[GitHub/mt8127/android_kernel_alcatel_ttab.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);

/*
 * 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_CWQ_BIT	= 2,	/* data points to cwq */
	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_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 256 bytes and allows 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 __DEFERRED_WORK_INITIALIZER(n, f) {			\
	.work = __WORK_INITIALIZER((n).work, (f)),		\
	.timer = TIMER_DEFERRED_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)

#define DECLARE_DEFERRED_WORK(n, f)				\
	struct delayed_work n = __DEFERRED_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_ONSTACK(_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_ONSTACK(_work, _func)			\
	do {							\
		INIT_WORK_ONSTACK(&(_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))

/*
 * 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_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.
 *
 * 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_nrt_wq;
extern struct workqueue_struct *system_unbound_wq;
extern struct workqueue_struct *system_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 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 drain_workqueue(struct workqueue_struct *wq);
extern void flush_scheduled_work(void);

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 bool flush_work(struct work_struct *work);
extern bool flush_work_sync(struct work_struct *work);
extern bool cancel_work_sync(struct work_struct *work);

extern bool flush_delayed_work(struct delayed_work *dwork);
extern bool flush_delayed_work_sync(struct delayed_work *work);
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_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 bool cancel_delayed_work(struct delayed_work *work)
{
	bool 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 bool __cancel_delayed_work(struct delayed_work *work)
{
	bool ret;

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

#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);
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 */
8a2e8e5d TH	28	WORK_STRUCT_DELAYED_BIT = 1, /* work item is delayed */
	29	WORK_STRUCT_CWQ_BIT = 2, /* data points to cwq */
	30	WORK_STRUCT_LINKED_BIT = 3, /* next work is linked to this one */
22df02bb	31	#ifdef CONFIG_DEBUG_OBJECTS_WORK
8a2e8e5d TH	32	WORK_STRUCT_STATIC_BIT = 4, /* static initializer (debugobjects) */
8a2e8e5d TH	33	WORK_STRUCT_COLOR_SHIFT = 5, /* color for workqueue flushing */
0f900049	34	#else
8a2e8e5d	35	WORK_STRUCT_COLOR_SHIFT = 4, /* color for workqueue flushing */
22df02bb TH	36	#endif
22df02bb TH	37
73f53c4a TH	38	WORK_STRUCT_COLOR_BITS = 4,
73f53c4a TH	39
22df02bb	40	WORK_STRUCT_PENDING = 1 << WORK_STRUCT_PENDING_BIT,
8a2e8e5d	41	WORK_STRUCT_DELAYED = 1 << WORK_STRUCT_DELAYED_BIT,
e120153d	42	WORK_STRUCT_CWQ = 1 << WORK_STRUCT_CWQ_BIT,
affee4b2	43	WORK_STRUCT_LINKED = 1 << WORK_STRUCT_LINKED_BIT,
22df02bb TH	44	#ifdef CONFIG_DEBUG_OBJECTS_WORK
	45	WORK_STRUCT_STATIC = 1 << WORK_STRUCT_STATIC_BIT,
	46	#else
	47	WORK_STRUCT_STATIC = 0,
	48	#endif
	49
73f53c4a TH	50	/*
	51	* The last color is no color used for works which don't
	52	* participate in workqueue flushing.
	53	*/
	54	WORK_NR_COLORS = (1 << WORK_STRUCT_COLOR_BITS) - 1,
	55	WORK_NO_COLOR = WORK_NR_COLORS,
	56
bdbc5dd7	57	/* special cpu IDs */
f3421797 TH	58	WORK_CPU_UNBOUND = NR_CPUS,
f3421797 TH	59	WORK_CPU_NONE = NR_CPUS + 1,
bdbc5dd7 TH	60	WORK_CPU_LAST = WORK_CPU_NONE,
bdbc5dd7 TH	61
73f53c4a	62	/*
e120153d	63	* Reserve 7 bits off of cwq pointer w/ debugobjects turned
8a2e8e5d TH	64	* off. This makes cwqs aligned to 256 bytes and allows 15
8a2e8e5d TH	65	* workqueue flush colors.
