xref: /xnu-10002.41.9/osfmk/man/thread_sample.html (revision 699cd48037512bf4380799317ca44ca453c82f57)
1*699cd480SApple OSS Distributions<h2>thread_sample</h2>
2*699cd480SApple OSS Distributions<hr>
3*699cd480SApple OSS Distributions<p>
4*699cd480SApple OSS Distributions<strong>Function</strong> - Perform periodic PC sampling for a thread.
5*699cd480SApple OSS Distributions<h3>SYNOPSIS</h3>
6*699cd480SApple OSS Distributions<pre>
7*699cd480SApple OSS Distributions<strong>kern_return_t   thread_sample</strong>
8*699cd480SApple OSS Distributions                <strong>(thread_act_t</strong>                     <var>sample_thread</var>,
9*699cd480SApple OSS Distributions                 <strong>mach_port_make_send_t</strong>               <var>reply_port</var><strong>);</strong>
10*699cd480SApple OSS Distributions</pre>
11*699cd480SApple OSS Distributions<h3>PARAMETERS</h3>
12*699cd480SApple OSS Distributions<dl>
13*699cd480SApple OSS Distributions<p>
14*699cd480SApple OSS Distributions<dt> <var>sample_thread</var>
15*699cd480SApple OSS Distributions<dd>
16*699cd480SApple OSS Distributions[in thread send right]
17*699cd480SApple OSS DistributionsThread whose PC is to be sampled
18*699cd480SApple OSS Distributions<p>
19*699cd480SApple OSS Distributions<dt> <var>reply_port</var>
20*699cd480SApple OSS Distributions<dd>
21*699cd480SApple OSS Distributions[in sample receive (to be converted to send) right]
22*699cd480SApple OSS DistributionsPort to which PC
23*699cd480SApple OSS Distributionssample buffers are sent.  A value of <strong>MACH_PORT_NULL</strong> stops PC
24*699cd480SApple OSS Distributionssampling for the thread.
25*699cd480SApple OSS Distributions</dl>
26*699cd480SApple OSS Distributions<h3>DESCRIPTION</h3>
27*699cd480SApple OSS Distributions<p>
28*699cd480SApple OSS DistributionsThe <strong>thread_sample</strong> function causes the program counter
29*699cd480SApple OSS Distributions(PC) of the specified
30*699cd480SApple OSS Distributions<var>sample_thread</var> to be sampled periodically (whenever the thread happens to be
31*699cd480SApple OSS Distributionsrunning at the time of the kernel's "hardclock" interrupt).
32*699cd480SApple OSS DistributionsThe set of PC sample
33*699cd480SApple OSS Distributionsvalues obtained are saved in buffers which are sent to the specified
34*699cd480SApple OSS Distributions<var>reply_port</var> in
35*699cd480SApple OSS Distributions<strong>receive_samples</strong> messages.
36*699cd480SApple OSS Distributions<h3>RETURN VALUES</h3>
37*699cd480SApple OSS Distributions<p>
38*699cd480SApple OSS DistributionsOnly generic errors apply.
39*699cd480SApple OSS Distributions<h3>RELATED INFORMATION</h3>
40*699cd480SApple OSS Distributions<p>
41*699cd480SApple OSS DistributionsFunctions:
42*699cd480SApple OSS Distributions<a href="task_sample.html"><strong>task_sample</strong></a>,
43*699cd480SApple OSS Distributions<a href="receive_samples.html"><strong>receive_samples</strong></a>.
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