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221 giacomo 1
/*
2
 * Project: S.Ha.R.K.
3
 *
4
 * Coordinators:
5
 *   Giorgio Buttazzo    <giorgio@sssup.it>
6
 *   Paolo Gai           <pj@gandalf.sssup.it>
7
 *
8
 * Authors     :
9
 *   Trimarchi Michael   <trimarchi@gandalf.sssup.it>
10
 *   (see the web pages for full authors list)
11
 *
12
 * ReTiS Lab (Scuola Superiore S.Anna - Pisa - Italy)
13
 *
14
 * http://www.sssup.it
15
 * http://retis.sssup.it
16
 * http://shark.sssup.it
17
 */
18
 
19
/*
20
 * Copyright (C) 2000 Paolo Gai
21
 *
22
 * This program is free software; you can redistribute it and/or modify
23
 * it under the terms of the GNU General Public License as published by
24
 * the Free Software Foundation; either version 2 of the License, or
25
 * (at your option) any later version.
26
 *
27
 * This program is distributed in the hope that it will be useful,
28
 * but WITHOUT ANY WARR2ANTY; without even the implied waRR2anty of
29
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
30
 * GNU General Public License for more details.
31
 *
32
 * You should have received a copy of the GNU General Public License
33
 * along with this program; if not, write to the Free Software
34
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
35
 *
36
 */
37
 
38
 
39
#include <ll/stdio.h>
40
#include <ll/string.h>
41
#include <kernel/model.h>
42
#include <kernel/descr.h>
43
#include <kernel/var.h>
44
#include <kernel/func.h>
45
#include "posixstar.h"
241 giacomo 46
#include "fsf_server.h"
221 giacomo 47
 
48
//#define POSIXSTAR_DEBUG
49
 
50
/*+ Status used in the level +*/
51
#define POSIXSTAR_READY   MODULE_STATUS_BASE
52
 
53
#define POSIXSTAR_CHANGE_LEVEL 1
54
 
55
/*+ the level redefinition for the Round Robin level +*/
56
typedef struct {
57
  level_des l;          /*+ the standard level descriptor          +*/
58
 
59
  int nact[MAX_PROC];   /*+ number of pending activations          +*/
60
 
61
  int priority[MAX_PROC]; /*+ priority of each task                +*/
62
 
63
  IQUEUE *ready;        /*+ the ready queue array                  +*/
64
 
65
  int slice;            /*+ the level's time slice                 +*/
66
 
67
//  the multiboot is not usefull for this module
68
//  struct multiboot_info *multiboot; /*+ used if the level have to insert
69
//                                        the main task +*/
70
 
71
  int maxpriority;      /*+ the priority are from 0 to maxpriority
72
                            (i.e 0 to 31)                          +*/
73
 
74
  int yielding;         /*+ equal to 1 when a sched_yield is called +*/
75
 
76
  int budget[MAX_PROC];
77
 
78
  PID activated;
79
  int scheduling_level;
296 trimarchi 80
  int cap_lev;
81
  struct timespec cap_lasttime;
221 giacomo 82
 
83
} POSIXSTAR_level_des;
84
 
296 trimarchi 85
 
86
 
87
static void capacity_handler(void *l)
88
{
89
  POSIXSTAR_level_des *lev = l;
90
  lev->cap_lev = NIL;
91
  event_need_reschedule();
92
}
221 giacomo 93
/* the private scheduler choice a task and insert in cbsstar module */
94
/* This is not efficient but very fair :-)
95
   The need of all this stuff is because if a task execute a long time
96
   due to (shadow!) priority inheritance, then the task shall go to the
97
   tail of the queue many times... */
98
 
99
static void POSIXSTAR_private_scheduler(POSIXSTAR_level_des * lev)
100
{
101
  /* the old posix scheduler select the private job for CBS */
102
  PID p = NIL;
103
 
104
  int prio;
105
 
106
  prio = lev->maxpriority;
107
 
108
  for (;;) {
109
    p = iq_query_first(&lev->ready[prio]);
110
    if (p == NIL) {
111
      if (prio) {
112
        prio--;
113
        continue;
114
      }
115
      else {
116
        p=NIL;
117
	break;
118
      }
119
    }
120
 
