1 // SPDX-License-Identifier: GPL-2.0
3  * <linux/swait.h> (simple wait queues ) implementation:
9 	raw_spin_lock_init(&q->lock);  in __init_swait_queue_head()
10 	lockdep_set_class_and_name(&q->lock, key, name);  in __init_swait_queue_head()
11 	INIT_LIST_HEAD(&q->task_list);  in __init_swait_queue_head()
25 	if (list_empty(&q->task_list))  in swake_up_locked()
28 	curr = list_first_entry(&q->task_list, typeof(*curr), task_list);  in swake_up_locked()
29 	wake_up_process(curr->task);  in swake_up_locked()
30 	list_del_init(&curr->task_list);  in swake_up_locked()
43 	while (!list_empty(&q->task_list))  in swake_up_all_locked()
51 	raw_spin_lock_irqsave(&q->lock, flags);  in swake_up_one()
53 	raw_spin_unlock_irqrestore(&q->lock, flags);  in swake_up_one()
66 	raw_spin_lock_irq(&q->lock);  in swake_up_all()
67 	list_splice_init(&q->task_list, &tmp);  in swake_up_all()
71 		wake_up_state(curr->task, TASK_NORMAL);  in swake_up_all()
72 		list_del_init(&curr->task_list);  in swake_up_all()
77 		raw_spin_unlock_irq(&q->lock);  in swake_up_all()
78 		raw_spin_lock_irq(&q->lock);  in swake_up_all()
80 	raw_spin_unlock_irq(&q->lock);  in swake_up_all()
84 void __prepare_to_swait(struct swait_queue_head *q, struct swait_queue *wait)  in __prepare_to_swait()  argument
86 	wait->task = current;  in __prepare_to_swait()
87 	if (list_empty(&wait->task_list))  in __prepare_to_swait()
88 		list_add_tail(&wait->task_list, &q->task_list);  in __prepare_to_swait()
91 void prepare_to_swait_exclusive(struct swait_queue_head *q, struct swait_queue *wait, int state)  in prepare_to_swait_exclusive()  argument
95 	raw_spin_lock_irqsave(&q->lock, flags);  in prepare_to_swait_exclusive()
96 	__prepare_to_swait(q, wait);  in prepare_to_swait_exclusive()
97 	set_current_state(state);  in prepare_to_swait_exclusive()
98 	raw_spin_unlock_irqrestore(&q->lock, flags);  in prepare_to_swait_exclusive()
102 long prepare_to_swait_event(struct swait_queue_head *q, struct swait_queue *wait, int state)  in prepare_to_swait_event()  argument
107 	raw_spin_lock_irqsave(&q->lock, flags);  in prepare_to_swait_event()
108 	if (signal_pending_state(state, current)) {  in prepare_to_swait_event()
113 		list_del_init(&wait->task_list);  in prepare_to_swait_event()
114 		ret = -ERESTARTSYS;  in prepare_to_swait_event()
116 		__prepare_to_swait(q, wait);  in prepare_to_swait_event()
117 		set_current_state(state);  in prepare_to_swait_event()
119 	raw_spin_unlock_irqrestore(&q->lock, flags);  in prepare_to_swait_event()
125 void __finish_swait(struct swait_queue_head *q, struct swait_queue *wait)  in __finish_swait()  argument
128 	if (!list_empty(&wait->task_list))  in __finish_swait()
129 		list_del_init(&wait->task_list);  in __finish_swait()
132 void finish_swait(struct swait_queue_head *q, struct swait_queue *wait)  in finish_swait()  argument
138 	if (!list_empty_careful(&wait->task_list)) {  in finish_swait()
139 		raw_spin_lock_irqsave(&q->lock, flags);  in finish_swait()
140 		list_del_init(&wait->task_list);  in finish_swait()
141 		raw_spin_unlock_irqrestore(&q->lock, flags);  in finish_swait()