[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_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,

	/* data contains off-queue information when !WORK_STRUCT_CWQ */
	WORK_OFFQ_FLAG_BASE	= WORK_STRUCT_FLAG_BITS,

	WORK_OFFQ_CANCELING	= (1 << WORK_OFFQ_FLAG_BASE),

	WORK_OFFQ_FLAG_BITS	= 1,
	WORK_OFFQ_CPU_SHIFT	= WORK_OFFQ_FLAG_BASE + WORK_OFFQ_FLAG_BITS,

	/* convenience constants */
	WORK_STRUCT_FLAG_MASK	= (1UL << WORK_STRUCT_FLAG_BITS) - 1,
	WORK_STRUCT_WQ_DATA_MASK = ~WORK_STRUCT_FLAG_MASK,
	WORK_STRUCT_NO_CPU	= (unsigned long)WORK_CPU_NONE << WORK_OFFQ_CPU_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_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(delayed_work_timer_fn,	\
				0, (unsigned long)&(n)),	\
	}

#define __DEFERRED_WORK_INITIALIZER(n, f) {			\
	.work = __WORK_INITIALIZER((n).work, (f)),		\
	.timer = TIMER_DEFERRED_INITIALIZER(delayed_work_timer_fn, \
				0, (unsigned long)&(n)),	\
	}

#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);			\
		(_work)->timer.function = delayed_work_timer_fn;\
		(_work)->timer.data = (unsigned long)(_work);	\
	} while (0)

#define INIT_DELAYED_WORK_ONSTACK(_work, _func)			\
	do {							\
		INIT_WORK_ONSTACK(&(_work)->work, (_func));	\
		init_timer_on_stack(&(_work)->timer);		\
		(_work)->timer.function = delayed_work_timer_fn;\
		(_work)->timer.data = (unsigned long)(_work);	\
	} while (0)

#define INIT_DELAYED_WORK_DEFERRABLE(_work, _func)		\
	do {							\
		INIT_WORK(&(_work)->work, (_func));		\
		init_timer_deferrable(&(_work)->timer);		\
		(_work)->timer.function = delayed_work_timer_fn;\
		(_work)->timer.data = (unsigned long)(_work);	\
	} 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.
 *
 * system_nrt_freezable_wq is equivalent to system_nrt_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 *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 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);
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 TH	29	WORK_STRUCT_DELAYED_BIT = 1, /* work item is delayed */
	30	WORK_STRUCT_CWQ_BIT = 2, /* data points to cwq */
	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,
e120153d	43	WORK_STRUCT_CWQ = 1 << WORK_STRUCT_CWQ_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 TH	59	WORK_CPU_UNBOUND = NR_CPUS,
f3421797 TH	60	WORK_CPU_NONE = NR_CPUS + 1,
bdbc5dd7 TH	61	WORK_CPU_LAST = WORK_CPU_NONE,
bdbc5dd7 TH	62
73f53c4a	63	/*
e120153d	64	* Reserve 7 bits off of cwq pointer w/ debugobjects turned
8a2e8e5d TH	65	* off. This makes cwqs aligned to 256 bytes and allows 15
8a2e8e5d TH	66	* workqueue flush colors.
