<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "https://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/xhtml;charset=UTF-8"/>
<meta http-equiv="X-UA-Compatible" content="IE=9"/>
<meta name="generator" content="Doxygen 1.8.15"/>
<meta name="viewport" content="width=device-width, initial-scale=1"/>
<title>libstdc++: atomic_futex.h Source File</title>
<link href="tabs.css" rel="stylesheet" type="text/css"/>
<script type="text/javascript" src="jquery.js"></script>
<script type="text/javascript" src="dynsections.js"></script>
<link href="navtree.css" rel="stylesheet" type="text/css"/>
<script type="text/javascript" src="resize.js"></script>
<script type="text/javascript" src="navtreedata.js"></script>
<script type="text/javascript" src="navtree.js"></script>
<script type="text/javascript">
/* @license magnet:?xt=urn:btih:cf05388f2679ee054f2beb29a391d25f4e673ac3&dn=gpl-2.0.txt GPL-v2 */
$(document).ready(initResizable);
/* @license-end */</script>
<link href="doxygen.css" rel="stylesheet" type="text/css" />
</head>
<body>
<div id="top"><!-- do not remove this div, it is closed by doxygen! -->
<div id="titlearea">
<table cellspacing="0" cellpadding="0">
<tbody>
<tr style="height: 56px;">
<td id="projectalign" style="padding-left: 0.5em;">
<div id="projectname">libstdc++
</div>
</td>
</tr>
</tbody>
</table>
</div>
<!-- end header part -->
<!-- Generated by Doxygen 1.8.15 -->
</div><!-- top -->
<div id="side-nav" class="ui-resizable side-nav-resizable">
<div id="nav-tree">
<div id="nav-tree-contents">
<div id="nav-sync" class="sync"></div>
</div>
</div>
<div id="splitbar" style="-moz-user-select:none;"
class="ui-resizable-handle">
</div>
</div>
<script type="text/javascript">
/* @license magnet:?xt=urn:btih:cf05388f2679ee054f2beb29a391d25f4e673ac3&dn=gpl-2.0.txt GPL-v2 */
$(document).ready(function(){initNavTree('a00278_source.html','');});
/* @license-end */
</script>
<div id="doc-content">
<div class="header">
<div class="headertitle">
<div class="title">atomic_futex.h</div> </div>
</div><!--header-->
<div class="contents">
<a href="a00278.html">Go to the documentation of this file.</a><div class="fragment"><div class="line"><a name="l00001"></a><span class="lineno"> 1</span> <span class="comment">// -*- C++ -*- header.</span></div><div class="line"><a name="l00002"></a><span class="lineno"> 2</span> </div><div class="line"><a name="l00003"></a><span class="lineno"> 3</span> <span class="comment">// Copyright (C) 2015-2018 Free Software Foundation, Inc.</span></div><div class="line"><a name="l00004"></a><span class="lineno"> 4</span> <span class="comment">//</span></div><div class="line"><a name="l00005"></a><span class="lineno"> 5</span> <span class="comment">// This file is part of the GNU ISO C++ Library. This library is free</span></div><div class="line"><a name="l00006"></a><span class="lineno"> 6</span> <span class="comment">// software; you can redistribute it and/or modify it under the</span></div><div class="line"><a name="l00007"></a><span class="lineno"> 7</span> <span class="comment">// terms of the GNU General Public License as published by the</span></div><div class="line"><a name="l00008"></a><span class="lineno"> 8</span> <span class="comment">// Free Software Foundation; either version 3, or (at your option)</span></div><div class="line"><a name="l00009"></a><span class="lineno"> 9</span> <span class="comment">// any later version.</span></div><div class="line"><a name="l00010"></a><span class="lineno"> 10</span> </div><div class="line"><a name="l00011"></a><span class="lineno"> 11</span> <span class="comment">// This library is distributed in the hope that it will be useful,</span></div><div class="line"><a name="l00012"></a><span class="lineno"> 12</span> <span class="comment">// but WITHOUT ANY WARRANTY; without even the implied warranty of</span></div><div class="line"><a name="l00013"></a><span class="lineno"> 13</span> <span class="comment">// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the</span></div><div class="line"><a name="l00014"></a><span class="lineno"> 14</span> <span class="comment">// GNU General Public License for more details.</span></div><div class="line"><a name="l00015"></a><span class="lineno"> 15</span> </div><div class="line"><a name="l00016"></a><span class="lineno"> 16</span> <span class="comment">// Under Section 7 of GPL version 3, you are granted additional</span></div><div class="line"><a name="l00017"></a><span class="lineno"> 17</span> <span class="comment">// permissions described in the GCC Runtime Library Exception, version</span></div><div class="line"><a name="l00018"></a><span class="lineno"> 18</span> <span class="comment">// 3.1, as published by the Free Software Foundation.</span></div><div class="line"><a name="l00019"></a><span class="lineno"> 19</span> </div><div class="line"><a name="l00020"></a><span class="lineno"> 20</span> <span class="comment">// You should have received a copy of the GNU General Public License and</span></div><div class="line"><a name="l00021"></a><span class="lineno"> 21</span> <span class="comment">// a copy of the GCC Runtime Library Exception along with this program;</span></div><div class="line"><a name="l00022"></a><span class="lineno"> 22</span> <span class="comment">// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see</span></div><div class="line"><a name="l00023"></a><span class="lineno"> 23</span> <span class="comment">// <http://www.gnu.org/licenses/>.