296 trimarchi 121
    if ((proc_table[p].control /* & CONTROL_CAP */) &&
221 giacomo 122
        (proc_table[p].avail_time <= 0)) {
298 giacomo 123
      while (proc_table[p].avail_time<=0)
221 giacomo 124
  	proc_table[p].avail_time += proc_table[p].wcet;
125
      iq_extract(p,&lev->ready[prio]);
126
      iq_insertlast(p,&lev->ready[prio]);
127
    }
128
    else {
129
      break;
130
    }
131
  }
132
 
133
  if (p!=lev->activated) {
134
    if (lev->activated != NIL )  {
135
     level_table[ lev->scheduling_level ]->
136
       private_extract(lev->scheduling_level, lev->activated);
137
   }
138
   lev->activated = p;
139
 
140
   if (p != NIL) {
141
     BUDGET_TASK_MODEL b;
142
     budget_task_default_model(b, lev->budget[p]);
143
     #ifdef POSIXSTAR_DEBUG
144
       kern_printf("(PS:SchAct:%d:%d)",p,lev->budget[p]);
145
     #endif
146
     level_table[ lev->scheduling_level ]->
147
       private_insert(lev->scheduling_level, p, (TASK_MODEL *)&b);
148
   }
149
 }
150
}
151
 
152
static int POSIXSTAR_public_eligible(LEVEL l, PID p)
153
{
154
  POSIXSTAR_level_des *lev = (POSIXSTAR_level_des *)(level_table[l]);
296 trimarchi 155
  return level_table[ lev->scheduling_level ]->
221 giacomo 156
      private_eligible(lev->scheduling_level,p);
296 trimarchi 157
 
221 giacomo 158
  return 0;
159
}
160
 
296 trimarchi 161
 
162
static void POSIXSTAR_account_capacity(POSIXSTAR_level_des *lev, PID p)
163
{
164
	  struct timespec ty;
165
	    TIME tx;
166
 
167
	      SUBTIMESPEC(&schedule_time, &lev->cap_lasttime, &ty);
168
	        tx = TIMESPEC2USEC(&ty);
169
 
170
		  proc_table[p].avail_time -= tx;
171
		    //kern_printf("avail time pid %d , %d", p, proc_table[p].avail_time);
172
 
173
}
174
 
175
 
221 giacomo 176
static int POSIXSTAR_public_create(LEVEL l, PID p, TASK_MODEL *m)
177
{
178
  POSIXSTAR_level_des *lev = (POSIXSTAR_level_des *)(level_table[l]);
179
  NRT_TASK_MODEL *nrt;
180
 
181
  /* DEBUG */
182
  #ifdef POSIXSTAR_DEBUG
183
    kern_printf("(PS:Crt:%d)",p);
184
  #endif
185
 
186
  if (m->pclass != NRT_PCLASS) return -1;
187
  if (m->level != 0 && m->level != l) return -1;
188
 
189
  nrt = (NRT_TASK_MODEL *)m;
190
 
191
  /* the task state is set at SLEEP by the general task_create */
192
 
193
  /* I used the wcet field because using wcet can account if a task
194
     consume more than the timeslice... */
195
 
196
  if (nrt->inherit == NRT_INHERIT_SCHED &&
197
      proc_table[exec_shadow].task_level == l) {
198
    /* We inherit the scheduling properties if the scheduling level
199
       *is* the same */
200
    lev->priority[p] = lev->priority[exec_shadow];
201
 
202
    proc_table[p].avail_time = proc_table[exec_shadow].avail_time;
203
    proc_table[p].wcet       = proc_table[exec_shadow].wcet;
204
 
296 trimarchi 205
    proc_table[p].control = (proc_table[p].control & ~CONTROL_CAP); //|
206
                            //(proc_table[exec_shadow].control & CONTROL_CAP);
221 giacomo 207
 
208
    lev->nact[p] = (lev->nact[exec_shadow] == -1) ? -1 : 0;
209
  }
210
  else {
211
    if (nrt->weight<=lev->maxpriority)
212
      lev->priority[p] = nrt->weight;
213
    else lev->priority[p]=lev->maxpriority;
214
 
