[deliverable/linux.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 <linux/atomic.h>

struct workqueue_struct;

struct work_struct;
typedef void (*work_func_t)(struct work_struct *work);
void delayed_work_timer_fn(unsigned long __data);

/*
 * 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_DELAYED_BIT	= 1,	/* work item is delayed */
	WORK_STRUCT_PWQ_BIT	= 2,	/* data points to pwq */
	WORK_STRUCT_LINKED_BIT	= 3,	/* next work is linked to this one */
#ifdef CONFIG_DEBUG_OBJECTS_WORK
	WORK_STRUCT_STATIC_BIT	= 4,	/* static initializer (debugobjects) */
	WORK_STRUCT_COLOR_SHIFT	= 5,	/* color for workqueue flushing */
#else
	WORK_STRUCT_COLOR_SHIFT	= 4,	/* color for workqueue flushing */
#endif

	WORK_STRUCT_COLOR_BITS	= 4,

	WORK_STRUCT_PENDING	= 1 << WORK_STRUCT_PENDING_BIT,
	WORK_STRUCT_DELAYED	= 1 << WORK_STRUCT_DELAYED_BIT,
	WORK_STRUCT_PWQ		= 1 << WORK_STRUCT_PWQ_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_END		= NR_CPUS + 1,

	/*
	 * Reserve 7 bits off of pwq pointer w/ debugobjects turned off.
	 * This makes pwqs aligned to 256 bytes and allows 15 workqueue
	 * flush colors.
	 */
	WORK_STRUCT_FLAG_BITS	= WORK_STRUCT_COLOR_SHIFT +
				  WORK_STRUCT_COLOR_BITS,

	/* data contains off-queue information when !WORK_STRUCT_PWQ */
	WORK_OFFQ_FLAG_BASE	= WORK_STRUCT_COLOR_SHIFT,

	WORK_OFFQ_CANCELING	= (1 << WORK_OFFQ_FLAG_BASE),

	/*
	 * When a work item is off queue, its high bits point to the last
	 * pool it was on.  Cap at 31 bits and use the highest number to
	 * indicate that no pool is associated.
	 */
	WORK_OFFQ_FLAG_BITS	= 1,
	WORK_OFFQ_POOL_SHIFT	= WORK_OFFQ_FLAG_BASE + WORK_OFFQ_FLAG_BITS,
	WORK_OFFQ_LEFT		= BITS_PER_LONG - WORK_OFFQ_POOL_SHIFT,
	WORK_OFFQ_POOL_BITS	= WORK_OFFQ_LEFT <= 31 ? WORK_OFFQ_LEFT : 31,
	WORK_OFFQ_POOL_NONE	= (1LU << WORK_OFFQ_POOL_BITS) - 1,

	/* convenience constants */
	WORK_STRUCT_FLAG_MASK	= (1UL << WORK_STRUCT_FLAG_BITS) - 1,
	WORK_STRUCT_WQ_DATA_MASK = ~WORK_STRUCT_FLAG_MASK,
	WORK_STRUCT_NO_POOL	= (unsigned long)WORK_OFFQ_POOL_NONE << WORK_OFFQ_POOL_SHIFT,

	/* 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_POOL)
#define WORK_DATA_STATIC_INIT()	\
	ATOMIC_LONG_INIT(WORK_STRUCT_NO_POOL | WORK_STRUCT_STATIC)

struct delayed_work {
	struct work_struct work;
	struct timer_list timer;

	/* target workqueue and CPU ->timer uses to queue ->work */
	struct workqueue_struct *wq;
	int cpu;
};

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, tflags) {			\
	.work = __WORK_INITIALIZER((n).work, (f)),			\
	.timer = __TIMER_INITIALIZER(delayed_work_timer_fn,		\
				     0, (unsigned long)&(n),		\
				     (tflags) | TIMER_IRQSAFE),		\
	}

#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, 0)

#define DECLARE_DEFERRABLE_WORK(n, f)					\
	struct delayed_work n = __DELAYED_WORK_INITIALIZER(n, f, TIMER_DEFERRABLE)

/*
 * 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_ONSTACK(_work, _func)					\
	do {								\
		__INIT_WORK((_work), (_func), 1);			\
	} while (0)

#define __INIT_DELAYED_WORK(_work, _func, _tflags)			\
	do {								\
		INIT_WORK(&(_work)->work, (_func));			\
		__setup_timer(&(_work)->timer, delayed_work_timer_fn,	\
			      (unsigned long)(_work),			\
			      (_tflags) | TIMER_IRQSAFE);		\
	} while (0)

#define __INIT_DELAYED_WORK_ONSTACK(_work, _func, _tflags)		\
	do {								\
		INIT_WORK_ONSTACK(&(_work)->work, (_func));		\
		__setup_timer_on_stack(&(_work)->timer,			\
				       delayed_work_timer_fn,		\
				       (unsigned long)(_work),		\
				       (_tflags) | TIMER_IRQSAFE);	\
	} while (0)

