1 | /* |
---|
2 | * Thread Handler |
---|
3 | * |
---|
4 | * |
---|
5 | * COPYRIGHT (c) 1989-1999. |
---|
6 | * On-Line Applications Research Corporation (OAR). |
---|
7 | * |
---|
8 | * The license and distribution terms for this file may be |
---|
9 | * found in found in the file LICENSE in this distribution or at |
---|
10 | * http://www.rtems.com/license/LICENSE. |
---|
11 | * |
---|
12 | * $Id$ |
---|
13 | */ |
---|
14 | |
---|
15 | #if HAVE_CONFIG_H |
---|
16 | #include "config.h" |
---|
17 | #endif |
---|
18 | |
---|
19 | #include <rtems/system.h> |
---|
20 | #include <rtems/score/apiext.h> |
---|
21 | #include <rtems/score/context.h> |
---|
22 | #include <rtems/score/interr.h> |
---|
23 | #include <rtems/score/isr.h> |
---|
24 | #include <rtems/score/object.h> |
---|
25 | #include <rtems/score/priority.h> |
---|
26 | #include <rtems/score/states.h> |
---|
27 | #include <rtems/score/sysstate.h> |
---|
28 | #include <rtems/score/thread.h> |
---|
29 | #include <rtems/score/threadq.h> |
---|
30 | #include <rtems/score/userext.h> |
---|
31 | #include <rtems/score/wkspace.h> |
---|
32 | |
---|
33 | /*PAGE |
---|
34 | * |
---|
35 | * _Thread_Clear_state |
---|
36 | * |
---|
37 | * This kernel routine clears the appropriate states in the |
---|
38 | * requested thread. The thread ready chain is adjusted if |
---|
39 | * necessary and the Heir thread is set accordingly. |
---|
40 | * |
---|
41 | * Input parameters: |
---|
42 | * the_thread - pointer to thread control block |
---|
43 | * state - state set to clear |
---|
44 | * |
---|
45 | * Output parameters: NONE |
---|
46 | * |
---|
47 | * INTERRUPT LATENCY: |
---|
48 | * priority map |
---|
49 | * select heir |
---|
50 | */ |
---|
51 | |
---|
52 | |
---|
53 | void _Thread_Clear_state( |
---|
54 | Thread_Control *the_thread, |
---|
55 | States_Control state |
---|
56 | ) |
---|
57 | { |
---|
58 | ISR_Level level; |
---|
59 | States_Control current_state; |
---|
60 | |
---|
61 | _ISR_Disable( level ); |
---|
62 | current_state = the_thread->current_state; |
---|
63 | |
---|
64 | if ( current_state & state ) { |
---|
65 | current_state = |
---|
66 | the_thread->current_state = _States_Clear( state, current_state ); |
---|
67 | |
---|
68 | if ( _States_Is_ready( current_state ) ) { |
---|
69 | |
---|
70 | _Priority_Add_to_bit_map( &the_thread->Priority_map ); |
---|
71 | |
---|
72 | _Chain_Append_unprotected(the_thread->ready, &the_thread->Object.Node); |
---|
73 | |
---|
74 | _ISR_Flash( level ); |
---|
75 | |
---|
76 | /* |
---|
77 | * If the thread that was unblocked is more important than the heir, |
---|
78 | * then we have a new heir. This may or may not result in a |
---|
79 | * context switch. |
---|
80 | * |
---|
81 | * Normal case: |
---|
82 | * If the current thread is preemptible, then we need to do |
---|
83 | * a context switch. |
---|
84 | * Pseudo-ISR case: |
---|
85 | * Even if the thread isn't preemptible, if the new heir is |
---|
86 | * a pseudo-ISR system task, we need to do a context switch. |
---|
87 | */ |
---|
88 | if ( the_thread->current_priority < _Thread_Heir->current_priority ) { |
---|
89 | _Thread_Heir = the_thread; |
---|
90 | if ( _Thread_Executing->is_preemptible || |
---|
91 | the_thread->current_priority == 0 ) |
---|
92 | _Context_Switch_necessary = true; |
---|
93 | } |
---|
94 | } |
---|
95 | } |
---|
96 | _ISR_Enable( level ); |
---|
97 | } |
---|