xref: /xnu-8796.121.2/osfmk/man/thread_sample.html (revision c54f35ca767986246321eb901baf8f5ff7923f6a)
1*c54f35caSApple OSS Distributions<h2>thread_sample</h2>
2*c54f35caSApple OSS Distributions<hr>
3*c54f35caSApple OSS Distributions<p>
4*c54f35caSApple OSS Distributions<strong>Function</strong> - Perform periodic PC sampling for a thread.
5*c54f35caSApple OSS Distributions<h3>SYNOPSIS</h3>
6*c54f35caSApple OSS Distributions<pre>
7*c54f35caSApple OSS Distributions<strong>kern_return_t   thread_sample</strong>
8*c54f35caSApple OSS Distributions                <strong>(thread_act_t</strong>                     <var>sample_thread</var>,
9*c54f35caSApple OSS Distributions                 <strong>mach_port_make_send_t</strong>               <var>reply_port</var><strong>);</strong>
10*c54f35caSApple OSS Distributions</pre>
11*c54f35caSApple OSS Distributions<h3>PARAMETERS</h3>
12*c54f35caSApple OSS Distributions<dl>
13*c54f35caSApple OSS Distributions<p>
14*c54f35caSApple OSS Distributions<dt> <var>sample_thread</var>
15*c54f35caSApple OSS Distributions<dd>
16*c54f35caSApple OSS Distributions[in thread send right]
17*c54f35caSApple OSS DistributionsThread whose PC is to be sampled
18*c54f35caSApple OSS Distributions<p>
19*c54f35caSApple OSS Distributions<dt> <var>reply_port</var>
20*c54f35caSApple OSS Distributions<dd>
21*c54f35caSApple OSS Distributions[in sample receive (to be converted to send) right]
22*c54f35caSApple OSS DistributionsPort to which PC
23*c54f35caSApple OSS Distributionssample buffers are sent.  A value of <strong>MACH_PORT_NULL</strong> stops PC
24*c54f35caSApple OSS Distributionssampling for the thread.
25*c54f35caSApple OSS Distributions</dl>
26*c54f35caSApple OSS Distributions<h3>DESCRIPTION</h3>
27*c54f35caSApple OSS Distributions<p>
28*c54f35caSApple OSS DistributionsThe <strong>thread_sample</strong> function causes the program counter
29*c54f35caSApple OSS Distributions(PC) of the specified
30*c54f35caSApple OSS Distributions<var>sample_thread</var> to be sampled periodically (whenever the thread happens to be
31*c54f35caSApple OSS Distributionsrunning at the time of the kernel's "hardclock" interrupt).
32*c54f35caSApple OSS DistributionsThe set of PC sample
33*c54f35caSApple OSS Distributionsvalues obtained are saved in buffers which are sent to the specified
34*c54f35caSApple OSS Distributions<var>reply_port</var> in
35*c54f35caSApple OSS Distributions<strong>receive_samples</strong> messages.
36*c54f35caSApple OSS Distributions<h3>RETURN VALUES</h3>
37*c54f35caSApple OSS Distributions<p>
38*c54f35caSApple OSS DistributionsOnly generic errors apply.
39*c54f35caSApple OSS Distributions<h3>RELATED INFORMATION</h3>
40*c54f35caSApple OSS Distributions<p>
41*c54f35caSApple OSS DistributionsFunctions:
42*c54f35caSApple OSS Distributions<a href="task_sample.html"><strong>task_sample</strong></a>,
43*c54f35caSApple OSS Distributions<a href="receive_samples.html"><strong>receive_samples</strong></a>.
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