73f53c4a TH	66	*/
	67	WORK_STRUCT_FLAG_BITS = WORK_STRUCT_COLOR_SHIFT +
	68	WORK_STRUCT_COLOR_BITS,
	69
0f900049	70	WORK_STRUCT_FLAG_MASK = (1UL << WORK_STRUCT_FLAG_BITS) - 1,
22df02bb	71	WORK_STRUCT_WQ_DATA_MASK = ~WORK_STRUCT_FLAG_MASK,
bdbc5dd7	72	WORK_STRUCT_NO_CPU = WORK_CPU_NONE << WORK_STRUCT_FLAG_BITS,
dcd989cb TH	73
	74	/* bit mask for work_busy() return values */
	75	WORK_BUSY_PENDING = 1 << 0,
	76	WORK_BUSY_RUNNING = 1 << 1,
22df02bb TH	77	};
22df02bb TH	78
1da177e4	79	struct work_struct {
a08727ba	80	atomic_long_t data;
1da177e4	81	struct list_head entry;
6bb49e59	82	work_func_t func;
4e6045f1 JB	83	#ifdef CONFIG_LOCKDEP
	84	struct lockdep_map lockdep_map;
	85	#endif
52bad64d DH	86	};
52bad64d DH	87
7a22ad75 TH	88	#define WORK_DATA_INIT() ATOMIC_LONG_INIT(WORK_STRUCT_NO_CPU)
	89	#define WORK_DATA_STATIC_INIT() \
	90	ATOMIC_LONG_INIT(WORK_STRUCT_NO_CPU \| WORK_STRUCT_STATIC)
a08727ba	91
52bad64d DH	92	struct delayed_work {
52bad64d DH	93	struct work_struct work;
1da177e4 LT	94	struct timer_list timer;
	95	};
	96
bf6aede7 JD	97	static inline struct delayed_work to_delayed_work(struct work_struct work)
	98	{
	99	return container_of(work, struct delayed_work, work);
	100	}
	101
1fa44eca JB	102	struct execute_work {
	103	struct work_struct work;
	104	};
	105
4e6045f1 JB	106	#ifdef CONFIG_LOCKDEP
	107	/*
	108	* NB: because we have to copy the lockdep_map, setting _key
	109	* here is required, otherwise it could get initialised to the
	110	* copy of the lockdep_map!
	111	*/
	112	#define __WORK_INIT_LOCKDEP_MAP(n, k) \
	113	.lockdep_map = STATIC_LOCKDEP_MAP_INIT(n, k),
	114	#else
	115	#define __WORK_INIT_LOCKDEP_MAP(n, k)
	116	#endif
	117
65f27f38	118	#define __WORK_INITIALIZER(n, f) { \
dc186ad7	119	.data = WORK_DATA_STATIC_INIT(), \
23b2e599	120	.entry = { &(n).entry, &(n).entry }, \
65f27f38	121	.func = (f), \
4e6045f1	122	__WORK_INIT_LOCKDEP_MAP(#n, &(n)) \
65f27f38 DH	123	}
	124
	125	#define __DELAYED_WORK_INITIALIZER(n, f) { \
	126	.work = __WORK_INITIALIZER((n).work, (f)), \
	127	.timer = TIMER_INITIALIZER(NULL, 0, 0), \
	128	}
	129
dd6414b5 PC	130	#define __DEFERRED_WORK_INITIALIZER(n, f) { \
	131	.work = __WORK_INITIALIZER((n).work, (f)), \
	132	.timer = TIMER_DEFERRED_INITIALIZER(NULL, 0, 0), \
	133	}
	134
65f27f38 DH	135	#define DECLARE_WORK(n, f) \
	136	struct work_struct n = __WORK_INITIALIZER(n, f)
	137
65f27f38 DH	138	#define DECLARE_DELAYED_WORK(n, f) \
	139	struct delayed_work n = __DELAYED_WORK_INITIALIZER(n, f)
	140
dd6414b5 PC	141	#define DECLARE_DEFERRED_WORK(n, f) \
	142	struct delayed_work n = __DEFERRED_WORK_INITIALIZER(n, f)
	143
1da177e4	144	/*
65f27f38	145	* initialize a work item's function pointer
1da177e4	146	*/
65f27f38	147	#define PREPARE_WORK(_work, _func) \
1da177e4	148	do { \
52bad64d	149	(_work)->func = (_func); \
1da177e4 LT	150	} while (0)
1da177e4 LT	151
65f27f38 DH	152	#define PREPARE_DELAYED_WORK(_work, _func) \
65f27f38 DH	153	PREPARE_WORK(&(_work)->work, (_func))
52bad64d	154
dc186ad7 TG	155	#ifdef CONFIG_DEBUG_OBJECTS_WORK
	156	extern void __init_work(struct work_struct *work, int onstack);
	157	extern void destroy_work_on_stack(struct work_struct *work);
4690c4ab TH	158	static inline unsigned int work_static(struct work_struct *work)
4690c4ab TH	159	{
22df02bb	160	return *work_data_bits(work) & WORK_STRUCT_STATIC;
