[linux-2.6-block.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 <linux/threads.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))

enum {
	WORK_STRUCT_PENDING_BIT	= 0,	/* work item is pending execution */
	WORK_STRUCT_CWQ_BIT	= 1,	/* data points to cwq */
	WORK_STRUCT_LINKED_BIT	= 2,	/* next work is linked to this one */
#ifdef CONFIG_DEBUG_OBJECTS_WORK
	WORK_STRUCT_STATIC_BIT	= 3,	/* static initializer (debugobjects) */
	WORK_STRUCT_COLOR_SHIFT	= 4,	/* color for workqueue flushing */
#else
	WORK_STRUCT_COLOR_SHIFT	= 3,	/* color for workqueue flushing */
#endif

	WORK_STRUCT_COLOR_BITS	= 4,

	WORK_STRUCT_PENDING	= 1 << WORK_STRUCT_PENDING_BIT,
	WORK_STRUCT_CWQ		= 1 << WORK_STRUCT_CWQ_BIT,
	WORK_STRUCT_LINKED	= 1 << WORK_STRUCT_LINKED_BIT,
#ifdef CONFIG_DEBUG_OBJECTS_WORK
	WORK_STRUCT_STATIC	= 1 << WORK_STRUCT_STATIC_BIT,
#else
	WORK_STRUCT_STATIC	= 0,
#endif

	/*
	 * The last color is no color used for works which don't
	 * participate in workqueue flushing.
	 */
	WORK_NR_COLORS		= (1 << WORK_STRUCT_COLOR_BITS) - 1,
	WORK_NO_COLOR		= WORK_NR_COLORS,

	/* special cpu IDs */
	WORK_CPU_UNBOUND	= NR_CPUS,
	WORK_CPU_NONE		= NR_CPUS + 1,
	WORK_CPU_LAST		= WORK_CPU_NONE,

	/*
	 * Reserve 7 bits off of cwq pointer w/ debugobjects turned
	 * off.  This makes cwqs aligned to 128 bytes which isn't too
	 * excessive while allowing 15 workqueue flush colors.
	 */
	WORK_STRUCT_FLAG_BITS	= WORK_STRUCT_COLOR_SHIFT +
				  WORK_STRUCT_COLOR_BITS,

	WORK_STRUCT_FLAG_MASK	= (1UL << WORK_STRUCT_FLAG_BITS) - 1,
	WORK_STRUCT_WQ_DATA_MASK = ~WORK_STRUCT_FLAG_MASK,
	WORK_STRUCT_NO_CPU	= WORK_CPU_NONE << WORK_STRUCT_FLAG_BITS,

	/* bit mask for work_busy() return values */
	WORK_BUSY_PENDING	= 1 << 0,
	WORK_BUSY_RUNNING	= 1 << 1,
};

struct work_struct {
	atomic_long_t data;
	struct list_head entry;
	work_func_t func;
#ifdef CONFIG_LOCKDEP
	struct lockdep_map lockdep_map;
#endif
};

#define WORK_DATA_INIT()	ATOMIC_LONG_INIT(WORK_STRUCT_NO_CPU)
#define WORK_DATA_STATIC_INIT()	\
	ATOMIC_LONG_INIT(WORK_STRUCT_NO_CPU | WORK_STRUCT_STATIC)

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) & 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_BIT, 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_BIT, work_data_bits(work))

enum {
	WQ_NON_REENTRANT	= 1 << 0, /* guarantee non-reentrance */
	WQ_UNBOUND		= 1 << 1, /* not bound to any cpu */
	WQ_FREEZEABLE		= 1 << 2, /* freeze during suspend */
	WQ_RESCUER		= 1 << 3, /* has an rescue worker */
	WQ_HIGHPRI		= 1 << 4, /* high priority */
	WQ_CPU_INTENSIVE	= 1 << 5, /* cpu instensive workqueue */

	WQ_MAX_ACTIVE		= 512,	  /* I like 512, better ideas? */
	WQ_MAX_UNBOUND_PER_CPU	= 4,	  /* 4 * #cpus for unbound wq */
	WQ_DFL_ACTIVE		= WQ_MAX_ACTIVE / 2,
};

