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
19 #include <urcu/wfstack.h>
22 struct cds_wfs_node wait_queue_node;
26 struct lttng_wait_queue {
27 struct cds_wfs_stack stack;
30 void lttng_waiter_init(struct lttng_waiter *waiter);
32 void lttng_waiter_wait(struct lttng_waiter *waiter);
35 * lttng_waiter_wake must only be called by a single waker.
36 * It is invalid for multiple "wake" operations to be invoked
37 * on a single waiter without re-initializing it before.
39 void lttng_waiter_wake(struct lttng_waiter *waiter);
41 void lttng_wait_queue_init(struct lttng_wait_queue *queue);
44 * Atomically add a waiter to a wait queue.
45 * A full memory barrier is issued before being added to the wait queue.
47 void lttng_wait_queue_add(struct lttng_wait_queue *queue, struct lttng_waiter *waiter);
50 * Wake every waiter present in the wait queue and remove them from
53 void lttng_wait_queue_wake_all(struct lttng_wait_queue *queue);
55 #endif /* LTTNG_WAITER_H */