215
    if (nrt->slice) {
216
      proc_table[p].avail_time = nrt->slice;
217
      proc_table[p].wcet       = nrt->slice;
218
    }
219
    else {
220
      proc_table[p].avail_time = lev->slice;
221
      proc_table[p].wcet       = lev->slice;
222
    }
296 trimarchi 223
 /*
221 giacomo 224
    if (nrt->policy == NRT_RR_POLICY) {
225
      proc_table[p].control   |= CONTROL_CAP;
226
    }
296 trimarchi 227
   */
221 giacomo 228
    if (nrt->arrivals == SAVE_ARRIVALS)
229
      lev->nact[p] = 0;
230
    else
231
      lev->nact[p] = -1;
232
 
233
  }
234
 
235
  return 0; /* OK */
236
}
237
 
238
static void POSIXSTAR_public_dispatch(LEVEL l, PID p, int nostop)
239
{
240
  POSIXSTAR_level_des *lev = (POSIXSTAR_level_des *)(level_table[l]);
296 trimarchi 241
  struct timespec ty;
221 giacomo 242
  /* the task state is set EXE by the scheduler()
243
     we extract the task from the ready queue
244
     NB: we can't assume that p is the first task in the queue!!! */
245
 
246
  #ifdef POSIXSTAR_DEBUG
296 trimarchi 247
     if( !nostop) kern_printf("(PS:Dsp:%d)",p); else
248
	 kern_printf("(PS:Dsp_shad:%d)",p);
221 giacomo 249
  #endif
296 trimarchi 250
  if (!nostop || proc_table[exec].task_level==l) {
251
    TIMESPEC_ASSIGN(&ty, &schedule_time);
252
    TIMESPEC_ASSIGN(&lev->cap_lasttime, &schedule_time);
253
 
254
    /* ...and finally, we have to post a capacity event on exec task because the shadow_task consume
255
     *        capacity on exe task always */
256
    ADDUSEC2TIMESPEC(proc_table[exec].avail_time ,&ty);
257
    lev->cap_lev = kern_event_post(&ty,capacity_handler, lev);
221 giacomo 258
    level_table[lev->scheduling_level]->private_dispatch(lev->scheduling_level, p, nostop);
296 trimarchi 259
  }
260
  else
261
	level_table[proc_table[exec].task_level]->public_dispatch(proc_table[exec].task_level, p, nostop);
221 giacomo 262
 
263
}
264
 
226 giacomo 265
static void POSIXSTAR_public_epilogue(LEVEL l, PID p)
266
{
267
  POSIXSTAR_level_des *lev = (POSIXSTAR_level_des *)(level_table[l]);
221 giacomo 268
 
226 giacomo 269
  #ifdef POSIXSTAR_DEBUG
270
    kern_printf("(PS:Epi:%d)",p);
271
  #endif
272
 
296 trimarchi 273
 if (lev->cap_lev!=NIL) {
274
	kern_event_delete(lev->cap_lev);
275
	lev->cap_lev=NIL;
276
 }
277
 
278
 if (/* p==exec && lev->activated==p */
279
      proc_table[exec].task_level==l ) {
280
    POSIXSTAR_account_capacity(lev,exec);
221 giacomo 281
    if (lev->yielding) {
282
      lev->yielding = 0;
296 trimarchi 283
      iq_extract(p,&lev->ready[lev->priority[exec]]);
284
      iq_insertlast(p,&lev->ready[lev->priority[exec]]);
221 giacomo 285
    }
286
    /* check if the slice is finished and insert the task in the coPOSIXect
287
       qqueue position */
296 trimarchi 288
    else if (/* proc_table[p].control & CONTROL_CAP && */
289
           proc_table[exec].avail_time <= 0) {
221 giacomo 290
 
296 trimarchi 291
      iq_extract(exec,&lev->ready[lev->priority[exec]]);
292
      iq_insertlast(exec,&lev->ready[lev->priority[exec]]);
221 giacomo 293
 
294
      POSIXSTAR_private_scheduler(lev);
296 trimarchi 295
      if (exec==lev->activated)
221 giacomo 296
	level_table[lev->scheduling_level]->private_epilogue(lev->scheduling_level,p);
297
 
