[net-next-2.6.git] / include / linux / workqueue.h

/*
 * 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_STATIC  1		/* static initializer (debugobjects) */
#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)
#define WORK_DATA_STATIC_INIT()	ATOMIC_LONG_INIT(2)

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

static inline struct delayed_work *to_delayed_work(struct work_struct *work)
{
	return container_of(work, struct delayed_work, work);
}

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_STATIC_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))

#ifdef CONFIG_DEBUG_OBJECTS_WORK
extern void __init_work(struct work_struct *work, int onstack);
extern void destroy_work_on_stack(struct work_struct *work);
static inline unsigned int work_static(struct work_struct *work)
{
	return *work_data_bits(work) & (1 << WORK_STRUCT_STATIC);
}
#else
static inline void __init_work(struct work_struct *work, int onstack) { }
static inline void destroy_work_on_stack(struct work_struct *work) { }
static inline unsigned int work_static(struct work_struct *work) { return 0; }
#endif

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

#define INIT_WORK(_work, _func)					\
	do {							\
		__INIT_WORK((_work), (_func), 0);		\
	} while (0)

#define INIT_WORK_ON_STACK(_work, _func)			\
	do {							\
		__INIT_WORK((_work), (_func), 1);		\
	} while (0)

#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_ON_STACK(&(_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)

/**
 * 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,
		       struct lock_class_key *key, const char *lock_name);

#ifdef CONFIG_LOCKDEP
#define __create_workqueue(name, singlethread, freezeable)	\
({								\
	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), &__key,		\
			       __lock_name);			\
})
#else
#define __create_workqueue(name, singlethread, freezeable)	\
	__create_workqueue_key((name), (singlethread), (freezeable), \
			       NULL, NULL)
#endif

#define create_workqueue(name) __create_workqueue((name), 0, 0)
#define create_freezeable_workqueue(name) __create_workqueue((name), 1, 1)
#define create_singlethread_workqueue(name) __create_workqueue((name), 1, 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 void flush_delayed_work(struct delayed_work *work);

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;
}

/*
 * Like above, but uses del_timer() instead of del_timer_sync(). This means,
 * if it returns 0 the timer function may be running and the queueing is in
 * progress.
 */
static inline int __cancel_delayed_work(struct delayed_work *work)
{
	int ret;