#define INIT_DELAYED_WORK(_work, _func)					\
	__INIT_DELAYED_WORK(_work, _func, 0)

#define INIT_DELAYED_WORK_ONSTACK(_work, _func)				\
	__INIT_DELAYED_WORK_ONSTACK(_work, _func, 0)

#define INIT_DEFERRABLE_WORK(_work, _func)				\
	__INIT_DELAYED_WORK(_work, _func, TIMER_DEFERRABLE)

#define INIT_DEFERRABLE_WORK_ONSTACK(_work, _func)			\
	__INIT_DELAYED_WORK_ONSTACK(_work, _func, TIMER_DEFERRABLE)

/**
 * 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))

/*
 * Workqueue flags and constants.  For details, please refer to
 * Documentation/workqueue.txt.
 */
enum {
	WQ_NON_REENTRANT	= 1 << 0, /* guarantee non-reentrance */
	WQ_UNBOUND		= 1 << 1, /* not bound to any cpu */
	WQ_FREEZABLE		= 1 << 2, /* freeze during suspend */
	WQ_MEM_RECLAIM		= 1 << 3, /* may be used for memory reclaim */
	WQ_HIGHPRI		= 1 << 4, /* high priority */
	WQ_CPU_INTENSIVE	= 1 << 5, /* cpu instensive workqueue */

	WQ_DRAINING		= 1 << 6, /* internal: workqueue is draining */
	WQ_RESCUER		= 1 << 7, /* internal: workqueue has rescuer */

	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_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.
 *
 * system_freezable_wq is equivalent to system_wq except that it's
 * freezable.
 */
extern struct workqueue_struct *system_wq;
extern struct workqueue_struct *system_long_wq;
extern struct workqueue_struct *system_unbound_wq;
extern struct workqueue_struct *system_freezable_wq;

static inline struct workqueue_struct * __deprecated __system_nrt_wq(void)
{
	return system_wq;
}

static inline struct workqueue_struct * __deprecated __system_nrt_freezable_wq(void)
{
	return system_freezable_wq;
}

/* equivlalent to system_wq and system_freezable_wq, deprecated */
#define system_nrt_wq			__system_nrt_wq()
#define system_nrt_freezable_wq		__system_nrt_freezable_wq()

extern struct workqueue_struct *
__alloc_workqueue_key(const char *fmt, unsigned int flags, int max_active,
	struct lock_class_key *key, const char *lock_name, ...) __printf(1, 6);

/**
 * alloc_workqueue - allocate a workqueue
 * @fmt: printf format for the name of the workqueue
 * @flags: WQ_* flags
 * @max_active: max in-flight work items, 0 for default
 * @args: args for @fmt
 *
 * Allocate a workqueue with the specified parameters.  For detailed
 * information on WQ_* flags, please refer to Documentation/workqueue.txt.
 *
 * The __lock_name macro dance is to guarantee that single lock_class_key
 * doesn't end up with different namesm, which isn't allowed by lockdep.
 *
 * RETURNS:
 * Pointer to the allocated workqueue on success, %NULL on failure.
 */
#ifdef CONFIG_LOCKDEP
#define alloc_workqueue(fmt, flags, max_active, args...)		\
({									\
	static struct lock_class_key __key;				\
	const char *__lock_name;					\
									\
	if (__builtin_constant_p(fmt))					\
		__lock_name = (fmt);					\
	else								\
		__lock_name = #fmt;					\
									\
	__alloc_workqueue_key((fmt), (flags), (max_active),		\
			      &__key, __lock_name, ##args);		\
})
#else
#define alloc_workqueue(fmt, flags, max_active, args...)		\
	__alloc_workqueue_key((fmt), (flags), (max_active),		\
			      NULL, NULL, ##args)
#endif

/**
 * alloc_ordered_workqueue - allocate an ordered workqueue
 * @fmt: printf format for the name of the workqueue
 * @flags: WQ_* flags (only WQ_FREEZABLE and WQ_MEM_RECLAIM are meaningful)
 * @args: args for @fmt
 *
 * Allocate an ordered workqueue.  An ordered workqueue executes at
 * most one work item at any given time in the queued order.  They are
 * implemented as unbound workqueues with @max_active of one.
 *
 * RETURNS:
 * Pointer to the allocated workqueue on success, %NULL on failure.
 */
#define alloc_ordered_workqueue(fmt, flags, args...)			\
	alloc_workqueue(fmt, WQ_UNBOUND | (flags), 1, ##args)