/* unbound wq's aren't per-cpu, scale max_active according to #cpus */
#define WQ_UNBOUND_MAX_ACTIVE	\
	max_t(int, WQ_MAX_ACTIVE, num_possible_cpus() * WQ_MAX_UNBOUND_PER_CPU)

/*
 * System-wide workqueues which are always present.
 *
 * system_wq is the one used by schedule[_delayed]_work[_on]().
 * Multi-CPU multi-threaded.  There are users which expect relatively
 * short queue flush time.  Don't queue works which can run for too
 * long.
 *
 * system_long_wq is similar to system_wq but may host long running
 * works.  Queue flushing might take relatively long.
 *
 * system_nrt_wq is non-reentrant and guarantees that any given work
 * item is never executed in parallel by multiple CPUs.  Queue
 * flushing might take relatively long.
 *
 * system_unbound_wq is unbound workqueue.  Workers are not bound to
 * any specific CPU, not concurrency managed, and all queued works are
 * executed immediately as long as max_active limit is not reached and
 * resources are available.
 */
extern struct workqueue_struct *system_wq;
extern struct workqueue_struct *system_long_wq;
extern struct workqueue_struct *system_nrt_wq;
extern struct workqueue_struct *system_unbound_wq;

extern struct workqueue_struct *
__alloc_workqueue_key(const char *name, unsigned int flags, int max_active,
		      struct lock_class_key *key, const char *lock_name);

#ifdef CONFIG_LOCKDEP
#define alloc_workqueue(name, flags, max_active)		\
({								\
	static struct lock_class_key __key;			\
	const char *__lock_name;				\
								\
	if (__builtin_constant_p(name))				\
		__lock_name = (name);				\
	else							\
		__lock_name = #name;				\
								\
	__alloc_workqueue_key((name), (flags), (max_active),	\
			      &__key, __lock_name);		\
})
#else
#define alloc_workqueue(name, flags, max_active)		\
	__alloc_workqueue_key((name), (flags), (max_active), NULL, NULL)
#endif

#define create_workqueue(name)					\
	alloc_workqueue((name), WQ_RESCUER, 1)
#define create_freezeable_workqueue(name)			\
	alloc_workqueue((name), WQ_FREEZEABLE | WQ_UNBOUND | WQ_RESCUER, 1)
#define create_singlethread_workqueue(name)			\
	alloc_workqueue((name), WQ_UNBOUND | WQ_RESCUER, 1)

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 keventd_up(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);

extern void workqueue_set_max_active(struct workqueue_struct *wq,
				     int max_active);
extern bool workqueue_congested(unsigned int cpu, struct workqueue_struct *wq);
extern unsigned int work_cpu(struct work_struct *work);
extern unsigned int work_busy(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 */

#ifdef CONFIG_FREEZER
extern void freeze_workqueues_begin(void);
extern bool freeze_workqueues_busy(void);
extern void thaw_workqueues(void);
#endif /* CONFIG_FREEZER */

#ifdef CONFIG_LOCKDEP
int in_workqueue_context(struct workqueue_struct *wq);
#endif

