osfmk/man/task_set_policy.html

   1 <h2>task_set_policy</h2>
   2 <hr>
   3 <p>
   4 <strong>Function</strong> - Set target task's default scheduling policy state. (Protected Interface.)
   5 <h3>SYNOPSIS</h3>
   6 <pre>
   7 <strong>kern_return_t   task_set_policy</strong>
   8                 <strong>(task_t</strong>                                    <var>task</var>,
   9                  <strong>processor_set_t</strong>                  <var>processor_set</var>,
  10                  <strong>policy_t</strong>                                <var>policy</var>,
  11                  <strong>policy_base_t</strong>                             <var>base</var>,
  12                  <strong>mach_msg_type_number_t</strong>              <var>base_count</var>,
  13                  <strong>policy_limit_t</strong>                           <var>limit</var>,
  14                  <strong>mach_msg_type_number_t</strong>             <var>limit_count</var>,
  15                  <strong>boolean_t</strong>                       <var>change_threads</var><strong>);</strong>
  16 </pre>
  17 <h3>PARAMETERS</h3>
  18 <dl>
  19 <dt> <var>task</var>
  20 <dd>
  21 [in task send right]
  22 The task whose scheduling policy is to be set.
  23 <dt> <var>processor_set</var>
  24 <dd>
  25 [in processor-set-control send right]
  26 The control port for the processor
  27 set to which the task is currently assigned.
  28 <dt> <var>policy</var>
  29 <dd>
  30 [in scalar]
  31 Policy to be set.  The values currently defined are <strong>POLICY_TIMESHARE</strong>,
  32 <strong>POLICY_RR</strong> (round robin) and <strong>POLICY_FIFO</strong> (firstin, first-out).
  33 <dt> <var>base</var>
  34 <dd>
  35 [pointer to in structure]
  36 Base policy specific data, <strong>policy_fifo_base</strong>,
  37 <strong>policy_rr_base</strong> or <strong>policy_timeshare_base</strong>.
  38 <dt> <var>base_count</var>
  39 <dd>
  40 [in scalar]
  41 The size of the buffer (in natural-sized units).
  42 <dt> <var>limit</var>
  43 <dd>
  44 [pointer to in structure]
  45 Policy specific limits, <strong>policy_fifo_limit</strong>,
  46 <strong>policy_rr_limit</strong> or <strong>policy_timeshare_limit</strong>.
  47 <dt> <var>limit_count</var>
  48 <dd>
  49 [in scalar]
  50 The size of the buffer (in natural-sized units).
  51 <dt> <var>change_threads</var>
  52 <dd>
  53 [in scalar]
  54 True if the scheduling attributes for all contained threads
  55 should be changed as well.
  56 </dl>
  57 <h3>DESCRIPTION</h3>
  58 <p>
  59 The <strong>task_set_policy</strong> function sets the scheduling attributes,
  60 both base and limit, for <var>task</var>.
  61 <var>policy</var> may be any policy implemented by the processor set whether or
  62 not it is enabled.
  63 <h3>RETURN VALUES</h3>
  64 <dl>
  65 <dt> <strong>KERN_INVALID_PROCESSOR_SET</strong>
  66 <dd>
  67 <var>processor_set</var> is not the task's processor set control port.
  68 </dl>
  69 <h3>RELATED INFORMATION</h3>
  70 <p>
  71 Functions:
  72 <a href="P_set_policy_control.html"><strong>processor_set_policy_control</strong></a>,
  73 <a href="thread_policy.html"><strong>thread_policy</strong></a>,
  74 <a href="thread_set_policy.html"><strong>thread_set_policy</strong></a>,
  75 <a href="task_policy.html"><strong>task_policy</strong></a>.
  76 <p>
  77 Data Structures:
  78 <a href="policy_fifo_info.html"><strong>policy_fifo_info</strong></a>,
  79 <a href="policy_rr_info.html"><strong>policy_rr_info</strong></a>,
  80 <a href="policy_timeshare_info.html"><strong>policy_timeshare_info</strong></a>.