osfmk/man/thread_policy.html

   1 <h2>thread_policy</h2>
   2 <hr>
   3 <p>
   4 <strong>Function</strong> - Set target thread's scheduling policy state.
   5 <h3>SYNOPSIS</h3>
   6 <pre>
   7 <strong>kern_return_t   thread_policy</strong>
   8                 <strong>(thread_act_t</strong>                            <var>thread</var>,
   9                  <strong>policy_t</strong>                                <var>policy</var>,
  10                  <strong>policy_base_t</strong>                             <var>base</var>,
  11                  <strong>base</strong>                                <var>base_count</var>,
  12                  <strong>boolean_t</strong>                            <var>set_limit</var><strong>);</strong>
  13 </pre>
  14 <h3>PARAMETERS</h3>
  15 <dl>
  16 <p>
  17 <dt> <var>thread</var>
  18 <dd>
  19 [in thread send right]
  20 The thread scheduling policy is to be set.
  21 <p>
  22 <dt> <var>policy</var>
  23 <dd>
  24 [in scalar]
  25 Policy to be set.  The values currently defined are <strong>POLICY_TIMESHARE</strong>,
  26 <strong>POLICY_RR</strong> (round robin) and <strong>POLICY_FIFO</strong> (firstin, first-out).
  27 <p>
  28 <dt> <var>base</var>
  29 <dd>
  30 [pointer to in structure]
  31 Base scheduling policy specific data,
  32 <strong>policy_fifo_base</strong>, <strong>policy_rr_base</strong> or <strong>policy_timeshare_base</strong>.
  33 <p>
  34 <dt> <var>base_count</var>
  35 <dd>
  36 [in scalar]
  37 The size of the buffer (in natural-sized units).
  38 <p>
  39 <dt> <var>set_limit</var>
  40 <dd>
  41 [in scalar]
  42 True if the thread's scheduling limits should be restricted to
  43 allow no more service than specified by <var>base</var>.
  44 </dl>
  45 <h3>DESCRIPTION</h3>
  46 <p>
  47 The <strong>thread_policy</strong> function sets the scheduling policy
  48 to be applied to thread.  <var>policy</var> must be a scheduling policy
  49 currently "enabled" for the thread's assigned processor set.
  50 <h3>RETURN VALUES</h3>
  51 <dl>
  52 <p>
  53 <dt> <strong>KERN_INVALID_POLICY</strong>
  54 <dd>
  55 The processor set to which <var>thread</var> is currently assigned does
  56 not currently enable <var>policy</var>.
  57 <p>
  58 <dt> <strong>KERN_POLICY_LIMIT</strong>
  59 <dd>
  60 The specified scheduling attributes exceeds the thread's limits.
  61 </dl>
  62 <h3>RELATED INFORMATION</h3>
  63 <p>
  64 Functions:
  65 <a href="P_set_policy_control.html"><strong>processor_set_policy_control</strong></a>,
  66 <a href="thread_set_policy.html"><strong>thread_set_policy</strong></a>,
  67 <a href="task_policy.html"><strong>task_policy</strong></a>,
  68 <a href="task_set_policy.html"><strong>task_set_policy</strong></a>.
  69 <p>
  70 Data Structures:
  71 <a href="policy_fifo_info.html"><strong>policy_fifo_info</strong></a>,
  72 <a href="policy_rr_info.html"><strong>policy_rr_info</strong></a>,
  73 <a href="policy_timeshare_info.html"><strong>policy_timeshare_info</strong></a>.