	ret = del_timer(&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
Commit	Line	Data
1da177e4 LT	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>
4e6045f1	11	#include <linux/lockdep.h>
a08727ba	12	#include <asm/atomic.h>
1da177e4 LT	13
	14	struct workqueue_struct;
	15
65f27f38 DH	16	struct work_struct;
65f27f38 DH	17	typedef void (work_func_t)(struct work_struct work);
6bb49e59	18
a08727ba LT	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
1da177e4	25	struct work_struct {
a08727ba	26	atomic_long_t data;
365970a1	27	#define WORK_STRUCT_PENDING 0 /* T if work item pending execution */
dc186ad7	28	#define WORK_STRUCT_STATIC 1 /* static initializer (debugobjects) */
365970a1 DH	29	#define WORK_STRUCT_FLAG_MASK (3UL)
365970a1 DH	30	#define WORK_STRUCT_WQ_DATA_MASK (~WORK_STRUCT_FLAG_MASK)
1da177e4	31	struct list_head entry;
6bb49e59	32	work_func_t func;
4e6045f1 JB	33	#ifdef CONFIG_LOCKDEP
	34	struct lockdep_map lockdep_map;
	35	#endif
52bad64d DH	36	};
52bad64d DH	37
23b2e599	38	#define WORK_DATA_INIT() ATOMIC_LONG_INIT(0)
dc186ad7	39	#define WORK_DATA_STATIC_INIT() ATOMIC_LONG_INIT(2)
a08727ba	40
52bad64d DH	41	struct delayed_work {
52bad64d DH	42	struct work_struct work;
1da177e4 LT	43	struct timer_list timer;
	44	};
	45
bf6aede7 JD	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
1fa44eca JB	51	struct execute_work {
	52	struct work_struct work;
	53	};
	54
4e6045f1 JB	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
65f27f38	67	#define __WORK_INITIALIZER(n, f) { \
dc186ad7	68	.data = WORK_DATA_STATIC_INIT(), \
23b2e599	69	.entry = { &(n).entry, &(n).entry }, \
65f27f38	70	.func = (f), \
4e6045f1	71	__WORK_INIT_LOCKDEP_MAP(#n, &(n)) \
65f27f38 DH	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
65f27f38 DH	79	#define DECLARE_WORK(n, f) \
	80	struct work_struct n = __WORK_INITIALIZER(n, f)
	81
65f27f38 DH	82	#define DECLARE_DELAYED_WORK(n, f) \
	83	struct delayed_work n = __DELAYED_WORK_INITIALIZER(n, f)
	84
1da177e4	85	/*
65f27f38	86	* initialize a work item's function pointer
1da177e4	87	*/
65f27f38	88	#define PREPARE_WORK(_work, _func) \
1da177e4	89	do { \
52bad64d	90	(_work)->func = (_func); \
1da177e4 LT	91	} while (0)
1da177e4 LT	92
65f27f38 DH	93	#define PREPARE_DELAYED_WORK(_work, _func) \
65f27f38 DH	94	PREPARE_WORK(&(_work)->work, (_func))
52bad64d	95
dc186ad7 TG	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);
4690c4ab TH	99	static inline unsigned int work_static(struct work_struct *work)
	100	{
	101	return *work_data_bits(work) & (1 << WORK_STRUCT_STATIC);
	102	}
dc186ad7 TG	103	#else
	104	static inline void __init_work(struct work_struct *work, int onstack) { }
	105	static inline void destroy_work_on_stack(struct work_struct *work) { }
4690c4ab	106	static inline unsigned int work_static(struct work_struct *work) { return 0; }
dc186ad7 TG	107	#endif
dc186ad7 TG	108
1da177e4	109	/*
52bad64d	110	* initialize all of a work item in one go
a08727ba	111	*
b9049df5	112	* NOTE! No point in using "atomic_long_set()": using a direct
a08727ba LT	113	* assignment of the work data initializer allows the compiler
a08727ba LT	114	* to generate better code.
1da177e4	115	*/
4e6045f1	116	#ifdef CONFIG_LOCKDEP
dc186ad7	117	#define __INIT_WORK(_work, _func, _onstack) \
65f27f38	118	do { \
4e6045f1 JB	119	static struct lock_class_key __key; \
4e6045f1 JB	120	\
dc186ad7	121	__init_work((_work), _onstack); \
23b2e599	122	(_work)->data = (atomic_long_t) WORK_DATA_INIT(); \