298
    }
299
    else  {
300
 
301
      level_table[lev->scheduling_level]->private_epilogue(lev->scheduling_level,p);
302
 
303
      POSIXSTAR_private_scheduler(lev);
304
 
305
    }
306
 
307
    proc_table[p].status = POSIXSTAR_READY;
308
 
296 trimarchi 309
  } else
310
       level_table[proc_table[exec].task_level]->public_epilogue(proc_table[exec].task_level,p);
311
 
221 giacomo 312
 
313
 
314
}
315
 
316
static void POSIXSTAR_internal_activate(POSIXSTAR_level_des *lev, PID p)
317
{
318
 
319
  /* Insert task in the correct position */
320
  proc_table[p].status = POSIXSTAR_READY;
321
  iq_insertlast(p,&lev->ready[lev->priority[p]]);
322
 
323
}
324
 
325
 
326
static void POSIXSTAR_public_activate(LEVEL l, PID p)
327
{
328
  POSIXSTAR_level_des *lev = (POSIXSTAR_level_des *)(level_table[l]);
329
 
330
  /* Test if we are trying to activate a non sleeping task    */
331
  /* save activation (only if needed...) */
332
  if (proc_table[p].status != SLEEP) {
333
    if (lev->nact[p] != -1)
334
      lev->nact[p]++;
335
    return;
336
  }
337
 
338
  #ifdef POSIXSTAR_DEBUG
339
    kern_printf("(PS:Act:%d)",p);
340
  #endif
341
 
342
  POSIXSTAR_internal_activate(lev, p);
343
  POSIXSTAR_private_scheduler(lev);
344
 
345
}
346
 
347
 
348
static void POSIXSTAR_public_unblock(LEVEL l, PID p)
349
{
350
  POSIXSTAR_level_des *lev = (POSIXSTAR_level_des *)(level_table[l]);
351
 
352
  /* Similar to POSIX_task_activate, but we don't check in what state
353
     the task is */
354
 
355
  #ifdef POSIXSTAR_DEBUG
356
    kern_printf("(PS:UnBlk:%d)",p);
357
  #endif
358
  /* Insert task in the coPOSIXect position */
359
  proc_table[p].status = POSIXSTAR_READY;
360
  iq_insertlast(p,&lev->ready[lev->priority[p]]);
361
  POSIXSTAR_private_scheduler(lev);
362
 
363
}
364
 
365
static void POSIXSTAR_public_block(LEVEL l, PID p)
366
{
367
  POSIXSTAR_level_des *lev = (POSIXSTAR_level_des *)(level_table[l]);
368
 
369
  /* Extract the running task from the level
370
     . we have already extract it from the ready queue at the dispatch time.
371
     . the capacity event have to be removed by the generic kernel
372
     . the wcet don't need modification...
373
     . the state of the task is set by the calling function
374
 
375
     So, we do nothing!!!
376
  */
377
 
378
  #ifdef POSIXSTAR_DEBUG
379
    kern_printf("(PS:Blk:%d)", p);
380
  #endif
381
 
382
  iq_extract(p,&lev->ready[lev->priority[p]]);
296 trimarchi 383
  //if (p==lev->activated) lev->activated = NIL;
221 giacomo 384
  POSIXSTAR_private_scheduler(lev);
385
 
386
}
387
 
388
static int POSIXSTAR_public_message(LEVEL l, PID p, void *m)
389
{
390
  POSIXSTAR_level_des *lev = (POSIXSTAR_level_des *)(level_table[l]);
391
 
392
  #ifdef POSIXSTAR_DEBUG
393
    kern_printf("(PS:Msg:%d)",p);
394
  #endif
395
 
396
  switch ((long)(m)) {
397
 
398
    /* Task EndCycle */
399
    case (long)(NULL):
400
 
401
      if (lev->nact[p] > 0) {
402
        /* continue!!!! */
403
        lev->nact[p]--;
404
        iq_extract(p,&lev->ready[lev->priority[p]]);
405
        iq_insertfirst(p,&lev->ready[lev->priority[p]]);
406
        proc_table[p].status = POSIXSTAR_READY;
407
      }
408
      else {
409
        proc_table[p].status = SLEEP;
410
        iq_extract(p,&lev->ready[lev->priority[p]]);
411
      }
412
 
