Linux kernel mirror (for testing)
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linux
1/*
2 * workqueue.h --- work queue handling for Linux.
3 */
4
5#ifndef _LINUX_WORKQUEUE_H
6#define _LINUX_WORKQUEUE_H
7
8#include <linux/timer.h>
9#include <linux/linkage.h>
10#include <linux/bitops.h>
11#include <linux/lockdep.h>
12#include <asm/atomic.h>
13
14struct workqueue_struct;
15
16struct work_struct;
17typedef void (*work_func_t)(struct work_struct *work);
18
19/*
20 * The first word is the work queue pointer and the flags rolled into
21 * one
22 */
23#define work_data_bits(work) ((unsigned long *)(&(work)->data))
24
25struct work_struct {
26 atomic_long_t data;
27#define WORK_STRUCT_PENDING 0 /* T if work item pending execution */
28#define WORK_STRUCT_FLAG_MASK (3UL)
29#define WORK_STRUCT_WQ_DATA_MASK (~WORK_STRUCT_FLAG_MASK)
30 struct list_head entry;
31 work_func_t func;
32#ifdef CONFIG_LOCKDEP
33 struct lockdep_map lockdep_map;
34#endif
35};
36
37#define WORK_DATA_INIT() ATOMIC_LONG_INIT(0)
38
39struct delayed_work {
40 struct work_struct work;
41 struct timer_list timer;
42};
43
44static inline struct delayed_work *to_delayed_work(struct work_struct *work)
45{
46 return container_of(work, struct delayed_work, work);
47}
48
49struct execute_work {
50 struct work_struct work;
51};
52
53#ifdef CONFIG_LOCKDEP
54/*
55 * NB: because we have to copy the lockdep_map, setting _key
56 * here is required, otherwise it could get initialised to the
57 * copy of the lockdep_map!
58 */
59#define __WORK_INIT_LOCKDEP_MAP(n, k) \
60 .lockdep_map = STATIC_LOCKDEP_MAP_INIT(n, k),
61#else
62#define __WORK_INIT_LOCKDEP_MAP(n, k)
63#endif
64
65#define __WORK_INITIALIZER(n, f) { \
66 .data = WORK_DATA_INIT(), \
67 .entry = { &(n).entry, &(n).entry }, \
68 .func = (f), \
69 __WORK_INIT_LOCKDEP_MAP(#n, &(n)) \
70 }
71
72#define __DELAYED_WORK_INITIALIZER(n, f) { \
73 .work = __WORK_INITIALIZER((n).work, (f)), \
74 .timer = TIMER_INITIALIZER(NULL, 0, 0), \
75 }
76
77#define DECLARE_WORK(n, f) \
78 struct work_struct n = __WORK_INITIALIZER(n, f)
79
80#define DECLARE_DELAYED_WORK(n, f) \
81 struct delayed_work n = __DELAYED_WORK_INITIALIZER(n, f)
82
83/*
84 * initialize a work item's function pointer
85 */
86#define PREPARE_WORK(_work, _func) \
87 do { \
88 (_work)->func = (_func); \
89 } while (0)
90
91#define PREPARE_DELAYED_WORK(_work, _func) \
92 PREPARE_WORK(&(_work)->work, (_func))
93
94/*
95 * initialize all of a work item in one go
96 *
97 * NOTE! No point in using "atomic_long_set()": using a direct
98 * assignment of the work data initializer allows the compiler
99 * to generate better code.
100 */
101#ifdef CONFIG_LOCKDEP
102#define INIT_WORK(_work, _func) \
103 do { \
104 static struct lock_class_key __key; \
105 \
106 (_work)->data = (atomic_long_t) WORK_DATA_INIT(); \
107 lockdep_init_map(&(_work)->lockdep_map, #_work, &__key, 0);\
108 INIT_LIST_HEAD(&(_work)->entry); \
109 PREPARE_WORK((_work), (_func)); \
110 } while (0)
111#else
112#define INIT_WORK(_work, _func) \
113 do { \
114 (_work)->data = (atomic_long_t) WORK_DATA_INIT(); \
115 INIT_LIST_HEAD(&(_work)->entry); \
116 PREPARE_WORK((_work), (_func)); \
117 } while (0)
118#endif
119
120#define INIT_DELAYED_WORK(_work, _func) \
121 do { \
122 INIT_WORK(&(_work)->work, (_func)); \
123 init_timer(&(_work)->timer); \
124 } while (0)
125
126#define INIT_DELAYED_WORK_ON_STACK(_work, _func) \
127 do { \
128 INIT_WORK(&(_work)->work, (_func)); \
129 init_timer_on_stack(&(_work)->timer); \
130 } while (0)
131
132#define INIT_DELAYED_WORK_DEFERRABLE(_work, _func) \
133 do { \
134 INIT_WORK(&(_work)->work, (_func)); \
135 init_timer_deferrable(&(_work)->timer); \
136 } while (0)
137
138#define INIT_DELAYED_WORK_ON_STACK(_work, _func) \
139 do { \
140 INIT_WORK(&(_work)->work, (_func)); \
141 init_timer_on_stack(&(_work)->timer); \
142 } while (0)
143
144/**
145 * work_pending - Find out whether a work item is currently pending
146 * @work: The work item in question
147 */
148#define work_pending(work) \
149 test_bit(WORK_STRUCT_PENDING, work_data_bits(work))
150
151/**
152 * delayed_work_pending - Find out whether a delayable work item is currently
153 * pending
154 * @work: The work item in question
155 */
156#define delayed_work_pending(w) \
