3  * workqueue.h --- work queue handling for Linux.
20  * The first word is the work queue pointer and the flags rolled into
23 #define work_data_bits(work) ((unsigned long *)(&(work)->data))  argument
26 	WORK_STRUCT_PENDING_BIT	= 0,	/* work item is pending execution */
27 	WORK_STRUCT_INACTIVE_BIT,	/* work item is inactive */
29 	WORK_STRUCT_LINKED_BIT,		/* next work is linked to this one */
66 	 * When a work item is off queue, the high bits encode off-queue flags
114 	struct work_struct work;  member
117 	/* target workqueue and CPU ->timer uses to queue ->work */
123 	struct work_struct work;  member
126 	/* target workqueue ->rcu uses to queue ->work */
155 	 * Work items in this workqueue are affine to these CPUs and not allowed
196 	 * CPU pods are used to improve execution locality of unbound work
206 	 * @ordered: work items must be executed one by one in queueing order
211 static inline struct delayed_work *to_delayed_work(struct work_struct *work)  in to_delayed_work()  argument
213 	return container_of(work, struct delayed_work, work);  in to_delayed_work()
216 static inline struct rcu_work *to_rcu_work(struct work_struct *work)  in to_rcu_work()  argument
218 	return container_of(work, struct rcu_work, work);  in to_rcu_work()
222 	struct work_struct work;  member
245 	.work = __WORK_INITIALIZER((n).work, (f)),			\
260 extern void __init_work(struct work_struct *work, int onstack);
261 extern void destroy_work_on_stack(struct work_struct *work);
262 extern void destroy_delayed_work_on_stack(struct delayed_work *work);
263 static inline unsigned int work_static(struct work_struct *work)  in work_static()  argument
265 	return *work_data_bits(work) & WORK_STRUCT_STATIC;  in work_static()
268 static inline void __init_work(struct work_struct *work, int onstack) { }  in __init_work()  argument
269 static inline void destroy_work_on_stack(struct work_struct *work) { }  in destroy_work_on_stack()  argument
270 static inline void destroy_delayed_work_on_stack(struct delayed_work *work) { }  in destroy_delayed_work_on_stack()  argument
271 static inline unsigned int work_static(struct work_struct *work) { return 0; }  in work_static()  argument
275  * initialize all of a work item in one go
278  * assignment of the work data initializer allows the compiler
318 		INIT_WORK(&(_work)->work, (_func));			\
326 		INIT_WORK_ONSTACK(&(_work)->work, (_func));		\
345 	INIT_WORK(&(_work)->work, (_func))
348 	INIT_WORK_ONSTACK(&(_work)->work, (_func))
351  * work_pending - Find out whether a work item is currently pending
352  * @work: The work item in question
354 #define work_pending(work) \  argument
355 	test_bit(WORK_STRUCT_PENDING_BIT, work_data_bits(work))
358  * delayed_work_pending - Find out whether a delayable work item is currently
360  * @w: The work item in question
363 	work_pending(&(w)->work)
387 	 * however, for example, a per-cpu work item scheduled from an
389 	 * execute the work item on that CPU breaking the idleness, which in
435  * system_highpri_wq is similar to system_wq but for work items which
455  * system_bh[_highpri]_wq are convenience interface to softirq. BH work items
475  * @max_active: max in-flight work items, 0 for default
478  * For a per-cpu workqueue, @max_active limits the number of in-flight work
480  * executing at most one work item for the workqueue.
482  * For unbound workqueues, @max_active limits the number of in-flight work items
484  * at most 16 work items executing for the workqueue in the whole system.
494  * of interdependent work items for the workqueue.
515  * @max_active: max in-flight work items, 0 for default
558  * most one work item at any given time in the queued order.  They are
587 			struct work_struct *work);
589 			    struct work_struct *work);
591 			struct delayed_work *work, unsigned long delay);
603 extern bool flush_work(struct work_struct *work);
604 extern bool cancel_work(struct work_struct *work);
605 extern bool cancel_work_sync(struct work_struct *work);
611 extern bool disable_work(struct work_struct *work);
612 extern bool disable_work_sync(struct work_struct *work);
613 extern bool enable_work(struct work_struct *work);
628 extern unsigned int work_busy(struct work_struct *work);
637  * queue_work - queue work on a workqueue
639  * @work: work to queue
641  * Returns %false if @work was already on a queue, %true otherwise.
643  * We queue the work to the CPU on which it was submitted, but if the CPU dies
648  * the CPU which will execute @work by the time such work executes, e.g.,
654  *   WRITE_ONCE(x, 1);			[ @work is being executed ]
655  *   r0 = queue_work(wq, work);		  r1 = READ_ONCE(x);
660 			      struct work_struct *work)  in queue_work()  argument
662 	return queue_work_on(WORK_CPU_UNBOUND, wq, work);  in queue_work()
666  * queue_delayed_work - queue work on a workqueue after delay
668  * @dwork: delayable work to queue
681  * mod_delayed_work - modify delay of or queue a delayed work
683  * @dwork: work to queue
696  * schedule_work_on - put work task on a specific cpu
697  * @cpu: cpu to put the work task on
698  * @work: job to be done
702 static inline bool schedule_work_on(int cpu, struct work_struct *work)  in schedule_work_on()  argument
704 	return queue_work_on(cpu, system_wq, work);  in schedule_work_on()
708  * schedule_work - put work task in global workqueue
709  * @work: job to be done
711  * Returns %false if @work was already on the kernel-global workqueue and
721 static inline bool schedule_work(struct work_struct *work)  in schedule_work()  argument
723 	return queue_work(system_wq, work);  in schedule_work()
727  * enable_and_queue_work - Enable and queue a work item on a specific workqueue
729  * @work: The work item to be enabled and queued
732  * providing a convenient way to enable and queue a work item in a single call.
733  * It invokes enable_work() on @work and then queues it if the disable depth
734  * reached 0. Returns %true if the disable depth reached 0 and @work is queued,
737  * Note that @work is always queued when disable depth reaches zero. If the
738  * desired behavior is queueing only if certain events took place while @work is
743 					 struct work_struct *work)  in enable_and_queue_work()  argument
745 	if (enable_work(work)) {  in enable_and_queue_work()
746 		queue_work(wq, work);  in enable_and_queue_work()
792  * schedule_delayed_work_on - queue work in global workqueue on CPU after delay
807  * schedule_delayed_work - put work task in global workqueue after delay
833  * A new key is defined for each caller to make sure the work
847  * A new key is defined for each caller to make sure the work