[lttng-tools.git] / src / common / waiter.h

/*
 * Copyright (C) 2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
 * Copyright (C) 2017 Jérémie Galarneau <jeremie.galarneau@efficios.com>
 *
 * SPDX-License-Identifier: LGPL-2.1-only
 *
 * This code is originally adapted from userspace-rcu's urcu-wait.h
 */

#ifndef LTTNG_WAITER_H
#define LTTNG_WAITER_H

#define _LGPL_SOURCE

#include <stdint.h>
#include <urcu/wfstack.h>
#include <stdbool.h>
#include "macros.h"

struct lttng_waiter {
	struct cds_wfs_node wait_queue_node;
	int32_t state;
};

void lttng_waiter_init(struct lttng_waiter *waiter);

void lttng_waiter_wait(struct lttng_waiter *waiter);

/*
 * lttng_waiter_wake_up must only be called by a single waker.
 * It is invalid for multiple "wake" operations to be invoked
 * on a single waiter without re-initializing it before.
 */
void lttng_waiter_wake_up(struct lttng_waiter *waiter);

#endif /* LTTNG_WAITER_H */
Commit	Line	Data
287a512f	1	/*
ab5be9fa MJ	2	* Copyright (C) 2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
ab5be9fa MJ	3	* Copyright (C) 2017 Jérémie Galarneau <jeremie.galarneau@efficios.com>
287a512f	4	*
ab5be9fa	5	* SPDX-License-Identifier: LGPL-2.1-only
287a512f JG	6	*
	7	* This code is originally adapted from userspace-rcu's urcu-wait.h
	8	*/
	9
	10	#ifndef LTTNG_WAITER_H
	11	#define LTTNG_WAITER_H
	12
	13	#define _LGPL_SOURCE
	14
	15	#include <stdint.h>
	16	#include <urcu/wfstack.h>
	17	#include <stdbool.h>
	18	#include "macros.h"
	19
	20	struct lttng_waiter {
	21	struct cds_wfs_node wait_queue_node;
	22	int32_t state;
	23	};
	24
287a512f JG	25	void lttng_waiter_init(struct lttng_waiter *waiter);
287a512f JG	26
287a512f JG	27	void lttng_waiter_wait(struct lttng_waiter *waiter);
	28
	29	/*
	30	* lttng_waiter_wake_up must only be called by a single waker.
	31	* It is invalid for multiple "wake" operations to be invoked
	32	* on a single waiter without re-initializing it before.
	33	*/
287a512f JG	34	void lttng_waiter_wake_up(struct lttng_waiter *waiter);
	35
	36	#endif /* LTTNG_WAITER_H */