[mirror_ubuntu-artful-kernel.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_LINKED_BIT	= 1,	/* next work is linked to this one */
#ifdef CONFIG_DEBUG_OBJECTS_WORK
	WORK_STRUCT_STATIC_BIT	= 2,	/* static initializer (debugobjects) */
	WORK_STRUCT_COLOR_SHIFT	= 3,	/* color for workqueue flushing */
#else
	WORK_STRUCT_COLOR_SHIFT	= 2,	/* color for workqueue flushing */
#endif

	WORK_STRUCT_COLOR_BITS	= 4,

	WORK_STRUCT_PENDING	= 1 << WORK_STRUCT_PENDING_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 6 bits off of cwq pointer w/ debugobjects turned
	 * off.  This makes cwqs aligned to 64 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_SINGLE_CPU		= 1 << 1, /* only single cpu at a time */
	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_UNBOUND		= 1 << 6, /* not bound to any cpu */

	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_SINGLE_CPU | WQ_RESCUER, 1)
#define create_singlethread_workqueue(name)			\
	alloc_workqueue((name), WQ_SINGLE_CPU | 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);

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);

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 */

#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 */
affee4b2	28	WORK_STRUCT_LINKED_BIT = 1, /* next work is linked to this one */
22df02bb	29	#ifdef CONFIG_DEBUG_OBJECTS_WORK
affee4b2	30	WORK_STRUCT_STATIC_BIT = 2, /* static initializer (debugobjects) */
73f53c4a	31	WORK_STRUCT_COLOR_SHIFT = 3, /* color for workqueue flushing */
0f900049	32	#else
73f53c4a	33	WORK_STRUCT_COLOR_SHIFT = 2, /* color for workqueue flushing */
22df02bb TH	34	#endif
22df02bb TH	35
73f53c4a TH	36	WORK_STRUCT_COLOR_BITS = 4,
73f53c4a TH	37
22df02bb	38	WORK_STRUCT_PENDING = 1 << WORK_STRUCT_PENDING_BIT,
affee4b2	39	WORK_STRUCT_LINKED = 1 << WORK_STRUCT_LINKED_BIT,
22df02bb TH	40	#ifdef CONFIG_DEBUG_OBJECTS_WORK
	41	WORK_STRUCT_STATIC = 1 << WORK_STRUCT_STATIC_BIT,
	42	#else
	43	WORK_STRUCT_STATIC = 0,
	44	#endif
	45
73f53c4a TH	46	/*
	47	* The last color is no color used for works which don't
	48	* participate in workqueue flushing.
	49	*/
	50	WORK_NR_COLORS = (1 << WORK_STRUCT_COLOR_BITS) - 1,
	51	WORK_NO_COLOR = WORK_NR_COLORS,
	52
bdbc5dd7	53	/* special cpu IDs */
f3421797 TH	54	WORK_CPU_UNBOUND = NR_CPUS,
f3421797 TH	55	WORK_CPU_NONE = NR_CPUS + 1,
bdbc5dd7 TH	56	WORK_CPU_LAST = WORK_CPU_NONE,
bdbc5dd7 TH	57
73f53c4a TH	58	/*
	59	* Reserve 6 bits off of cwq pointer w/ debugobjects turned
	60	* off. This makes cwqs aligned to 64 bytes which isn't too
	61	* excessive while allowing 15 workqueue flush colors.
	62	*/
	63	WORK_STRUCT_FLAG_BITS = WORK_STRUCT_COLOR_SHIFT +
	64	WORK_STRUCT_COLOR_BITS,
	65
0f900049	66	WORK_STRUCT_FLAG_MASK = (1UL << WORK_STRUCT_FLAG_BITS) - 1,
22df02bb	67	WORK_STRUCT_WQ_DATA_MASK = ~WORK_STRUCT_FLAG_MASK,
bdbc5dd7	68	WORK_STRUCT_NO_CPU = WORK_CPU_NONE << WORK_STRUCT_FLAG_BITS,
dcd989cb TH	69
	70	/* bit mask for work_busy() return values */
	71	WORK_BUSY_PENDING = 1 << 0,
	72	WORK_BUSY_RUNNING = 1 << 1,
22df02bb TH	73	};
22df02bb TH	74
1da177e4	75	struct work_struct {
a08727ba	76	atomic_long_t data;
1da177e4	77	struct list_head entry;
6bb49e59	78	work_func_t func;
4e6045f1 JB	79	#ifdef CONFIG_LOCKDEP
	80	struct lockdep_map lockdep_map;
	81	#endif
52bad64d DH	82	};
52bad64d DH	83
7a22ad75 TH	84	#define WORK_DATA_INIT() ATOMIC_LONG_INIT(WORK_STRUCT_NO_CPU)
	85	#define WORK_DATA_STATIC_INIT() \
	86	ATOMIC_LONG_INIT(WORK_STRUCT_NO_CPU \| WORK_STRUCT_STATIC)
a08727ba	87
52bad64d DH	88	struct delayed_work {
52bad64d DH	89	struct work_struct work;
1da177e4 LT	90	struct timer_list timer;
	91	};
	92
bf6aede7 JD	93	static inline struct delayed_work to_delayed_work(struct work_struct work)
	94	{
	95	return container_of(work, struct delayed_work, work);
	96	}
	97
1fa44eca JB	98	struct execute_work {
	99	struct work_struct work;
	100	};
	101
4e6045f1 JB	102	#ifdef CONFIG_LOCKDEP
	103	/*
	104	* NB: because we have to copy the lockdep_map, setting _key
	105	* here is required, otherwise it could get initialised to the
	106	* copy of the lockdep_map!
