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 103
 104 <div class="header">
 105   <div class="summary">
 106 <a href="#func-members">Functions</a>  </div>
 107   <div class="headertitle"><div class="title">critical_section<div class="ingroups"><a class="el" href="group__high__level.html">High Level APIs</a> &raquo; <a class="el" href="group__pico__sync.html">pico_sync</a></div></div></div>
 108 </div><!--header-->
 109 <div class="contents">
 110
 111 <p>Critical Section API for short-lived mutual exclusion safe for IRQ and multi-core.
 112 <a href="#details">More...</a></p>
 113 <table class="memberdecls">
 114 <tr class="heading"><td colspan="2"><h2 class="groupheader"><a id="func-members" name="func-members"></a>
 115 Functions</h2></td></tr>
 116 <tr class="memitem:ga22cd2722a96179036820e87b29209cfd"><td class="memItemLeft" align="right" valign="top">void&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="group__critical__section.html#ga22cd2722a96179036820e87b29209cfd">critical_section_init</a> (critical_section_t *crit_sec)</td></tr>
 117 <tr class="memdesc:ga22cd2722a96179036820e87b29209cfd"><td class="mdescLeft">&#160;</td><td class="mdescRight">Initialise a <a class="el" href="structcritical__section.html">critical_section</a> structure allowing the system to assign a spin lock number.  <a href="group__critical__section.html#ga22cd2722a96179036820e87b29209cfd">More...</a><br /></td></tr>
 118 <tr class="separator:ga22cd2722a96179036820e87b29209cfd"><td class="memSeparator" colspan="2">&#160;</td></tr>
 119 <tr class="memitem:gae1b4eb5dcab9ac679970ac43d618de2c"><td class="memItemLeft" align="right" valign="top">void&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="group__critical__section.html#gae1b4eb5dcab9ac679970ac43d618de2c">critical_section_init_with_lock_num</a> (critical_section_t *crit_sec, uint lock_num)</td></tr>
 120 <tr class="memdesc:gae1b4eb5dcab9ac679970ac43d618de2c"><td class="mdescLeft">&#160;</td><td class="mdescRight">Initialise a <a class="el" href="structcritical__section.html">critical_section</a> structure assigning a specific spin lock number.  <a href="group__critical__section.html#gae1b4eb5dcab9ac679970ac43d618de2c">More...</a><br /></td></tr>
 121 <tr class="separator:gae1b4eb5dcab9ac679970ac43d618de2c"><td class="memSeparator" colspan="2">&#160;</td></tr>
 122 <tr class="memitem:ga15e4552b4e1419faad51eba026a39aad"><td class="memItemLeft" align="right" valign="top">static void&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="group__critical__section.html#ga15e4552b4e1419faad51eba026a39aad">critical_section_enter_blocking</a> (critical_section_t *crit_sec)</td></tr>
 123 <tr class="memdesc:ga15e4552b4e1419faad51eba026a39aad"><td class="mdescLeft">&#160;</td><td class="mdescRight">Enter a <a class="el" href="structcritical__section.html">critical_section</a>.  <a href="group__critical__section.html#ga15e4552b4e1419faad51eba026a39aad">More...</a><br /></td></tr>
 124 <tr class="separator:ga15e4552b4e1419faad51eba026a39aad"><td class="memSeparator" colspan="2">&#160;</td></tr>
 125 <tr class="memitem:gab57fcee3973b26dced4601e6018a227c"><td class="memItemLeft" align="right" valign="top">static void&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="group__critical__section.html#gab57fcee3973b26dced4601e6018a227c">critical_section_exit</a> (critical_section_t *crit_sec)</td></tr>
 126 <tr class="memdesc:gab57fcee3973b26dced4601e6018a227c"><td class="mdescLeft">&#160;</td><td class="mdescRight">Release a <a class="el" href="structcritical__section.html">critical_section</a>.  <a href="group__critical__section.html#gab57fcee3973b26dced4601e6018a227c">More...</a><br /></td></tr>
 127 <tr class="separator:gab57fcee3973b26dced4601e6018a227c"><td class="memSeparator" colspan="2">&#160;</td></tr>
 128 <tr class="memitem:ga08444ba7879fae8813dd5573a13f0351"><td class="memItemLeft" align="right" valign="top">void&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="group__critical__section.html#ga08444ba7879fae8813dd5573a13f0351">critical_section_deinit</a> (critical_section_t *crit_sec)</td></tr>
 129 <tr class="memdesc:ga08444ba7879fae8813dd5573a13f0351"><td class="mdescLeft">&#160;</td><td class="mdescRight">De-Initialise a <a class="el" href="structcritical__section.html">critical_section</a> created by the critical_section_init method.  <a href="group__critical__section.html#ga08444ba7879fae8813dd5573a13f0351">More...</a><br /></td></tr>