</span></div><div class="line"><a name="l00024"></a><span class="lineno"> 24</span> <span class="comment"></span></div><div class="line"><a name="l00025"></a><span class="lineno"> 25</span> <span class="comment">/** @file bits/atomic_futex.h</span></div><div class="line"><a name="l00026"></a><span class="lineno"> 26</span> <span class="comment"> * This is an internal header file, included by other library headers.</span></div><div class="line"><a name="l00027"></a><span class="lineno"> 27</span> <span class="comment"> * Do not attempt to use it directly.</span></div><div class="line"><a name="l00028"></a><span class="lineno"> 28</span> <span class="comment"> */</span></div><div class="line"><a name="l00029"></a><span class="lineno"> 29</span> </div><div class="line"><a name="l00030"></a><span class="lineno"> 30</span> <span class="preprocessor">#ifndef _GLIBCXX_ATOMIC_FUTEX_H</span></div><div class="line"><a name="l00031"></a><span class="lineno"> 31</span> <span class="preprocessor">#define _GLIBCXX_ATOMIC_FUTEX_H 1</span></div><div class="line"><a name="l00032"></a><span class="lineno"> 32</span> </div><div class="line"><a name="l00033"></a><span class="lineno"> 33</span> <span class="preprocessor">#pragma GCC system_header</span></div><div class="line"><a name="l00034"></a><span class="lineno"> 34</span> </div><div class="line"><a name="l00035"></a><span class="lineno"> 35</span> <span class="preprocessor">#include <<a class="code" href="a00656.html">bits/c++config.h</a>></span></div><div class="line"><a name="l00036"></a><span class="lineno"> 36</span> <span class="preprocessor">#include <<a class="code" href="a00044.html">atomic</a>></span></div><div class="line"><a name="l00037"></a><span class="lineno"> 37</span> <span class="preprocessor">#include <<a class="code" href="a00050.html">chrono</a>></span></div><div class="line"><a name="l00038"></a><span class="lineno"> 38</span> <span class="preprocessor">#if ! (defined(_GLIBCXX_HAVE_LINUX_FUTEX) && ATOMIC_INT_LOCK_FREE > 1)</span></div><div class="line"><a name="l00039"></a><span class="lineno"> 39</span> <span class="preprocessor">#include <<a class="code" href="a00110.html">mutex</a>></span></div><div class="line"><a name="l00040"></a><span class="lineno"> 40</span> <span class="preprocessor">#include <<a class="code" href="a00059.html">condition_variable</a>></span></div><div class="line"><a name="l00041"></a><span class="lineno"> 41</span> <span class="preprocessor">#endif</span></div><div class="line"><a name="l00042"></a><span class="lineno"> 42</span> </div><div class="line"><a name="l00043"></a><span class="lineno"> 43</span> <span class="preprocessor">#ifndef _GLIBCXX_ALWAYS_INLINE</span></div><div class="line"><a name="l00044"></a><span class="lineno"> 44</span> <span class="preprocessor">#define _GLIBCXX_ALWAYS_INLINE inline __attribute__((__always_inline__))</span></div><div class="line"><a name="l00045"></a><span class="lineno"> 45</span> <span class="preprocessor">#endif</span></div><div class="line"><a name="l00046"></a><span class="lineno"> 46</span> </div><div class="line"><a name="l00047"></a><span class="lineno"> 47</span> <span class="keyword">namespace </span><a class="code" href="a01538.html">std</a> _GLIBCXX_VISIBILITY(default)</div><div class="line"><a name="l00048"></a><span class="lineno"> 48</span> {</div><div class="line"><a name="l00049"></a><span class="lineno"> 49</span> _GLIBCXX_BEGIN_NAMESPACE_VERSION</div><div class="line"><a name="l00050"></a><span class="lineno"> 50</span> </div><div class="line"><a name="l00051"></a><span class="lineno"> 51</span> <span class="preprocessor">#if defined(_GLIBCXX_HAS_GTHREADS) && defined(_GLIBCXX_USE_C99_STDINT_TR1)</span></div><div class="line"><a name="l00052"></a><span class="lineno"> 52</span> <span class="preprocessor">#if defined(_GLIBCXX_HAVE_LINUX_FUTEX) && ATOMIC_INT_LOCK_FREE > 1</span></div><div class="line"><a name="l00053"></a><span class="lineno"> 53</span>  <span class="keyword">struct </span>__atomic_futex_unsigned_base</div><div class="line"><a name="l00054"></a><span class="lineno"> 54</span>  {</div><div class="line"><a name="l00055"></a><span class="lineno"> 55</span>  <span class="comment">// Returns false iff a timeout occurred.</span></div><div class="line"><a name="l00056"></a><span class="lineno"> 56</span>  <span class="keywordtype">bool</span></div><div class="line"><a name="l00057"></a><span class="lineno"> 57</span>  _M_futex_wait_until(<span class="keywordtype">unsigned</span> *__addr, <span class="keywordtype">unsigned</span> __val, <span class="keywordtype">bool</span> __has_timeout,</div><div class="line"><a name="l00058"></a><span class="lineno"> 58</span>  <a class="code" href="a01549.html#acc2f93e09fbc239b7a4b48d3c577d0ba">chrono::seconds</a> __s, <a class="code" href="a01549.html#a41d0bd8a6e031eb9321ad13de37723de">chrono::nanoseconds</a> __ns);</div><div class="line"><a name="l00059"></a><span class="lineno"> 59</span> </div><div class="line"><a name="l00060"></a><span class="lineno"> 60</span>  <span class="comment">// This can be executed after the object has been destroyed.