	107	*/
	108	#define __WORK_INIT_LOCKDEP_MAP(n, k) \
	109	.lockdep_map = STATIC_LOCKDEP_MAP_INIT(n, k),
	110	#else
	111	#define __WORK_INIT_LOCKDEP_MAP(n, k)
	112	#endif
	113
65f27f38	114	#define __WORK_INITIALIZER(n, f) { \
dc186ad7	115	.data = WORK_DATA_STATIC_INIT(), \
23b2e599	116	.entry = { &(n).entry, &(n).entry }, \
65f27f38	117	.func = (f), \
4e6045f1	118	__WORK_INIT_LOCKDEP_MAP(#n, &(n)) \
65f27f38 DH	119	}
	120
	121	#define __DELAYED_WORK_INITIALIZER(n, f) { \
	122	.work = __WORK_INITIALIZER((n).work, (f)), \
	123	.timer = TIMER_INITIALIZER(NULL, 0, 0), \
	124	}
	125
65f27f38 DH	126	#define DECLARE_WORK(n, f) \
	127	struct work_struct n = __WORK_INITIALIZER(n, f)
	128
65f27f38 DH	129	#define DECLARE_DELAYED_WORK(n, f) \
	130	struct delayed_work n = __DELAYED_WORK_INITIALIZER(n, f)
	131
1da177e4	132	/*
65f27f38	133	* initialize a work item's function pointer
1da177e4	134	*/
65f27f38	135	#define PREPARE_WORK(_work, _func) \
1da177e4	136	do { \
52bad64d	137	(_work)->func = (_func); \
1da177e4 LT	138	} while (0)
1da177e4 LT	139
65f27f38 DH	140	#define PREPARE_DELAYED_WORK(_work, _func) \
65f27f38 DH	141	PREPARE_WORK(&(_work)->work, (_func))
52bad64d	142
dc186ad7 TG	143	#ifdef CONFIG_DEBUG_OBJECTS_WORK
	144	extern void __init_work(struct work_struct *work, int onstack);
	145	extern void destroy_work_on_stack(struct work_struct *work);
4690c4ab TH	146	static inline unsigned int work_static(struct work_struct *work)
4690c4ab TH	147	{
22df02bb	148	return *work_data_bits(work) & WORK_STRUCT_STATIC;
4690c4ab	149	}
dc186ad7 TG	150	#else
	151	static inline void __init_work(struct work_struct *work, int onstack) { }
	152	static inline void destroy_work_on_stack(struct work_struct *work) { }
4690c4ab	153	static inline unsigned int work_static(struct work_struct *work) { return 0; }
dc186ad7 TG	154	#endif
dc186ad7 TG	155
1da177e4	156	/*
52bad64d	157	* initialize all of a work item in one go
a08727ba	158	*
b9049df5	159	* NOTE! No point in using "atomic_long_set()": using a direct
a08727ba LT	160	* assignment of the work data initializer allows the compiler
a08727ba LT	161	* to generate better code.
