summaryrefslogtreecommitdiff
path: root/include/linux/workqueue.h
blob: 3cd51e579ab1c2cddd3960e1154b9c493794a85b (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
/*
 * workqueue.h --- work queue handling for Linux.
 */

#ifndef _LINUX_WORKQUEUE_H
#define _LINUX_WORKQUEUE_H

#include <linux/timer.h>
#include <linux/linkage.h>
#include <linux/bitops.h>
#include <linux/lockdep.h>
#include <asm/atomic.h>

struct workqueue_struct;

struct work_struct;
typedef void (*work_func_t)(struct work_struct *work);

/*
 * The first word is the work queue pointer and the flags rolled into
 * one
 */
#define work_data_bits(work) ((unsigned long *)(&(work)->data))

struct work_struct {
	atomic_long_t data;
#define WORK_STRUCT_PENDING 0		/* T if work item pending execution */
#define WORK_STRUCT_FLAG_MASK (3UL)
#define WORK_STRUCT_WQ_DATA_MASK (~WORK_STRUCT_FLAG_MASK)
	struct list_head entry;
	work_func_t func;
#ifdef CONFIG_LOCKDEP
	struct lockdep_map lockdep_map;
#endif
};

#define WORK_DATA_INIT()	ATOMIC_LONG_INIT(0)

struct delayed_work {
	struct work_struct work;
	struct timer_list timer;
};

struct execute_work {
	struct work_struct work;
};

#ifdef CONFIG_LOCKDEP
/*
 * NB: because we have to copy the lockdep_map, setting _key
 * here is required, otherwise it could get initialised to the
 * copy of the lockdep_map!
 */
#define __WORK_INIT_LOCKDEP_MAP(n, k) \
	.lockdep_map = STATIC_LOCKDEP_MAP_INIT(n, k),
#else
#define __WORK_INIT_LOCKDEP_MAP(n, k)
#endif

#define __WORK_INITIALIZER(n, f) {				\
	.data = WORK_DATA_INIT(),				\
	.entry	= { &(n).entry, &(n).entry },			\
	.func = (f),						\
	__WORK_INIT_LOCKDEP_MAP(#n, &(n))			\
	}

#define __DELAYED_WORK_INITIALIZER(n, f) {			\
	.work = __WORK_INITIALIZER((n).work, (f)),		\
	.timer = TIMER_INITIALIZER(NULL, 0, 0),			\
	}

#define DECLARE_WORK(n, f)					\
	struct work_struct n = __WORK_INITIALIZER(n, f)

#define DECLARE_DELAYED_WORK(n, f)				\
	struct delayed_work n = __DELAYED_WORK_INITIALIZER(n, f)

/*
 * initialize a work item's function pointer
 */
#define PREPARE_WORK(_work, _func)				\
	do {							\
		(_work)->func = (_func);			\
	} while (0)

#define PREPARE_DELAYED_WORK(_work, _func)			\
	PREPARE_WORK(&(_work)->work, (_func))

/*
 * initialize all of a work item in one go
 *
 * NOTE! No point in using "atomic_long_set()": useing a direct
 * assignment of the work data initializer allows the compiler
 * to generate better code.
 */
#ifdef CONFIG_LOCKDEP
#define INIT_WORK(_work, _func)						\
	do {								\
		static struct lock_class_key __key;			\
									\
		(_work)->data = (atomic_long_t) WORK_DATA_INIT();	\
		lockdep_init_map(&(_work)->lockdep_map, #_work, &__key, 0);\
		INIT_LIST_HEAD(&(_work)->entry);			\
		PREPARE_WORK((_work), (_func));				\
	} while (0)
#else
#define INIT_WORK(_work, _func)						\
	do {								\
		(_work)->data = (atomic_long_t) WORK_DATA_INIT();	\
		INIT_LIST_HEAD(&(_work)->entry);			\
		PREPARE_WORK((_work), (_func));				\
	} while (0)
#endif

#define INIT_DELAYED_WORK(_work, _func)				\
	do {							\
		INIT_WORK(&(_work)->work, (_func));		\
		init_timer(&(_work)->timer);			\
	} while (0)

#define INIT_DELAYED_WORK_ON_STACK(_work, _func)		\
	do {							\
		INIT_WORK(&(_work)->work, (_func));		\
		init_timer_on_stack(&(_work)->timer);		\
	} while (0)

#define INIT_DELAYED_WORK_DEFERRABLE(_work, _func)			\
	do {							\
		INIT_WORK(&(_work)->work, (_func));		\
		init_timer_deferrable(&(_work)->timer);		\
	} while (0)

