linux/kernel/sched/swait.c

// SPDX-License-Identifier: GPL-2.0
/*
 * <linux/swait.h> (simple wait queues ) implementation:
 */

void __init_swait_queue_head(struct swait_queue_head *q, const char *name,
			     struct lock_class_key *key)
{ … }
EXPORT_SYMBOL(…);

/*
 * The thing about the wake_up_state() return value; I think we can ignore it.
 *
 * If for some reason it would return 0, that means the previously waiting
 * task is already running, so it will observe condition true (or has already).
 */
void swake_up_locked(struct swait_queue_head *q, int wake_flags)
{ … }
EXPORT_SYMBOL(…);

/*
 * Wake up all waiters. This is an interface which is solely exposed for
 * completions and not for general usage.
 *
 * It is intentionally different from swake_up_all() to allow usage from
 * hard interrupt context and interrupt disabled regions.
 */
void swake_up_all_locked(struct swait_queue_head *q)
{ … }

void swake_up_one(struct swait_queue_head *q)
{ … }
EXPORT_SYMBOL(…);

/*
 * Does not allow usage from IRQ disabled, since we must be able to
 * release IRQs to guarantee bounded hold time.
 */
void swake_up_all(struct swait_queue_head *q)
{ … }
EXPORT_SYMBOL(…);

void __prepare_to_swait(struct swait_queue_head *q, struct swait_queue *wait)
{ … }

void prepare_to_swait_exclusive(struct swait_queue_head *q, struct swait_queue *wait, int state)
{ … }
EXPORT_SYMBOL(…);

long prepare_to_swait_event(struct swait_queue_head *q, struct swait_queue *wait, int state)
{ … }
EXPORT_SYMBOL(…);

void __finish_swait(struct swait_queue_head *q, struct swait_queue *wait)
{ … }

void finish_swait(struct swait_queue_head *q, struct swait_queue *wait)
{ … }
EXPORT_SYMBOL(…);