1da177e4	162	*/
4e6045f1	163	#ifdef CONFIG_LOCKDEP
dc186ad7	164	#define __INIT_WORK(_work, _func, _onstack) \
65f27f38	165	do { \
4e6045f1 JB	166	static struct lock_class_key __key; \
4e6045f1 JB	167	\
dc186ad7	168	__init_work((_work), _onstack); \
23b2e599	169	(_work)->data = (atomic_long_t) WORK_DATA_INIT(); \
4e6045f1	170	lockdep_init_map(&(_work)->lockdep_map, #_work, &__key, 0);\
65f27f38 DH	171	INIT_LIST_HEAD(&(_work)->entry); \
	172	PREPARE_WORK((_work), (_func)); \
	173	} while (0)
4e6045f1	174	#else
dc186ad7	175	#define __INIT_WORK(_work, _func, _onstack) \
4e6045f1	176	do { \
dc186ad7	177	__init_work((_work), _onstack); \
4e6045f1 JB	178	(_work)->data = (atomic_long_t) WORK_DATA_INIT(); \
	179	INIT_LIST_HEAD(&(_work)->entry); \
	180	PREPARE_WORK((_work), (_func)); \
	181	} while (0)
	182	#endif
65f27f38	183
dc186ad7 TG	184	#define INIT_WORK(_work, _func) \
	185	do { \
	186	__INIT_WORK((_work), (_func), 0); \
	187	} while (0)
	188
	189	#define INIT_WORK_ON_STACK(_work, _func) \
	190	do { \
	191	__INIT_WORK((_work), (_func), 1); \
	192	} while (0)
	193
65f27f38 DH	194	#define INIT_DELAYED_WORK(_work, _func) \
	195	do { \
	196	INIT_WORK(&(_work)->work, (_func)); \
	197	init_timer(&(_work)->timer); \
52bad64d DH	198	} while (0)
52bad64d DH	199
6d612b0f PZ	200	#define INIT_DELAYED_WORK_ON_STACK(_work, _func) \
6d612b0f PZ	201	do { \
dc186ad7	202	INIT_WORK_ON_STACK(&(_work)->work, (_func)); \
6d612b0f PZ	203	init_timer_on_stack(&(_work)->timer); \
	204	} while (0)
	205
dc186ad7	206	#define INIT_DELAYED_WORK_DEFERRABLE(_work, _func) \
28287033 VP	207	do { \
	208	INIT_WORK(&(_work)->work, (_func)); \
	209	init_timer_deferrable(&(_work)->timer); \
	210	} while (0)
	211
365970a1 DH	212	/**
	213	* work_pending - Find out whether a work item is currently pending
	214	* @work: The work item in question
	215	*/
	216	#define work_pending(work) \
22df02bb	217	test_bit(WORK_STRUCT_PENDING_BIT, work_data_bits(work))
365970a1 DH	218
	219	/**
	220	* delayed_work_pending - Find out whether a delayable work item is currently
	221	* pending
	222	* @work: The work item in question
	223	*/
0221872a LT	224	#define delayed_work_pending(w) \
0221872a LT	225	work_pending(&(w)->work)
365970a1	226
65f27f38	227	/**
23b2e599 ON	228	* work_clear_pending - for internal use only, mark a work item as not pending
23b2e599 ON	229	* @work: The work item in question
65f27f38	230	*/
23b2e599	231	#define work_clear_pending(work) \
22df02bb	232	clear_bit(WORK_STRUCT_PENDING_BIT, work_data_bits(work))
65f27f38	233
97e37d7b	234	enum {
bdbc5dd7	235	WQ_NON_REENTRANT = 1 << 0, /* guarantee non-reentrance */
502ca9d8	236	WQ_SINGLE_CPU = 1 << 1, /* only single cpu at a time */
bdbc5dd7	237	WQ_FREEZEABLE = 1 << 2, /* freeze during suspend */
e22bee78	238	WQ_RESCUER = 1 << 3, /* has an rescue worker */
649027d7	239	WQ_HIGHPRI = 1 << 4, /* high priority */
fb0e7beb	240	WQ_CPU_INTENSIVE = 1 << 5, /* cpu instensive workqueue */
f3421797	241	WQ_UNBOUND = 1 << 6, /* not bound to any cpu */
b71ab8c2 TH	242
b71ab8c2 TH	243	WQ_MAX_ACTIVE = 512, /* I like 512, better ideas? */
f3421797	244	WQ_MAX_UNBOUND_PER_CPU = 4, /* 4 * #cpus for unbound wq */
b71ab8c2	245	WQ_DFL_ACTIVE = WQ_MAX_ACTIVE / 2,
97e37d7b	246	};
52bad64d	247
f3421797 TH	248	/* unbound wq's aren't per-cpu, scale max_active according to #cpus */
	249	#define WQ_UNBOUND_MAX_ACTIVE \
	250	max_t(int, WQ_MAX_ACTIVE, num_possible_cpus() * WQ_MAX_UNBOUND_PER_CPU)
	251
d320c038 TH	252	/*
	253	* System-wide workqueues which are always present.