4690c4ab	161	}
dc186ad7 TG	162	#else
	163	static inline void __init_work(struct work_struct *work, int onstack) { }
	164	static inline void destroy_work_on_stack(struct work_struct *work) { }
4690c4ab	165	static inline unsigned int work_static(struct work_struct *work) { return 0; }
dc186ad7 TG	166	#endif
dc186ad7 TG	167
1da177e4	168	/*
52bad64d	169	* initialize all of a work item in one go
a08727ba	170	*
b9049df5	171	* NOTE! No point in using "atomic_long_set()": using a direct
a08727ba LT	172	* assignment of the work data initializer allows the compiler
a08727ba LT	173	* to generate better code.
1da177e4	174	*/
4e6045f1	175	#ifdef CONFIG_LOCKDEP
dc186ad7	176	#define __INIT_WORK(_work, _func, _onstack) \
65f27f38	177	do { \
4e6045f1 JB	178	static struct lock_class_key __key; \
4e6045f1 JB	179	\
dc186ad7	180	__init_work((_work), _onstack); \
23b2e599	181	(_work)->data = (atomic_long_t) WORK_DATA_INIT(); \
4e6045f1	182	lockdep_init_map(&(_work)->lockdep_map, #_work, &__key, 0);\
65f27f38 DH	183	INIT_LIST_HEAD(&(_work)->entry); \
	184	PREPARE_WORK((_work), (_func)); \
	185	} while (0)
4e6045f1	186	#else
dc186ad7	187	#define __INIT_WORK(_work, _func, _onstack) \
4e6045f1	188	do { \
dc186ad7	189	__init_work((_work), _onstack); \
4e6045f1 JB	190	(_work)->data = (atomic_long_t) WORK_DATA_INIT(); \
	191	INIT_LIST_HEAD(&(_work)->entry); \
	192	PREPARE_WORK((_work), (_func)); \
	193	} while (0)
	194	#endif
65f27f38	195
dc186ad7 TG	196	#define INIT_WORK(_work, _func) \
	197	do { \
	198	__INIT_WORK((_work), (_func), 0); \
	199	} while (0)
	200
ca1cab37	201	#define INIT_WORK_ONSTACK(_work, _func) \
dc186ad7 TG	202	do { \
	203	__INIT_WORK((_work), (_func), 1); \
	204	} while (0)
	205
65f27f38 DH	206	#define INIT_DELAYED_WORK(_work, _func) \
	207	do { \
	208	INIT_WORK(&(_work)->work, (_func)); \
	209	init_timer(&(_work)->timer); \
52bad64d DH	210	} while (0)
52bad64d DH	211
ca1cab37	212	#define INIT_DELAYED_WORK_ONSTACK(_work, _func) \
6d612b0f	213	do { \
ca1cab37	214	INIT_WORK_ONSTACK(&(_work)->work, (_func)); \
6d612b0f PZ	215	init_timer_on_stack(&(_work)->timer); \
	216	} while (0)
	217
dc186ad7	218	#define INIT_DELAYED_WORK_DEFERRABLE(_work, _func) \
28287033 VP	219	do { \
	220	INIT_WORK(&(_work)->work, (_func)); \
	221	init_timer_deferrable(&(_work)->timer); \
	222	} while (0)
	223
365970a1 DH	224	/**
	225	* work_pending - Find out whether a work item is currently pending
	226	* @work: The work item in question
	227	*/
	228	#define work_pending(work) \
22df02bb	229	test_bit(WORK_STRUCT_PENDING_BIT, work_data_bits(work))
365970a1 DH	230
	231	/**
	232	* delayed_work_pending - Find out whether a delayable work item is currently
	233	* pending
	234	* @work: The work item in question
	235	*/
0221872a LT	236	#define delayed_work_pending(w) \
0221872a LT	237	work_pending(&(w)->work)
365970a1	238
65f27f38	239	/**
23b2e599 ON	240	* work_clear_pending - for internal use only, mark a work item as not pending
23b2e599 ON	241	* @work: The work item in question
65f27f38	242	*/
23b2e599	243	#define work_clear_pending(work) \
22df02bb	244	clear_bit(WORK_STRUCT_PENDING_BIT, work_data_bits(work))
65f27f38	245
c54fce6e TH	246	/*
	247	* Workqueue flags and constants. For details, please refer to
	248	* Documentation/workqueue.txt.
