summaryrefslogtreecommitdiffstats
path: root/c/src/exec/rtems/src/ratemon.c
blob: c98de762af887fe4a41012201a58a3cca53eb345 (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
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
/*
 *  Rate Monotonic Manager
 *
 *
 *  COPYRIGHT (c) 1989, 1990, 1991, 1992, 1993, 1994.
 *  On-Line Applications Research Corporation (OAR).
 *  All rights assigned to U.S. Government, 1994.
 *
 *  This material may be reproduced by or for the U.S. Government pursuant
 *  to the copyright license under the clause at DFARS 252.227-7013.  This
 *  notice must appear in all copies of this file and its derivatives.
 *
 *  $Id$
 */

#include <rtems/system.h>
#include <rtems/support.h>
#include <rtems/isr.h>
#include <rtems/object.h>
#include <rtems/ratemon.h>
#include <rtems/thread.h>

/*PAGE
 *
 *  _Rate_monotonic_Manager_initialization
 *
 *  This routine initializes all Rate Monotonic Manager related
 *  data structures.
 *
 *  Input parameters:
 *    maximum_periods - number of periods timers to initialize
 *
 *  Output parameters:  NONE
 *
 *  NOTE: The Rate Monotonic Manager is built on top of the Watchdog
 *        Handler.
 */

void _Rate_monotonic_Manager_initialization(
  unsigned32 maximum_periods
)
{
  _Objects_Initialize_information(
    &_Rate_monotonic_Information,
    OBJECTS_RTEMS_PERIODS,
    FALSE,
    maximum_periods,
    sizeof( Rate_monotonic_Control ),
    FALSE,
    RTEMS_MAXIMUM_NAME_LENGTH,
    FALSE
  );
}

/*PAGE
 *
 *  rtems_rate_monotonic_create
 *
 *  This directive creates a rate monotonic timer and performs
 *  some initialization.
 *
 *  Input parameters:
 *    name - name of period
 *    id   - pointer to rate monotonic id
 *
 *  Output parameters:
 *    id                - rate monotonic id
 *    RTEMS_SUCCESSFUL - if successful
 *    error code        - if unsuccessful
 */

rtems_status_code rtems_rate_monotonic_create(
  rtems_name    name,
  Objects_Id   *id
)
{
  Rate_monotonic_Control *the_period;

  if ( !rtems_is_name_valid( name ) )
    return( RTEMS_INVALID_NAME );

  _Thread_Disable_dispatch();            /* to prevent deletion */

  the_period = _Rate_monotonic_Allocate();

  if ( !the_period ) {
    _Thread_Enable_dispatch();
    return( RTEMS_TOO_MANY );
  }

  the_period->owner = _Thread_Executing;
  the_period->state = RATE_MONOTONIC_INACTIVE;

  _Objects_Open( &_Rate_monotonic_Information, &the_period->Object, &name );

  *id = the_period->Object.id;
  _Thread_Enable_dispatch();
  return( RTEMS_SUCCESSFUL );
}

/*PAGE
 *
 *  rtems_rate_monotonic_ident
 *
 *  This directive returns the system ID associated with
 *  the rate monotonic period name.
 *
 *  Input parameters:
 *    name - user defined period name
 *    id   - pointer to period id
 *
 *  Output parameters:
 *    *id               - region id
 *    RTEMS_SUCCESSFUL - if successful
 *    error code        - if unsuccessful
 */

rtems_status_code rtems_rate_monotonic_ident(
  rtems_name    name,
  Objects_Id   *id
)
{
  return _Objects_Name_to_id(
    &_Rate_monotonic_Information,
    &name,
    RTEMS_SEARCH_LOCAL_NODE,
    id
  );
}