</span></div><div class="line"><a name="l00061"></a><span class="lineno"> 61</span>  <span class="keyword">static</span> <span class="keywordtype">void</span> _M_futex_notify_all(<span class="keywordtype">unsigned</span>* __addr);</div><div class="line"><a name="l00062"></a><span class="lineno"> 62</span>  };</div><div class="line"><a name="l00063"></a><span class="lineno"> 63</span> </div><div class="line"><a name="l00064"></a><span class="lineno"> 64</span>  <span class="keyword">template</span> <<span class="keywordtype">unsigned</span> _Waiter_bit = 0x80000000></div><div class="line"><a name="l00065"></a><span class="lineno"> 65</span>  <span class="keyword">class </span>__atomic_futex_unsigned : __atomic_futex_unsigned_base</div><div class="line"><a name="l00066"></a><span class="lineno"> 66</span>  {</div><div class="line"><a name="l00067"></a><span class="lineno"> 67</span>  <span class="keyword">typedef</span> chrono::system_clock __clock_t;</div><div class="line"><a name="l00068"></a><span class="lineno"> 68</span> </div><div class="line"><a name="l00069"></a><span class="lineno"> 69</span>  <span class="comment">// This must be lock-free and at offset 0.</span></div><div class="line"><a name="l00070"></a><span class="lineno"> 70</span>  atomic<unsigned> _M_data;</div><div class="line"><a name="l00071"></a><span class="lineno"> 71</span> </div><div class="line"><a name="l00072"></a><span class="lineno"> 72</span>  <span class="keyword">public</span>:</div><div class="line"><a name="l00073"></a><span class="lineno"> 73</span>  <span class="keyword">explicit</span></div><div class="line"><a name="l00074"></a><span class="lineno"> 74</span>  __atomic_futex_unsigned(<span class="keywordtype">unsigned</span> __data) : _M_data(__data)</div><div class="line"><a name="l00075"></a><span class="lineno"> 75</span>  { }</div><div class="line"><a name="l00076"></a><span class="lineno"> 76</span> </div><div class="line"><a name="l00077"></a><span class="lineno"> 77</span>  _GLIBCXX_ALWAYS_INLINE <span class="keywordtype">unsigned</span></div><div class="line"><a name="l00078"></a><span class="lineno"> 78</span>  _M_load(<a class="code" href="a01485.html#gab4f8c60de95c10793a8e3e27fcb800d9">memory_order</a> __mo)</div><div class="line"><a name="l00079"></a><span class="lineno"> 79</span>  {</div><div class="line"><a name="l00080"></a><span class="lineno"> 80</span>  <span class="keywordflow">return</span> _M_data.load(__mo) & ~_Waiter_bit;</div><div class="line"><a name="l00081"></a><span class="lineno"> 81</span>  }</div><div class="line"><a name="l00082"></a><span class="lineno"> 82</span> </div><div class="line"><a name="l00083"></a><span class="lineno"> 83</span>  <span class="keyword">private</span>:</div><div class="line"><a name="l00084"></a><span class="lineno"> 84</span>  <span class="comment">// If a timeout occurs, returns a current value after the timeout;</span></div><div class="line"><a name="l00085"></a><span class="lineno"> 85</span>  <span class="comment">// otherwise, returns the operand's value if equal is true or a different</span></div><div class="line"><a name="l00086"></a><span class="lineno"> 86</span>  <span class="comment">// value if equal is false.</span></div><div class="line"><a name="l00087"></a><span class="lineno"> 87</span>  <span class="comment">// The assumed value is the caller's assumption about the current value</span></div><div class="line"><a name="l00088"></a><span class="lineno"> 88</span>  <span class="comment">// when making the call.</span></div><div class="line"><a name="l00089"></a><span class="lineno"> 89</span>  <span class="keywordtype">unsigned</span></div><div class="line"><a name="l00090"></a><span class="lineno"> 90</span>  _M_load_and_test_until(<span class="keywordtype">unsigned</span> __assumed, <span class="keywordtype">unsigned</span> __operand,</div><div class="line"><a name="l00091"></a><span class="lineno"> 91</span>  <span class="keywordtype">bool</span> __equal, <a class="code" href="a01485.html#gab4f8c60de95c10793a8e3e27fcb800d9">memory_order</a> __mo, <span class="keywordtype">bool</span> __has_timeout,</div><div class="line"><a name="l00092"></a><span class="lineno"> 92</span>  <a class="code" href="a01549.html#acc2f93e09fbc239b7a4b48d3c577d0ba">chrono::seconds</a> __s, <a class="code" href="a01549.html#a41d0bd8a6e031eb9321ad13de37723de">chrono::nanoseconds</a> __ns)</div><div class="line"><a name="l00093"></a><span class="lineno"> 93</span>  {</div><div class="line"><a name="l00094"></a><span class="lineno"> 94</span>  <span class="keywordflow">for</span> (;;)</div><div class="line"><a name="l00095"></a><span class="lineno"> 95</span>  {</div><div class="line"><a name="l00096"></a><span class="lineno"> 96</span>  <span class="comment">// Don't bother checking the value again because we expect the caller</span></div><div class="line"><a name="l00097"></a><span class="lineno"> 97</span>  <span class="comment">// to have done it recently.</span></div><div class="line"><a name="l00098"></a><span class="lineno"> 98</span>  <span class="comment">// memory_order_relaxed is sufficient because we can rely on just the</span></div><div class="line"><a name="l00099"></a><span class="lineno"> 99</span>  <span class="comment">// modification order (store_notify uses an atomic RMW operation too),</span></div><div class="line"><a name="l00100"></a><span class="lineno"> 100</span>  <span class="comment">// and the futex syscalls synchronize between themselves.</span></div><div class="line"><a name="l00101"></a><span class="lineno"> 101</span>  _M_data.fetch_or(_Waiter_bit, memory_order_relaxed);</div><div class="line"><a name="l00102"></a><span class="lineno"> 102</span>  <span class="keywordtype">bool</span> __ret = _M_futex_wait_until((<span class="keywordtype">unsigned</span>*)(<span class="keywordtype">void</span>*)&_M_data,</div><div class="line"><a name="l00103"></a><span class="lineno"> 103</span>  __assumed | _Waiter_bit,</div><div class="line"><a name="l00104"></a><span class="lineno"> 104</span>  __has_timeout, __s, __ns);</div><div class="line"><a name="l00105"></a><span class="lineno"> 105</span>  <span class="comment">// Fetch the current value after waiting (clears _Waiter_bit).