	249	*/
97e37d7b	250	enum {
bdbc5dd7	251	WQ_NON_REENTRANT = 1 << 0, /* guarantee non-reentrance */
c7fc77f7	252	WQ_UNBOUND = 1 << 1, /* not bound to any cpu */
58a69cb4	253	WQ_FREEZABLE = 1 << 2, /* freeze during suspend */
6370a6ad	254	WQ_MEM_RECLAIM = 1 << 3, /* may be used for memory reclaim */
649027d7	255	WQ_HIGHPRI = 1 << 4, /* high priority */
fb0e7beb	256	WQ_CPU_INTENSIVE = 1 << 5, /* cpu instensive workqueue */
b71ab8c2	257
9c5a2ba7	258	WQ_DRAINING = 1 << 6, /* internal: workqueue is draining */
6370a6ad	259	WQ_RESCUER = 1 << 7, /* internal: workqueue has rescuer */
e41e704b	260
b71ab8c2	261	WQ_MAX_ACTIVE = 512, /* I like 512, better ideas? */
f3421797	262	WQ_MAX_UNBOUND_PER_CPU = 4, /* 4 * #cpus for unbound wq */
b71ab8c2	263	WQ_DFL_ACTIVE = WQ_MAX_ACTIVE / 2,
97e37d7b	264	};
52bad64d	265
f3421797 TH	266	/* unbound wq's aren't per-cpu, scale max_active according to #cpus */
	267	#define WQ_UNBOUND_MAX_ACTIVE \
	268	max_t(int, WQ_MAX_ACTIVE, num_possible_cpus() * WQ_MAX_UNBOUND_PER_CPU)
65f27f38	269
d320c038 TH	270	/*
	271	* System-wide workqueues which are always present.
	272	*
	273	* system_wq is the one used by schedule[_delayed]_work[_on]().
	274	* Multi-CPU multi-threaded. There are users which expect relatively
	275	* short queue flush time. Don't queue works which can run for too
	276	* long.
	277	*
	278	* system_long_wq is similar to system_wq but may host long running
	279	* works. Queue flushing might take relatively long.
	280	*
	281	* system_nrt_wq is non-reentrant and guarantees that any given work
	282	* item is never executed in parallel by multiple CPUs. Queue
	283	* flushing might take relatively long.
f3421797 TH	284	*
	285	* system_unbound_wq is unbound workqueue. Workers are not bound to
	286	* any specific CPU, not concurrency managed, and all queued works are
	287	* executed immediately as long as max_active limit is not reached and
	288	* resources are available.