/*PAGE
 *
 *  rtems_rate_monotonic_cancel
 *
 *  This directive allows a thread to cancel a rate monotonic timer.
 *
 *  Input parameters:
 *    id - rate monotonic id
 *
 *  Output parameters:
 *    RTEMS_SUCCESSFUL - if successful and caller is not the owning thread
 *    error code        - if unsuccessful
 */

rtems_status_code rtems_rate_monotonic_cancel(
  Objects_Id id
)
{
  Rate_monotonic_Control *the_period;
  Objects_Locations              location;

  the_period = _Rate_monotonic_Get( id, &location );
  switch ( location ) {
    case OBJECTS_ERROR:
      return( RTEMS_INVALID_ID );
    case OBJECTS_REMOTE:            /* should never return this */
      return( RTEMS_INTERNAL_ERROR );
    case OBJECTS_LOCAL:
      if ( !_Thread_Is_executing( the_period->owner ) ) {
        _Thread_Enable_dispatch();
        return( RTEMS_NOT_OWNER_OF_RESOURCE );
      }
      (void) _Watchdog_Remove( &the_period->Timer );
      the_period->state = RATE_MONOTONIC_INACTIVE;
      _Thread_Enable_dispatch();
      return( RTEMS_SUCCESSFUL );
  }

  return( RTEMS_INTERNAL_ERROR );   /* unreached - only to remove warnings */
}

/*PAGE
 *
 *  rtems_rate_monotonic_delete
 *
 *  This directive allows a thread to delete a rate monotonic timer.
 *
 *  Input parameters:
 *    id - rate monotonic id
 *
 *  Output parameters:
 *    RTEMS_SUCCESSFUL - if successful
 *    error code        - if unsuccessful
 */

rtems_status_code rtems_rate_monotonic_delete(
  Objects_Id id
)
{
  Rate_monotonic_Control *the_period;
  Objects_Locations              location;

  the_period = _Rate_monotonic_Get( id, &location );
  switch ( location ) {
    case OBJECTS_ERROR:
      return( RTEMS_INVALID_ID );
    case OBJECTS_REMOTE:            /* should never return this */
      return( RTEMS_INTERNAL_ERROR );
    case OBJECTS_LOCAL:
      _Objects_Close( &_Rate_monotonic_Information, &the_period->Object );
      (void) _Watchdog_Remove( &the_period->Timer );
      the_period->state = RATE_MONOTONIC_INACTIVE;
      _Rate_monotonic_Free( the_period );
      _Thread_Enable_dispatch();
      return( RTEMS_SUCCESSFUL );
  }

  return( RTEMS_INTERNAL_ERROR );   /* unreached - only to remove warnings */
}

/*PAGE
 *
 *  rtems_rate_monotonic_period
 *
 *  This directive allows a thread to manipulate a rate monotonic timer.
 *
 *  Input parameters:
 *    id     - rate monotonic id
 *    length - length of period (in ticks)
 *
 *  Output parameters:
 *    RTEMS_SUCCESSFUL - if successful
 *    error code        - if unsuccessful
 */

rtems_status_code rtems_rate_monotonic_period(
  Objects_Id        id,
  rtems_interval length
)
{
  Rate_monotonic_Control *the_period;
  Objects_Locations       location;
  rtems_status_code            return_value;

  the_period = _Rate_monotonic_Get( id, &location );
  switch ( location ) {
    case OBJECTS_ERROR:
      return( RTEMS_INVALID_ID );
    case OBJECTS_REMOTE:            /* should never return this */
      return( RTEMS_INTERNAL_ERROR );
    case OBJECTS_LOCAL:
      if ( !_Thread_Is_executing( the_period->owner ) ) {
        _Thread_Enable_dispatch();
        return( RTEMS_NOT_OWNER_OF_RESOURCE );
      }

      if ( length == RTEMS_PERIOD_STATUS ) {
        switch ( the_period->state ) {
          case RATE_MONOTONIC_INACTIVE:
            return_value = RTEMS_NOT_DEFINED;
            break;
          case RATE_MONOTONIC_ACTIVE:
            return_value = RTEMS_SUCCESSFUL;
            break;
          case RATE_MONOTONIC_EXPIRED:
            return_value = RTEMS_TIMEOUT;
            break;
          default:              /* unreached -- only to remove warnings */
            return_value = RTEMS_INTERNAL_ERROR;
            break;
        }
        _Thread_Enable_dispatch();
        return( return_value );
      }

