ssb: remove the ssb DMA API
[linux-2.6.git] / include / linux / workqueue.h
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
14 struct workqueue_struct;
15
16 struct work_struct;
17 typedef 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
25 struct work_struct {
26         atomic_long_t data;
27 #define WORK_STRUCT_PENDING 0           /* T if work item pending execution */
28 #define WORK_STRUCT_STATIC  1           /* static initializer (debugobjects) */
29 #define WORK_STRUCT_FLAG_MASK (3UL)
30 #define WORK_STRUCT_WQ_DATA_MASK (~WORK_STRUCT_FLAG_MASK)
31         struct list_head entry;
32         work_func_t func;
33 #ifdef CONFIG_LOCKDEP
34         struct lockdep_map lockdep_map;
35 #endif
36 };
37
38 #define WORK_DATA_INIT()        ATOMIC_LONG_INIT(0)
39 #define WORK_DATA_STATIC_INIT() ATOMIC_LONG_INIT(2)
40
41 struct delayed_work {
42         struct work_struct work;
43         struct timer_list timer;
44 };
45
46 static inline struct delayed_work *to_delayed_work(struct work_struct *work)
47 {
48         return container_of(work, struct delayed_work, work);
49 }
50
51 struct execute_work {
52         struct work_struct work;
53 };
54
55 #ifdef CONFIG_LOCKDEP
56 /*
57  * NB: because we have to copy the lockdep_map, setting _key
58  * here is required, otherwise it could get initialised to the
59  * copy of the lockdep_map!
60  */
61 #define __WORK_INIT_LOCKDEP_MAP(n, k) \
62         .lockdep_map = STATIC_LOCKDEP_MAP_INIT(n, k),
63 #else
64 #define __WORK_INIT_LOCKDEP_MAP(n, k)
65 #endif
66
67 #define __WORK_INITIALIZER(n, f) {                              \
68         .data = WORK_DATA_STATIC_INIT(),                        \
69         .entry  = { &(n).entry, &(n).entry },                   \
70         .func = (f),                                            \
71         __WORK_INIT_LOCKDEP_MAP(#n, &(n))                       \
72         }
73
74 #define __DELAYED_WORK_INITIALIZER(n, f) {                      \
75         .work = __WORK_INITIALIZER((n).work, (f)),              \
76         .timer = TIMER_INITIALIZER(NULL, 0, 0),                 \
77         }
78
79 #define DECLARE_WORK(n, f)                                      \
80         struct work_struct n = __WORK_INITIALIZER(n, f)
81
82 #define DECLARE_DELAYED_WORK(n, f)                              \
83         struct delayed_work n = __DELAYED_WORK_INITIALIZER(n, f)
84
85 /*
86  * initialize a work item's function pointer
87  */
88 #define PREPARE_WORK(_work, _func)                              \
89         do {                                                    \
90                 (_work)->func = (_func);                        \
91         } while (0)
92
93 #define PREPARE_DELAYED_WORK(_work, _func)                      \
94         PREPARE_WORK(&(_work)->work, (_func))
95
96 #ifdef CONFIG_DEBUG_OBJECTS_WORK
97 extern void __init_work(struct work_struct *work, int onstack);
98 extern void destroy_work_on_stack(struct work_struct *work);
99 #else
100 static inline void __init_work(struct work_struct *work, int onstack) { }
101 static inline void destroy_work_on_stack(struct work_struct *work) { }
102 #endif
103
104 /*
105  * initialize all of a work item in one go
106  *
107  * NOTE! No point in using "atomic_long_set()": using a direct
108  * assignment of the work data initializer allows the compiler
109  * to generate better code.
110  */
111 #ifdef CONFIG_LOCKDEP
112 #define __INIT_WORK(_work, _func, _onstack)                             \
113         do {                                                            \
114                 static struct lock_class_key __key;                     \
115                                                                         \
116                 __init_work((_work), _onstack);                         \
117                 (_work)->data = (atomic_long_t) WORK_DATA_INIT();       \
118                 lockdep_init_map(&(_work)->lockdep_map, #_work, &__key, 0);\
119                 INIT_LIST_HEAD(&(_work)->entry);                        \
120                 PREPARE_WORK((_work), (_func));                         \
121         } while (0)
122 #else
123 #define __INIT_WORK(_work, _func, _onstack)                             \
124         do {                                                            \
125                 __init_work((_work), _onstack);                         \
126                 (_work)->data = (atomic_long_t) WORK_DATA_INIT();       \
127                 INIT_LIST_HEAD(&(_work)->entry);                        \
128                 PREPARE_WORK((_work), (_func));                         \
129         } while (0)
130 #endif
131
132 #define INIT_WORK(_work, _func)                                 \
133         do {                                                    \
134                 __INIT_WORK((_work), (_func), 0);               \
135         } while (0)
136
137 #define INIT_WORK_ON_STACK(_work, _func)                        \
138         do {                                                    \
139                 __INIT_WORK((_work), (_func), 1);               \
140         } while (0)
141
142 #define INIT_DELAYED_WORK(_work, _func)                         \
143         do {                                                    \
144                 INIT_WORK(&(_work)->work, (_func));             \
145                 init_timer(&(_work)->timer);                    \
146         } while (0)
147
148 #define INIT_DELAYED_WORK_ON_STACK(_work, _func)                \
149         do {                                                    \
150                 INIT_WORK_ON_STACK(&(_work)->work, (_func));    \
151                 init_timer_on_stack(&(_work)->timer);           \
152         } while (0)
153
154 #define INIT_DELAYED_WORK_DEFERRABLE(_work, _func)              \
155         do {                                                    \
