1<html><head><meta http-equiv="Content-Type" content="text/html; charset=ANSI_X3.4-1968"><title>yield</title><meta name="generator" content="DocBook XSL Stylesheets V1.78.1"><link rel="home" href="index.html" title="Linux Device Drivers"><link rel="up" href="ch01s03.html" title="Delaying, scheduling, and timer routines"><link rel="prev" href="API-sched-setscheduler.html" title="sched_setscheduler"><link rel="next" href="API-yield-to.html" title="yield_to"></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">yield</span></th></tr><tr><td width="20%" align="left"><a accesskey="p" href="API-sched-setscheduler.html">Prev</a>&#160;</td><th width="60%" align="center">Delaying, scheduling, and timer routines</th><td width="20%" align="right">&#160;<a accesskey="n" href="API-yield-to.html">Next</a></td></tr></table><hr></div><div class="refentry"><a name="API-yield"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>yield &#8212; 
2     yield the current processor to other threads.
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 __sched <b class="fsfunc">yield </b>(</code></td><td> <var class="pdparam">void</var><code>)</code>;</td></tr></table><div class="funcprototype-spacer">&#160;</div></div></div><div class="refsect1"><a name="idp1106779764"></a><h2>Arguments</h2><div class="variablelist"><dl class="variablelist"><dt><span class="term"><em class="parameter"><code>void</code></em></span></dt><dd><p>
4     no arguments
5    </p></dd></dl></div></div><div class="refsect1"><a name="idp1106781292"></a><h2>Description</h2><p>
6   </p><p>
7
8   Do not ever use this function, there's a 99% chance you're doing it wrong.
9   </p><p>
10
11   The scheduler is at all times free to pick the calling task as the most
12   eligible task to run, if removing the <code class="function">yield</code> call from your code breaks
13   it, its already broken.
14</p></div><div class="refsect1"><a name="idp1106782716"></a><h2>Typical broken usage is</h2><p>
15   </p><p>
16
17   while (!event)
18   <code class="function">yield</code>;
19   </p><p>
20
21   where one assumes that <code class="function">yield</code> will let 'the other' process run that will
22   make event true. If the current task is a SCHED_FIFO task that will never
23   happen. Never use <code class="function">yield</code> as a progress guarantee!!
24   </p><p>
25
26   If you want to use <code class="function">yield</code> to wait for something, use <code class="function">wait_event</code>.
27   If you want to use <code class="function">yield</code> to be 'nice' for others, use <code class="function">cond_resched</code>.
28   If you still want to use <code class="function">yield</code>, do not!
29</p></div></div><div class="navfooter"><hr><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="API-sched-setscheduler.html">Prev</a>&#160;</td><td width="20%" align="center"><a accesskey="u" href="ch01s03.html">Up</a></td><td width="40%" align="right">&#160;<a accesskey="n" href="API-yield-to.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top"><span class="phrase">sched_setscheduler</span>&#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">yield_to</span></td></tr></table></div></body></html>
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