summaryrefslogtreecommitdiffstats
path: root/cpukit/include/rtems/score/schedulerpriorityimpl.h
blob: bf1d411502e01cc14c9772da547e671d0beb847f (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
/**
 * @file
 *
 * @brief Inlined Routines Associated with the Manipulation of the
 * Priority-Based Scheduling Structures
 *
 * This inline file contains all of the inlined routines associated with
 * the manipulation of the priority-based scheduling structures.
 */

/*
 *  Copyright (C) 2010 Gedare Bloom.
 *  Copyright (C) 2011 On-Line Applications Research Corporation (OAR).
 *
 *  The license and distribution terms for this file may be
 *  found in the file LICENSE in this distribution or at
 *  http://www.rtems.org/license/LICENSE.
 */

#ifndef _RTEMS_SCORE_SCHEDULERPRIORITYIMPL_H
#define _RTEMS_SCORE_SCHEDULERPRIORITYIMPL_H

#include <rtems/score/schedulerpriority.h>
#include <rtems/score/chainimpl.h>
#include <rtems/score/prioritybitmapimpl.h>
#include <rtems/score/schedulerimpl.h>
#include <rtems/score/thread.h>

#ifdef __cplusplus
extern "C" {
#endif

/**
 * @addtogroup RTEMSScoreSchedulerDPS
 */
/**@{**/

RTEMS_INLINE_ROUTINE Scheduler_priority_Context *
  _Scheduler_priority_Get_context( const Scheduler_Control *scheduler )
{
  return (Scheduler_priority_Context *) _Scheduler_Get_context( scheduler );
}

RTEMS_INLINE_ROUTINE Scheduler_priority_Node *_Scheduler_priority_Thread_get_node(
  Thread_Control *the_thread
)
{
  return (Scheduler_priority_Node *) _Thread_Scheduler_get_home_node( the_thread );
}

RTEMS_INLINE_ROUTINE Scheduler_priority_Node *_Scheduler_priority_Node_downcast(
  Scheduler_Node *node
)
{
  return (Scheduler_priority_Node *) node;
}

/**
 * @brief Ready queue initialization.
 *
 * This routine initializes @a ready_queues for priority-based scheduling.
 */
RTEMS_INLINE_ROUTINE void _Scheduler_priority_Ready_queue_initialize(
  Chain_Control    *ready_queues,
  Priority_Control  maximum_priority
)
{
  size_t index;

  for ( index = 0 ; index <= (size_t) maximum_priority ; ++index ) {
    _Chain_Initialize_empty( &ready_queues[ index ] );
  }
}

/**
 * @brief Enqueues a node on the specified ready queue.
 *
 * The node is placed as the last element of its priority group.
 *
 * @param[in] node The node to enqueue.
 * @param[in] ready_queue The ready queue.
 * @param[in] bit_map The priority bit map of the scheduler instance.
 */
RTEMS_INLINE_ROUTINE void _Scheduler_priority_Ready_queue_enqueue(
  Chain_Node                     *node,
  Scheduler_priority_Ready_queue *ready_queue,
  Priority_bit_map_Control       *bit_map
)
{
  Chain_Control *ready_chain = ready_queue->ready_chain;

  _Chain_Append_unprotected( ready_chain, node );
  _Priority_bit_map_Add( bit_map, &ready_queue->Priority_map );
}

/**
 * @brief Enqueues a node on the specified ready queue as first.
 *
 * The node is placed as the first element of its priority group.
 *
 * @param[in] node The node to enqueue as first.
 * @param[in] ready_queue The ready queue.
 * @param[in] bit_map The priority bit map of the scheduler instance.
 */
RTEMS_INLINE_ROUTINE void _Scheduler_priority_Ready_queue_enqueue_first(
  Chain_Node                     *node,
  Scheduler_priority_Ready_queue *ready_queue,
  Priority_bit_map_Control       *bit_map
)
{
  Chain_Control *ready_chain = ready_queue->ready_chain;

