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  36   <div class="section" id="locks">
  37 <h1>Locks<a class="headerlink" href="#locks" title="Permalink to this headline">¶</a></h1>
  38 <p>An API for creating and using a software lock/mutex. </p>
  39 <div class="breathe-sectiondef docutils container">
  40 <p class="breathe-sectiondef-title rubric">Defines</p>
  41 <dl class="macro">
  42 <dt id="c.METAL_LOCK_DECLARE">
  43 <span class="target" id="lock_8h_1ab374ff07975df10c0dd028439b351af9"></span><code class="descname">METAL_LOCK_DECLARE</code><span class="sig-paren">(</span>name<span class="sig-paren">)</span><a class="headerlink" href="#c.METAL_LOCK_DECLARE" title="Permalink to this definition">¶</a></dt>
  44 <dd><p>Declare a lock. </p>
  45 <p>Locks must be declared with METAL_LOCK_DECLARE to ensure that the lock is linked into a memory region which supports atomic memory operations. </p>
  46 </dd></dl>
  47
  48 </div>
  49 <div class="breathe-sectiondef docutils container">
  50 <p class="breathe-sectiondef-title rubric">Functions</p>
  51 <dl class="function">
  52 <dt id="_CPPv315metal_lock_initP10metal_lock">
  53 <span id="_CPPv215metal_lock_initP10metal_lock"></span><span id="metal_lock_init__metal_lockP"></span><span class="target" id="lock_8h_1ac6c3769091eb4746302c9c5c9b42050c"></span>int <code class="descname">metal_lock_init</code><span class="sig-paren">(</span><em class="property">struct</em> <a class="reference internal" href="#_CPPv310metal_lock" title="metal_lock">metal_lock</a> *<em>lock</em><span class="sig-paren">)</span><a class="headerlink" href="#_CPPv315metal_lock_initP10metal_lock" title="Permalink to this definition">¶</a><br /></dt>
  54 <dd><p>Initialize a lock. </p>
  55 <p><p>If the lock cannot be initialized, attempts to take or give the lock will result in a Store/AMO access fault. </p>
  56 <dl class="docutils">
  57 <dt><strong>Return</strong></dt>
  58 <dd>0 if the lock is successfully initialized. A non-zero code indicates failure.</dd>
  59 <dt><strong>Parameters</strong></dt>
  60 <dd><ul class="breatheparameterlist first last simple">
  61 <li><code class="docutils literal notranslate"><span class="pre">lock</span></code>: The handle for a lock </li>
  62 </ul>
  63 </dd>
  64 </dl>
  65 </p>
  66 </dd></dl>
  67
  68 <dl class="function">
  69 <dt id="_CPPv315metal_lock_takeP10metal_lock">
  70 <span id="_CPPv215metal_lock_takeP10metal_lock"></span><span id="metal_lock_take__metal_lockP"></span><span class="target" id="lock_8h_1a62f98dd8920e3e1dcab6e87763a0e413"></span>int <code class="descname">metal_lock_take</code><span class="sig-paren">(</span><em class="property">struct</em> <a class="reference internal" href="#_CPPv310metal_lock" title="metal_lock">metal_lock</a> *<em>lock</em><span class="sig-paren">)</span><a class="headerlink" href="#_CPPv315metal_lock_takeP10metal_lock" title="Permalink to this definition">¶</a><br /></dt>
  71 <dd><p>Take a lock. </p>
  72 <p><p>If the lock initialization failed, attempts to take a lock will result in a Store/AMO access fault. </p>
  73 <dl class="docutils">
  74 <dt><strong>Return</strong></dt>
  75 <dd>0 if the lock is successfully taken</dd>
  76 <dt><strong>Parameters</strong></dt>
  77 <dd><ul class="breatheparameterlist first last simple">
  78 <li><code class="docutils literal notranslate"><span class="pre">lock</span></code>: The handle for a lock </li>
  79 </ul>
  80 </dd>
  81 </dl>
  82 </p>
  83 </dd></dl>
  84
  85 <dl class="function">
  86 <dt id="_CPPv315metal_lock_giveP10metal_lock">
  87 <span id="_CPPv215metal_lock_giveP10metal_lock"></span><span id="metal_lock_give__metal_lockP"></span><span class="target" id="lock_8h_1a2a107fe4f7faea16bb3f98e572dc480b"></span>int <code class="descname">metal_lock_give</code><span class="sig-paren">(</span><em class="property">struct</em> <a class="reference internal" href="#_CPPv310metal_lock" title="metal_lock">metal_lock</a> *<em>lock</em><span class="sig-paren">)</span><a class="headerlink" href="#_CPPv315metal_lock_giveP10metal_lock" title="Permalink to this definition">¶</a><br /></dt>
  88 <dd><p>Give back a held lock. </p>
  89 <p><p>If the lock initialization failed, attempts to give a lock will result in a Store/AMO access fault. </p>
  90 <dl class="docutils">
  91 <dt><strong>Return</strong></dt>
  92 <dd>0 if the lock is successfully given</dd>
  93 <dt><strong>Parameters</strong></dt>
  94 <dd><ul class="breatheparameterlist first last simple">
  95 <li><code class="docutils literal notranslate"><span class="pre">lock</span></code>: The handle for a lock </li>
  96 </ul>
  97 </dd>
  98 </dl>
  99 </p>
 100 </dd></dl>
 101
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 103 <dl class="class">
 104 <dt id="_CPPv310metal_lock">
 105 <span id="_CPPv210metal_lock"></span><span id="metal_lock"></span><span class="target" id="structmetal__lock"></span><em class="property">struct </em><code class="descname">metal_lock</code><a class="headerlink" href="#_CPPv310metal_lock" title="Permalink to this definition">¶</a><br /></dt>
 106 <dd><em>#include &lt;lock.h&gt;</em><p>A handle for a lock. </p>
 107 </dd></dl>
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