19  * task_work_add - ask the @task to execute @work->func()
20  * @task: the task which should run the callback
22  * @notify: how to notify the targeted task
24  * Queue @work for task_work_run() below and notify the @task if @notify
28  * task and run the task_work, regardless of whether the task is currently
31  * reschedule IPI to force the targeted task to reschedule and run task_work.
33  * task_work be run as soon as possible, just whenever the task enters the
35  * @TWA_RESUME work is run only when the task exits the kernel and returns to
38  * current @task and if the current context is NMI.
40  * Fails if the @task is exiting/exited and thus it can't process this @work.
41  * Otherwise @work->func() will be called when the @task goes through one of
44  * If the targeted task is exiting, then an error is returned and the work item
54 int task_work_add(struct task_struct *task, struct callback_head *work,  in task_work_add()  argument
60 		if (WARN_ON_ONCE(task != current))  in task_work_add()
68 	head = READ_ONCE(task->task_works);  in task_work_add()
73 	} while (!try_cmpxchg(&task->task_works, &head, work));  in task_work_add()
79 		set_notify_resume(task);  in task_work_add()
82 		set_notify_signal(task);  in task_work_add()
85 		__set_notify_signal(task);  in task_work_add()
102  * @task: the task which should execute the work
110 task_work_cancel_match(struct task_struct *task,  in task_work_cancel_match()  argument
114 	struct callback_head **pprev = &task->task_works;  in task_work_cancel_match()
118 	if (likely(!task_work_pending(task)))  in task_work_cancel_match()
126 	raw_spin_lock_irqsave(&task->pi_lock, flags);  in task_work_cancel_match()
135 	raw_spin_unlock_irqrestore(&task->pi_lock, flags);  in task_work_cancel_match()
147  * @task: the task which should execute the func's work
157 task_work_cancel_func(struct task_struct *task, task_work_func_t func)  in task_work_cancel_func()  argument
159 	return task_work_cancel_match(task, task_work_func_match, func);  in task_work_cancel_func()
169  * @task: the task which should execute the work
172  * Remove a callback from a task's queue if queued.
177 bool task_work_cancel(struct task_struct *task, struct callback_head *cb)  in task_work_cancel()  argument
181 	ret = task_work_cancel_match(task, task_work_match, cb);  in task_work_cancel()
190  * Called before the task returns to the user-mode or stops, or when
196 	struct task_struct *task = current;  in task_work_run()  local
204 		work = READ_ONCE(task->task_works);  in task_work_run()
208 				if (task->flags & PF_EXITING)  in task_work_run()
213 		} while (!try_cmpxchg(&task->task_works, &work, head));  in task_work_run()
222 		raw_spin_lock_irq(&task->pi_lock);  in task_work_run()
223 		raw_spin_unlock_irq(&task->pi_lock);  in task_work_run()