4e6045f1	123	lockdep_init_map(&(_work)->lockdep_map, #_work, &__key, 0);\
65f27f38 DH	124	INIT_LIST_HEAD(&(_work)->entry); \
	125	PREPARE_WORK((_work), (_func)); \
	126	} while (0)
4e6045f1	127	#else
dc186ad7	128	#define __INIT_WORK(_work, _func, _onstack) \
4e6045f1	129	do { \
dc186ad7	130	__init_work((_work), _onstack); \
4e6045f1 JB	131	(_work)->data = (atomic_long_t) WORK_DATA_INIT(); \
	132	INIT_LIST_HEAD(&(_work)->entry); \
	133	PREPARE_WORK((_work), (_func)); \
	134	} while (0)
	135	#endif
65f27f38	136
dc186ad7 TG	137	#define INIT_WORK(_work, _func) \
	138	do { \
	139	__INIT_WORK((_work), (_func), 0); \
	140	} while (0)
	141
	142	#define INIT_WORK_ON_STACK(_work, _func) \
	143	do { \
	144	__INIT_WORK((_work), (_func), 1); \
	145	} while (0)
	146
65f27f38 DH	147	#define INIT_DELAYED_WORK(_work, _func) \
	148	do { \
	149	INIT_WORK(&(_work)->work, (_func)); \
	150	init_timer(&(_work)->timer); \
52bad64d DH	151	} while (0)
52bad64d DH	152
6d612b0f PZ	153	#define INIT_DELAYED_WORK_ON_STACK(_work, _func) \
6d612b0f PZ	154	do { \
dc186ad7	155	INIT_WORK_ON_STACK(&(_work)->work, (_func)); \
6d612b0f PZ	156	init_timer_on_stack(&(_work)->timer); \
	157	} while (0)
	158
dc186ad7	159	#define INIT_DELAYED_WORK_DEFERRABLE(_work, _func) \
28287033 VP	160	do { \
	161	INIT_WORK(&(_work)->work, (_func)); \
	162	init_timer_deferrable(&(_work)->timer); \
	163	} while (0)
	164
365970a1 DH	165	/**
	166	* work_pending - Find out whether a work item is currently pending
	167	* @work: The work item in question
	168	*/
	169	#define work_pending(work) \
a08727ba	170	test_bit(WORK_STRUCT_PENDING, work_data_bits(work))
365970a1 DH	171
	172	/**
	173	* delayed_work_pending - Find out whether a delayable work item is currently
	174	* pending
	175	* @work: The work item in question
	176	*/
0221872a LT	177	#define delayed_work_pending(w) \
0221872a LT	178	work_pending(&(w)->work)
365970a1	179
65f27f38	180	/**
23b2e599 ON	181	* work_clear_pending - for internal use only, mark a work item as not pending
23b2e599 ON	182	* @work: The work item in question
65f27f38	183	*/
23b2e599	184	#define work_clear_pending(work) \
a08727ba	185	clear_bit(WORK_STRUCT_PENDING, work_data_bits(work))
65f27f38	186
52bad64d	187
4e6045f1	188	extern struct workqueue_struct *
c790bce0 TH	189	__create_workqueue_key(const char *name, int singlethread, int freezeable,
c790bce0 TH	190	struct lock_class_key key, const char lock_name);
4e6045f1 JB	191
4e6045f1 JB	192	#ifdef CONFIG_LOCKDEP
c790bce0	193	#define __create_workqueue(name, singlethread, freezeable) \
4e6045f1 JB	194	({ \
4e6045f1 JB	195	static struct lock_class_key __key; \
eb13ba87 JB	196	const char *__lock_name; \
	197	\
	198	if (__builtin_constant_p(name)) \
	199	__lock_name = (name); \
	200	else \
	201	__lock_name = #name; \
4e6045f1 JB	202	\
4e6045f1 JB	203	__create_workqueue_key((name), (singlethread), \
c790bce0	204	(freezeable), &__key, \
eb13ba87	205	__lock_name); \
4e6045f1 JB	206	})
4e6045f1 JB	207	#else
c790bce0 TH	208	#define __create_workqueue(name, singlethread, freezeable) \
c790bce0 TH	209	__create_workqueue_key((name), (singlethread), (freezeable), \
0d557dc9	210	NULL, NULL)
4e6045f1 JB	211	#endif
4e6045f1 JB	212
c790bce0 TH	213	#define create_workqueue(name) __create_workqueue((name), 0, 0)
	214	#define create_freezeable_workqueue(name) __create_workqueue((name), 1, 1)
	215	#define create_singlethread_workqueue(name) __create_workqueue((name), 1, 0)
1da177e4 LT	216
	217	extern void destroy_workqueue(struct workqueue_struct *wq);