73f53c4a TH	67	*/
	68	WORK_STRUCT_FLAG_BITS = WORK_STRUCT_COLOR_SHIFT +
	69	WORK_STRUCT_COLOR_BITS,
	70
b5490077 TH	71	/* data contains off-queue information when !WORK_STRUCT_CWQ */
b5490077 TH	72	WORK_OFFQ_FLAG_BASE = WORK_STRUCT_FLAG_BITS,
bbb68dfa TH	73
	74	WORK_OFFQ_CANCELING = (1 << WORK_OFFQ_FLAG_BASE),
	75
	76	WORK_OFFQ_FLAG_BITS = 1,
b5490077 TH	77	WORK_OFFQ_CPU_SHIFT = WORK_OFFQ_FLAG_BASE + WORK_OFFQ_FLAG_BITS,
	78
	79	/* convenience constants */
0f900049	80	WORK_STRUCT_FLAG_MASK = (1UL << WORK_STRUCT_FLAG_BITS) - 1,
22df02bb	81	WORK_STRUCT_WQ_DATA_MASK = ~WORK_STRUCT_FLAG_MASK,
b5490077	82	WORK_STRUCT_NO_CPU = (unsigned long)WORK_CPU_NONE << WORK_OFFQ_CPU_SHIFT,
dcd989cb TH	83
	84	/* bit mask for work_busy() return values */
	85	WORK_BUSY_PENDING = 1 << 0,
	86	WORK_BUSY_RUNNING = 1 << 1,
22df02bb TH	87	};
22df02bb TH	88
1da177e4	89	struct work_struct {
a08727ba	90	atomic_long_t data;
1da177e4	91	struct list_head entry;
6bb49e59	92	work_func_t func;
4e6045f1 JB	93	#ifdef CONFIG_LOCKDEP
	94	struct lockdep_map lockdep_map;
	95	#endif
52bad64d DH	96	};
52bad64d DH	97
7a22ad75 TH	98	#define WORK_DATA_INIT() ATOMIC_LONG_INIT(WORK_STRUCT_NO_CPU)
	99	#define WORK_DATA_STATIC_INIT() \
	100	ATOMIC_LONG_INIT(WORK_STRUCT_NO_CPU \| WORK_STRUCT_STATIC)
a08727ba	101
52bad64d DH	102	struct delayed_work {
52bad64d DH	103	struct work_struct work;
1da177e4 LT	104	struct timer_list timer;
	105	};
	106
bf6aede7 JD	107	static inline struct delayed_work to_delayed_work(struct work_struct work)
	108	{
	109	return container_of(work, struct delayed_work, work);
	110	}
	111
1fa44eca JB	112	struct execute_work {
	113	struct work_struct work;
	114	};
	115
4e6045f1 JB	116	#ifdef CONFIG_LOCKDEP
	117	/*
	118	* NB: because we have to copy the lockdep_map, setting _key
	119	* here is required, otherwise it could get initialised to the
	120	* copy of the lockdep_map!
	121	*/
	122	#define __WORK_INIT_LOCKDEP_MAP(n, k) \
	123	.lockdep_map = STATIC_LOCKDEP_MAP_INIT(n, k),
	124	#else
	125	#define __WORK_INIT_LOCKDEP_MAP(n, k)
	126	#endif
	127
65f27f38	128	#define __WORK_INITIALIZER(n, f) { \
dc186ad7	129	.data = WORK_DATA_STATIC_INIT(), \
23b2e599	130	.entry = { &(n).entry, &(n).entry }, \
65f27f38	131	.func = (f), \
4e6045f1	132	__WORK_INIT_LOCKDEP_MAP(#n, &(n)) \
65f27f38 DH	133	}
	134
	135	#define __DELAYED_WORK_INITIALIZER(n, f) { \
	136	.work = __WORK_INITIALIZER((n).work, (f)), \
d8e794df TH	137	.timer = TIMER_INITIALIZER(delayed_work_timer_fn, \
d8e794df TH	138	0, (unsigned long)&(n)), \
65f27f38 DH	139	}
65f27f38 DH	140
dd6414b5 PC	141	#define __DEFERRED_WORK_INITIALIZER(n, f) { \
dd6414b5 PC	142	.work = __WORK_INITIALIZER((n).work, (f)), \
d8e794df TH	143	.timer = TIMER_DEFERRED_INITIALIZER(delayed_work_timer_fn, \
d8e794df TH	144	0, (unsigned long)&(n)), \
dd6414b5 PC	145	}
dd6414b5 PC	146
65f27f38 DH	147	#define DECLARE_WORK(n, f) \
	148	struct work_struct n = __WORK_INITIALIZER(n, f)
	149
65f27f38 DH	150	#define DECLARE_DELAYED_WORK(n, f) \
	151	struct delayed_work n = __DELAYED_WORK_INITIALIZER(n, f)
	152
dd6414b5 PC	153	#define DECLARE_DEFERRED_WORK(n, f) \
	154	struct delayed_work n = __DEFERRED_WORK_INITIALIZER(n, f)
	155
1da177e4	156	/*
65f27f38	157	* initialize a work item's function pointer
1da177e4	158	*/
65f27f38	159	#define PREPARE_WORK(_work, _func) \
1da177e4	160	do { \
52bad64d	161	(_work)->func = (_func); \
1da177e4 LT	162	} while (0)
1da177e4 LT	163
65f27f38 DH	164	#define PREPARE_DELAYED_WORK(_work, _func) \
65f27f38 DH	165	PREPARE_WORK(&(_work)->work, (_func))
52bad64d	166
dc186ad7 TG	167	#ifdef CONFIG_DEBUG_OBJECTS_WORK
	168	extern void __init_work(struct work_struct *work, int onstack);
	169	extern void destroy_work_on_stack(struct work_struct *work);
4690c4ab TH	170	static inline unsigned int work_static(struct work_struct *work)
4690c4ab TH	171	{
22df02bb	172	return *work_data_bits(work) & WORK_STRUCT_STATIC;
4690c4ab	173	}
dc186ad7 TG	174	#else
	175	static inline void __init_work(struct work_struct *work, int onstack) { }
	176	static inline void destroy_work_on_stack(struct work_struct *work) { }
4690c4ab	177	static inline unsigned int work_static(struct work_struct *work) { return 0; }
dc186ad7 TG	178	#endif
dc186ad7 TG	179
1da177e4	180	/*
52bad64d	181	* initialize all of a work item in one go
a08727ba	182	*
b9049df5	183	* NOTE! No point in using "atomic_long_set()": using a direct
a08727ba LT	184	* assignment of the work data initializer allows the compiler
a08727ba LT	185	* to generate better code.