	254	*
	255	* system_wq is the one used by schedule[_delayed]_work[_on]().
	256	* Multi-CPU multi-threaded. There are users which expect relatively
	257	* short queue flush time. Don't queue works which can run for too
	258	* long.
	259	*
	260	* system_long_wq is similar to system_wq but may host long running
	261	* works. Queue flushing might take relatively long.
	262	*
	263	* system_nrt_wq is non-reentrant and guarantees that any given work
	264	* item is never executed in parallel by multiple CPUs. Queue
	265	* flushing might take relatively long.
f3421797 TH	266	*
	267	* system_unbound_wq is unbound workqueue. Workers are not bound to
	268	* any specific CPU, not concurrency managed, and all queued works are
	269	* executed immediately as long as max_active limit is not reached and
	270	* resources are available.
d320c038 TH	271	*/
	272	extern struct workqueue_struct *system_wq;
	273	extern struct workqueue_struct *system_long_wq;
	274	extern struct workqueue_struct *system_nrt_wq;
f3421797	275	extern struct workqueue_struct *system_unbound_wq;
d320c038	276
4e6045f1	277	extern struct workqueue_struct *
d320c038 TH	278	__alloc_workqueue_key(const char *name, unsigned int flags, int max_active,
d320c038 TH	279	struct lock_class_key key, const char lock_name);
4e6045f1 JB	280
4e6045f1 JB	281	#ifdef CONFIG_LOCKDEP
d320c038	282	#define alloc_workqueue(name, flags, max_active) \
4e6045f1 JB	283	({ \
4e6045f1 JB	284	static struct lock_class_key __key; \
eb13ba87 JB	285	const char *__lock_name; \
	286	\
	287	if (__builtin_constant_p(name)) \
	288	__lock_name = (name); \
	289	else \
	290	__lock_name = #name; \
4e6045f1	291	\
d320c038 TH	292	__alloc_workqueue_key((name), (flags), (max_active), \
d320c038 TH	293	&__key, __lock_name); \
4e6045f1 JB	294	})
4e6045f1 JB	295	#else
d320c038 TH	296	#define alloc_workqueue(name, flags, max_active) \
d320c038 TH	297	__alloc_workqueue_key((name), (flags), (max_active), NULL, NULL)
4e6045f1 JB	298	#endif
4e6045f1 JB	299
97e37d7b	300	#define create_workqueue(name) \
d320c038	301	alloc_workqueue((name), WQ_RESCUER, 1)
97e37d7b	302	#define create_freezeable_workqueue(name) \
d320c038	303	alloc_workqueue((name), WQ_FREEZEABLE \| WQ_SINGLE_CPU \| WQ_RESCUER, 1)
97e37d7b	304	#define create_singlethread_workqueue(name) \
d320c038	305	alloc_workqueue((name), WQ_SINGLE_CPU \| WQ_RESCUER, 1)
1da177e4 LT	306
	307	extern void destroy_workqueue(struct workqueue_struct *wq);
	308
b3c97528	309	extern int queue_work(struct workqueue_struct wq, struct work_struct work);
c1a220e7 ZR	310	extern int queue_work_on(int cpu, struct workqueue_struct *wq,
c1a220e7 ZR	311	struct work_struct *work);
b3c97528 HH	312	extern int queue_delayed_work(struct workqueue_struct *wq,
b3c97528 HH	313	struct delayed_work *work, unsigned long delay);
7a6bc1cd	314	extern int queue_delayed_work_on(int cpu, struct workqueue_struct *wq,
28e53bdd ON	315	struct delayed_work *work, unsigned long delay);
28e53bdd ON	316
b3c97528	317	extern void flush_workqueue(struct workqueue_struct *wq);
28e53bdd	318	extern void flush_scheduled_work(void);
43046b60	319	extern void flush_delayed_work(struct delayed_work *work);
1da177e4	320
b3c97528	321	extern int schedule_work(struct work_struct *work);
c1a220e7	322	extern int schedule_work_on(int cpu, struct work_struct *work);
b3c97528	323	extern int schedule_delayed_work(struct delayed_work *work, unsigned long delay);
28e53bdd ON	324	extern int schedule_delayed_work_on(int cpu, struct delayed_work *work,
28e53bdd ON	325	unsigned long delay);
65f27f38	326	extern int schedule_on_each_cpu(work_func_t func);
1da177e4 LT	327	extern int keventd_up(void);
	328
	329	extern void init_workqueues(void);
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 */
a0a1a5fd TH	397
	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
1da177e4	404	#endif