#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>
7a22ad75	12	#include <linux/threads.h>
a08727ba	13	#include <asm/atomic.h>
1da177e4 LT	14
	15	struct workqueue_struct;
	16
65f27f38 DH	17	struct work_struct;
65f27f38 DH	18	typedef void (work_func_t)(struct work_struct work);
6bb49e59	19
a08727ba LT	20	/*
	21	* The first word is the work queue pointer and the flags rolled into
	22	* one
	23	*/
	24	#define work_data_bits(work) ((unsigned long *)(&(work)->data))
	25
22df02bb TH	26	enum {
22df02bb TH	27	WORK_STRUCT_PENDING_BIT = 0, /* work item is pending execution */
e120153d TH	28	WORK_STRUCT_CWQ_BIT = 1, /* data points to cwq */
e120153d TH	29	WORK_STRUCT_LINKED_BIT = 2, /* next work is linked to this one */
22df02bb	30	#ifdef CONFIG_DEBUG_OBJECTS_WORK
e120153d TH	31	WORK_STRUCT_STATIC_BIT = 3, /* static initializer (debugobjects) */
e120153d TH	32	WORK_STRUCT_COLOR_SHIFT = 4, /* color for workqueue flushing */
0f900049	33	#else
e120153d	34	WORK_STRUCT_COLOR_SHIFT = 3, /* color for workqueue flushing */
22df02bb TH	35	#endif
22df02bb TH	36
73f53c4a TH	37	WORK_STRUCT_COLOR_BITS = 4,
73f53c4a TH	38
22df02bb	39	WORK_STRUCT_PENDING = 1 << WORK_STRUCT_PENDING_BIT,
e120153d	40	WORK_STRUCT_CWQ = 1 << WORK_STRUCT_CWQ_BIT,
affee4b2	41	WORK_STRUCT_LINKED = 1 << WORK_STRUCT_LINKED_BIT,
22df02bb TH	42	#ifdef CONFIG_DEBUG_OBJECTS_WORK
	43	WORK_STRUCT_STATIC = 1 << WORK_STRUCT_STATIC_BIT,
	44	#else
	45	WORK_STRUCT_STATIC = 0,
	46	#endif
	47
73f53c4a TH	48	/*
	49	* The last color is no color used for works which don't
	50	* participate in workqueue flushing.
	51	*/
	52	WORK_NR_COLORS = (1 << WORK_STRUCT_COLOR_BITS) - 1,
	53	WORK_NO_COLOR = WORK_NR_COLORS,
	54
bdbc5dd7	55	/* special cpu IDs */
f3421797 TH	56	WORK_CPU_UNBOUND = NR_CPUS,
f3421797 TH	57	WORK_CPU_NONE = NR_CPUS + 1,
bdbc5dd7 TH	58	WORK_CPU_LAST = WORK_CPU_NONE,
bdbc5dd7 TH	59
73f53c4a	60	/*
e120153d TH	61	* Reserve 7 bits off of cwq pointer w/ debugobjects turned
e120153d TH	62	* off. This makes cwqs aligned to 128 bytes which isn't too
73f53c4a TH	63	* excessive while allowing 15 workqueue flush colors.
	64	*/
	65	WORK_STRUCT_FLAG_BITS = WORK_STRUCT_COLOR_SHIFT +
	66	WORK_STRUCT_COLOR_BITS,
	67
0f900049	68	WORK_STRUCT_FLAG_MASK = (1UL << WORK_STRUCT_FLAG_BITS) - 1,
22df02bb	69	WORK_STRUCT_WQ_DATA_MASK = ~WORK_STRUCT_FLAG_MASK,
bdbc5dd7	70	WORK_STRUCT_NO_CPU = WORK_CPU_NONE << WORK_STRUCT_FLAG_BITS,
dcd989cb TH	71
	72	/* bit mask for work_busy() return values */
	73	WORK_BUSY_PENDING = 1 << 0,
	74	WORK_BUSY_RUNNING = 1 << 1,
22df02bb TH	75	};
22df02bb TH	76
1da177e4	77	struct work_struct {
a08727ba	78	atomic_long_t data;
1da177e4	79	struct list_head entry;
6bb49e59	80	work_func_t func;
4e6045f1 JB	81	#ifdef CONFIG_LOCKDEP
	82	struct lockdep_map lockdep_map;
	83	#endif
52bad64d DH	84	};
52bad64d DH	85
7a22ad75 TH	86	#define WORK_DATA_INIT() ATOMIC_LONG_INIT(WORK_STRUCT_NO_CPU)
	87	#define WORK_DATA_STATIC_INIT() \
	88	ATOMIC_LONG_INIT(WORK_STRUCT_NO_CPU \| WORK_STRUCT_STATIC)
a08727ba	89
52bad64d DH	90	struct delayed_work {
52bad64d DH	91	struct work_struct work;
1da177e4 LT	92	struct timer_list timer;
	93	};
	94
