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>
30 waker(const waker&) = default;
31 waker(waker&&) = default;
32 waker& operator=(const waker& other)
34 _state = other._state;
37 waker& operator=(waker&& other)
39 _state = other._state;
48 waker(int32_t& state) : _state{ state }
61 /* Deactivate copy and assignment. */
62 waiter(const waiter&) = delete;
63 waiter(waiter&&) = delete;
64 waiter& operator=(const waiter&) = delete;
65 waiter& operator=(waiter&&) = delete;
74 cds_wfs_node _wait_queue_node;
78 class wait_queue final {
82 /* Deactivate copy and assignment. */
83 wait_queue(const wait_queue&) = delete;
84 wait_queue(wait_queue&&) = delete;
85 wait_queue& operator=(const wait_queue&) = delete;
86 wait_queue& operator=(wait_queue&&) = delete;
87 ~wait_queue() = default;
90 * Atomically add a waiter to a wait queue.
91 * A full memory barrier is issued before being added to the wait queue.
93 void add(waiter& waiter) noexcept;
95 * Wake every waiter present in the wait queue and remove them from
101 cds_wfs_stack _stack;
103 } /* namespace synchro */
104 } /* namespace lttng */
106 #endif /* LTTNG_WAITER_H */