2 * Copyright (C) 2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
3 * Copyright (C) 2017 Jérémie Galarneau <jeremie.galarneau@efficios.com>
5 * SPDX-License-Identifier: LGPL-2.1-only
7 * This code is originally adapted from userspace-rcu's urcu-wait.h
10 #ifndef LTTNG_WAITER_H
11 #define LTTNG_WAITER_H
16 #include <urcu/wfstack.h>
21 struct cds_wfs_node wait_queue_node
;
25 struct lttng_wait_queue
{
26 struct cds_wfs_stack stack
;
30 void lttng_waiter_init(struct lttng_waiter
*waiter
);
33 void lttng_waiter_wait(struct lttng_waiter
*waiter
);
36 * lttng_waiter_wake must only be called by a single waker.
37 * It is invalid for multiple "wake" operations to be invoked
38 * on a single waiter without re-initializing it before.
41 void lttng_waiter_wake(struct lttng_waiter
*waiter
);
44 void lttng_wait_queue_init(struct lttng_wait_queue
*queue
);
47 * Atomically add a waiter to a wait queue.
48 * A full memory barrier is issued before being added to the wait queue.
51 void lttng_wait_queue_add(struct lttng_wait_queue
*queue
,
52 struct lttng_waiter
*waiter
);
55 * Wake every waiter present in the wait queue and remove them from
59 void lttng_wait_queue_wake_all(struct lttng_wait_queue
*queue
);
61 #endif /* LTTNG_WAITER_H */