413
      jet_update_endcycle(); /* Update the Jet data... */
414
      POSIXSTAR_private_scheduler(lev);
415
 
416
      break;
417
 
418
    /* Task Disable */
419
    case (long)(1):
420
 
421
      break;
422
 
423
    default:
424
 
241 giacomo 425
      break;
221 giacomo 426
 
427
  }
428
 
429
  return 0;
430
 
431
}
432
 
433
static void POSIXSTAR_public_end(LEVEL l, PID p)
434
{
435
  POSIXSTAR_level_des *lev = (POSIXSTAR_level_des *)(level_table[l]);
436
 
437
  #ifdef POSIXSTAR_DEBUG
438
    kern_printf("(PS:End:%d)", p);
439
  #endif
440
 
441
  lev->nact[p] = -1;
348 trimarchi 442
  /* extract task from the queue */
443
  iq_extract(p,&lev->ready[lev->priority[p]]);
221 giacomo 444
 
445
  /* then, we insert the task in the free queue */
446
  proc_table[p].status = FREE;
447
  iq_priority_insert(p,NULL);
448
  POSIXSTAR_private_scheduler(lev);
449
 
450
}
451
 
452
/* Registration functions */
453
 
454
/*+ Registration function:
455
    TIME slice                the slice for the Round Robin queue +*/
456
LEVEL POSIXSTAR_register_level(int master, TIME slice,
457
                       int prioritylevels)
458
{
459
  LEVEL l;            /* the level that we register */
460
  POSIXSTAR_level_des *lev;  /* for readableness only */
461
  PID i;              /* a counter */
462
  int x;              /* a counter */
463
 
464
  #ifdef POSIXSTRA_DEBUG
465
    kern_printf("POSIXSTAR_register_level\n");
466
  #endif
467
 
468
  l = level_alloc_descriptor(sizeof(POSIXSTAR_level_des));
469
 
470
  lev = (POSIXSTAR_level_des *)level_table[l];
471
 
270 giacomo 472
  lev->l.public_guarantee = NULL;
221 giacomo 473
  lev->l.public_create    = POSIXSTAR_public_create;
474
  lev->l.public_end       = POSIXSTAR_public_end;
475
  lev->l.public_dispatch  = POSIXSTAR_public_dispatch;
476
  lev->l.public_epilogue  = POSIXSTAR_public_epilogue;
477
  lev->l.public_activate  = POSIXSTAR_public_activate;
478
  lev->l.public_unblock   = POSIXSTAR_public_unblock;
479
  lev->l.public_block     = POSIXSTAR_public_block;
480
  lev->l.public_message   = POSIXSTAR_public_message;
481
  lev->l.public_eligible  = POSIXSTAR_public_eligible;
482
 
483
  /* fill the POSIX descriptor part */
484
  for (i = 0; i < MAX_PROC; i++) {
485
    lev->nact[i] = -1;
486
    lev->budget[i] = -1;
487
  }
488
 
489
  lev->maxpriority = prioritylevels - 1;
490
 
491
  lev->ready = (IQUEUE *)kern_alloc(sizeof(IQUEUE) * prioritylevels);
492
 
493
  for (x = 0; x < prioritylevels; x++)
494
    iq_init(&lev->ready[x], NULL, 0);
495
 
496
  if (slice < POSIXSTAR_MINIMUM_SLICE) slice = POSIXSTAR_MINIMUM_SLICE;
497
  if (slice > POSIXSTAR_MAXIMUM_SLICE) slice = POSIXSTAR_MAXIMUM_SLICE;
498
  lev->slice = slice;
499
  lev->activated = NIL;
500
  lev->scheduling_level = master;
298 giacomo 501
  lev->cap_lev = NIL;
296 trimarchi 502
  NULL_TIMESPEC(&lev->cap_lasttime);
503
 
