9  * task_work_add - ask the @task to execute @work->func()
10  * @task: the task which should run the callback
12  * @notify: how to notify the targeted task
14  * Queue @work for task_work_run() below and notify the @task if @notify
16  * it will interrupt the targeted task and run the task_work. @TWA_RESUME
17  * work is run only when the task exits the kernel and returns to user mode,
18  * or before entering guest mode. Fails if the @task is exiting/exited and thus
20  * @task goes through one of the aforementioned transitions, or exits.
22  * If the targeted task is exiting, then an error is returned and the work item
32 int task_work_add(struct task_struct *task, struct callback_head *work,  in task_work_add()  argument
39 		head = READ_ONCE(task->task_works);  in task_work_add()
43 	} while (cmpxchg(&task->task_works, head, work) != head);  in task_work_add()
49 		set_notify_resume(task);  in task_work_add()
57 		if (!(READ_ONCE(task->jobctl) & JOBCTL_TASK_WORK) &&  in task_work_add()
58 		    lock_task_sighand(task, &flags)) {  in task_work_add()
59 			task->jobctl |= JOBCTL_TASK_WORK;  in task_work_add()
60 			signal_wake_up(task, 0);  in task_work_add()
61 			unlock_task_sighand(task, &flags);  in task_work_add()
74  * @task: the task which should execute the work
84 task_work_cancel(struct task_struct *task, task_work_func_t func)  in task_work_cancel()  argument
86 	struct callback_head **pprev = &task->task_works;  in task_work_cancel()
90 	if (likely(!task->task_works))  in task_work_cancel()
98 	raw_spin_lock_irqsave(&task->pi_lock, flags);  in task_work_cancel()
105 	raw_spin_unlock_irqrestore(&task->pi_lock, flags);  in task_work_cancel()
114  * Called before the task returns to the user-mode or stops, or when
120 	struct task_struct *task = current;  in task_work_run()  local
130 			work = READ_ONCE(task->task_works);  in task_work_run()
132 				if (task->flags & PF_EXITING)  in task_work_run()
137 		} while (cmpxchg(&task->task_works, work, head) != work);  in task_work_run()
146 		raw_spin_lock_irq(&task->pi_lock);  in task_work_run()
147 		raw_spin_unlock_irq(&task->pi_lock);  in task_work_run()