      switch ( the_period->state ) {
        case RATE_MONOTONIC_INACTIVE:
          the_period->state = RATE_MONOTONIC_ACTIVE;
          _Watchdog_Initialize(
            &the_period->Timer,
            _Rate_monotonic_Timeout,
            id,
            NULL
          );
          _Watchdog_Insert_ticks(
                     &the_period->Timer, length, WATCHDOG_ACTIVATE_NOW );
          _Thread_Enable_dispatch();
          return( RTEMS_SUCCESSFUL );

        case RATE_MONOTONIC_ACTIVE:
/* following is and could be a critical section problem */
          _Thread_Executing->Wait.id  = the_period->Object.id;
          if ( _Rate_monotonic_Set_state( the_period ) ) {
            _Thread_Enable_dispatch();
            return( RTEMS_SUCCESSFUL );
          }
         /* has expired -- fall into next case */
        case RATE_MONOTONIC_EXPIRED:
          the_period->state = RATE_MONOTONIC_ACTIVE;
          _Watchdog_Insert_ticks(
                     &the_period->Timer, length, WATCHDOG_ACTIVATE_NOW );
          _Thread_Enable_dispatch();
          return( RTEMS_TIMEOUT );
      }
  }

  return( RTEMS_INTERNAL_ERROR );   /* unreached - only to remove warnings */
}

/*PAGE
 *
 * _Rate_monotonic_Set_state
 *
 * This kernel routine sets the STATES_WAITING_FOR_PERIOD state in
 * the running thread's tcb if the specified period has not expired.
 * The ready chain is adjusted if necessary.
 *
 * Input parameters:
 *   the_period - pointer to period control block
 *
 * Output parameters:
 *   TRUE  - if blocked successfully for period
 *   FALSE - if period has expired
 *
 *  INTERRUPT LATENCY:
 *    delete node
 *    priority map
 *    select heir
 */

boolean _Rate_monotonic_Set_state(
Rate_monotonic_Control *the_period
)
{
  Thread_Control *executing;
  Chain_Control  *ready;
  ISR_Level              level;
  States_Control         old_state;

  executing = _Thread_Executing;
  ready     = executing->ready;
  _ISR_Disable( level );

  old_state = executing->current_state;

  if ( _Rate_monotonic_Is_expired( the_period ) ) {
    _ISR_Enable( level );
    return( FALSE );
  }

  executing->current_state =
             _States_Set( STATES_WAITING_FOR_PERIOD, old_state );

  if ( _States_Is_ready( old_state ) ) {
    if ( _Chain_Has_only_one_node( ready ) ) {
      _Chain_Initialize_empty( ready );
      _Priority_Remove_from_bit_map( &executing->Priority_map );
      _ISR_Flash( level );
    } else {
      _Chain_Extract_unprotected( &executing->Object.Node );
      _ISR_Flash( level );
    }

    if ( _Thread_Is_heir( executing ) )
      _Thread_Calculate_heir();

    _Context_Switch_necessary = TRUE;
  }

  _ISR_Enable( level );
  return( TRUE );
}

/*PAGE
 *
 *  _Rate_monotonic_Timeout
 *
 *  This routine processes a period ending.  If the owning thread
 *  is waiting for the period, that thread is unblocked and the
 *  period reinitiated.  Otherwise, the period is expired.
 *  This routine is called by the watchdog handler.
 *
 *  Input parameters:
 *    id - period id
 *
 *  Output parameters: NONE
 */

void _Rate_monotonic_Timeout(
  Objects_Id  id,
  void       *ignored
)
{
  Rate_monotonic_Control *the_period;
  Objects_Locations              location;
  Thread_Control         *the_thread;

  the_period = _Rate_monotonic_Get( id, &location );
  switch ( location ) {
    case OBJECTS_ERROR:
    case OBJECTS_REMOTE:  /* impossible */
      break;
    case OBJECTS_LOCAL:
      the_thread = the_period->owner;
      if ( _States_Is_waiting_for_period( the_thread->current_state ) &&
            the_thread->Wait.id == the_period->Object.id ) {
        _Thread_Unblock( the_thread );
        _Watchdog_Reset( &the_period->Timer );
      }
      else
        the_period->state = RATE_MONOTONIC_EXPIRED;
      _Thread_Unnest_dispatch();
      break;
  }
}