1da177e4	186	*/
4e6045f1	187	#ifdef CONFIG_LOCKDEP
dc186ad7	188	#define __INIT_WORK(_work, _func, _onstack) \
65f27f38	189	do { \
4e6045f1 JB	190	static struct lock_class_key __key; \
4e6045f1 JB	191	\
dc186ad7	192	__init_work((_work), _onstack); \
23b2e599	193	(_work)->data = (atomic_long_t) WORK_DATA_INIT(); \
4e6045f1	194	lockdep_init_map(&(_work)->lockdep_map, #_work, &__key, 0);\
65f27f38 DH	195	INIT_LIST_HEAD(&(_work)->entry); \
	196	PREPARE_WORK((_work), (_func)); \
	197	} while (0)
4e6045f1	198	#else
dc186ad7	199	#define __INIT_WORK(_work, _func, _onstack) \
4e6045f1	200	do { \
dc186ad7	201	__init_work((_work), _onstack); \
4e6045f1 JB	202	(_work)->data = (atomic_long_t) WORK_DATA_INIT(); \
	203	INIT_LIST_HEAD(&(_work)->entry); \
	204	PREPARE_WORK((_work), (_func)); \
	205	} while (0)
	206	#endif
65f27f38	207
dc186ad7 TG	208	#define INIT_WORK(_work, _func) \
	209	do { \
	210	__INIT_WORK((_work), (_func), 0); \
	211	} while (0)
	212
ca1cab37	213	#define INIT_WORK_ONSTACK(_work, _func) \
dc186ad7 TG	214	do { \
	215	__INIT_WORK((_work), (_func), 1); \
	216	} while (0)
	217
65f27f38 DH	218	#define INIT_DELAYED_WORK(_work, _func) \
	219	do { \
	220	INIT_WORK(&(_work)->work, (_func)); \
	221	init_timer(&(_work)->timer); \
d8e794df TH	222	(_work)->timer.function = delayed_work_timer_fn;\
d8e794df TH	223	(_work)->timer.data = (unsigned long)(_work); \
52bad64d DH	224	} while (0)
52bad64d DH	225
ca1cab37	226	#define INIT_DELAYED_WORK_ONSTACK(_work, _func) \
6d612b0f	227	do { \
ca1cab37	228	INIT_WORK_ONSTACK(&(_work)->work, (_func)); \
6d612b0f	229	init_timer_on_stack(&(_work)->timer); \
d8e794df TH	230	(_work)->timer.function = delayed_work_timer_fn;\
d8e794df TH	231	(_work)->timer.data = (unsigned long)(_work); \
6d612b0f PZ	232	} while (0)
6d612b0f PZ	233
dc186ad7	234	#define INIT_DELAYED_WORK_DEFERRABLE(_work, _func) \
28287033 VP	235	do { \
	236	INIT_WORK(&(_work)->work, (_func)); \
	237	init_timer_deferrable(&(_work)->timer); \
d8e794df TH	238	(_work)->timer.function = delayed_work_timer_fn;\
d8e794df TH	239	(_work)->timer.data = (unsigned long)(_work); \
28287033 VP	240	} while (0)
28287033 VP	241
365970a1 DH	242	/**
	243	* work_pending - Find out whether a work item is currently pending
	244	* @work: The work item in question
	245	*/
	246	#define work_pending(work) \
22df02bb	247	test_bit(WORK_STRUCT_PENDING_BIT, work_data_bits(work))
365970a1 DH	248
	249	/**
	250	* delayed_work_pending - Find out whether a delayable work item is currently
	251	* pending
	252	* @work: The work item in question
	253	*/
0221872a LT	254	#define delayed_work_pending(w) \
0221872a LT	255	work_pending(&(w)->work)
365970a1	256
65f27f38	257	/**
23b2e599 ON	258	* work_clear_pending - for internal use only, mark a work item as not pending
23b2e599 ON	259	* @work: The work item in question
65f27f38	260	*/
23b2e599	261	#define work_clear_pending(work) \
22df02bb	262	clear_bit(WORK_STRUCT_PENDING_BIT, work_data_bits(work))
65f27f38	263
c54fce6e TH	264	/*
	265	* Workqueue flags and constants. For details, please refer to
	266	* Documentation/workqueue.txt.