  _Chain_Prepend_unprotected( ready_chain, node );
  _Priority_bit_map_Add( bit_map, &ready_queue->Priority_map );
}

/**
 * @brief Extracts a node from the specified ready queue.
 *
 * @param[in] node The node to extract.
 * @param[in] ready_queue The ready queue.
 * @param[in] bit_map The priority bit map of the scheduler instance.
 */
RTEMS_INLINE_ROUTINE void _Scheduler_priority_Ready_queue_extract(
  Chain_Node                     *node,
  Scheduler_priority_Ready_queue *ready_queue,
  Priority_bit_map_Control       *bit_map
)
{
  Chain_Control *ready_chain = ready_queue->ready_chain;

  if ( _Chain_Has_only_one_node( ready_chain ) ) {
    _Chain_Initialize_empty( ready_chain );
    _Chain_Initialize_node( node );
    _Priority_bit_map_Remove( bit_map, &ready_queue->Priority_map );
  } else {
    _Chain_Extract_unprotected( node );
  }
}

RTEMS_INLINE_ROUTINE void _Scheduler_priority_Extract_body(
  const Scheduler_Control *scheduler,
  Thread_Control          *the_thread,
  Scheduler_Node          *node
)
{
  Scheduler_priority_Context *context;
  Scheduler_priority_Node    *the_node;

  context = _Scheduler_priority_Get_context( scheduler );
  the_node = _Scheduler_priority_Node_downcast( node );

  _Scheduler_priority_Ready_queue_extract(
    &the_thread->Object.Node,
    &the_node->Ready_queue,
    &context->Bit_map
  );
}

/**
 * @brief Return a pointer to the first node.
 *
 * This routines returns a pointer to the first node on @a ready_queues.
 *
 * @param[in] bit_map The priority bit map of the scheduler instance.
 * @param[in] ready_queues The ready queues of the scheduler instance.
 *
 * @return This method returns the first node.
 */
RTEMS_INLINE_ROUTINE Chain_Node *_Scheduler_priority_Ready_queue_first(
  Priority_bit_map_Control *bit_map,
  Chain_Control            *ready_queues
)
{
  Priority_Control index = _Priority_bit_map_Get_highest( bit_map );
  Chain_Node *first = _Chain_First( &ready_queues[ index ] );

  _Assert( first != _Chain_Tail( &ready_queues[ index ] ) );

  return first;
}

/**
 * @brief Scheduling decision logic.
 *
 * This kernel routine implements scheduling decision logic
 * for priority-based scheduling.
 */
RTEMS_INLINE_ROUTINE void _Scheduler_priority_Schedule_body(
  const Scheduler_Control *scheduler,
  Thread_Control          *the_thread,
  bool                     force_dispatch
)
{
  Scheduler_priority_Context *context =
    _Scheduler_priority_Get_context( scheduler );
  Thread_Control *heir = (Thread_Control *)
    _Scheduler_priority_Ready_queue_first(
      &context->Bit_map,
      &context->Ready[ 0 ]
    );

  ( void ) the_thread;

  _Scheduler_Update_heir( heir, force_dispatch );
}

/**
 * @brief Updates the specified ready queue data according to the new priority
 * value.
 *
 * @param[in] ready_queue The ready queue.
 * @param[in] new_priority The new priority.
 * @param[in] bit_map The priority bit map of the scheduler instance.
 * @param[in] ready_queues The ready queues of the scheduler instance.
 */
RTEMS_INLINE_ROUTINE void _Scheduler_priority_Ready_queue_update(
  Scheduler_priority_Ready_queue *ready_queue,
  unsigned int                    new_priority,
  Priority_bit_map_Control       *bit_map,
  Chain_Control                  *ready_queues
)
{
  ready_queue->current_priority = new_priority;
  ready_queue->ready_chain = &ready_queues[ new_priority ];

  _Priority_bit_map_Initialize_information(
    bit_map,
    &ready_queue->Priority_map,
    new_priority
  );
}

/** @} */

#ifdef __cplusplus
}
#endif

#endif
/* end of include file */