156                 INIT_WORK(&(_work)->work, (_func));             \
157                 init_timer_deferrable(&(_work)->timer);         \
158         } while (0)
159
160 /**
161  * work_pending - Find out whether a work item is currently pending
162  * @work: The work item in question
163  */
164 #define work_pending(work) \
165         test_bit(WORK_STRUCT_PENDING, work_data_bits(work))
166
167 /**
168  * delayed_work_pending - Find out whether a delayable work item is currently
169  * pending
170  * @work: The work item in question
171  */
172 #define delayed_work_pending(w) \
173         work_pending(&(w)->work)
174
175 /**
176  * work_clear_pending - for internal use only, mark a work item as not pending
177  * @work: The work item in question
178  */
179 #define work_clear_pending(work) \
180         clear_bit(WORK_STRUCT_PENDING, work_data_bits(work))
181
182
183 extern struct workqueue_struct *
184 __create_workqueue_key(const char *name, int singlethread,
185                        int freezeable, int rt, struct lock_class_key *key,
186                        const char *lock_name);
187
188 #ifdef CONFIG_LOCKDEP
189 #define __create_workqueue(name, singlethread, freezeable, rt)  \
190 ({                                                              \
191         static struct lock_class_key __key;                     \
192         const char *__lock_name;                                \
193                                                                 \
194         if (__builtin_constant_p(name))                         \
195                 __lock_name = (name);                           \
196         else                                                    \
197                 __lock_name = #name;                            \
198                                                                 \
199         __create_workqueue_key((name), (singlethread),          \
200                                (freezeable), (rt), &__key,      \
201                                __lock_name);                    \
202 })
203 #else
204 #define __create_workqueue(name, singlethread, freezeable, rt)  \
205         __create_workqueue_key((name), (singlethread), (freezeable), (rt), \
206                                NULL, NULL)
207 #endif
208
209 #define create_workqueue(name) __create_workqueue((name), 0, 0, 0)
210 #define create_rt_workqueue(name) __create_workqueue((name), 0, 0, 1)
211 #define create_freezeable_workqueue(name) __create_workqueue((name), 1, 1, 0)
212 #define create_singlethread_workqueue(name) __create_workqueue((name), 1, 0, 0)
213
214 extern void destroy_workqueue(struct workqueue_struct *wq);
215
216 extern int queue_work(struct workqueue_struct *wq, struct work_struct *work);
217 extern int queue_work_on(int cpu, struct workqueue_struct *wq,
218                         struct work_struct *work);
219 extern int queue_delayed_work(struct workqueue_struct *wq,
220                         struct delayed_work *work, unsigned long delay);
221 extern int queue_delayed_work_on(int cpu, struct workqueue_struct *wq,
222                         struct delayed_work *work, unsigned long delay);
223
224 extern void flush_workqueue(struct workqueue_struct *wq);
225 extern void flush_scheduled_work(void);
226 extern void flush_delayed_work(struct delayed_work *work);
227
228 extern int schedule_work(struct work_struct *work);
229 extern int schedule_work_on(int cpu, struct work_struct *work);
230 extern int schedule_delayed_work(struct delayed_work *work, unsigned long delay);
231 extern int schedule_delayed_work_on(int cpu, struct delayed_work *work,
232                                         unsigned long delay);
233 extern int schedule_on_each_cpu(work_func_t func);
234 extern int current_is_keventd(void);
235 extern int keventd_up(void);
236
237 extern void init_workqueues(void);
238 int execute_in_process_context(work_func_t fn, struct execute_work *);
239
240 extern int flush_work(struct work_struct *work);
241
242 extern int cancel_work_sync(struct work_struct *work);
243
244 /*
245  * Kill off a pending schedule_delayed_work().  Note that the work callback
246  * function may still be running on return from cancel_delayed_work(), unless
247  * it returns 1 and the work doesn't re-arm itself. Run flush_workqueue() or
248  * cancel_work_sync() to wait on it.
249  */
250 static inline int cancel_delayed_work(struct delayed_work *work)
251 {
252         int ret;
253
254         ret = del_timer_sync(&work->timer);
255         if (ret)
256                 work_clear_pending(&work->work);
257         return ret;
258 }
259
260 /*
261  * Like above, but uses del_timer() instead of del_timer_sync(). This means,
262  * if it returns 0 the timer function may be running and the queueing is in
263  * progress.
264  */
265 static inline int __cancel_delayed_work(struct delayed_work *work)
266 {
267         int ret;
268
269         ret = del_timer(&work->timer);
270         if (ret)
271                 work_clear_pending(&work->work);
272         return ret;
273 }
274
275 extern int cancel_delayed_work_sync(struct delayed_work *work);
276
277 /* Obsolete. use cancel_delayed_work_sync() */
278 static inline
279 void cancel_rearming_delayed_workqueue(struct workqueue_struct *wq,
280                                         struct delayed_work *work)
281 {
282         cancel_delayed_work_sync(work);
283 }
284
285 /* Obsolete. use cancel_delayed_work_sync() */
286 static inline
287 void cancel_rearming_delayed_work(struct delayed_work *work)
288 {
289         cancel_delayed_work_sync(work);
290 }
291
292 #ifndef CONFIG_SMP
293 static inline long work_on_cpu(unsigned int cpu, long (*fn)(void *), void *arg)
294 {
295         return fn(arg);
296 }
297 #else
298 long work_on_cpu(unsigned int cpu, long (*fn)(void *), void *arg);
299 #endif /* CONFIG_SMP */
300 #endif