#define create_workqueue(name)						\
	alloc_workqueue((name), WQ_MEM_RECLAIM, 1)
#define create_freezable_workqueue(name)				\
	alloc_workqueue((name), WQ_FREEZABLE | WQ_UNBOUND | WQ_MEM_RECLAIM, 1)
#define create_singlethread_workqueue(name)				\
	alloc_workqueue((name), WQ_UNBOUND | WQ_MEM_RECLAIM, 1)

extern void destroy_workqueue(struct workqueue_struct *wq);

extern bool queue_work_on(int cpu, struct workqueue_struct *wq,
			struct work_struct *work);
extern bool queue_work(struct workqueue_struct *wq, struct work_struct *work);
extern bool queue_delayed_work_on(int cpu, struct workqueue_struct *wq,
			struct delayed_work *work, unsigned long delay);
extern bool queue_delayed_work(struct workqueue_struct *wq,
			struct delayed_work *work, unsigned long delay);
extern bool mod_delayed_work_on(int cpu, struct workqueue_struct *wq,
			struct delayed_work *dwork, unsigned long delay);
extern bool mod_delayed_work(struct workqueue_struct *wq,
			struct delayed_work *dwork, unsigned long delay);

extern void flush_workqueue(struct workqueue_struct *wq);
extern void drain_workqueue(struct workqueue_struct *wq);
extern void flush_scheduled_work(void);

extern bool schedule_work_on(int cpu, struct work_struct *work);
extern bool schedule_work(struct work_struct *work);
extern bool schedule_delayed_work_on(int cpu, struct delayed_work *work,
				     unsigned long delay);
extern bool schedule_delayed_work(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 bool flush_work(struct work_struct *work);
extern bool cancel_work_sync(struct work_struct *work);

extern bool flush_delayed_work(struct delayed_work *dwork);
extern bool cancel_delayed_work(struct delayed_work *dwork);
extern bool cancel_delayed_work_sync(struct delayed_work *dwork);

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_busy(struct work_struct *work);

/*
 * 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 bool __deprecated __cancel_delayed_work(struct delayed_work *work)
{
	bool ret;

	ret = del_timer(&work->timer);
	if (ret)
		work_clear_pending(&work->work);
	return ret;
}

/* used to be different but now identical to flush_work(), deprecated */
static inline bool __deprecated flush_work_sync(struct work_struct *work)
{
	return flush_work(work);
}

/* used to be different but now identical to flush_delayed_work(), deprecated */
static inline bool __deprecated flush_delayed_work_sync(struct delayed_work *dwork)
{
	return flush_delayed_work(dwork);
}