 130 <tr class="separator:ga08444ba7879fae8813dd5573a13f0351"><td class="memSeparator" colspan="2">&#160;</td></tr>
 131 </table>
 132 <a name="details" id="details"></a><h2 class="groupheader">Detailed Description</h2>
 133 <p >Critical Section API for short-lived mutual exclusion safe for IRQ and multi-core. </p>
 134 <p >A critical section is non-reentrant, and provides mutual exclusion using a spin-lock to prevent access from the other core, and from (higher priority) interrupts on the same core. It does the former using a spin lock and the latter by disabling interrupts on the calling core.</p>
 135 <p >Because interrupts are disabled when a <a class="el" href="structcritical__section.html">critical_section</a> is owned, uses of the <a class="el" href="structcritical__section.html">critical_section</a> should be as short as possible. </p>
 136 <h2 class="groupheader">Function Documentation</h2>
 137 <a id="ga08444ba7879fae8813dd5573a13f0351" name="ga08444ba7879fae8813dd5573a13f0351"></a>
 138 <h2 class="memtitle"><span class="permalink"><a href="#ga08444ba7879fae8813dd5573a13f0351">&#9670;&nbsp;</a></span>critical_section_deinit()</h2>
 139
 140 <div class="memitem">
 141 <div class="memproto">
 142       <table class="memname">
 143         <tr>
 144           <td class="memname">void critical_section_deinit </td>
 145           <td>(</td>
 146           <td class="paramtype">critical_section_t *&#160;</td>
 147           <td class="paramname"><em>crit_sec</em></td><td>)</td>
 148           <td></td>
 149         </tr>
 150       </table>
 151 </div><div class="memdoc">
 152
 153 <p>De-Initialise a <a class="el" href="structcritical__section.html">critical_section</a> created by the critical_section_init method. </p>
 154 <p >This method is only used to free the associated spin lock allocated via the critical_section_init method (it should not be used to de-initialize a spin lock created via critical_section_init_with_lock_num). After this call, the critical section is invalid</p>
 155 <dl class="params"><dt>Parameters</dt><dd>
 156   <table class="params">
 157     <tr><td class="paramname">crit_sec</td><td>Pointer to <a class="el" href="structcritical__section.html">critical_section</a> structure </td></tr>
 158   </table>
 159   </dd>
 160 </dl>
 161
 162 </div>
 163 </div>
 164 <a id="ga15e4552b4e1419faad51eba026a39aad" name="ga15e4552b4e1419faad51eba026a39aad"></a>
 165 <h2 class="memtitle"><span class="permalink"><a href="#ga15e4552b4e1419faad51eba026a39aad">&#9670;&nbsp;</a></span>critical_section_enter_blocking()</h2>
 166
 167 <div class="memitem">
 168 <div class="memproto">
 169 <table class="mlabels">
 170   <tr>
 171   <td class="mlabels-left">
 172       <table class="memname">
 173         <tr>
 174           <td class="memname">static void critical_section_enter_blocking </td>
 175           <td>(</td>
 176           <td class="paramtype">critical_section_t *&#160;</td>
 177           <td class="paramname"><em>crit_sec</em></td><td>)</td>
 178           <td></td>
 179         </tr>
 180       </table>
 181   </td>
 182   <td class="mlabels-right">
 183 <span class="mlabels"><span class="mlabel">inline</span><span class="mlabel">static</span></span>  </td>
 184   </tr>
 185 </table>
 186 </div><div class="memdoc">
 187
 188 <p>Enter a <a class="el" href="structcritical__section.html">critical_section</a>. </p>
 189 <p >If the spin lock associated with this critical section is in use, then this method will block until it is released.</p>
 190 <dl class="params"><dt>Parameters</dt><dd>
 191   <table class="params">
 192     <tr><td class="paramname">crit_sec</td><td>Pointer to <a class="el" href="structcritical__section.html">critical_section</a> structure </td></tr>
 193   </table>
 194   </dd>
 195 </dl>
 196
 197 </div>
 198 </div>
 199 <a id="gab57fcee3973b26dced4601e6018a227c" name="gab57fcee3973b26dced4601e6018a227c"></a>
 200 <h2 class="memtitle"><span class="permalink"><a href="#gab57fcee3973b26dced4601e6018a227c">&#9670;&nbsp;</a></span>critical_section_exit()</h2>
 201
 202 <div class="memitem">
 203 <div class="memproto">