	267	*/
97e37d7b	268	enum {
bdbc5dd7	269	WQ_NON_REENTRANT = 1 << 0, /* guarantee non-reentrance */
c7fc77f7	270	WQ_UNBOUND = 1 << 1, /* not bound to any cpu */
58a69cb4	271	WQ_FREEZABLE = 1 << 2, /* freeze during suspend */
6370a6ad	272	WQ_MEM_RECLAIM = 1 << 3, /* may be used for memory reclaim */
649027d7	273	WQ_HIGHPRI = 1 << 4, /* high priority */
fb0e7beb	274	WQ_CPU_INTENSIVE = 1 << 5, /* cpu instensive workqueue */
b71ab8c2	275
9c5a2ba7	276	WQ_DRAINING = 1 << 6, /* internal: workqueue is draining */
6370a6ad	277	WQ_RESCUER = 1 << 7, /* internal: workqueue has rescuer */
e41e704b	278
b71ab8c2	279	WQ_MAX_ACTIVE = 512, /* I like 512, better ideas? */
f3421797	280	WQ_MAX_UNBOUND_PER_CPU = 4, /* 4 * #cpus for unbound wq */
b71ab8c2	281	WQ_DFL_ACTIVE = WQ_MAX_ACTIVE / 2,
97e37d7b	282	};
52bad64d	283
f3421797 TH	284	/* unbound wq's aren't per-cpu, scale max_active according to #cpus */
	285	#define WQ_UNBOUND_MAX_ACTIVE \
	286	max_t(int, WQ_MAX_ACTIVE, num_possible_cpus() * WQ_MAX_UNBOUND_PER_CPU)
65f27f38	287
d320c038 TH	288	/*
	289	* System-wide workqueues which are always present.
	290	*
	291	* system_wq is the one used by schedule[_delayed]_work[_on]().
	292	* Multi-CPU multi-threaded. There are users which expect relatively
	293	* short queue flush time. Don't queue works which can run for too
	294	* long.
	295	*
	296	* system_long_wq is similar to system_wq but may host long running
	297	* works. Queue flushing might take relatively long.
	298	*
	299	* system_nrt_wq is non-reentrant and guarantees that any given work
	300	* item is never executed in parallel by multiple CPUs. Queue
	301	* flushing might take relatively long.
f3421797 TH	302	*
	303	* system_unbound_wq is unbound workqueue. Workers are not bound to
	304	* any specific CPU, not concurrency managed, and all queued works are
	305	* executed immediately as long as max_active limit is not reached and
	306	* resources are available.
4149efb2	307	*
24d51add TH	308	* system_freezable_wq is equivalent to system_wq except that it's
24d51add TH	309	* freezable.