</span></div><div class="line"><a name="l00106"></a><span class="lineno"> 106</span>  __assumed = _M_load(__mo);</div><div class="line"><a name="l00107"></a><span class="lineno"> 107</span>  <span class="keywordflow">if</span> (!__ret || ((__operand == __assumed) == __equal))</div><div class="line"><a name="l00108"></a><span class="lineno"> 108</span>  <span class="keywordflow">return</span> __assumed;</div><div class="line"><a name="l00109"></a><span class="lineno"> 109</span>  <span class="comment">// TODO adapt wait time</span></div><div class="line"><a name="l00110"></a><span class="lineno"> 110</span>  }</div><div class="line"><a name="l00111"></a><span class="lineno"> 111</span>  }</div><div class="line"><a name="l00112"></a><span class="lineno"> 112</span> </div><div class="line"><a name="l00113"></a><span class="lineno"> 113</span>  <span class="comment">// Returns the operand's value if equal is true or a different value if</span></div><div class="line"><a name="l00114"></a><span class="lineno"> 114</span>  <span class="comment">// equal is false.</span></div><div class="line"><a name="l00115"></a><span class="lineno"> 115</span>  <span class="comment">// The assumed value is the caller's assumption about the current value</span></div><div class="line"><a name="l00116"></a><span class="lineno"> 116</span>  <span class="comment">// when making the call.</span></div><div class="line"><a name="l00117"></a><span class="lineno"> 117</span>  <span class="keywordtype">unsigned</span></div><div class="line"><a name="l00118"></a><span class="lineno"> 118</span>  _M_load_and_test(<span class="keywordtype">unsigned</span> __assumed, <span class="keywordtype">unsigned</span> __operand,</div><div class="line"><a name="l00119"></a><span class="lineno"> 119</span>  <span class="keywordtype">bool</span> __equal, <a class="code" href="a01485.html#gab4f8c60de95c10793a8e3e27fcb800d9">memory_order</a> __mo)</div><div class="line"><a name="l00120"></a><span class="lineno"> 120</span>  {</div><div class="line"><a name="l00121"></a><span class="lineno"> 121</span>  <span class="keywordflow">return</span> _M_load_and_test_until(__assumed, __operand, __equal, __mo,</div><div class="line"><a name="l00122"></a><span class="lineno"> 122</span>  <span class="keyword">false</span>, {}, {});</div><div class="line"><a name="l00123"></a><span class="lineno"> 123</span>  }</div><div class="line"><a name="l00124"></a><span class="lineno"> 124</span> </div><div class="line"><a name="l00125"></a><span class="lineno"> 125</span>  <span class="comment">// If a timeout occurs, returns a current value after the timeout;</span></div><div class="line"><a name="l00126"></a><span class="lineno"> 126</span>  <span class="comment">// otherwise, returns the operand's value if equal is true or a different</span></div><div class="line"><a name="l00127"></a><span class="lineno"> 127</span>  <span class="comment">// value if equal is false.</span></div><div class="line"><a name="l00128"></a><span class="lineno"> 128</span>  <span class="comment">// The assumed value is the caller's assumption about the current value</span></div><div class="line"><a name="l00129"></a><span class="lineno"> 129</span>  <span class="comment">// when making the call.</span></div><div class="line"><a name="l00130"></a><span class="lineno"> 130</span>  <span class="keyword">template</span><<span class="keyword">typename</span> _Dur></div><div class="line"><a name="l00131"></a><span class="lineno"> 131</span>  <span class="keywordtype">unsigned</span></div><div class="line"><a name="l00132"></a><span class="lineno"> 132</span>  _M_load_and_test_until_impl(<span class="keywordtype">unsigned</span> __assumed, <span class="keywordtype">unsigned</span> __operand,</div><div class="line"><a name="l00133"></a><span class="lineno"> 133</span>  <span class="keywordtype">bool</span> __equal, <a class="code" href="a01485.html#gab4f8c60de95c10793a8e3e27fcb800d9">memory_order</a> __mo,</div><div class="line"><a name="l00134"></a><span class="lineno"> 134</span>  <span class="keyword">const</span> chrono::time_point<__clock_t, _Dur>& __atime)</div><div class="line"><a name="l00135"></a><span class="lineno"> 135</span>  {</div><div class="line"><a name="l00136"></a><span class="lineno"> 136</span>  <span class="keyword">auto</span> __s = chrono::time_point_cast<chrono::seconds>(__atime);</div><div class="line"><a name="l00137"></a><span class="lineno"> 137</span>  <span class="keyword">auto</span> __ns = chrono::duration_cast<chrono::nanoseconds>(__atime - __s);</div><div class="line"><a name="l00138"></a><span class="lineno"> 138</span>  <span class="comment">// XXX correct?