#define INIT_DELAYED_WORK_ON_STACK(_work, _func)		\
	do {							\
		INIT_WORK(&(_work)->work, (_func));		\
		init_timer_on_stack(&(_work)->timer);		\
	} while (0)

/**
 * work_pending - Find out whether a work item is currently pending
 * @work: The work item in question
 */
#define work_pending(work) \
	test_bit(WORK_STRUCT_PENDING, work_data_bits(work))

/**
 * delayed_work_pending - Find out whether a delayable work item is currently
 * pending
 * @work: The work item in question
 */
#define delayed_work_pending(w) \
	work_pending(&(w)->work)

/**
 * work_clear_pending - for internal use only, mark a work item as not pending
 * @work: The work item in question
 */
#define work_clear_pending(work) \
	clear_bit(WORK_STRUCT_PENDING, work_data_bits(work))


extern struct workqueue_struct *
__create_workqueue_key(const char *name, int singlethread,
		       int freezeable, int rt, struct lock_class_key *key,
		       const char *lock_name);

#ifdef CONFIG_LOCKDEP
#define __create_workqueue(name, singlethread, freezeable, rt)	\
({								\
	static struct lock_class_key __key;			\
	const char *__lock_name;				\
								\
	if (__builtin_constant_p(name))				\
		__lock_name = (name);				\
	else							\
		__lock_name = #name;				\
								\
	__create_workqueue_key((name), (singlethread),		\
			       (freezeable), (rt), &__key,	\
			       __lock_name);			\
})
#else
#define __create_workqueue(name, singlethread, freezeable, rt)	\
	__create_workqueue_key((name), (singlethread), (freezeable), (rt), \
			       NULL, NULL)
#endif

#define create_workqueue(name) __create_workqueue((name), 0, 0, 0)
#define create_rt_workqueue(name) __create_workqueue((name), 0, 0, 1)
#define create_freezeable_workqueue(name) __create_workqueue((name), 1, 1, 0)
#define create_singlethread_workqueue(name) __create_workqueue((name), 1, 0, 0)

extern void destroy_workqueue(struct workqueue_struct *wq);

extern int queue_work(struct workqueue_struct *wq, struct work_struct *work);
extern int queue_work_on(int cpu, struct workqueue_struct *wq,
			struct work_struct *work);
extern int queue_delayed_work(struct workqueue_struct *wq,
			struct delayed_work *work, unsigned long delay);
extern int queue_delayed_work_on(int cpu, struct workqueue_struct *wq,
			struct delayed_work *work, unsigned long delay);

extern void flush_workqueue(struct workqueue_struct *wq);
extern void flush_scheduled_work(void);

extern int schedule_work(struct work_struct *work);
extern int schedule_work_on(int cpu, struct work_struct *work);
extern int schedule_delayed_work(struct delayed_work *work, unsigned long delay);
extern int schedule_delayed_work_on(int cpu, struct delayed_work *work,
					unsigned long delay);
extern int schedule_on_each_cpu(work_func_t func);
extern int current_is_keventd(void);
extern int keventd_up(void);

extern void init_workqueues(void);
int execute_in_process_context(work_func_t fn, struct execute_work *);

extern int flush_work(struct work_struct *work);

extern int cancel_work_sync(struct work_struct *work);

/*
 * Kill off a pending schedule_delayed_work().  Note that the work callback
 * function may still be running on return from cancel_delayed_work(), unless
 * it returns 1 and the work doesn't re-arm itself. Run flush_workqueue() or
 * cancel_work_sync() to wait on it.
 */
static inline int cancel_delayed_work(struct delayed_work *work)
{
	int ret;

	ret = del_timer_sync(&work->timer);
	if (ret)
		work_clear_pending(&work->work);
	return ret;
}

extern int cancel_delayed_work_sync(struct delayed_work *work);

/* Obsolete. use cancel_delayed_work_sync() */
static inline
void cancel_rearming_delayed_workqueue(struct workqueue_struct *wq,
					struct delayed_work *work)
{
	cancel_delayed_work_sync(work);
}

/* Obsolete. use cancel_delayed_work_sync() */
static inline
void cancel_rearming_delayed_work(struct delayed_work *work)
{
	cancel_delayed_work_sync(work);
}

#ifndef CONFIG_SMP
static inline long work_on_cpu(unsigned int cpu, long (*fn)(void *), void *arg)
{
	return fn(arg);
}
#else
long work_on_cpu(unsigned int cpu, long (*fn)(void *), void *arg);
#endif /* CONFIG_SMP */
#endif