xnu-2422.1.72.tar.gz

[apple/xnu.git] / osfmk / man / thread_wire.html

<h2>thread_wire</h2>
<hr>
<p>
<strong>Function</strong> - Mark the thread as privileged with respect to kernel resources.
<h3>SYNOPSIS</h3>
<pre>
<strong>kern_return_t   thread_wire</strong>
                <strong>(host_priv_t</strong>                          <var>host_priv</var>,
                 <strong>thread_act_t</strong>                            <var>thread</var>,
                 <strong>boolean_t</strong>                                <var>wired</var><strong>);</strong>
</pre>
<h3>PARAMETERS</h3>
<dl>
<p>
<dt> <var>host_priv</var> 
<dd>
[in host-control send right]
The privileged control port for the host on 
which the thread executes.
<p>
<dt> <var>thread</var> 
<dd>
[in thread send right]
The thread to be wired.
<p>
<dt> <var>wired</var> 
<dd>
[in scalar]
<strong>TRUE</strong> if the thread is to be wired.
</dl>
<h3>DESCRIPTION</h3>
<p>
The <strong>thread_wire</strong> function marks the thread as "wired".
A "wired" thread is
always eligible to be scheduled and can consume physical memory even when 
free memory is scarce.  This property should be assigned to threads in the
default page-out path.  Threads not in the default page-out path
should not have 
this property to prevent the kernel's free list of pages from being exhausted.
<h3>RETURN VALUES</h3>
<dl>
<p>
<dt> <strong>KERN_INVALID_ARGUMENT</strong>
<dd>
<var>thread</var> is not a thread port.
.P
<var>host_priv</var> is not the control port for the host on which <var>thread</var>
executes.
</dl>
<h3>RELATED INFORMATION</h3>
<p>
Functions:
<a href="vm_wire.html"><strong>vm_wire</strong></a>.