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
44struct execute_work {
45 struct work_struct work;
46};
47
48#ifdef CONFIG_LOCKDEP
49/*
50 * NB: because we have to copy the lockdep_map, setting _key
51 * here is required, otherwise it could get initialised to the
52 * copy of the lockdep_map!
53 */
54#define __WORK_INIT_LOCKDEP_MAP(n, k) \
55 .lockdep_map = STATIC_LOCKDEP_MAP_INIT(n, k),
56#else
57#define __WORK_INIT_LOCKDEP_MAP(n, k)
58#endif
59
60#define __WORK_INITIALIZER(n, f) { \
61 .data = WORK_DATA_INIT(), \
62 .entry = { &(n).entry, &(n).entry }, \
63 .func = (f), \
64 __WORK_INIT_LOCKDEP_MAP(#n, &(n)) \
65 }
66
67#define __DELAYED_WORK_INITIALIZER(n, f) { \
68 .work = __WORK_INITIALIZER((n).work, (f)), \
69 .timer = TIMER_INITIALIZER(NULL, 0, 0), \
70 }
71
72#define DECLARE_WORK(n, f) \
73 struct work_struct n = __WORK_INITIALIZER(n, f)
74
75#define DECLARE_DELAYED_WORK(n, f) \
76 struct delayed_work n = __DELAYED_WORK_INITIALIZER(n, f)
77
78/*
79 * initialize a work item's function pointer
80 */
81#define PREPARE_WORK(_work, _func) \
82 do { \
83 (_work)->func = (_func); \
84 } while (0)
85
86#define PREPARE_DELAYED_WORK(_work, _func) \
87 PREPARE_WORK(&(_work)->work, (_func))
88
89/*
90 * initialize all of a work item in one go
91 *
92 * NOTE! No point in using "atomic_long_set()": useing a direct
93 * assignment of the work data initializer allows the compiler
94 * to generate better code.
95 */
96#ifdef CONFIG_LOCKDEP
97#define INIT_WORK(_work, _func) \
98 do { \
99 static struct lock_class_key __key; \
100 \
101 (_work)->data = (atomic_long_t) WORK_DATA_INIT(); \
102 lockdep_init_map(&(_work)->lockdep_map, #_work, &__key, 0);\
103 INIT_LIST_HEAD(&(_work)->entry); \
104 PREPARE_WORK((_work), (_func)); \
105 } while (0)
106#else
107#define INIT_WORK(_work, _func) \
108 do { \
109 (_work)->data = (atomic_long_t) WORK_DATA_INIT(); \
110 INIT_LIST_HEAD(&(_work)->entry); \
111 PREPARE_WORK((_work), (_func)); \
112 } while (0)
113#endif
114
115#define INIT_DELAYED_WORK(_work, _func) \
116 do { \
117 INIT_WORK(&(_work)->work, (_func)); \
118 init_timer(&(_work)->timer); \
119 } while (0)
120
121#define INIT_DELAYED_WORK_DEFERRABLE(_work, _func) \
122 do { \
123 INIT_WORK(&(_work)->work, (_func)); \
124 init_timer_deferrable(&(_work)->timer); \
125 } while (0)
126
127/**
128 * work_pending - Find out whether a work item is currently pending
129 * @work: The work item in question
130 */
131#define work_pending(work) \
132 test_bit(WORK_STRUCT_PENDING, work_data_bits(work))
133
134/**
135 * delayed_work_pending - Find out whether a delayable work item is currently
136 * pending
137 * @work: The work item in question
138 */
139#define delayed_work_pending(w) \
140 work_pending(&(w)->work)
141
142/**
143 * work_clear_pending - for internal use only, mark a work item as not pending
144 * @work: The work item in question
145 */
146#define work_clear_pending(work) \
147 clear_bit(WORK_STRUCT_PENDING, work_data_bits(work))
148
149
150extern struct workqueue_struct *
151__create_workqueue_key(const char *name, int singlethread,
152 int freezeable, struct lock_class_key *key,
153 const char *lock_name);
154
155#ifdef CONFIG_LOCKDEP
156#define __create_workqueue(name, singlethread, freezeable) \
157({ \
158 static struct lock_class_key __key; \
159 const char *__lock_name; \
160 \
161 if (__builtin_constant_p(name)) \
162 __lock_name = (name); \
163 else \
164 __lock_name = #name; \
165 \
166 __create_workqueue_key((name), (singlethread), \
167 (freezeable), &__key, \
168 __lock_name); \
169})
170#else
171#define __create_workqueue(name, singlethread, freezeable) \
172 __create_workqueue_key((name), (singlethread), (freezeable), NULL, NULL)
173#endif
174
175#define create_workqueue(name) __create_workqueue((name), 0, 0)
176#define create_freezeable_workqueue(name) __create_workqueue((name), 1, 1)
177#define create_singlethread_workqueue(name) __create_workqueue((name), 1, 0)
178
179extern void destroy_workqueue(struct workqueue_struct *wq);
180
181extern int queue_work(struct workqueue_struct *wq, struct work_struct *work);
182extern int queue_delayed_work(struct workqueue_struct *wq,
183 struct delayed_work *work, unsigned long delay);
184extern int queue_delayed_work_on(int cpu, struct workqueue_struct *wq,
185 struct delayed_work *work, unsigned long delay);
186
187extern void flush_workqueue(struct workqueue_struct *wq);
188extern void flush_scheduled_work(void);
189
190extern int schedule_work(struct work_struct *work);
191extern int schedule_delayed_work(struct delayed_work *work, unsigned long delay);
192extern int schedule_delayed_work_on(int cpu, struct delayed_work *work,
193 unsigned long delay);
194extern int schedule_on_each_cpu(work_func_t func);
195extern int current_is_keventd(void);
196extern int keventd_up(void);
197
198extern void init_workqueues(void);
199int execute_in_process_context(work_func_t fn, struct execute_work *);
200
201extern int cancel_work_sync(struct work_struct *work);
202
203/*
204 * Kill off a pending schedule_delayed_work(). Note that the work callback
205 * function may still be running on return from cancel_delayed_work(), unless
206 * it returns 1 and the work doesn't re-arm itself. Run flush_workqueue() or
207 * cancel_work_sync() to wait on it.
208 */
209static inline int cancel_delayed_work(struct delayed_work *work)
210{
211 int ret;
212
213 ret = del_timer_sync(&work->timer);
214 if (ret)
215 work_clear_pending(&work->work);
216 return ret;
217}
218
219extern int cancel_delayed_work_sync(struct delayed_work *work);
220
221/* Obsolete. use cancel_delayed_work_sync() */
222static inline
223void cancel_rearming_delayed_workqueue(struct workqueue_struct *wq,
224 struct delayed_work *work)
225{
226 cancel_delayed_work_sync(work);
227}
228
229/* Obsolete. use cancel_delayed_work_sync() */
230static inline
231void cancel_rearming_delayed_work(struct delayed_work *work)
232{
233 cancel_delayed_work_sync(work);
234}
235
236#endif