1#ifndef BOOST_SMART_PTR_DETAIL_YIELD_K_HPP_INCLUDED
2#define BOOST_SMART_PTR_DETAIL_YIELD_K_HPP_INCLUDED
3
4// MS compatible compilers support #pragma once
5
6#if defined(_MSC_VER) && (_MSC_VER >= 1020)
7# pragma once
8#endif
9
10// boost/smart_ptr/detail/yield_k.hpp
11//
12// Copyright 2008, 2020 Peter Dimov
13//
14// inline void boost::detail::yield( unsigned k );
15//
16// Typical use:
17// for( unsigned k = 0; !try_lock(); ++k ) yield( k );
18//
19// Distributed under the Boost Software License, Version 1.0.
20// https://www.boost.org/LICENSE_1_0.txt
21
22#include <boost/smart_ptr/detail/sp_thread_pause.hpp>
23#include <boost/smart_ptr/detail/sp_thread_sleep.hpp>
24#include <boost/config.hpp>
25
26namespace boost
27{
28
29namespace detail
30{
31
32inline void yield( unsigned k )
33{
34 // Experiments on Windows and Fedora 32 show that a single pause,
35 // followed by an immediate sp_thread_sleep(), is best.
36
37 if( k == 0 )
38 {
39 sp_thread_pause();
40 }
41 else
42 {
43 sp_thread_sleep();
44 }
45}
46
47} // namespace detail
48
49} // namespace boost
50
51#endif // #ifndef BOOST_SMART_PTR_DETAIL_YIELD_K_HPP_INCLUDED
52

source code of include/boost/smart_ptr/detail/yield_k.hpp