</span></div><div class="line"><a name="l00139"></a><span class="lineno"> 139</span>  <span class="keywordflow">return</span> _M_load_and_test_until(__assumed, __operand, __equal, __mo,</div><div class="line"><a name="l00140"></a><span class="lineno"> 140</span>  <span class="keyword">true</span>, __s.time_since_epoch(), __ns);</div><div class="line"><a name="l00141"></a><span class="lineno"> 141</span>  }</div><div class="line"><a name="l00142"></a><span class="lineno"> 142</span> </div><div class="line"><a name="l00143"></a><span class="lineno"> 143</span>  <span class="keyword">public</span>:</div><div class="line"><a name="l00144"></a><span class="lineno"> 144</span> </div><div class="line"><a name="l00145"></a><span class="lineno"> 145</span>  _GLIBCXX_ALWAYS_INLINE <span class="keywordtype">unsigned</span></div><div class="line"><a name="l00146"></a><span class="lineno"> 146</span>  _M_load_when_not_equal(<span class="keywordtype">unsigned</span> __val, <a class="code" href="a01485.html#gab4f8c60de95c10793a8e3e27fcb800d9">memory_order</a> __mo)</div><div class="line"><a name="l00147"></a><span class="lineno"> 147</span>  {</div><div class="line"><a name="l00148"></a><span class="lineno"> 148</span>  <span class="keywordtype">unsigned</span> __i = _M_load(__mo);</div><div class="line"><a name="l00149"></a><span class="lineno"> 149</span>  <span class="keywordflow">if</span> ((__i & ~_Waiter_bit) != __val)</div><div class="line"><a name="l00150"></a><span class="lineno"> 150</span>  <span class="keywordflow">return</span> (__i & ~_Waiter_bit);</div><div class="line"><a name="l00151"></a><span class="lineno"> 151</span>  <span class="comment">// TODO Spin-wait first.</span></div><div class="line"><a name="l00152"></a><span class="lineno"> 152</span>  <span class="keywordflow">return</span> _M_load_and_test(__i, __val, <span class="keyword">false</span>, __mo);</div><div class="line"><a name="l00153"></a><span class="lineno"> 153</span>  }</div><div class="line"><a name="l00154"></a><span class="lineno"> 154</span> </div><div class="line"><a name="l00155"></a><span class="lineno"> 155</span>  _GLIBCXX_ALWAYS_INLINE <span class="keywordtype">void</span></div><div class="line"><a name="l00156"></a><span class="lineno"> 156</span>  _M_load_when_equal(<span class="keywordtype">unsigned</span> __val, <a class="code" href="a01485.html#gab4f8c60de95c10793a8e3e27fcb800d9">memory_order</a> __mo)</div><div class="line"><a name="l00157"></a><span class="lineno"> 157</span>  {</div><div class="line"><a name="l00158"></a><span class="lineno"> 158</span>  <span class="keywordtype">unsigned</span> __i = _M_load(__mo);</div><div class="line"><a name="l00159"></a><span class="lineno"> 159</span>  <span class="keywordflow">if</span> ((__i & ~_Waiter_bit) == __val)</div><div class="line"><a name="l00160"></a><span class="lineno"> 160</span>  <span class="keywordflow">return</span>;</div><div class="line"><a name="l00161"></a><span class="lineno"> 161</span>  <span class="comment">// TODO Spin-wait first.</span></div><div class="line"><a name="l00162"></a><span class="lineno"> 162</span>  _M_load_and_test(__i, __val, <span class="keyword">true</span>, __mo);</div><div class="line"><a name="l00163"></a><span class="lineno"> 163</span>  }</div><div class="line"><a name="l00164"></a><span class="lineno"> 164</span> </div><div class="line"><a name="l00165"></a><span class="lineno"> 165</span>  <span class="comment">// Returns false iff a timeout occurred.</span></div><div class="line"><a name="l00166"></a><span class="lineno"> 166</span>  <span class="keyword">template</span><<span class="keyword">typename</span> _Rep, <span class="keyword">typename</span> _Period></div><div class="line"><a name="l00167"></a><span class="lineno"> 167</span>  _GLIBCXX_ALWAYS_INLINE <span class="keywordtype">bool</span></div><div class="line"><a name="l00168"></a><span class="lineno"> 168</span>  _M_load_when_equal_for(<span class="keywordtype">unsigned</span> __val, <a class="code" href="a01485.html#gab4f8c60de95c10793a8e3e27fcb800d9">memory_order</a> __mo,</div><div class="line"><a name="l00169"></a><span class="lineno"> 169</span>  <span class="keyword">const</span> chrono::duration<_Rep, _Period>& __rtime)</div><div class="line"><a name="l00170"></a><span class="lineno"> 170</span>  {</div><div class="line"><a name="l00171"></a><span class="lineno"> 171</span>  <span class="keywordflow">return</span> _M_load_when_equal_until(__val, __mo,</div><div class="line"><a name="l00172"></a><span class="lineno"> 172</span>  __clock_t::now() + __rtime);</div><div class="line"><a name="l00173"></a><span class="lineno"> 173</span>  }</div><div class="line"><a name="l00174"></a><span class="lineno"> 174</span> </div><div class="line"><a name="l00175"></a><span class="lineno"> 175</span>  <span class="comment">// Returns false iff a timeout occurred.</span></div><div class="line"><a name="l00176"></a><span class="lineno"> 176</span>  <span class="keyword">template</span><<span class="keyword">typename</span> _Clock, <span class="keyword">typename</span> _Duration></div><div class="line"><a name="l00177"></a><span class="lineno"> 177</span>  _GLIBCXX_ALWAYS_INLINE <span class="keywordtype">bool</span></div><div class="line"><a name="l00178"></a><span class="lineno"> 178</span>  _M_load_when_equal_until(<span class="keywordtype">unsigned</span> __val, <a class="code" href="a01485.html#gab4f8c60de95c10793a8e3e27fcb800d9">memory_order</a> __mo,</div><div class="line"><a name="l00179"></a><span class="lineno"> 179</span>  <span class="keyword">const</span> chrono::time_point<_Clock, _Duration>& __atime)</div><div class="line"><a name="l00180"></a><span class="lineno"> 180</span>  {</div><div class="line"><a name="l00181"></a><span class="lineno"> 181</span>  <span class="comment">// DR 887 - Sync unknown clock to known clock.