#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>
60063497	13	#include <linux/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);
d8e794df	19	void delayed_work_timer_fn(unsigned long __data);
6bb49e59	20
a08727ba LT	21	/*
	22	* The first word is the work queue pointer and the flags rolled into
	23	* one
	24	*/
	25	#define work_data_bits(work) ((unsigned long *)(&(work)->data))
	26
22df02bb TH	27	enum {
22df02bb TH	28	WORK_STRUCT_PENDING_BIT = 0, /* work item is pending execution */
8a2e8e5d	29	WORK_STRUCT_DELAYED_BIT = 1, /* work item is delayed */
112202d9	30	WORK_STRUCT_PWQ_BIT = 2, /* data points to pwq */
8a2e8e5d	31	WORK_STRUCT_LINKED_BIT = 3, /* next work is linked to this one */
22df02bb	32	#ifdef CONFIG_DEBUG_OBJECTS_WORK
8a2e8e5d TH	33	WORK_STRUCT_STATIC_BIT = 4, /* static initializer (debugobjects) */
8a2e8e5d TH	34	WORK_STRUCT_COLOR_SHIFT = 5, /* color for workqueue flushing */
0f900049	35	#else
8a2e8e5d	36	WORK_STRUCT_COLOR_SHIFT = 4, /* color for workqueue flushing */
22df02bb TH	37	#endif
22df02bb TH	38
73f53c4a TH	39	WORK_STRUCT_COLOR_BITS = 4,
73f53c4a TH	40
22df02bb	41	WORK_STRUCT_PENDING = 1 << WORK_STRUCT_PENDING_BIT,
8a2e8e5d	42	WORK_STRUCT_DELAYED = 1 << WORK_STRUCT_DELAYED_BIT,
112202d9	43	WORK_STRUCT_PWQ = 1 << WORK_STRUCT_PWQ_BIT,
affee4b2	44	WORK_STRUCT_LINKED = 1 << WORK_STRUCT_LINKED_BIT,
22df02bb TH	45	#ifdef CONFIG_DEBUG_OBJECTS_WORK
	46	WORK_STRUCT_STATIC = 1 << WORK_STRUCT_STATIC_BIT,
	47	#else
	48	WORK_STRUCT_STATIC = 0,
	49	#endif
	50
73f53c4a TH	51	/*
	52	* The last color is no color used for works which don't
	53	* participate in workqueue flushing.
	54	*/
	55	WORK_NR_COLORS = (1 << WORK_STRUCT_COLOR_BITS) - 1,
	56	WORK_NO_COLOR = WORK_NR_COLORS,
	57
bdbc5dd7	58	/* special cpu IDs */
f3421797	59	WORK_CPU_UNBOUND = NR_CPUS,
6be19588	60	WORK_CPU_END = NR_CPUS + 1,
bdbc5dd7	61
73f53c4a	62	/*
112202d9 TH	63	* Reserve 7 bits off of pwq pointer w/ debugobjects turned off.
	64	* This makes pwqs aligned to 256 bytes and allows 15 workqueue
	65	* flush colors.
73f53c4a TH	66	*/
	67	WORK_STRUCT_FLAG_BITS = WORK_STRUCT_COLOR_SHIFT +
	68	WORK_STRUCT_COLOR_BITS,
	69
112202d9	70	/* data contains off-queue information when !WORK_STRUCT_PWQ */
45d9550a	71	WORK_OFFQ_FLAG_BASE = WORK_STRUCT_COLOR_SHIFT,
bbb68dfa TH	72
	73	WORK_OFFQ_CANCELING = (1 << WORK_OFFQ_FLAG_BASE),
	74
715b06b8 TH	75	/*
715b06b8 TH	76	* When a work item is off queue, its high bits point to the last
7c3eed5c TH	77	* pool it was on. Cap at 31 bits and use the highest number to
7c3eed5c TH	78	* indicate that no pool is associated.
715b06b8	79	*/
bbb68dfa	80	WORK_OFFQ_FLAG_BITS = 1,
7c3eed5c TH	81	WORK_OFFQ_POOL_SHIFT = WORK_OFFQ_FLAG_BASE + WORK_OFFQ_FLAG_BITS,
	82	WORK_OFFQ_LEFT = BITS_PER_LONG - WORK_OFFQ_POOL_SHIFT,
	83	WORK_OFFQ_POOL_BITS = WORK_OFFQ_LEFT <= 31 ? WORK_OFFQ_LEFT : 31,
	84	WORK_OFFQ_POOL_NONE = (1LU << WORK_OFFQ_POOL_BITS) - 1,
b5490077 TH	85
b5490077 TH	86	/* convenience constants */
0f900049	87	WORK_STRUCT_FLAG_MASK = (1UL << WORK_STRUCT_FLAG_BITS) - 1,
22df02bb	88	WORK_STRUCT_WQ_DATA_MASK = ~WORK_STRUCT_FLAG_MASK,
7c3eed5c	89	WORK_STRUCT_NO_POOL = (unsigned long)WORK_OFFQ_POOL_NONE << WORK_OFFQ_POOL_SHIFT,
dcd989cb TH	90
	91	/* bit mask for work_busy() return values */
	92	WORK_BUSY_PENDING = 1 << 0,
	93	WORK_BUSY_RUNNING = 1 << 1,
22df02bb TH	94	};
22df02bb TH	95
1da177e4	96	struct work_struct {
a08727ba	97	atomic_long_t data;
1da177e4	98	struct list_head entry;
6bb49e59	99	work_func_t func;
4e6045f1 JB	100	#ifdef CONFIG_LOCKDEP
	101	struct lockdep_map lockdep_map;
	102	#endif
52bad64d DH	103	};
52bad64d DH	104
7c3eed5c	105	#define WORK_DATA_INIT() ATOMIC_LONG_INIT(WORK_STRUCT_NO_POOL)
7a22ad75	106	#define WORK_DATA_STATIC_INIT() \
7c3eed5c	107	ATOMIC_LONG_INIT(WORK_STRUCT_NO_POOL \| WORK_STRUCT_STATIC)
a08727ba	108
52bad64d DH	109	struct delayed_work {