 204 <table class="mlabels">
 205   <tr>
 206   <td class="mlabels-left">
 207       <table class="memname">
 208         <tr>
 209           <td class="memname">static void critical_section_exit </td>
 210           <td>(</td>
 211           <td class="paramtype">critical_section_t *&#160;</td>
 212           <td class="paramname"><em>crit_sec</em></td><td>)</td>
 213           <td></td>
 214         </tr>
 215       </table>
 216   </td>
 217   <td class="mlabels-right">
 218 <span class="mlabels"><span class="mlabel">inline</span><span class="mlabel">static</span></span>  </td>
 219   </tr>
 220 </table>
 221 </div><div class="memdoc">
 222
 223 <p>Release a <a class="el" href="structcritical__section.html">critical_section</a>. </p>
 224 <dl class="params"><dt>Parameters</dt><dd>
 225   <table class="params">
 226     <tr><td class="paramname">crit_sec</td><td>Pointer to <a class="el" href="structcritical__section.html">critical_section</a> structure </td></tr>
 227   </table>
 228   </dd>
 229 </dl>
 230
 231 </div>
 232 </div>
 233 <a id="ga22cd2722a96179036820e87b29209cfd" name="ga22cd2722a96179036820e87b29209cfd"></a>
 234 <h2 class="memtitle"><span class="permalink"><a href="#ga22cd2722a96179036820e87b29209cfd">&#9670;&nbsp;</a></span>critical_section_init()</h2>
 235
 236 <div class="memitem">
 237 <div class="memproto">
 238       <table class="memname">
 239         <tr>
 240           <td class="memname">void critical_section_init </td>
 241           <td>(</td>
 242           <td class="paramtype">critical_section_t *&#160;</td>
 243           <td class="paramname"><em>crit_sec</em></td><td>)</td>
 244           <td></td>
 245         </tr>
 246       </table>
 247 </div><div class="memdoc">
 248
 249 <p>Initialise a <a class="el" href="structcritical__section.html">critical_section</a> structure allowing the system to assign a spin lock number. </p>
 250 <p >The critical section is initialized ready for use, and will use a (possibly shared) spin lock number assigned by the system. Note that in general it is unlikely that you would be nesting critical sections, however if you do so you <em>must</em> use <a class="el" href="group__critical__section.html#gae1b4eb5dcab9ac679970ac43d618de2c">critical_section_init_with_lock_num</a> to ensure that the spin locks used are different.</p>
 251 <dl class="params"><dt>Parameters</dt><dd>
 252   <table class="params">
 253     <tr><td class="paramname">crit_sec</td><td>Pointer to <a class="el" href="structcritical__section.html">critical_section</a> structure </td></tr>
 254   </table>
 255   </dd>
 256 </dl>
 257
 258 </div>
 259 </div>
 260 <a id="gae1b4eb5dcab9ac679970ac43d618de2c" name="gae1b4eb5dcab9ac679970ac43d618de2c"></a>
 261 <h2 class="memtitle"><span class="permalink"><a href="#gae1b4eb5dcab9ac679970ac43d618de2c">&#9670;&nbsp;</a></span>critical_section_init_with_lock_num()</h2>
 262
 263 <div class="memitem">
 264 <div class="memproto">
 265       <table class="memname">
 266         <tr>
 267           <td class="memname">void critical_section_init_with_lock_num </td>
 268           <td>(</td>
 269           <td class="paramtype">critical_section_t *&#160;</td>
 270           <td class="paramname"><em>crit_sec</em>, </td>
 271         </tr>
 272         <tr>
 273           <td class="paramkey"></td>
 274           <td></td>
 275           <td class="paramtype">uint&#160;</td>
 276           <td class="paramname"><em>lock_num</em>&#160;</td>
 277         </tr>
 278         <tr>
 279           <td></td>
 280           <td>)</td>
 281           <td></td><td></td>
 282         </tr>
 283       </table>
 284 </div><div class="memdoc">
 285
 286 <p>Initialise a <a class="el" href="structcritical__section.html">critical_section</a> structure assigning a specific spin lock number. </p>
 287 <dl class="params"><dt>Parameters</dt><dd>
 288   <table class="params">
 289     <tr><td class="paramname">crit_sec</td><td>Pointer to <a class="el" href="structcritical__section.html">critical_section</a> structure </td></tr>
 290     <tr><td class="paramname">lock_num</td><td>the specific spin lock number to use </td></tr>
 291   </table>
 292   </dd>
 293 </dl>
 294
 295 </div>
 296 </div>
 297 </div><!-- contents -->
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