221 giacomo 504
  return l;
505
 
506
}
507
 
508
int POSIXSTAR_setbudget(LEVEL l, PID p, int budget)
509
{
510
 
511
  POSIXSTAR_level_des *lev = (POSIXSTAR_level_des *)(level_table[l]);
512
 
513
  lev->budget[p] = budget;
514
 
515
  return 0;
516
 
517
}
518
 
519
int POSIXSTAR_getbudget(LEVEL l, PID p)
520
{
521
 
522
  POSIXSTAR_level_des *lev = (POSIXSTAR_level_des *)(level_table[l]);
523
 
524
  return lev->budget[p];
525
 
526
}
527
 
528
int POSIXSTAR_budget_has_thread(LEVEL l, int budget)
529
{
530
 
531
  POSIXSTAR_level_des *lev = (POSIXSTAR_level_des *)(level_table[l]);
532
  int i;
533
 
534
  for(i = 0; i< MAX_PROC; i++)
535
    if (lev->budget[i] == budget) return 1;
536
 
537
  return 0;
538
 
539
}
540
 
541
/*+ this function forces the running task to go to his queue tail;
542
    (it works only on the POSIX level) +*/
543
int POSIXSTAR_sched_yield(LEVEL l)
544
{
545
  POSIXSTAR_level_des *lev = (POSIXSTAR_level_des *)(level_table[l]);
546
 
547
  if (proc_table[exec_shadow].task_level != l)
548
    return -1;
549
 
550
  proc_table[exec_shadow].context = kern_context_save();
551
  lev->yielding = 1;
552
  scheduler();
553
  kern_context_load(proc_table[exec_shadow].context);
554
  return 0;
555
}
556
 
557
/*+ this function returns the maximum level allowed for the POSIX level +*/
558
int POSIXSTAR_get_priority_max(LEVEL l)
559
{
560
  POSIXSTAR_level_des *lev = (POSIXSTAR_level_des *)(level_table[l]);
561
  return lev->maxpriority;
562
}
563
 
564
/*+ this function returns the default timeslice for the POSIX level +*/
565
int POSIXSTAR_rr_get_interval(LEVEL l)
566
{
567
  POSIXSTAR_level_des *lev = (POSIXSTAR_level_des *)(level_table[l]);
568
  return lev->slice;
569
}
570
 
571
/*+ this functions returns some paramaters of a task;
572
    policy must be NRT_RR_POLICY or NRT_FIFO_POLICY;
573
    priority must be in the range [0..prioritylevels]
574
    returns ENOSYS or ESRCH if there are problems +*/
575
int POSIXSTAR_getschedparam(LEVEL l, PID p, int *policy, int *priority)
576
{
577
  if (p<0 || p>= MAX_PROC || proc_table[p].status == FREE)
578
    return ESRCH;
579
 
580
  if (proc_table[p].task_level != l)
581
    return ENOSYS;
582
 
296 trimarchi 583
  //if (proc_table[p].control & CONTROL_CAP)
221 giacomo 584
    *policy = NRT_RR_POLICY;
296 trimarchi 585
  //else
586
  //  *policy = NRT_FIFO_POLICY;
221 giacomo 587
 
588
  *priority = ((POSIXSTAR_level_des *)(level_table[l]))->priority[p];
589
 
590
  return 0;
591
}
592
 
593
/*+ this functions sets paramaters of a task +*/
594
int POSIXSTAR_setschedparam(LEVEL l, PID p, int policy, int priority)
595
{
596
  POSIXSTAR_level_des *lev = (POSIXSTAR_level_des *)(level_table[l]);
597
 
598
  if (p<0 || p>= MAX_PROC || proc_table[p].status == FREE)
599
    return ESRCH;
600
 
601
  if (proc_table[p].task_level != l)
602
    return ENOSYS;
296 trimarchi 603
/*
221 giacomo 604
  if (policy == SCHED_RR)
605
    proc_table[p].control |= CONTROL_CAP;
606
  else if (policy == SCHED_FIFO)
607
    proc_table[p].control &= ~CONTROL_CAP;
608
  else
609
    return EINVAL;
296 trimarchi 610
*/
221 giacomo 611
  if (lev->priority[p] != priority) {
612
    if (proc_table[p].status == POSIXSTAR_READY) {
613
      iq_extract(p,&lev->ready[lev->priority[p]]);
614
      lev->priority[p] = priority;
615
      iq_insertlast(p,&lev->ready[priority]);
616
    }
617
    else
618
      lev->priority[p] = priority;
619
  }
620
 
621
  return 0;
622
}
623