1<html><head><meta http-equiv="Content-Type" content="text/html; charset=ANSI_X3.4-1968"><title>trace_irq_handler_entry</title><meta name="generator" content="DocBook XSL Stylesheets V1.78.1"><link rel="home" href="index.html" title="The Linux Kernel Tracepoint API"><link rel="up" href="irq.html" title="Chapter&#160;2.&#160;IRQ"><link rel="prev" href="irq.html" title="Chapter&#160;2.&#160;IRQ"><link rel="next" href="API-trace-irq-handler-exit.html" title="trace_irq_handler_exit"></head><body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="3" align="center"><span class="phrase">trace_irq_handler_entry</span></th></tr><tr><td width="20%" align="left"><a accesskey="p" href="irq.html">Prev</a>&#160;</td><th width="60%" align="center">Chapter&#160;2.&#160;IRQ</th><td width="20%" align="right">&#160;<a accesskey="n" href="API-trace-irq-handler-exit.html">Next</a></td></tr></table><hr></div><div class="refentry"><a name="API-trace-irq-handler-entry"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>trace_irq_handler_entry &#8212; 
2  called immediately before the irq action handler
3 </p></div><div class="refsynopsisdiv"><h2>Synopsis</h2><div class="funcsynopsis"><table border="0" class="funcprototype-table" summary="Function synopsis" style="cellspacing: 0; cellpadding: 0;"><tr><td><code class="funcdef">void <b class="fsfunc">trace_irq_handler_entry </b>(</code></td><td>int <var class="pdparam">irq</var>, </td></tr><tr><td>&#160;</td><td>struct irqaction * <var class="pdparam">action</var><code>)</code>;</td></tr></table><div class="funcprototype-spacer">&#160;</div></div></div><div class="refsect1"><a name="idp1117754940"></a><h2>Arguments</h2><div class="variablelist"><dl class="variablelist"><dt><span class="term"><em class="parameter"><code>irq</code></em></span></dt><dd><p>
4     irq number
5    </p></dd><dt><span class="term"><em class="parameter"><code>action</code></em></span></dt><dd><p>
6     pointer to struct irqaction
7    </p></dd></dl></div></div><div class="refsect1"><a name="idp1117557116"></a><h2>Description</h2><p>
8   The struct irqaction pointed to by <em class="parameter"><code>action</code></em> contains various
9   information about the handler, including the device name,
10   <em class="parameter"><code>action</code></em>-&gt;name, and the device id, <em class="parameter"><code>action</code></em>-&gt;dev_id. When used in
11   conjunction with the irq_handler_exit tracepoint, we can figure
12   out irq handler latencies.
13</p></div></div><div class="navfooter"><hr><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="irq.html">Prev</a>&#160;</td><td width="20%" align="center"><a accesskey="u" href="irq.html">Up</a></td><td width="40%" align="right">&#160;<a accesskey="n" href="API-trace-irq-handler-exit.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top">Chapter&#160;2.&#160;IRQ&#160;</td><td width="20%" align="center"><a accesskey="h" href="index.html">Home</a></td><td width="40%" align="right" valign="top">&#160;<span class="phrase">trace_irq_handler_exit</span></td></tr></table></div></body></html>
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