source: rtems/cpukit/posix/include/rtems/posix/priority.h @ 6881e0c

4.104.114.84.95
Last change on this file since 6881e0c was 6881e0c, checked in by Joel Sherrill <joel.sherrill@…>, on 04/15/97 at 18:02:18

Reduced number of POSIX thread priorities from 255 to 254 to avoid conflicts
of lowest priority with the RTEMS IDLE thread. This was causing the lowest
priority GNAT Ada task to never run.

  • Property mode set to 100644
File size: 1.0 KB
Line 
1/*
2 *
3 *
4 *  $Id$
5 */
6
7#ifndef __RTEMS_POSIX_PRIORITY_h
8#define __RTEMS_POSIX_PRIORITY_h
9
10#include <rtems/score/priority.h>
11
12/*
13 *  1003.1b-1993,2.2.2.80 definition of priority, p. 19
14 *
15 *  "Numericallly higher values represent higher priorities."
16 *
17 *  Thus, RTEMS Core has priorities run in the opposite sense of the POSIX API.
18 *
19 *  There are only 254 posix priority levels since a task at priority level
20 *  255 would never run because of the RTEMS idle task.  This is necessary
21 *  because GNAT maps the lowest Ada task priority to the lowest thread
22 *  priority.  The lowest priority Ada task should get to run, so there is
23 *  a fundamental conflict with having 255 priorities.
24 */
25
26#define POSIX_SCHEDULER_MAXIMUM_PRIORITY (254)
27 
28#define POSIX_SCHEDULER_MINIMUM_PRIORITY (1)
29
30RTEMS_INLINE_ROUTINE boolean _POSIX_Priority_Is_valid(
31  int priority
32);
33
34RTEMS_INLINE_ROUTINE Priority_Control _POSIX_Priority_To_core(
35  int priority
36);
37
38RTEMS_INLINE_ROUTINE int _POSIX_Priority_From_core(
39  Priority_Control priority
40);
41
42#include <rtems/posix/priority.inl>
43
44#endif
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