4149efb2	289	*
24d51add TH	290	* system_freezable_wq is equivalent to system_wq except that it's
24d51add TH	291	* freezable.
d320c038 TH	292	*/
	293	extern struct workqueue_struct *system_wq;
	294	extern struct workqueue_struct *system_long_wq;
	295	extern struct workqueue_struct *system_nrt_wq;
f3421797	296	extern struct workqueue_struct *system_unbound_wq;
24d51add	297	extern struct workqueue_struct *system_freezable_wq;
52bad64d	298
4e6045f1	299	extern struct workqueue_struct *
b196be89 TH	300	__alloc_workqueue_key(const char *fmt, unsigned int flags, int max_active,
b196be89 TH	301	struct lock_class_key key, const char lock_name, ...) __printf(1, 6);
4e6045f1	302
b196be89 TH	303	/**
	304	* alloc_workqueue - allocate a workqueue
	305	* @fmt: printf format for the name of the workqueue
	306	* @flags: WQ_* flags
	307	* @max_active: max in-flight work items, 0 for default
	308	* @args: args for @fmt
	309	*
	310	* Allocate a workqueue with the specified parameters. For detailed
	311	* information on WQ_* flags, please refer to Documentation/workqueue.txt.
	312	*
	313	* The __lock_name macro dance is to guarantee that single lock_class_key
	314	* doesn't end up with different namesm, which isn't allowed by lockdep.
	315	*
	316	* RETURNS:
	317	* Pointer to the allocated workqueue on success, %NULL on failure.
	318	*/
4e6045f1	319	#ifdef CONFIG_LOCKDEP
b196be89	320	#define alloc_workqueue(fmt, flags, max_active, args...) \
4e6045f1 JB	321	({ \
4e6045f1 JB	322	static struct lock_class_key __key; \
eb13ba87 JB	323	const char *__lock_name; \
eb13ba87 JB	324	\
b196be89 TH	325	if (__builtin_constant_p(fmt)) \
b196be89 TH	326	__lock_name = (fmt); \
eb13ba87	327	else \
b196be89	328	__lock_name = #fmt; \
4e6045f1	329	\
b196be89 TH	330	__alloc_workqueue_key((fmt), (flags), (max_active), \
b196be89 TH	331	&__key, __lock_name, ##args); \
4e6045f1 JB	332	})
4e6045f1 JB	333	#else
b196be89 TH	334	#define alloc_workqueue(fmt, flags, max_active, args...) \
	335	__alloc_workqueue_key((fmt), (flags), (max_active), \
	336	NULL, NULL, ##args)
4e6045f1 JB	337	#endif
4e6045f1 JB	338
81dcaf65 TH	339	/**
81dcaf65 TH	340	* alloc_ordered_workqueue - allocate an ordered workqueue
b196be89	341	* @fmt: printf format for the name of the workqueue
58a69cb4	342	* @flags: WQ_* flags (only WQ_FREEZABLE and WQ_MEM_RECLAIM are meaningful)
b196be89	343	* @args: args for @fmt
81dcaf65 TH	344	*
	345	* Allocate an ordered workqueue. An ordered workqueue executes at
	346	* most one work item at any given time in the queued order. They are
	347	* implemented as unbound workqueues with @max_active of one.
	348	*
	349	* RETURNS:
	350	* Pointer to the allocated workqueue on success, %NULL on failure.
	351	*/
b196be89 TH	352	#define alloc_ordered_workqueue(fmt, flags, args...) \
b196be89 TH	353	alloc_workqueue(fmt, WQ_UNBOUND \| (flags), 1, ##args)
81dcaf65	354
97e37d7b	355	#define create_workqueue(name) \
6370a6ad	356	alloc_workqueue((name), WQ_MEM_RECLAIM, 1)
58a69cb4 TH	357	#define create_freezable_workqueue(name) \
58a69cb4 TH	358	alloc_workqueue((name), WQ_FREEZABLE \| WQ_UNBOUND \| WQ_MEM_RECLAIM, 1)
97e37d7b	359	#define create_singlethread_workqueue(name) \
6370a6ad	360	alloc_workqueue((name), WQ_UNBOUND \| WQ_MEM_RECLAIM, 1)
1da177e4 LT	361
	362	extern void destroy_workqueue(struct workqueue_struct *wq);
	363
b3c97528	364	extern int queue_work(struct workqueue_struct wq, struct work_struct work);
c1a220e7 ZR	365	extern int queue_work_on(int cpu, struct workqueue_struct *wq,