	218
b3c97528	219	extern int queue_work(struct workqueue_struct wq, struct work_struct work);
c1a220e7 ZR	220	extern int queue_work_on(int cpu, struct workqueue_struct *wq,
c1a220e7 ZR	221	struct work_struct *work);
b3c97528 HH	222	extern int queue_delayed_work(struct workqueue_struct *wq,
b3c97528 HH	223	struct delayed_work *work, unsigned long delay);
7a6bc1cd	224	extern int queue_delayed_work_on(int cpu, struct workqueue_struct *wq,
28e53bdd ON	225	struct delayed_work *work, unsigned long delay);
28e53bdd ON	226
b3c97528	227	extern void flush_workqueue(struct workqueue_struct *wq);
28e53bdd	228	extern void flush_scheduled_work(void);
43046b60	229	extern void flush_delayed_work(struct delayed_work *work);
1da177e4	230
b3c97528	231	extern int schedule_work(struct work_struct *work);
c1a220e7	232	extern int schedule_work_on(int cpu, struct work_struct *work);
b3c97528	233	extern int schedule_delayed_work(struct delayed_work *work, unsigned long delay);
28e53bdd ON	234	extern int schedule_delayed_work_on(int cpu, struct delayed_work *work,
28e53bdd ON	235	unsigned long delay);
65f27f38	236	extern int schedule_on_each_cpu(work_func_t func);
1da177e4 LT	237	extern int current_is_keventd(void);
	238	extern int keventd_up(void);
	239
	240	extern void init_workqueues(void);
65f27f38	241	int execute_in_process_context(work_func_t fn, struct execute_work *);
1da177e4	242
db700897 ON	243	extern int flush_work(struct work_struct *work);
db700897 ON	244
1f1f642e	245	extern int cancel_work_sync(struct work_struct *work);
28e53bdd	246
1da177e4 LT	247	/*
1da177e4 LT	248	* Kill off a pending schedule_delayed_work(). Note that the work callback
071b6386 ON	249	* function may still be running on return from cancel_delayed_work(), unless
071b6386 ON	250	* it returns 1 and the work doesn't re-arm itself. Run flush_workqueue() or
28e53bdd	251	* cancel_work_sync() to wait on it.
1da177e4	252	*/
52bad64d	253	static inline int cancel_delayed_work(struct delayed_work *work)
1da177e4 LT	254	{
	255	int ret;
	256
223a10a9	257	ret = del_timer_sync(&work->timer);
1da177e4	258	if (ret)
23b2e599	259	work_clear_pending(&work->work);
1da177e4 LT	260	return ret;
	261	}
	262
4e49627b ON	263	/*
	264	* Like above, but uses del_timer() instead of del_timer_sync(). This means,
	265	* if it returns 0 the timer function may be running and the queueing is in
	266	* progress.
	267	*/
	268	static inline int __cancel_delayed_work(struct delayed_work *work)
	269	{
	270	int ret;
	271
	272	ret = del_timer(&work->timer);
	273	if (ret)
	274	work_clear_pending(&work->work);
	275	return ret;
	276	}
	277
1f1f642e	278	extern int cancel_delayed_work_sync(struct delayed_work *work);
1634c48f	279
f5a421a4	280	/* Obsolete. use cancel_delayed_work_sync() */
1634c48f ON	281	static inline
	282	void cancel_rearming_delayed_workqueue(struct workqueue_struct *wq,
	283	struct delayed_work *work)
	284	{
f5a421a4 ON	285	cancel_delayed_work_sync(work);
	286	}
	287
	288	/* Obsolete. use cancel_delayed_work_sync() */
	289	static inline
	290	void cancel_rearming_delayed_work(struct delayed_work *work)
	291	{
	292	cancel_delayed_work_sync(work);
1634c48f ON	293	}
1634c48f ON	294
2d3854a3 RR	295	#ifndef CONFIG_SMP
	296	static inline long work_on_cpu(unsigned int cpu, long (fn)(void ), void *arg)
	297	{
	298	return fn(arg);
	299	}
	300	#else
	301	long work_on_cpu(unsigned int cpu, long (fn)(void ), void *arg);
	302	#endif /* CONFIG_SMP */
1da177e4	303	#endif