157 work_pending(&(w)->work)
158
159/**
160 * work_clear_pending - for internal use only, mark a work item as not pending
161 * @work: The work item in question
162 */
163#define work_clear_pending(work) \
164 clear_bit(WORK_STRUCT_PENDING, work_data_bits(work))
165
166
167extern struct workqueue_struct *
168__create_workqueue_key(const char *name, int singlethread,
169 int freezeable, int rt, struct lock_class_key *key,
170 const char *lock_name);
171
172#ifdef CONFIG_LOCKDEP
173#define __create_workqueue(name, singlethread, freezeable, rt) \
174({ \
175 static struct lock_class_key __key; \
176 const char *__lock_name; \
177 \
178 if (__builtin_constant_p(name)) \
179 __lock_name = (name); \
180 else \
181 __lock_name = #name; \
182 \
183 __create_workqueue_key((name), (singlethread), \
184 (freezeable), (rt), &__key, \
185 __lock_name); \
186})
187#else
188#define __create_workqueue(name, singlethread, freezeable, rt) \
189 __create_workqueue_key((name), (singlethread), (freezeable), (rt), \
190 NULL, NULL)
191#endif
192
193#define create_workqueue(name) __create_workqueue((name), 0, 0, 0)
194#define create_rt_workqueue(name) __create_workqueue((name), 0, 0, 1)
195#define create_freezeable_workqueue(name) __create_workqueue((name), 1, 1, 0)
196#define create_singlethread_workqueue(name) __create_workqueue((name), 1, 0, 0)
197
198extern void destroy_workqueue(struct workqueue_struct *wq);
199
200extern int queue_work(struct workqueue_struct *wq, struct work_struct *work);
201extern int queue_work_on(int cpu, struct workqueue_struct *wq,
202 struct work_struct *work);
203extern int queue_delayed_work(struct workqueue_struct *wq,
204 struct delayed_work *work, unsigned long delay);
205extern int queue_delayed_work_on(int cpu, struct workqueue_struct *wq,
206 struct delayed_work *work, unsigned long delay);
207
208extern void flush_workqueue(struct workqueue_struct *wq);
209extern void flush_scheduled_work(void);
210
211extern int schedule_work(struct work_struct *work);
212extern int schedule_work_on(int cpu, struct work_struct *work);
213extern int schedule_delayed_work(struct delayed_work *work, unsigned long delay);
214extern int schedule_delayed_work_on(int cpu, struct delayed_work *work,
215 unsigned long delay);
216extern int schedule_on_each_cpu(work_func_t func);
217extern int current_is_keventd(void);
218extern int keventd_up(void);
219
220extern void init_workqueues(void);
221int execute_in_process_context(work_func_t fn, struct execute_work *);
222
223extern int flush_work(struct work_struct *work);
224
225extern int cancel_work_sync(struct work_struct *work);
226
227/*
228 * Kill off a pending schedule_delayed_work(). Note that the work callback
229 * function may still be running on return from cancel_delayed_work(), unless
230 * it returns 1 and the work doesn't re-arm itself. Run flush_workqueue() or
231 * cancel_work_sync() to wait on it.
232 */
233static inline int cancel_delayed_work(struct delayed_work *work)
234{
235 int ret;
236
237 ret = del_timer_sync(&work->timer);
238 if (ret)
239 work_clear_pending(&work->work);
240 return ret;
241}
242
243/*
244 * Like above, but uses del_timer() instead of del_timer_sync(). This means,
245 * if it returns 0 the timer function may be running and the queueing is in
246 * progress.
247 */
248static inline int __cancel_delayed_work(struct delayed_work *work)
249{
250 int ret;
251
252 ret = del_timer(&work->timer);
253 if (ret)
254 work_clear_pending(&work->work);
255 return ret;
256}
257
258extern int cancel_delayed_work_sync(struct delayed_work *work);
259
260/* Obsolete. use cancel_delayed_work_sync() */
261static inline
262void cancel_rearming_delayed_workqueue(struct workqueue_struct *wq,
263 struct delayed_work *work)
264{
265 cancel_delayed_work_sync(work);
266}
267
268/* Obsolete. use cancel_delayed_work_sync() */
269static inline
270void cancel_rearming_delayed_work(struct delayed_work *work)
271{
272 cancel_delayed_work_sync(work);
273}
274
275#ifndef CONFIG_SMP
276static inline long work_on_cpu(unsigned int cpu, long (*fn)(void *), void *arg)
277{
278 return fn(arg);
279}
280#else
281long work_on_cpu(unsigned int cpu, long (*fn)(void *), void *arg);
282#endif /* CONFIG_SMP */
283#endif