c1a220e7 ZR	366	struct work_struct *work);
b3c97528 HH	367	extern int queue_delayed_work(struct workqueue_struct *wq,
b3c97528 HH	368	struct delayed_work *work, unsigned long delay);
7a6bc1cd	369	extern int queue_delayed_work_on(int cpu, struct workqueue_struct *wq,
28e53bdd ON	370	struct delayed_work *work, unsigned long delay);
28e53bdd ON	371
b3c97528	372	extern void flush_workqueue(struct workqueue_struct *wq);
9c5a2ba7	373	extern void drain_workqueue(struct workqueue_struct *wq);
28e53bdd	374	extern void flush_scheduled_work(void);
1da177e4	375
b3c97528	376	extern int schedule_work(struct work_struct *work);
c1a220e7	377	extern int schedule_work_on(int cpu, struct work_struct *work);
b3c97528	378	extern int schedule_delayed_work(struct delayed_work *work, unsigned long delay);
28e53bdd ON	379	extern int schedule_delayed_work_on(int cpu, struct delayed_work *work,
28e53bdd ON	380	unsigned long delay);
65f27f38	381	extern int schedule_on_each_cpu(work_func_t func);
1da177e4 LT	382	extern int keventd_up(void);
1da177e4 LT	383
65f27f38	384	int execute_in_process_context(work_func_t fn, struct execute_work *);
1da177e4	385
401a8d04	386	extern bool flush_work(struct work_struct *work);
09383498	387	extern bool flush_work_sync(struct work_struct *work);
401a8d04 TH	388	extern bool cancel_work_sync(struct work_struct *work);
	389
	390	extern bool flush_delayed_work(struct delayed_work *dwork);
09383498	391	extern bool flush_delayed_work_sync(struct delayed_work *work);
401a8d04	392	extern bool cancel_delayed_work_sync(struct delayed_work *dwork);
28e53bdd	393
dcd989cb TH	394	extern void workqueue_set_max_active(struct workqueue_struct *wq,
	395	int max_active);
	396	extern bool workqueue_congested(unsigned int cpu, struct workqueue_struct *wq);
	397	extern unsigned int work_cpu(struct work_struct *work);
	398	extern unsigned int work_busy(struct work_struct *work);
	399
1da177e4 LT	400	/*
1da177e4 LT	401	* Kill off a pending schedule_delayed_work(). Note that the work callback
071b6386 ON	402	* function may still be running on return from cancel_delayed_work(), unless
071b6386 ON	403	* it returns 1 and the work doesn't re-arm itself. Run flush_workqueue() or
28e53bdd	404	* cancel_work_sync() to wait on it.
1da177e4	405	*/
401a8d04	406	static inline bool cancel_delayed_work(struct delayed_work *work)
1da177e4	407	{
401a8d04	408	bool ret;
1da177e4	409
223a10a9	410	ret = del_timer_sync(&work->timer);
1da177e4	411	if (ret)
23b2e599	412	work_clear_pending(&work->work);
1da177e4 LT	413	return ret;
	414	}
	415
4e49627b ON	416	/*
	417	* Like above, but uses del_timer() instead of del_timer_sync(). This means,
	418	* if it returns 0 the timer function may be running and the queueing is in
	419	* progress.
	420	*/
401a8d04	421	static inline bool __cancel_delayed_work(struct delayed_work *work)
4e49627b	422	{
401a8d04	423	bool ret;
4e49627b ON	424
	425	ret = del_timer(&work->timer);
	426	if (ret)
	427	work_clear_pending(&work->work);
	428	return ret;
	429	}
	430
2d3854a3 RR	431	#ifndef CONFIG_SMP
	432	static inline long work_on_cpu(unsigned int cpu, long (fn)(void ), void *arg)
	433	{
	434	return fn(arg);
	435	}
	436	#else
	437	long work_on_cpu(unsigned int cpu, long (fn)(void ), void *arg);
	438	#endif /* CONFIG_SMP */
a25909a4	439
a0a1a5fd TH	440	#ifdef CONFIG_FREEZER
	441	extern void freeze_workqueues_begin(void);
	442	extern bool freeze_workqueues_busy(void);
	443	extern void thaw_workqueues(void);
	444	#endif /* CONFIG_FREEZER */
	445
1da177e4	446	#endif