</span></div><div class="line"><a name="l00182"></a><span class="lineno"> 182</span>  <span class="keyword">const</span> <span class="keyword">typename</span> _Clock::time_point __c_entry = _Clock::now();</div><div class="line"><a name="l00183"></a><span class="lineno"> 183</span>  <span class="keyword">const</span> __clock_t::time_point __s_entry = __clock_t::now();</div><div class="line"><a name="l00184"></a><span class="lineno"> 184</span>  <span class="keyword">const</span> <span class="keyword">auto</span> __delta = __atime - __c_entry;</div><div class="line"><a name="l00185"></a><span class="lineno"> 185</span>  <span class="keyword">const</span> <span class="keyword">auto</span> __s_atime = __s_entry + __delta;</div><div class="line"><a name="l00186"></a><span class="lineno"> 186</span>  <span class="keywordflow">return</span> _M_load_when_equal_until(__val, __mo, __s_atime);</div><div class="line"><a name="l00187"></a><span class="lineno"> 187</span>  }</div><div class="line"><a name="l00188"></a><span class="lineno"> 188</span> </div><div class="line"><a name="l00189"></a><span class="lineno"> 189</span>  <span class="comment">// Returns false iff a timeout occurred.</span></div><div class="line"><a name="l00190"></a><span class="lineno"> 190</span>  <span class="keyword">template</span><<span class="keyword">typename</span> _Duration></div><div class="line"><a name="l00191"></a><span class="lineno"> 191</span>  _GLIBCXX_ALWAYS_INLINE <span class="keywordtype">bool</span></div><div class="line"><a name="l00192"></a><span class="lineno"> 192</span>  _M_load_when_equal_until(<span class="keywordtype">unsigned</span> __val, <a class="code" href="a01485.html#gab4f8c60de95c10793a8e3e27fcb800d9">memory_order</a> __mo,</div><div class="line"><a name="l00193"></a><span class="lineno"> 193</span>  <span class="keyword">const</span> chrono::time_point<__clock_t, _Duration>& __atime)</div><div class="line"><a name="l00194"></a><span class="lineno"> 194</span>  {</div><div class="line"><a name="l00195"></a><span class="lineno"> 195</span>  <span class="keywordtype">unsigned</span> __i = _M_load(__mo);</div><div class="line"><a name="l00196"></a><span class="lineno"> 196</span>  <span class="keywordflow">if</span> ((__i & ~_Waiter_bit) == __val)</div><div class="line"><a name="l00197"></a><span class="lineno"> 197</span>  <span class="keywordflow">return</span> <span class="keyword">true</span>;</div><div class="line"><a name="l00198"></a><span class="lineno"> 198</span>  <span class="comment">// TODO Spin-wait first. Ignore effect on timeout.</span></div><div class="line"><a name="l00199"></a><span class="lineno"> 199</span>  __i = _M_load_and_test_until_impl(__i, __val, <span class="keyword">true</span>, __mo, __atime);</div><div class="line"><a name="l00200"></a><span class="lineno"> 200</span>  <span class="keywordflow">return</span> (__i & ~_Waiter_bit) == __val;</div><div class="line"><a name="l00201"></a><span class="lineno"> 201</span>  }</div><div class="line"><a name="l00202"></a><span class="lineno"> 202</span> </div><div class="line"><a name="l00203"></a><span class="lineno"> 203</span>  _GLIBCXX_ALWAYS_INLINE <span class="keywordtype">void</span></div><div class="line"><a name="l00204"></a><span class="lineno"> 204</span>  _M_store_notify_all(<span class="keywordtype">unsigned</span> __val, <a class="code" href="a01485.html#gab4f8c60de95c10793a8e3e27fcb800d9">memory_order</a> __mo)</div><div class="line"><a name="l00205"></a><span class="lineno"> 205</span>  {</div><div class="line"><a name="l00206"></a><span class="lineno"> 206</span>  <span class="keywordtype">unsigned</span>* __futex = (<span class="keywordtype">unsigned</span> *)(<span class="keywordtype">void</span> *)&_M_data;</div><div class="line"><a name="l00207"></a><span class="lineno"> 207</span>  <span class="keywordflow">if</span> (_M_data.exchange(__val, __mo) & _Waiter_bit)</div><div class="line"><a name="l00208"></a><span class="lineno"> 208</span>  _M_futex_notify_all(__futex);</div><div class="line"><a name="l00209"></a><span class="lineno"> 209</span>  }</div><div class="line"><a name="l00210"></a><span class="lineno"> 210</span>  };</div><div class="line"><a name="l00211"></a><span class="lineno"> 211</span> </div><div class="line"><a name="l00212"></a><span class="lineno"> 212</span> <span class="preprocessor">#else // ! (_GLIBCXX_HAVE_LINUX_FUTEX && ATOMIC_INT_LOCK_FREE > 1)</span></div><div class="line"><a name="l00213"></a><span class="lineno"> 213</span> </div><div class="line"><a name="l00214"></a><span class="lineno"> 214</span>  <span class="comment">// If futexes are not available, use a mutex and a condvar to wait.</span></div><div class="line"><a name="l00215"></a><span class="lineno"> 215</span>  <span class="comment">// Because we access the data only within critical sections, all accesses</span></div><div class="line"><a name="l00216"></a><span class="lineno"> 216</span>  <span class="comment">// are sequentially consistent; thus, we satisfy any provided memory_order.