bf6aede7 JD	95	static inline struct delayed_work to_delayed_work(struct work_struct work)
	96	{
	97	return container_of(work, struct delayed_work, work);
	98	}
	99
1fa44eca JB	100	struct execute_work {
	101	struct work_struct work;
	102	};
	103
4e6045f1 JB	104	#ifdef CONFIG_LOCKDEP
	105	/*
	106	* NB: because we have to copy the lockdep_map, setting _key
	107	* here is required, otherwise it could get initialised to the
	108	* copy of the lockdep_map!
	109	*/
	110	#define __WORK_INIT_LOCKDEP_MAP(n, k) \
	111	.lockdep_map = STATIC_LOCKDEP_MAP_INIT(n, k),
	112	#else
	113	#define __WORK_INIT_LOCKDEP_MAP(n, k)
	114	#endif
	115
65f27f38	116	#define __WORK_INITIALIZER(n, f) { \
dc186ad7	117	.data = WORK_DATA_STATIC_INIT(), \
23b2e599	118	.entry = { &(n).entry, &(n).entry }, \
65f27f38	119	.func = (f), \
4e6045f1	120	__WORK_INIT_LOCKDEP_MAP(#n, &(n)) \
65f27f38 DH	121	}
	122
	123	#define __DELAYED_WORK_INITIALIZER(n, f) { \
	124	.work = __WORK_INITIALIZER((n).work, (f)), \
	125	.timer = TIMER_INITIALIZER(NULL, 0, 0), \
	126	}
	127
65f27f38 DH	128	#define DECLARE_WORK(n, f) \
	129	struct work_struct n = __WORK_INITIALIZER(n, f)
	130
65f27f38 DH	131	#define DECLARE_DELAYED_WORK(n, f) \
	132	struct delayed_work n = __DELAYED_WORK_INITIALIZER(n, f)
	133
1da177e4	134	/*
65f27f38	135	* initialize a work item's function pointer
1da177e4	136	*/
65f27f38	137	#define PREPARE_WORK(_work, _func) \
1da177e4	138	do { \
52bad64d	139	(_work)->func = (_func); \
1da177e4 LT	140	} while (0)
1da177e4 LT	141
65f27f38 DH	142	#define PREPARE_DELAYED_WORK(_work, _func) \
65f27f38 DH	143	PREPARE_WORK(&(_work)->work, (_func))
52bad64d	144
dc186ad7 TG	145	#ifdef CONFIG_DEBUG_OBJECTS_WORK
	146	extern void __init_work(struct work_struct *work, int onstack);
	147	extern void destroy_work_on_stack(struct work_struct *work);
4690c4ab TH	148	static inline unsigned int work_static(struct work_struct *work)
4690c4ab TH	149	{
22df02bb	150	return *work_data_bits(work) & WORK_STRUCT_STATIC;
4690c4ab	151	}
dc186ad7 TG	152	#else
	153	static inline void __init_work(struct work_struct *work, int onstack) { }
	154	static inline void destroy_work_on_stack(struct work_struct *work) { }
4690c4ab	155	static inline unsigned int work_static(struct work_struct *work) { return 0; }
dc186ad7 TG	156	#endif
dc186ad7 TG	157
1da177e4	158	/*
52bad64d	159	* initialize all of a work item in one go
a08727ba	160	*
b9049df5	161	* NOTE! No point in using "atomic_long_set()": using a direct
a08727ba LT	162	* assignment of the work data initializer allows the compiler
a08727ba LT	163	* to generate better code.
1da177e4	164	*/
4e6045f1	165	#ifdef CONFIG_LOCKDEP
dc186ad7	166	#define __INIT_WORK(_work, _func, _onstack) \
65f27f38	167	do { \
4e6045f1 JB	168	static struct lock_class_key __key; \
4e6045f1 JB	169	\
dc186ad7	170	__init_work((_work), _onstack); \
23b2e599	171	(_work)->data = (atomic_long_t) WORK_DATA_INIT(); \
4e6045f1	172	lockdep_init_map(&(_work)->lockdep_map, #_work, &__key, 0);\
65f27f38 DH	173	INIT_LIST_HEAD(&(_work)->entry); \
	174	PREPARE_WORK((_work), (_func)); \
	175	} while (0)
4e6045f1	176	#else
