xref: /xnu-11215.41.3/osfmk/man/thread_sample.html (revision 33de042d024d46de5ff4e89f2471de6608e37fa4)
1*33de042dSApple OSS Distributions<h2>thread_sample</h2>
2*33de042dSApple OSS Distributions<hr>
3*33de042dSApple OSS Distributions<p>
4*33de042dSApple OSS Distributions<strong>Function</strong> - Perform periodic PC sampling for a thread.
5*33de042dSApple OSS Distributions<h3>SYNOPSIS</h3>
6*33de042dSApple OSS Distributions<pre>
7*33de042dSApple OSS Distributions<strong>kern_return_t   thread_sample</strong>
8*33de042dSApple OSS Distributions                <strong>(thread_act_t</strong>                     <var>sample_thread</var>,
9*33de042dSApple OSS Distributions                 <strong>mach_port_make_send_t</strong>               <var>reply_port</var><strong>);</strong>
10*33de042dSApple OSS Distributions</pre>
11*33de042dSApple OSS Distributions<h3>PARAMETERS</h3>
12*33de042dSApple OSS Distributions<dl>
13*33de042dSApple OSS Distributions<p>
14*33de042dSApple OSS Distributions<dt> <var>sample_thread</var>
15*33de042dSApple OSS Distributions<dd>
16*33de042dSApple OSS Distributions[in thread send right]
17*33de042dSApple OSS DistributionsThread whose PC is to be sampled
18*33de042dSApple OSS Distributions<p>
19*33de042dSApple OSS Distributions<dt> <var>reply_port</var>
20*33de042dSApple OSS Distributions<dd>
21*33de042dSApple OSS Distributions[in sample receive (to be converted to send) right]
22*33de042dSApple OSS DistributionsPort to which PC
23*33de042dSApple OSS Distributionssample buffers are sent.  A value of <strong>MACH_PORT_NULL</strong> stops PC
24*33de042dSApple OSS Distributionssampling for the thread.
25*33de042dSApple OSS Distributions</dl>
26*33de042dSApple OSS Distributions<h3>DESCRIPTION</h3>
27*33de042dSApple OSS Distributions<p>
28*33de042dSApple OSS DistributionsThe <strong>thread_sample</strong> function causes the program counter
29*33de042dSApple OSS Distributions(PC) of the specified
30*33de042dSApple OSS Distributions<var>sample_thread</var> to be sampled periodically (whenever the thread happens to be
31*33de042dSApple OSS Distributionsrunning at the time of the kernel's "hardclock" interrupt).
32*33de042dSApple OSS DistributionsThe set of PC sample
33*33de042dSApple OSS Distributionsvalues obtained are saved in buffers which are sent to the specified
34*33de042dSApple OSS Distributions<var>reply_port</var> in
35*33de042dSApple OSS Distributions<strong>receive_samples</strong> messages.
36*33de042dSApple OSS Distributions<h3>RETURN VALUES</h3>
37*33de042dSApple OSS Distributions<p>
38*33de042dSApple OSS DistributionsOnly generic errors apply.
39*33de042dSApple OSS Distributions<h3>RELATED INFORMATION</h3>
40*33de042dSApple OSS Distributions<p>
41*33de042dSApple OSS DistributionsFunctions:
42*33de042dSApple OSS Distributions<a href="task_sample.html"><strong>task_sample</strong></a>,
43*33de042dSApple OSS Distributions<a href="receive_samples.html"><strong>receive_samples</strong></a>.
44