osfmk/man/processor_set_max_priority.html

   1 <h2>processor_set_max_priority</h2>
   2 <hr>
   3 <p>
   4 <strong>Function</strong> - Sets the maximum scheduling priority for a processor set.
   5 <h3>SYNOPSIS</h3>
   6 <pre>
   7 <strong>#include&lt mach/mach_host.h&gt</strong>
   8
   9 <strong>kern_return_t   processor_set_max_priority</strong>
  10                 <strong>(processor_set_t</strong>       <var>processor_set</var>,
  11                 <strong>int</strong>    <var>priority</var>,
  12                 <strong>boolean_t</strong>      <var>change_threads</var><strong>);</strong>
  13 </pre>
  14 <h3>PARAMETERS</h3>
  15 <dl>
  16 <dt> <var>processor_set</var>
  17 <dd>
  18 [in processor-set-control port] The control port for the processor set whose maximum scheduling priority is to be set.
  19 <dt> <var>priority</var>
  20 <dd>
  21 [in scalar] The new priority for the processor set.
  22 <dt> <var>change_threads</var>
  23 <dd>
  24 [in scalar] True if the maximum priority of existing threads assigned to this processor set should also be changed.
  25 </dl>
  26 <h3>DESCRIPTION</h3>
  27 <p>
  28 The <strong>processor_set_max_priority</strong>
  29 function sets the maximum scheduling <var>priority</var> for
  30 <var>processor_set</var>. The maximum <var>priority</var> of a
  31 processor set is used only when creating new threads. A new thread's
  32 maximum <var>priority</var> is set to that of its assigned processor
  33 set. When assigned to a processor set, a thread's maximum
  34 <var>priority</var> is reduced, if necessary, to that of its new
  35 processor set; its current <var>priority</var> is also reduced, as
  36 needed. Changing the maximum <var>priority</var> of a processor set
  37 does not affect the <var>priority</var> of the currently assigned
  38 threads unless <var>change_threads</var> is TRUE. If this
  39 <var>priority</var> change violates the maximum <var>priority</var> of
  40 some threads, their maximum priorities will be reduced to match.
  41 <h3>RETURN VALUES</h3>
  42 <p>
  43 Only generic errors apply.
  44 <h3>RELATED INFORMATION</h3>
  45 <p>
  46 Functions:
  47 <a href="thread_assign.html">thread_assign</a>.