62d3c543 AS	310	*
	311	* system_nrt_freezable_wq is equivalent to system_nrt_wq except that
	312	* it's freezable.
d320c038 TH	313	*/
	314	extern struct workqueue_struct *system_wq;
	315	extern struct workqueue_struct *system_long_wq;
	316	extern struct workqueue_struct *system_nrt_wq;
f3421797	317	extern struct workqueue_struct *system_unbound_wq;
24d51add	318	extern struct workqueue_struct *system_freezable_wq;
62d3c543	319	extern struct workqueue_struct *system_nrt_freezable_wq;
52bad64d	320
4e6045f1	321	extern struct workqueue_struct *
b196be89 TH	322	__alloc_workqueue_key(const char *fmt, unsigned int flags, int max_active,
b196be89 TH	323	struct lock_class_key key, const char lock_name, ...) __printf(1, 6);
4e6045f1	324
b196be89 TH	325	/**
	326	* alloc_workqueue - allocate a workqueue
	327	* @fmt: printf format for the name of the workqueue
	328	* @flags: WQ_* flags
	329	* @max_active: max in-flight work items, 0 for default
	330	* @args: args for @fmt
	331	*
	332	* Allocate a workqueue with the specified parameters. For detailed
	333	* information on WQ_* flags, please refer to Documentation/workqueue.txt.
	334	*
	335	* The __lock_name macro dance is to guarantee that single lock_class_key
	336	* doesn't end up with different namesm, which isn't allowed by lockdep.
	337	*
	338	* RETURNS:
	339	* Pointer to the allocated workqueue on success, %NULL on failure.
	340	*/
4e6045f1	341	#ifdef CONFIG_LOCKDEP
b196be89	342	#define alloc_workqueue(fmt, flags, max_active, args...) \
4e6045f1 JB	343	({ \
4e6045f1 JB	344	static struct lock_class_key __key; \
eb13ba87 JB	345	const char *__lock_name; \
eb13ba87 JB	346	\
b196be89 TH	347	if (__builtin_constant_p(fmt)) \
b196be89 TH	348	__lock_name = (fmt); \
eb13ba87	349	else \
b196be89	350	__lock_name = #fmt; \
4e6045f1	351	\
b196be89 TH	352	__alloc_workqueue_key((fmt), (flags), (max_active), \
b196be89 TH	353	&__key, __lock_name, ##args); \
4e6045f1 JB	354	})
4e6045f1 JB	355	#else
b196be89 TH	356	#define alloc_workqueue(fmt, flags, max_active, args...) \
	357	__alloc_workqueue_key((fmt), (flags), (max_active), \
	358	NULL, NULL, ##args)
4e6045f1 JB	359	#endif
4e6045f1 JB	360
81dcaf65 TH	361	/**
81dcaf65 TH	362	* alloc_ordered_workqueue - allocate an ordered workqueue
b196be89	363	* @fmt: printf format for the name of the workqueue
58a69cb4	364	* @flags: WQ_* flags (only WQ_FREEZABLE and WQ_MEM_RECLAIM are meaningful)
b196be89	365	* @args: args for @fmt
81dcaf65 TH	366	*
	367	* Allocate an ordered workqueue. An ordered workqueue executes at
	368	* most one work item at any given time in the queued order. They are
	369	* implemented as unbound workqueues with @max_active of one.
	370	*
	371	* RETURNS:
	372	* Pointer to the allocated workqueue on success, %NULL on failure.
	373	*/
b196be89 TH	374	#define alloc_ordered_workqueue(fmt, flags, args...) \
b196be89 TH	375	alloc_workqueue(fmt, WQ_UNBOUND \| (flags), 1, ##args)
81dcaf65	376
97e37d7b	377	#define create_workqueue(name) \
6370a6ad	378	alloc_workqueue((name), WQ_MEM_RECLAIM, 1)
58a69cb4 TH	379	#define create_freezable_workqueue(name) \
58a69cb4 TH	380	alloc_workqueue((name), WQ_FREEZABLE \| WQ_UNBOUND \| WQ_MEM_RECLAIM, 1)
97e37d7b	381	#define create_singlethread_workqueue(name) \
6370a6ad	382	alloc_workqueue((name), WQ_UNBOUND \| WQ_MEM_RECLAIM, 1)
1da177e4 LT	383
	384	extern void destroy_workqueue(struct workqueue_struct *wq);
	385
d4283e93	386	extern bool queue_work_on(int cpu, struct workqueue_struct *wq,
c1a220e7	387	struct work_struct *work);
d4283e93 TH	388	extern bool queue_work(struct workqueue_struct wq, struct work_struct work);
d4283e93 TH	389	extern bool queue_delayed_work_on(int cpu, struct workqueue_struct *wq,