52bad64d DH	110	struct work_struct work;
1da177e4	111	struct timer_list timer;
60c057bc LJ	112
	113	/* target workqueue and CPU ->timer uses to queue ->work */
	114	struct workqueue_struct *wq;
1265057f	115	int cpu;
1da177e4 LT	116	};
1da177e4 LT	117
bf6aede7 JD	118	static inline struct delayed_work to_delayed_work(struct work_struct work)
	119	{
	120	return container_of(work, struct delayed_work, work);
	121	}
	122
1fa44eca JB	123	struct execute_work {
	124	struct work_struct work;
	125	};
	126
4e6045f1 JB	127	#ifdef CONFIG_LOCKDEP
	128	/*
	129	* NB: because we have to copy the lockdep_map, setting _key
	130	* here is required, otherwise it could get initialised to the
	131	* copy of the lockdep_map!
	132	*/
	133	#define __WORK_INIT_LOCKDEP_MAP(n, k) \
	134	.lockdep_map = STATIC_LOCKDEP_MAP_INIT(n, k),
	135	#else
	136	#define __WORK_INIT_LOCKDEP_MAP(n, k)
	137	#endif
	138
ee64e7f6 TH	139	#define __WORK_INITIALIZER(n, f) { \
	140	.data = WORK_DATA_STATIC_INIT(), \
	141	.entry = { &(n).entry, &(n).entry }, \
	142	.func = (f), \
	143	__WORK_INIT_LOCKDEP_MAP(#n, &(n)) \
65f27f38 DH	144	}
65f27f38 DH	145
f991b318	146	#define __DELAYED_WORK_INITIALIZER(n, f, tflags) { \
ee64e7f6	147	.work = __WORK_INITIALIZER((n).work, (f)), \
f991b318	148	.timer = __TIMER_INITIALIZER(delayed_work_timer_fn, \
e0aecdd8 TH	149	0, (unsigned long)&(n), \
e0aecdd8 TH	150	(tflags) \| TIMER_IRQSAFE), \
dd6414b5 PC	151	}
dd6414b5 PC	152
ee64e7f6	153	#define DECLARE_WORK(n, f) \
65f27f38 DH	154	struct work_struct n = __WORK_INITIALIZER(n, f)
65f27f38 DH	155
ee64e7f6	156	#define DECLARE_DELAYED_WORK(n, f) \
f991b318	157	struct delayed_work n = __DELAYED_WORK_INITIALIZER(n, f, 0)
65f27f38	158
203b42f7	159	#define DECLARE_DEFERRABLE_WORK(n, f) \
f991b318	160	struct delayed_work n = __DELAYED_WORK_INITIALIZER(n, f, TIMER_DEFERRABLE)
dd6414b5	161
1da177e4	162	/*
65f27f38	163	* initialize a work item's function pointer
1da177e4	164	*/
ee64e7f6 TH	165	#define PREPARE_WORK(_work, _func) \
	166	do { \
	167	(_work)->func = (_func); \
1da177e4 LT	168	} while (0)
1da177e4 LT	169
ee64e7f6	170	#define PREPARE_DELAYED_WORK(_work, _func) \
65f27f38	171	PREPARE_WORK(&(_work)->work, (_func))
52bad64d	172
dc186ad7 TG	173	#ifdef CONFIG_DEBUG_OBJECTS_WORK
	174	extern void __init_work(struct work_struct *work, int onstack);
	175	extern void destroy_work_on_stack(struct work_struct *work);
4690c4ab TH	176	static inline unsigned int work_static(struct work_struct *work)
4690c4ab TH	177	{
22df02bb	178	return *work_data_bits(work) & WORK_STRUCT_STATIC;
4690c4ab	179	}
dc186ad7 TG	180	#else
	181	static inline void __init_work(struct work_struct *work, int onstack) { }
	182	static inline void destroy_work_on_stack(struct work_struct *work) { }
4690c4ab	183	static inline unsigned int work_static(struct work_struct *work) { return 0; }
dc186ad7 TG	184	#endif
dc186ad7 TG	185
1da177e4	186	/*
52bad64d	187	* initialize all of a work item in one go
a08727ba	188	*
b9049df5	189	* NOTE! No point in using "atomic_long_set()": using a direct
a08727ba LT	190	* assignment of the work data initializer allows the compiler
a08727ba LT	191	* to generate better code.
1da177e4	192	*/
4e6045f1	193	#ifdef CONFIG_LOCKDEP
dc186ad7	194	#define __INIT_WORK(_work, _func, _onstack) \
65f27f38	195	do { \
4e6045f1 JB	196	static struct lock_class_key __key; \
4e6045f1 JB	197	\
dc186ad7	198	__init_work((_work), _onstack); \
23b2e599	199	(_work)->data = (atomic_long_t) WORK_DATA_INIT(); \
ee64e7f6	200	lockdep_init_map(&(_work)->lockdep_map, #_work, &__key, 0); \
65f27f38 DH	201	INIT_LIST_HEAD(&(_work)->entry); \
	202	PREPARE_WORK((_work), (_func)); \
	203	} while (0)
4e6045f1	204	#else
dc186ad7	205	#define __INIT_WORK(_work, _func, _onstack) \
4e6045f1	206	do { \
dc186ad7	207	__init_work((_work), _onstack); \
4e6045f1 JB	208	(_work)->data = (atomic_long_t) WORK_DATA_INIT(); \
	209	INIT_LIST_HEAD(&(_work)->entry); \
