linux/include/linux/rcuwait.h

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _LINUX_RCUWAIT_H_
#define _LINUX_RCUWAIT_H_

#include <linux/rcupdate.h>
#include <linux/sched/signal.h>

/*
 * rcuwait provides a way of blocking and waking up a single
 * task in an rcu-safe manner.
 *
 * The only time @task is non-nil is when a user is blocked (or
 * checking if it needs to) on a condition, and reset as soon as we
 * know that the condition has succeeded and are awoken.
 */
struct rcuwait { … };

#define __RCUWAIT_INITIALIZER(name) …

static inline void rcuwait_init(struct rcuwait *w)
{ … }

/*
 * Note: this provides no serialization and, just as with waitqueues,
 * requires care to estimate as to whether or not the wait is active.
 */
static inline int rcuwait_active(struct rcuwait *w)
{ … }

extern int rcuwait_wake_up(struct rcuwait *w);

/*
 * The caller is responsible for locking around rcuwait_wait_event(),
 * and [prepare_to/finish]_rcuwait() such that writes to @task are
 * properly serialized.
 */

static inline void prepare_to_rcuwait(struct rcuwait *w)
{ … }

extern void finish_rcuwait(struct rcuwait *w);

#define ___rcuwait_wait_event(w, condition, state, ret, cmd) …

#define rcuwait_wait_event(w, condition, state) …

#define __rcuwait_wait_event_timeout(w, condition, state, timeout) …

#define rcuwait_wait_event_timeout(w, condition, state, timeout) …

#endif /* _LINUX_RCUWAIT_H_ */