28e53bdd	390	struct delayed_work *work, unsigned long delay);
d4283e93	391	extern bool queue_delayed_work(struct workqueue_struct *wq,
0a13c00e	392	struct delayed_work *work, unsigned long delay);
8376fe22 TH	393	extern bool mod_delayed_work_on(int cpu, struct workqueue_struct *wq,
	394	struct delayed_work *dwork, unsigned long delay);
	395	extern bool mod_delayed_work(struct workqueue_struct *wq,
	396	struct delayed_work *dwork, unsigned long delay);
28e53bdd	397
b3c97528	398	extern void flush_workqueue(struct workqueue_struct *wq);
9c5a2ba7	399	extern void drain_workqueue(struct workqueue_struct *wq);
28e53bdd	400	extern void flush_scheduled_work(void);
1da177e4	401
d4283e93 TH	402	extern bool schedule_work_on(int cpu, struct work_struct *work);
	403	extern bool schedule_work(struct work_struct *work);
	404	extern bool schedule_delayed_work_on(int cpu, struct delayed_work *work,
	405	unsigned long delay);
	406	extern bool schedule_delayed_work(struct delayed_work *work,
	407	unsigned long delay);
65f27f38	408	extern int schedule_on_each_cpu(work_func_t func);
1da177e4 LT	409	extern int keventd_up(void);
1da177e4 LT	410
65f27f38	411	int execute_in_process_context(work_func_t fn, struct execute_work *);
1da177e4	412
401a8d04	413	extern bool flush_work(struct work_struct *work);
09383498	414	extern bool flush_work_sync(struct work_struct *work);
401a8d04 TH	415	extern bool cancel_work_sync(struct work_struct *work);
	416
	417	extern bool flush_delayed_work(struct delayed_work *dwork);
09383498	418	extern bool flush_delayed_work_sync(struct delayed_work *work);
401a8d04	419	extern bool cancel_delayed_work_sync(struct delayed_work *dwork);
28e53bdd	420
dcd989cb TH	421	extern void workqueue_set_max_active(struct workqueue_struct *wq,
	422	int max_active);
	423	extern bool workqueue_congested(unsigned int cpu, struct workqueue_struct *wq);
	424	extern unsigned int work_cpu(struct work_struct *work);
	425	extern unsigned int work_busy(struct work_struct *work);
	426
1da177e4 LT	427	/*
1da177e4 LT	428	* Kill off a pending schedule_delayed_work(). Note that the work callback
071b6386 ON	429	* function may still be running on return from cancel_delayed_work(), unless
071b6386 ON	430	* it returns 1 and the work doesn't re-arm itself. Run flush_workqueue() or
28e53bdd	431	* cancel_work_sync() to wait on it.
1da177e4	432	*/
401a8d04	433	static inline bool cancel_delayed_work(struct delayed_work *work)
1da177e4	434	{
401a8d04	435	bool ret;
1da177e4	436
223a10a9	437	ret = del_timer_sync(&work->timer);
1da177e4	438	if (ret)
23b2e599	439	work_clear_pending(&work->work);
1da177e4 LT	440	return ret;
	441	}
	442
4e49627b ON	443	/*
	444	* Like above, but uses del_timer() instead of del_timer_sync(). This means,
	445	* if it returns 0 the timer function may be running and the queueing is in
	446	* progress.
	447	*/
401a8d04	448	static inline bool __cancel_delayed_work(struct delayed_work *work)
4e49627b	449	{
401a8d04	450	bool ret;
4e49627b ON	451
	452	ret = del_timer(&work->timer);
	453	if (ret)
	454	work_clear_pending(&work->work);
	455	return ret;
	456	}
	457
2d3854a3 RR	458	#ifndef CONFIG_SMP
	459	static inline long work_on_cpu(unsigned int cpu, long (fn)(void ), void *arg)
	460	{
	461	return fn(arg);
	462	}
	463	#else
	464	long work_on_cpu(unsigned int cpu, long (fn)(void ), void *arg);
	465	#endif /* CONFIG_SMP */
a25909a4	466
a0a1a5fd TH	467	#ifdef CONFIG_FREEZER
	468	extern void freeze_workqueues_begin(void);
	469	extern bool freeze_workqueues_busy(void);
	470	extern void thaw_workqueues(void);
	471	#endif /* CONFIG_FREEZER */
	472
1da177e4	473	#endif