dc186ad7	177	#define __INIT_WORK(_work, _func, _onstack) \
4e6045f1	178	do { \
dc186ad7	179	__init_work((_work), _onstack); \
4e6045f1 JB	180	(_work)->data = (atomic_long_t) WORK_DATA_INIT(); \
	181	INIT_LIST_HEAD(&(_work)->entry); \
	182	PREPARE_WORK((_work), (_func)); \
	183	} while (0)
	184	#endif
65f27f38	185
dc186ad7 TG	186	#define INIT_WORK(_work, _func) \
	187	do { \
	188	__INIT_WORK((_work), (_func), 0); \
	189	} while (0)
	190
	191	#define INIT_WORK_ON_STACK(_work, _func) \
	192	do { \
	193	__INIT_WORK((_work), (_func), 1); \
	194	} while (0)
	195
65f27f38 DH	196	#define INIT_DELAYED_WORK(_work, _func) \
	197	do { \
	198	INIT_WORK(&(_work)->work, (_func)); \
	199	init_timer(&(_work)->timer); \
52bad64d DH	200	} while (0)
52bad64d DH	201
6d612b0f PZ	202	#define INIT_DELAYED_WORK_ON_STACK(_work, _func) \
6d612b0f PZ	203	do { \
dc186ad7	204	INIT_WORK_ON_STACK(&(_work)->work, (_func)); \
6d612b0f PZ	205	init_timer_on_stack(&(_work)->timer); \
	206	} while (0)
	207
dc186ad7	208	#define INIT_DELAYED_WORK_DEFERRABLE(_work, _func) \
28287033 VP	209	do { \
	210	INIT_WORK(&(_work)->work, (_func)); \
	211	init_timer_deferrable(&(_work)->timer); \
	212	} while (0)
	213
365970a1 DH	214	/**
	215	* work_pending - Find out whether a work item is currently pending
	216	* @work: The work item in question
	217	*/
	218	#define work_pending(work) \
22df02bb	219	test_bit(WORK_STRUCT_PENDING_BIT, work_data_bits(work))
365970a1 DH	220
	221	/**
	222	* delayed_work_pending - Find out whether a delayable work item is currently
	223	* pending
	224	* @work: The work item in question
	225	*/
0221872a LT	226	#define delayed_work_pending(w) \
0221872a LT	227	work_pending(&(w)->work)
365970a1	228
65f27f38	229	/**
23b2e599 ON	230	* work_clear_pending - for internal use only, mark a work item as not pending
23b2e599 ON	231	* @work: The work item in question
65f27f38	232	*/
23b2e599	233	#define work_clear_pending(work) \
22df02bb	234	clear_bit(WORK_STRUCT_PENDING_BIT, work_data_bits(work))
65f27f38	235
97e37d7b	236	enum {
bdbc5dd7	237	WQ_NON_REENTRANT = 1 << 0, /* guarantee non-reentrance */
c7fc77f7	238	WQ_UNBOUND = 1 << 1, /* not bound to any cpu */
bdbc5dd7	239	WQ_FREEZEABLE = 1 << 2, /* freeze during suspend */
e22bee78	240	WQ_RESCUER = 1 << 3, /* has an rescue worker */
649027d7	241	WQ_HIGHPRI = 1 << 4, /* high priority */
fb0e7beb	242	WQ_CPU_INTENSIVE = 1 << 5, /* cpu instensive workqueue */
b71ab8c2 TH	243
b71ab8c2 TH	244	WQ_MAX_ACTIVE = 512, /* I like 512, better ideas? */
f3421797	245	WQ_MAX_UNBOUND_PER_CPU = 4, /* 4 * #cpus for unbound wq */
b71ab8c2	246	WQ_DFL_ACTIVE = WQ_MAX_ACTIVE / 2,
97e37d7b	247	};
52bad64d	248
f3421797 TH	249	/* unbound wq's aren't per-cpu, scale max_active according to #cpus */
	250	#define WQ_UNBOUND_MAX_ACTIVE \
	251	max_t(int, WQ_MAX_ACTIVE, num_possible_cpus() * WQ_MAX_UNBOUND_PER_CPU)
65f27f38	252
d320c038 TH	253	/*
	254	* System-wide workqueues which are always present.
	255	*
	256	* system_wq is the one used by schedule[_delayed]_work[_on]().
	257	* Multi-CPU multi-threaded. There are users which expect relatively
	258	* short queue flush time. Don't queue works which can run for too