	210	PREPARE_WORK((_work), (_func)); \
	211	} while (0)
	212	#endif
65f27f38	213
ee64e7f6 TH	214	#define INIT_WORK(_work, _func) \
	215	do { \
	216	__INIT_WORK((_work), (_func), 0); \
dc186ad7 TG	217	} while (0)
dc186ad7 TG	218
ee64e7f6 TH	219	#define INIT_WORK_ONSTACK(_work, _func) \
	220	do { \
	221	__INIT_WORK((_work), (_func), 1); \
dc186ad7 TG	222	} while (0)
dc186ad7 TG	223
f991b318	224	#define __INIT_DELAYED_WORK(_work, _func, _tflags) \
ee64e7f6 TH	225	do { \
ee64e7f6 TH	226	INIT_WORK(&(_work)->work, (_func)); \
f991b318	227	__setup_timer(&(_work)->timer, delayed_work_timer_fn, \
e0aecdd8 TH	228	(unsigned long)(_work), \
e0aecdd8 TH	229	(_tflags) \| TIMER_IRQSAFE); \
52bad64d DH	230	} while (0)
52bad64d DH	231
f991b318	232	#define __INIT_DELAYED_WORK_ONSTACK(_work, _func, _tflags) \
ee64e7f6 TH	233	do { \
ee64e7f6 TH	234	INIT_WORK_ONSTACK(&(_work)->work, (_func)); \
f991b318 TH	235	__setup_timer_on_stack(&(_work)->timer, \
	236	delayed_work_timer_fn, \
	237	(unsigned long)(_work), \
e0aecdd8	238	(_tflags) \| TIMER_IRQSAFE); \
6d612b0f PZ	239	} while (0)
6d612b0f PZ	240
f991b318 TH	241	#define INIT_DELAYED_WORK(_work, _func) \
	242	__INIT_DELAYED_WORK(_work, _func, 0)
	243
	244	#define INIT_DELAYED_WORK_ONSTACK(_work, _func) \
	245	__INIT_DELAYED_WORK_ONSTACK(_work, _func, 0)
	246
203b42f7	247	#define INIT_DEFERRABLE_WORK(_work, _func) \
f991b318 TH	248	__INIT_DELAYED_WORK(_work, _func, TIMER_DEFERRABLE)
	249
	250	#define INIT_DEFERRABLE_WORK_ONSTACK(_work, _func) \
	251	__INIT_DELAYED_WORK_ONSTACK(_work, _func, TIMER_DEFERRABLE)
28287033	252
365970a1 DH	253	/**
	254	* work_pending - Find out whether a work item is currently pending
	255	* @work: The work item in question
	256	*/
	257	#define work_pending(work) \
22df02bb	258	test_bit(WORK_STRUCT_PENDING_BIT, work_data_bits(work))
365970a1 DH	259
	260	/**
	261	* delayed_work_pending - Find out whether a delayable work item is currently
	262	* pending
	263	* @work: The work item in question
	264	*/
0221872a LT	265	#define delayed_work_pending(w) \
0221872a LT	266	work_pending(&(w)->work)
365970a1	267
65f27f38	268	/**
23b2e599 ON	269	* work_clear_pending - for internal use only, mark a work item as not pending
23b2e599 ON	270	* @work: The work item in question
65f27f38	271	*/
23b2e599	272	#define work_clear_pending(work) \
22df02bb	273	clear_bit(WORK_STRUCT_PENDING_BIT, work_data_bits(work))
65f27f38	274
c54fce6e TH	275	/*
	276	* Workqueue flags and constants. For details, please refer to
	277	* Documentation/workqueue.txt.
	278	*/
97e37d7b	279	enum {
bdbc5dd7	280	WQ_NON_REENTRANT = 1 << 0, /* guarantee non-reentrance */
c7fc77f7	281	WQ_UNBOUND = 1 << 1, /* not bound to any cpu */
58a69cb4	282	WQ_FREEZABLE = 1 << 2, /* freeze during suspend */
6370a6ad	283	WQ_MEM_RECLAIM = 1 << 3, /* may be used for memory reclaim */
649027d7	284	WQ_HIGHPRI = 1 << 4, /* high priority */
fb0e7beb	285	WQ_CPU_INTENSIVE = 1 << 5, /* cpu instensive workqueue */
b71ab8c2	286
9c5a2ba7	287	WQ_DRAINING = 1 << 6, /* internal: workqueue is draining */
6370a6ad	288	WQ_RESCUER = 1 << 7, /* internal: workqueue has rescuer */
e41e704b	289
b71ab8c2	290	WQ_MAX_ACTIVE = 512, /* I like 512, better ideas? */
f3421797	291	WQ_MAX_UNBOUND_PER_CPU = 4, /* 4 * #cpus for unbound wq */
b71ab8c2	292	WQ_DFL_ACTIVE = WQ_MAX_ACTIVE / 2,
97e37d7b	293	};
52bad64d	294
f3421797 TH	295	/* unbound wq's aren't per-cpu, scale max_active according to #cpus */
	296	#define WQ_UNBOUND_MAX_ACTIVE \
	297	max_t(int, WQ_MAX_ACTIVE, num_possible_cpus() * WQ_MAX_UNBOUND_PER_CPU)
65f27f38	298
d320c038 TH	299	/*
	300	* System-wide workqueues which are always present.
	301	*
	302	* system_wq is the one used by schedule[_delayed]_work[_on]().
	303	* Multi-CPU multi-threaded. There are users which expect relatively
	304	* short queue flush time. Don't queue works which can run for too