</span></div><div class="line"><a name="l00217"></a><span class="lineno"> 217</span>  <span class="keyword">template</span> <<span class="keywordtype">unsigned</span> _Waiter_bit = 0x80000000></div><div class="line"><a name="l00218"></a><span class="lineno"> 218</span>  <span class="keyword">class </span>__atomic_futex_unsigned</div><div class="line"><a name="l00219"></a><span class="lineno"> 219</span>  {</div><div class="line"><a name="l00220"></a><span class="lineno"> 220</span>  <span class="keyword">typedef</span> chrono::system_clock __clock_t;</div><div class="line"><a name="l00221"></a><span class="lineno"> 221</span> </div><div class="line"><a name="l00222"></a><span class="lineno"> 222</span>  <span class="keywordtype">unsigned</span> _M_data;</div><div class="line"><a name="l00223"></a><span class="lineno"> 223</span>  mutex _M_mutex;</div><div class="line"><a name="l00224"></a><span class="lineno"> 224</span>  condition_variable _M_condvar;</div><div class="line"><a name="l00225"></a><span class="lineno"> 225</span> </div><div class="line"><a name="l00226"></a><span class="lineno"> 226</span>  <span class="keyword">public</span>:</div><div class="line"><a name="l00227"></a><span class="lineno"> 227</span>  <span class="keyword">explicit</span></div><div class="line"><a name="l00228"></a><span class="lineno"> 228</span>  __atomic_futex_unsigned(<span class="keywordtype">unsigned</span> __data) : _M_data(__data)</div><div class="line"><a name="l00229"></a><span class="lineno"> 229</span>  { }</div><div class="line"><a name="l00230"></a><span class="lineno"> 230</span> </div><div class="line"><a name="l00231"></a><span class="lineno"> 231</span>  _GLIBCXX_ALWAYS_INLINE <span class="keywordtype">unsigned</span></div><div class="line"><a name="l00232"></a><span class="lineno"> 232</span>  _M_load(<a class="code" href="a01485.html#gab4f8c60de95c10793a8e3e27fcb800d9">memory_order</a> __mo)</div><div class="line"><a name="l00233"></a><span class="lineno"> 233</span>  {</div><div class="line"><a name="l00234"></a><span class="lineno"> 234</span>  unique_lock<mutex> __lock(_M_mutex);</div><div class="line"><a name="l00235"></a><span class="lineno"> 235</span>  <span class="keywordflow">return</span> _M_data;</div><div class="line"><a name="l00236"></a><span class="lineno"> 236</span>  }</div><div class="line"><a name="l00237"></a><span class="lineno"> 237</span> </div><div class="line"><a name="l00238"></a><span class="lineno"> 238</span>  _GLIBCXX_ALWAYS_INLINE <span class="keywordtype">unsigned</span></div><div class="line"><a name="l00239"></a><span class="lineno"> 239</span>  _M_load_when_not_equal(<span class="keywordtype">unsigned</span> __val, <a class="code" href="a01485.html#gab4f8c60de95c10793a8e3e27fcb800d9">memory_order</a> __mo)</div><div class="line"><a name="l00240"></a><span class="lineno"> 240</span>  {</div><div class="line"><a name="l00241"></a><span class="lineno"> 241</span>  unique_lock<mutex> __lock(_M_mutex);</div><div class="line"><a name="l00242"></a><span class="lineno"> 242</span>  <span class="keywordflow">while</span> (_M_data == __val)</div><div class="line"><a name="l00243"></a><span class="lineno"> 243</span>  _M_condvar.wait(__lock);</div><div class="line"><a name="l00244"></a><span class="lineno"> 244</span>  <span class="keywordflow">return</span> _M_data;</div><div class="line"><a name="l00245"></a><span class="lineno"> 245</span>  }</div><div class="line"><a name="l00246"></a><span class="lineno"> 246</span> </div><div class="line"><a name="l00247"></a><span class="lineno"> 247</span>  _GLIBCXX_ALWAYS_INLINE <span class="keywordtype">void</span></div><div class="line"><a name="l00248"></a><span class="lineno"> 248</span>  _M_load_when_equal(<span class="keywordtype">unsigned</span> __val, <a class="code" href="a01485.html#gab4f8c60de95c10793a8e3e27fcb800d9">memory_order</a> __mo)</div><div class="line"><a name="l00249"></a><span class="lineno"> 249</span>  {</div><div class="line"><a name="l00250"></a><span class="lineno"> 250</span>  unique_lock<mutex> __lock(_M_mutex);</div><div class="line"><a name="l00251"></a><span class="lineno"> 251</span>  <span class="keywordflow">while</span> (_M_data != __val)</div><div class="line"><a name="l00252"></a><span class="lineno"> 252</span>  _M_condvar.wait(__lock);</div><div class="line"><a name="l00253"></a><span class="lineno"> 253</span>  }</div><div class="line"><a name="l00254"></a><span class="lineno"> 254</span> </div><div class="line"><a name="l00255"></a><span class="lineno"> 255</span>  <span class="keyword">template</span><<span class="keyword">typename</span> _Rep, <span class="keyword">typename</span> _Period></div><div class="line"><a name="l00256"></a><span class="lineno"> 256</span>  _GLIBCXX_ALWAYS_INLINE <span class="keywordtype">bool</span></div><div class="line"><a name="l00257"></a><span class="lineno"> 257</span>  _M_load_when_equal_for(<span class="keywordtype">unsigned</span> __val, <a class="code" href="a01485.html#gab4f8c60de95c10793a8e3e27fcb800d9">memory_order</a> __mo,</div><div class="line"><a name="l00258"></a><span class="lineno"> 258</span>  <span class="keyword">const</span> chrono::duration<_Rep, _Period>& __rtime)</div><div class="line"><a name="l00259"></a><span class="lineno"> 259</span>  {</div><div class="line"><a name="l00260"></a><span class="lineno"> 260</span>  unique_lock<mutex> __lock(_M_mutex);</div><div class="line"><a name="l00261"></a><span class="lineno"> 261</span>  <span class="keywordflow">return</span> _M_condvar.wait_for(__lock, __rtime,</div><div class="line"><a name="l00262"></a><span class="lineno"> 262</span>  [&] { <span class="keywordflow">return</span> _M_data == __val;});</div><div class="line"><a name="l00263"></a><span class="lineno"> 263</span>  }</div><div class="line"><a name="l00264"></a><span class="lineno"> 264</span> </div><div class="line"><a name="l00265"></a><span class="lineno"> 265</span>  <span class="keyword">template</span><<span class="keyword">typename</span> _Clock, <span class="keyword">typename</span> _Duration></div><div class="line"><a name="l00266"></a><span class="lineno"> 266</span>  _GLIBCXX_ALWAYS_INLINE <span class="keywordtype">bool</span></div><div class="line"><a name="l00267"></a><span class="lineno"> 267</span>  _M_load_when_equal_until(<span class="keywordtype">unsigned</span> __val, <a class="code" href="a01485.html#gab4f8c60de95c10793a8e3e27fcb800d9">memory_order</a> __mo,</div><div class="line"><a name="l00268"></a><span class="lineno"> 268</span>  <span class="keyword">const</span> chrono::time_point<_Clock, _Duration>& __atime)</div><div class="line"><a name="l00269"></a><span class="lineno"> 269</span>  {</div><div class="line"><a name="l00270"></a><span class="lineno"> 270</span>  unique_lock<mutex> __lock(_M_mutex);</div><div class="line"><a name="l00271"></a><span class="lineno"> 271</span>  <span class="keywordflow">return</span> _M_condvar.wait_until(__lock, __atime,</div><div class="line"><a name="l00272"></a><span class="lineno"> 272</span>  [&] { <span class="keywordflow">return</span> _M_data == __val;});</div><div class="line"><a name="l00273"></a><span class="lineno"> 273</span>  }</div><div class="line"><a name="l00274"></a><span class="lineno"> 274</span> </div><div class="line"><a name="l00275"></a><span class="lineno"> 275</span>  _GLIBCXX_ALWAYS_INLINE <span class="keywordtype">void</span></div><div class="line"><a name="l00276"></a><span class="lineno"> 276</span>  _M_store_notify_all(<span class="keywordtype">unsigned</span> __val, <a class="code" href="a01485.html#gab4f8c60de95c10793a8e3e27fcb800d9">memory_order</a> __mo)</div><div class="line"><a name="l00277"></a><span class="lineno"> 277</span>  {</div><div class="line"><a name="l00278"></a><span class="lineno"> 278</span>  unique_lock<mutex> __lock(_M_mutex);</div><div class="line"><a name="l00279"></a><span class="lineno"> 279</span>  _M_data = __val;</div><div class="line"><a name="l00280"></a><span class="lineno"> 280</span>  _M_condvar.notify_all();</div><div class="line"><a name="l00281"></a><span class="lineno"> 281</span>  }</div><div class="line"><a name="l00282"></a><span class="lineno"> 282</span>  };</div><div class="line"><a name="l00283"></a><span class="lineno"> 283</span> </div><div class="line"><a name="l00284"></a><span class="lineno"> 284</span> <span class="preprocessor">#endif // _GLIBCXX_HAVE_LINUX_FUTEX && ATOMIC_INT_LOCK_FREE > 1</span></div><div class="line"><a name="l00285"></a><span class="lineno"> 285</span> <span class="preprocessor">#endif // _GLIBCXX_HAS_GTHREADS && _GLIBCXX_USE_C99_STDINT_TR1</span></div><div class="line"><a name="l00286"></a><span class="lineno"> 286</span> </div><div class="line"><a name="l00287"></a><span class="lineno"> 287</span> _GLIBCXX_END_NAMESPACE_VERSION</div><div class="line"><a name="l00288"></a><span class="lineno"> 288</span> } <span class="comment">// namespace std</span></div><div class="line"><a name="l00289"></a><span class="lineno"> 289</span> </div><div class="line"><a name="l00290"></a><span class="lineno"> 290</span> <span class="preprocessor">#endif</span></div><div class="ttc" id="a01485_html_gab4f8c60de95c10793a8e3e27fcb800d9"><div class="ttname"><a href="a01485.html#gab4f8c60de95c10793a8e3e27fcb800d9">std::memory_order</a></div><div class="ttdeci">memory_order</div><div class="ttdoc">Enumeration for memory_order.</div><div class="ttdef"><b>Definition:</b> <a href="a00275_source.html#l00055">atomic_base.h:55</a></div></div>
<div class="ttc" id="a00110_html"><div class="ttname"><a href="a00110.html">mutex</a></div></div>
<div class="ttc" id="a00656_html"><div class="ttname"><a href="a00656.html">c++config.h</a></div></div>
<div class="ttc" id="a00044_html"><div class="ttname"><a href="a00044.html">atomic</a></div></div>
<div class="ttc" id="a00059_html"><div class="ttname"><a href="a00059.html">condition_variable</a></div></div>
<div class="ttc" id="a00050_html"><div class="ttname"><a href="a00050.html">chrono</a></div></div>
<div class="ttc" id="a01549_html_a41d0bd8a6e031eb9321ad13de37723de"><div class="ttname"><a href="a01549.html#a41d0bd8a6e031eb9321ad13de37723de">std::chrono::nanoseconds</a></div><div class="ttdeci">duration< int64_t, nano > nanoseconds</div><div class="ttdoc">nanoseconds</div><div class="ttdef"><b>Definition:</b> <a href="a00050_source.html#l00597">chrono:597</a></div></div>
<div class="ttc" id="a01538_html"><div class="ttname"><a href="a01538.html">std</a></div><div class="ttdoc">ISO C++ entities toplevel namespace is std.</div></div>
<div class="ttc" id="a01549_html_acc2f93e09fbc239b7a4b48d3c577d0ba"><div class="ttname"><a href="a01549.html#acc2f93e09fbc239b7a4b48d3c577d0ba">std::chrono::seconds</a></div><div class="ttdeci">duration< int64_t > seconds</div><div class="ttdoc">seconds</div><div class="ttdef"><b>Definition:</b> <a href="a00050_source.html#l00606">chrono:606</a></div></div>
</div><!-- fragment --></div><!-- contents -->
</div><!-- doc-content -->
<!-- start footer part -->
<div id="nav-path" class="navpath"><!-- id is needed for treeview function! -->
<ul>
<li class="navelem"><a class="el" href="dir_3a83f109ff04170a1f8448445d1bdcba.html">include</a></li><li class="navelem"><a class="el" href="dir_599c955538774c0249d4ddd97c0a9ae8.html">bits</a></li><li class="navelem"><a class="el" href="a00278.html">atomic_futex.h</a></li>
<li class="footer">Generated by
<a href="http://www.doxygen.org/index.html">
<img class="footer" src="doxygen.png" alt="doxygen"/></a> 1.8.15 </li>
</ul>
</div>
</body>
</html>
distrib
>
Mageia
>
7
>
armv7hl
>
media
>
core-updates
>
by-pkgid
>
0448c66ab6afa2f787658c5e6488e2d9
>
files
>
269