	259	* long.
	260	*
	261	* system_long_wq is similar to system_wq but may host long running
	262	* works. Queue flushing might take relatively long.
	263	*
	264	* system_nrt_wq is non-reentrant and guarantees that any given work
	265	* item is never executed in parallel by multiple CPUs. Queue
	266	* flushing might take relatively long.
f3421797 TH	267	*
	268	* system_unbound_wq is unbound workqueue. Workers are not bound to
	269	* any specific CPU, not concurrency managed, and all queued works are
	270	* executed immediately as long as max_active limit is not reached and
	271	* resources are available.
d320c038 TH	272	*/
	273	extern struct workqueue_struct *system_wq;
	274	extern struct workqueue_struct *system_long_wq;
	275	extern struct workqueue_struct *system_nrt_wq;
f3421797	276	extern struct workqueue_struct *system_unbound_wq;
52bad64d	277
4e6045f1	278	extern struct workqueue_struct *
d320c038 TH	279	__alloc_workqueue_key(const char *name, unsigned int flags, int max_active,
d320c038 TH	280	struct lock_class_key key, const char lock_name);
4e6045f1 JB	281
4e6045f1 JB	282	#ifdef CONFIG_LOCKDEP
d320c038	283	#define alloc_workqueue(name, flags, max_active) \
4e6045f1 JB	284	({ \
4e6045f1 JB	285	static struct lock_class_key __key; \
eb13ba87 JB	286	const char *__lock_name; \
	287	\
	288	if (__builtin_constant_p(name)) \
	289	__lock_name = (name); \
	290	else \
	291	__lock_name = #name; \
4e6045f1	292	\
d320c038 TH	293	__alloc_workqueue_key((name), (flags), (max_active), \
d320c038 TH	294	&__key, __lock_name); \
4e6045f1 JB	295	})
4e6045f1 JB	296	#else
d320c038 TH	297	#define alloc_workqueue(name, flags, max_active) \
d320c038 TH	298	__alloc_workqueue_key((name), (flags), (max_active), NULL, NULL)
4e6045f1 JB	299	#endif
4e6045f1 JB	300
97e37d7b	301	#define create_workqueue(name) \
d320c038	302	alloc_workqueue((name), WQ_RESCUER, 1)
97e37d7b	303	#define create_freezeable_workqueue(name) \
c7fc77f7	304	alloc_workqueue((name), WQ_FREEZEABLE \| WQ_UNBOUND \| WQ_RESCUER, 1)
97e37d7b	305	#define create_singlethread_workqueue(name) \
c7fc77f7	306	alloc_workqueue((name), WQ_UNBOUND \| WQ_RESCUER, 1)
1da177e4 LT	307
	308	extern void destroy_workqueue(struct workqueue_struct *wq);
	309
b3c97528	310	extern int queue_work(struct workqueue_struct wq, struct work_struct work);
c1a220e7 ZR	311	extern int queue_work_on(int cpu, struct workqueue_struct *wq,
c1a220e7 ZR	312	struct work_struct *work);
b3c97528 HH	313	extern int queue_delayed_work(struct workqueue_struct *wq,
b3c97528 HH	314	struct delayed_work *work, unsigned long delay);
7a6bc1cd	315	extern int queue_delayed_work_on(int cpu, struct workqueue_struct *wq,
28e53bdd ON	316	struct delayed_work *work, unsigned long delay);
28e53bdd ON	317
b3c97528	318	extern void flush_workqueue(struct workqueue_struct *wq);
28e53bdd	319	extern void flush_scheduled_work(void);
43046b60	320	extern void flush_delayed_work(struct delayed_work *work);
1da177e4	321
b3c97528	322	extern int schedule_work(struct work_struct *work);
c1a220e7	323	extern int schedule_work_on(int cpu, struct work_struct *work);