	305	* long.
	306	*
	307	* system_long_wq is similar to system_wq but may host long running
	308	* works. Queue flushing might take relatively long.
	309	*
f3421797 TH	310	* system_unbound_wq is unbound workqueue. Workers are not bound to
	311	* any specific CPU, not concurrency managed, and all queued works are
	312	* executed immediately as long as max_active limit is not reached and
	313	* resources are available.
4149efb2	314	*
24d51add TH	315	* system_freezable_wq is equivalent to system_wq except that it's
24d51add TH	316	* freezable.
d320c038 TH	317	*/
	318	extern struct workqueue_struct *system_wq;
	319	extern struct workqueue_struct *system_long_wq;
f3421797	320	extern struct workqueue_struct *system_unbound_wq;
24d51add	321	extern struct workqueue_struct *system_freezable_wq;
ae930e0f	322
3b07e9ca	323	static inline struct workqueue_struct * __deprecated __system_nrt_wq(void)
ae930e0f TH	324	{
	325	return system_wq;
	326	}
	327
3b07e9ca	328	static inline struct workqueue_struct * __deprecated __system_nrt_freezable_wq(void)
ae930e0f TH	329	{
	330	return system_freezable_wq;
	331	}
	332
	333	/* equivlalent to system_wq and system_freezable_wq, deprecated */
	334	#define system_nrt_wq __system_nrt_wq()
	335	#define system_nrt_freezable_wq __system_nrt_freezable_wq()
52bad64d	336
4e6045f1	337	extern struct workqueue_struct *
b196be89 TH	338	__alloc_workqueue_key(const char *fmt, unsigned int flags, int max_active,
b196be89 TH	339	struct lock_class_key key, const char lock_name, ...) __printf(1, 6);
4e6045f1	340
b196be89 TH	341	/**
	342	* alloc_workqueue - allocate a workqueue
	343	* @fmt: printf format for the name of the workqueue
	344	* @flags: WQ_* flags
	345	* @max_active: max in-flight work items, 0 for default
	346	* @args: args for @fmt
	347	*
	348	* Allocate a workqueue with the specified parameters. For detailed
	349	* information on WQ_* flags, please refer to Documentation/workqueue.txt.
	350	*
	351	* The __lock_name macro dance is to guarantee that single lock_class_key
	352	* doesn't end up with different namesm, which isn't allowed by lockdep.
	353	*
	354	* RETURNS:
	355	* Pointer to the allocated workqueue on success, %NULL on failure.
	356	*/
4e6045f1	357	#ifdef CONFIG_LOCKDEP
ee64e7f6 TH	358	#define alloc_workqueue(fmt, flags, max_active, args...) \
	359	({ \
	360	static struct lock_class_key __key; \
	361	const char *__lock_name; \
	362	\
	363	if (__builtin_constant_p(fmt)) \
	364	__lock_name = (fmt); \
	365	else \
	366	__lock_name = #fmt; \
	367	\
	368	__alloc_workqueue_key((fmt), (flags), (max_active), \
	369	&__key, __lock_name, ##args); \
4e6045f1 JB	370	})
4e6045f1 JB	371	#else
ee64e7f6 TH	372	#define alloc_workqueue(fmt, flags, max_active, args...) \
ee64e7f6 TH	373	__alloc_workqueue_key((fmt), (flags), (max_active), \
b196be89	374	NULL, NULL, ##args)
4e6045f1 JB	375	#endif
4e6045f1 JB	376
81dcaf65 TH	377	/**
81dcaf65 TH	378	* alloc_ordered_workqueue - allocate an ordered workqueue
b196be89	379	* @fmt: printf format for the name of the workqueue
58a69cb4	380	* @flags: WQ_* flags (only WQ_FREEZABLE and WQ_MEM_RECLAIM are meaningful)
b196be89	381	* @args: args for @fmt
81dcaf65 TH	382	*
	383	* Allocate an ordered workqueue. An ordered workqueue executes at
	384	* most one work item at any given time in the queued order. They are
	385	* implemented as unbound workqueues with @max_active of one.
	386	*
	387	* RETURNS:
	388	* Pointer to the allocated workqueue on success, %NULL on failure.
	389	*/
ee64e7f6	390	#define alloc_ordered_workqueue(fmt, flags, args...) \
b196be89	391	alloc_workqueue(fmt, WQ_UNBOUND \| (flags), 1, ##args)
81dcaf65	392
ee64e7f6	393	#define create_workqueue(name) \
6370a6ad	394	alloc_workqueue((name), WQ_MEM_RECLAIM, 1)
ee64e7f6	395	#define create_freezable_workqueue(name) \
58a69cb4	396	alloc_workqueue((name), WQ_FREEZABLE \| WQ_UNBOUND \| WQ_MEM_RECLAIM, 1)
