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1 <h2>policy_fifo_info</h2>
2 <hr>
3 <p>
4 <strong>Structure</strong> - Specifies information associated with the system's First-In-First-Out scheduling policy.
5 <h3>SYNOPSIS</h3>
6 <pre>
7 <strong>struct policy_fifo_limit</strong>
8 <strong>{</strong>
9 <strong>int</strong> <var>max_priority</var><strong>;</strong>
10 <strong>};</strong>
11
12 <strong>struct policy_fifo_base</strong>
13 <strong>{</strong>
14 <strong>int</strong> <var>base_priority</var><strong>;</strong>
15 <strong>};</strong>
16
17 <strong>struct policy_fifo_info</strong>
18 <strong>{</strong>
19 <strong>int</strong> <var>max_priority</var><strong>;</strong>
20 <strong>int</strong> <var>base_priority</var><strong>;</strong>
21 <strong>boolean_t</strong> <var>depressed</var><strong>;</strong>
22 <strong>int</strong> <var>depress_priority</var><strong>;</strong>
23 <strong>};</strong>
24 </pre>
25 <h3>FIELDS</h3>
26 <dl>
27 <dt> <var>max_priority</var>
28 <dd>
29 Maximum scheduling priority
30 <p>
31 <dt> <var>base_priority</var>
32 <dd>
33 Scheduling priority
34 <p>
35 <dt> <var>depressed</var>
36 <dd>
37 True if scheduling priority is depressed
38 <p>
39 <dt> <var>depress_priority</var>
40 <dd>
41 Scheduling priority from which depressed
42 </dl>
43 <h3>DESCRIPTION</h3>
44 <p>
45 The <strong>policy_fifo_info</strong> structure defines the first-in-first-out
46 scheduling policy information.
47 FIFO threads have two priorities associated with them by the system:
48 <ul>
49 <p>
50 <li>
51 A maximum priority value which can be raised only via privileged operation
52 so that users may not unfairly compete with other users in their processor
53 set. Newly created threads obtain their maximum priority from that of their
54 assigned processor set.
55 <p>
56 <li>
57 A priority value which can be set by the thread to any value up to a
58 maximum priority. Newly created threads obtain their priority from their task.
59 </ul>
60 <h3>RELATED INFORMATION</h3>
61 <p>
62 Functions:
63 <a href="thread_info.html"><strong>thread_info</strong></a>,
64 <a href="task_info.html"><strong>task_info</strong></a>,
65 <a href="processor_set_info.html"><strong>processor_set_info</strong></a>,
66 <a href="P_set_policy_control.html"><strong>processor_set_policy_control</strong></a>,
67 <a href="P_set_policy_disable.html"><strong>processor_set_policy_disable</strong></a>,
68 <a href="P_set_policy_enable.html"><strong>processor_set_policy_enable</strong></a>,
69 <a href="task_policy.html"><strong>task_policy</strong></a>,
70 <a href="thread_policy.html"><strong>thread_policy</strong></a>,
71 <a href="thread_set_policy.html"><strong>thread_set_policy</strong></a>.
72 <p>
73 Data Structures:
74 <a href="policy_rr_info.html"><strong>policy_rr_info</strong></a>,
75 <a href="policy_timeshare_info.html"><strong>policy_timeshare_info</strong></a>.