b3c97528	324	extern int schedule_delayed_work(struct delayed_work *work, unsigned long delay);
28e53bdd ON	325	extern int schedule_delayed_work_on(int cpu, struct delayed_work *work,
28e53bdd ON	326	unsigned long delay);
65f27f38	327	extern int schedule_on_each_cpu(work_func_t func);
1da177e4 LT	328	extern int keventd_up(void);
1da177e4 LT	329
65f27f38	330	int execute_in_process_context(work_func_t fn, struct execute_work *);
1da177e4	331
db700897	332	extern int flush_work(struct work_struct *work);
1f1f642e	333	extern int cancel_work_sync(struct work_struct *work);
28e53bdd	334
dcd989cb TH	335	extern void workqueue_set_max_active(struct workqueue_struct *wq,
	336	int max_active);
	337	extern bool workqueue_congested(unsigned int cpu, struct workqueue_struct *wq);
	338	extern unsigned int work_cpu(struct work_struct *work);
	339	extern unsigned int work_busy(struct work_struct *work);
	340
1da177e4 LT	341	/*
1da177e4 LT	342	* Kill off a pending schedule_delayed_work(). Note that the work callback
071b6386 ON	343	* function may still be running on return from cancel_delayed_work(), unless
071b6386 ON	344	* it returns 1 and the work doesn't re-arm itself. Run flush_workqueue() or
28e53bdd	345	* cancel_work_sync() to wait on it.
1da177e4	346	*/
52bad64d	347	static inline int cancel_delayed_work(struct delayed_work *work)
1da177e4 LT	348	{
	349	int ret;
	350
223a10a9	351	ret = del_timer_sync(&work->timer);
1da177e4	352	if (ret)
23b2e599	353	work_clear_pending(&work->work);
1da177e4 LT	354	return ret;
	355	}
	356
4e49627b ON	357	/*
	358	* Like above, but uses del_timer() instead of del_timer_sync(). This means,
	359	* if it returns 0 the timer function may be running and the queueing is in
	360	* progress.
	361	*/
	362	static inline int __cancel_delayed_work(struct delayed_work *work)
	363	{
	364	int ret;
	365
	366	ret = del_timer(&work->timer);
	367	if (ret)
	368	work_clear_pending(&work->work);
	369	return ret;
	370	}
	371
1f1f642e	372	extern int cancel_delayed_work_sync(struct delayed_work *work);
1634c48f	373
f5a421a4	374	/* Obsolete. use cancel_delayed_work_sync() */
1634c48f ON	375	static inline
	376	void cancel_rearming_delayed_workqueue(struct workqueue_struct *wq,
	377	struct delayed_work *work)
	378	{
f5a421a4 ON	379	cancel_delayed_work_sync(work);
	380	}
	381
	382	/* Obsolete. use cancel_delayed_work_sync() */
	383	static inline
	384	void cancel_rearming_delayed_work(struct delayed_work *work)
	385	{
	386	cancel_delayed_work_sync(work);
1634c48f ON	387	}
1634c48f ON	388
2d3854a3 RR	389	#ifndef CONFIG_SMP
	390	static inline long work_on_cpu(unsigned int cpu, long (fn)(void ), void *arg)
	391	{
	392	return fn(arg);
	393	}
	394	#else
	395	long work_on_cpu(unsigned int cpu, long (fn)(void ), void *arg);
	396	#endif /* CONFIG_SMP */
a25909a4	397
a0a1a5fd TH	398	#ifdef CONFIG_FREEZER
	399	extern void freeze_workqueues_begin(void);
	400	extern bool freeze_workqueues_busy(void);
	401	extern void thaw_workqueues(void);
	402	#endif /* CONFIG_FREEZER */
	403
a25909a4 PM	404	#ifdef CONFIG_LOCKDEP
	405	int in_workqueue_context(struct workqueue_struct *wq);
	406	#endif
3b7433b8	407
1da177e4	408	#endif