_DEFERRED_INITIALIZER(_function, _expires, _data) \
86 __TIMER_INITIALIZER((_function), (_expires), (_data), TIMER_DEFERRABLE | TIMER_PINNED)
87
88#define DEFINE_TIMER(_name, _function, _expires, _data) \
89 struct timer_list _name = \
90 TIMER_INITIALIZER(_function, _expires, _data)
91
92void init_timer_key(struct timer_list *timer, unsigned int flags,
93 const char *name, struct lock_class_key *key);
94
95#ifdef CONFIG_DEBUG_OBJECTS_TIMERS
96extern void init_timer_on_stack_key(struct timer_list *timer,
97 unsigned int flags, const char *name,
98 struct lock_class_key *key);
99extern void destroy_timer_on_stack(struct timer_list *timer);
100#else
101static inline void destroy_timer_on_stack(struct timer_list *timer) { }
102static inline void init_timer_on_stack_key(struct timer_list *timer,
103 unsigned int flags, const char *name,
104 struct lock_class_key *key)
105{
106 init_timer_key(timer, flags, name, key);
107}
108#endif
109
110#ifdef CONFIG_LOCKDEP
111#define __init_timer(_timer, _flags) \
112 do { \
113 static struct lock_class_key __key; \
114 init_timer_key((_timer), (_flags), #_timer, &__key); \
115 } while (0)
116
117#define __init_timer_on_stack(_timer, _flags) \
118 do { \
119 static struct lock_class_key __key; \
120 init_timer_on_stack_key((_timer), (_flags), #_timer, &__key); \
121 } while (0)
122#else
123#define __init_timer(_timer, _flags) \
124 init_timer_key((_timer), (_flags), NULL, NULL)
125#define __init_timer_on_stack(_timer, _flags) \
126 init_timer_on_stack_key((_timer), (_flags), NULL, NULL)
127#endif
128
129#define init_timer(timer) \
130 __init_timer((timer), 0)
131#define init_timer_pinned(timer) \
132 __init_timer((timer), TIMER_PINNED)
133#define init_timer_deferrable(timer) \
134 __init_timer((timer), TIMER_DEFERRABLE)
135#define init_timer_pinned_deferrable(timer) \
136 __init_timer((timer), TIMER_DEFERRABLE | TIMER_PINNED)
137#define init_timer_on_stack(timer) \
138 __init_timer_on_stack((timer), 0)
139
140#define __setup_timer(_timer, _fn, _data, _flags) \
141 do { \
142 __init_timer((_timer), (_flags)); \
143 (_timer)->function = (_fn); \
144 (_timer)->data = (_data); \
145 } while (0)
146
147#define __setup_timer_on_stack(_timer, _fn, _data, _flags) \
148 do { \
149 __init_timer_on_stack((_timer), (_flags)); \
150 (_timer)->function = (_fn); \
151 (_timer)->data = (_data); \
152 } while (0)
153
154#define setup_timer(timer, fn, data) \
155 __setup_timer((timer), (fn), (data), 0)
156#define setup_pinned_timer(timer, fn, data) \
157 __setup_timer((timer), (fn), (data), TIMER_PINNED)
158#define setup_deferrable_timer(timer, fn, data) \
159 __setup_timer((timer), (fn), (data), TIMER_DEFERRABLE)
160#define setup_pinned_deferrable_timer(timer, fn, data) \
161 __setup_timer((timer), (fn), (data), TIMER_DEFERRABLE | TIMER_PINNED)
162#define setup_timer_on_stack(timer, fn, data) \
163 __setup_timer_on_stack((timer), (fn), (data), 0)
164#define setup_pinned_timer_on_stack(timer, fn, data) \
165 __setup_timer_on_stack((timer), (fn), (data), TIMER_PINNED)
166#define setup_deferrable_timer_on_stack(timer, fn, data) \
167 __setup_timer_on_stack((timer), (fn), (data), TIMER_DEFERRABLE)
168#define setup_pinned_deferrable_timer_on_stack(timer, fn, data) \
169 __setup_timer_on_stack((timer), (fn), (data), TIMER_DEFERRABLE | TIMER_PINNED)
170
171/**
172 * timer_pending - is a timer pending?
173 * @timer: the timer in question
174 *
175 * timer_pending will tell whether a given timer is currently pending,
176 * or not. Callers must ensure serialization wrt. other operations done
177 * to this timer, eg. interrupt contexts, or other CPUs on SMP.
178 *
179 * return value: 1 if the timer is pending, 0 if not.
180 */
181static inline int timer_pending(const struct timer_list * timer)
182{
183 return timer->entry.pprev != NULL;
184}
185
186extern void add_timer_on(struct timer_list *timer, int cpu);
187extern int del_timer(struct timer_list * timer);
188extern int mod_timer(struct timer_list *timer, unsigned long expires);
189extern int mod_timer_pending(struct timer_list *timer, unsigned long expires);
190
191/*
192 * The jiffies value which is added to now, when there is no timer
193 * in the timer wheel:
194 */
195#define NEXT_TIMER_MAX_DELTA ((1UL << 30) - 1)
196
197extern void add_timer(struct timer_list *timer);
198
199extern int try_to_del_timer_sync(struct timer_list *timer);
200
201#ifdef CONFIG_SMP
202 extern int del_timer_sync(struct timer_list *timer);
203#else
204# define del_timer_sync(t) del_timer(t)
205#endif
206
207#define del_singleshot_timer_sync(t) del_timer_sync(t)
208
209extern void init_timers(void);
210extern void run_local_timers(void);
211struct hrtimer;
212extern enum hrtimer_restart it_real_fn(struct hrtimer *);
213
214#if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ_COMMON)
215struct ctl_table;
216
217extern unsigned int sysctl_timer_migration;
218int timer_migration_handler(struct ctl_table *table, int write,
219 void __user *buffer, size_t *lenp,
220 loff_t *ppos);
221#endif
222
223unsigned long __round_jiffies(unsigned long j, int cpu);
224unsigned long __round_jiffies_relative(unsigned long j, int cpu);
225unsigned long round_jiffies(unsigned long j);
226unsigned long round_jiffies_relative(unsigned long j);
227
228unsigned long __round_jiffies_up(unsigned long j, int cpu);
229unsigned long __round_jiffies_up_relative(unsigned long j, int cpu);
230unsigned long round_jiffies_up(unsigned long j);
231unsigned long round_jiffies_up_relative(unsigned long j);
232
233#ifdef CONFIG_HOTPLUG_CPU
234int timers_dead_cpu(unsigned int cpu);
235#else
236#define timers_dead_cpu NULL
237#endif
238
239#endif