ee64e7f6	397	#define create_singlethread_workqueue(name) \
6370a6ad	398	alloc_workqueue((name), WQ_UNBOUND \| WQ_MEM_RECLAIM, 1)
1da177e4 LT	399
	400	extern void destroy_workqueue(struct workqueue_struct *wq);
	401
d4283e93	402	extern bool queue_work_on(int cpu, struct workqueue_struct *wq,
c1a220e7	403	struct work_struct *work);
d4283e93 TH	404	extern bool queue_work(struct workqueue_struct wq, struct work_struct work);
d4283e93 TH	405	extern bool queue_delayed_work_on(int cpu, struct workqueue_struct *wq,
28e53bdd	406	struct delayed_work *work, unsigned long delay);
d4283e93	407	extern bool queue_delayed_work(struct workqueue_struct *wq,
0a13c00e	408	struct delayed_work *work, unsigned long delay);
8376fe22 TH	409	extern bool mod_delayed_work_on(int cpu, struct workqueue_struct *wq,
	410	struct delayed_work *dwork, unsigned long delay);
	411	extern bool mod_delayed_work(struct workqueue_struct *wq,
	412	struct delayed_work *dwork, unsigned long delay);
28e53bdd	413
b3c97528	414	extern void flush_workqueue(struct workqueue_struct *wq);
9c5a2ba7	415	extern void drain_workqueue(struct workqueue_struct *wq);
28e53bdd	416	extern void flush_scheduled_work(void);
1da177e4	417
d4283e93 TH	418	extern bool schedule_work_on(int cpu, struct work_struct *work);
	419	extern bool schedule_work(struct work_struct *work);
	420	extern bool schedule_delayed_work_on(int cpu, struct delayed_work *work,
	421	unsigned long delay);
	422	extern bool schedule_delayed_work(struct delayed_work *work,
	423	unsigned long delay);
65f27f38	424	extern int schedule_on_each_cpu(work_func_t func);
1da177e4 LT	425	extern int keventd_up(void);
1da177e4 LT	426
65f27f38	427	int execute_in_process_context(work_func_t fn, struct execute_work *);
1da177e4	428
401a8d04 TH	429	extern bool flush_work(struct work_struct *work);
	430	extern bool cancel_work_sync(struct work_struct *work);
	431
	432	extern bool flush_delayed_work(struct delayed_work *dwork);
57b30ae7	433	extern bool cancel_delayed_work(struct delayed_work *dwork);
401a8d04	434	extern bool cancel_delayed_work_sync(struct delayed_work *dwork);
28e53bdd	435
dcd989cb TH	436	extern void workqueue_set_max_active(struct workqueue_struct *wq,
	437	int max_active);
	438	extern bool workqueue_congested(unsigned int cpu, struct workqueue_struct *wq);
dcd989cb TH	439	extern unsigned int work_busy(struct work_struct *work);
dcd989cb TH	440
4e49627b ON	441	/*
	442	* Like above, but uses del_timer() instead of del_timer_sync(). This means,
	443	* if it returns 0 the timer function may be running and the queueing is in
	444	* progress.
	445	*/
136b5721	446	static inline bool __deprecated __cancel_delayed_work(struct delayed_work *work)
4e49627b	447	{
401a8d04	448	bool ret;
4e49627b ON	449
	450	ret = del_timer(&work->timer);
	451	if (ret)
	452	work_clear_pending(&work->work);
	453	return ret;
	454	}
	455
606a5020	456	/* used to be different but now identical to flush_work(), deprecated */
43829731	457	static inline bool __deprecated flush_work_sync(struct work_struct *work)
606a5020 TH	458	{
	459	return flush_work(work);
	460	}
	461
	462	/* used to be different but now identical to flush_delayed_work(), deprecated */
43829731	463	static inline bool __deprecated flush_delayed_work_sync(struct delayed_work *dwork)
606a5020 TH	464	{
	465	return flush_delayed_work(dwork);
	466	}
	467
2d3854a3 RR	468	#ifndef CONFIG_SMP
	469	static inline long work_on_cpu(unsigned int cpu, long (fn)(void ), void *arg)
	470	{
	471	return fn(arg);
	472	}
	473	#else
	474	long work_on_cpu(unsigned int cpu, long (fn)(void ), void *arg);
	475	#endif /* CONFIG_SMP */
a25909a4	476
a0a1a5fd TH	477	#ifdef CONFIG_FREEZER
	478	extern void freeze_workqueues_begin(void);
	479	extern bool freeze_workqueues_busy(void);
	480	extern void thaw_workqueues(void);
	481	#endif /* CONFIG_FREEZER */
	482
1da177e4	483	#endif