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

/*
 * 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 "macros.hpp"

#include <stdbool.h>
#include <stdint.h>
#include <urcu/wfstack.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
	1	/*
	2	* Copyright (C) 2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
	3	* Copyright (C) 2017 Jérémie Galarneau <jeremie.galarneau@efficios.com>
	4	*
	5	* SPDX-License-Identifier: LGPL-2.1-only
	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 "macros.hpp"
	16
	17	#include <stdbool.h>
	18	#include <stdint.h>
	19	#include <urcu/wfstack.h>
	20
	21	struct lttng_waiter {
	22	struct cds_wfs_node wait_queue_node;
	23	int32_t state;
	24	};
	25
	26	void lttng_waiter_init(struct lttng_waiter *waiter);
	27
	28	void lttng_waiter_wait(struct lttng_waiter *waiter);
	29
	30	/*
	31	* lttng_waiter_wake_up must only be called by a single waker.
	32	* It is invalid for multiple "wake" operations to be invoked
	33	* on a single waiter without re-initializing it before.
	34	*/
	35	void lttng_waiter_wake_up(struct lttng_waiter *waiter);
	36
	37	#endif /* LTTNG_WAITER_H */