sched: fix hotplug cpus on ia64
[linux-2.6.git] / kernel / sched_rt.c
1 /*
2  * Real-Time Scheduling Class (mapped to the SCHED_FIFO and SCHED_RR
3  * policies)
4  */
5
6 #ifdef CONFIG_SMP
7
8 static inline int rt_overloaded(struct rq *rq)
9 {
10         return atomic_read(&rq->rd->rto_count);
11 }
12
13 static inline void rt_set_overload(struct rq *rq)
14 {
15         if (!rq->online)
16                 return;
17
18         cpu_set(rq->cpu, rq->rd->rto_mask);
19         /*
20          * Make sure the mask is visible before we set
21          * the overload count. That is checked to determine
22          * if we should look at the mask. It would be a shame
23          * if we looked at the mask, but the mask was not
24          * updated yet.
25          */
26         wmb();
27         atomic_inc(&rq->rd->rto_count);
28 }
29
30 static inline void rt_clear_overload(struct rq *rq)
31 {
32         if (!rq->online)
33                 return;
34
35         /* the order here really doesn't matter */
36         atomic_dec(&rq->rd->rto_count);
37         cpu_clear(rq->cpu, rq->rd->rto_mask);
38 }
39
40 static void update_rt_migration(struct rq *rq)
41 {
42         if (rq->rt.rt_nr_migratory && (rq->rt.rt_nr_running > 1)) {
43                 if (!rq->rt.overloaded) {
44                         rt_set_overload(rq);
45                         rq->rt.overloaded = 1;
46                 }
47         } else if (rq->rt.overloaded) {
48                 rt_clear_overload(rq);
49                 rq->rt.overloaded = 0;
50         }
51 }
52 #endif /* CONFIG_SMP */
53
54 static inline struct task_struct *rt_task_of(struct sched_rt_entity *rt_se)
55 {
56         return container_of(rt_se, struct task_struct, rt);
57 }
58
59 static inline int on_rt_rq(struct sched_rt_entity *rt_se)
60 {
61         return !list_empty(&rt_se->run_list);
62 }
63
64 #ifdef CONFIG_RT_GROUP_SCHED
65
66 static inline u64 sched_rt_runtime(struct rt_rq *rt_rq)
67 {
68         if (!rt_rq->tg)
69                 return RUNTIME_INF;
70
71         return rt_rq->rt_runtime;
72 }
73
74 static inline u64 sched_rt_period(struct rt_rq *rt_rq)
75 {
76         return ktime_to_ns(rt_rq->tg->rt_bandwidth.rt_period);
77 }
78
79 #define for_each_leaf_rt_rq(rt_rq, rq) \
80         list_for_each_entry(rt_rq, &rq->leaf_rt_rq_list, leaf_rt_rq_list)
81
82 static inline struct rq *rq_of_rt_rq(struct rt_rq *rt_rq)
83 {
84         return rt_rq->rq;
85 }
86
87 static inline struct rt_rq *rt_rq_of_se(struct sched_rt_entity *rt_se)
88 {
89         return rt_se->rt_rq;
90 }
91
92 #define for_each_sched_rt_entity(rt_se) \
93         for (; rt_se; rt_se = rt_se->parent)
94
95 static inline struct rt_rq *group_rt_rq(struct sched_rt_entity *rt_se)
96 {
97         return rt_se->my_q;
98 }
99
100 static void enqueue_rt_entity(struct sched_rt_entity *rt_se);
101 static void dequeue_rt_entity(struct sched_rt_entity *rt_se);
102
103 static void sched_rt_rq_enqueue(struct rt_rq *rt_rq)
104 {
105         struct sched_rt_entity *rt_se = rt_rq->rt_se;
106
107         if (rt_se && !on_rt_rq(rt_se) && rt_rq->rt_nr_running) {
108                 struct task_struct *curr = rq_of_rt_rq(rt_rq)->curr;
109
110                 enqueue_rt_entity(rt_se);
111                 if (rt_rq->highest_prio < curr->prio)
112                         resched_task(curr);
113         }
114 }
115
116 static void sched_rt_rq_dequeue(struct rt_rq *rt_rq)
117 {
118         struct sched_rt_entity *rt_se = rt_rq->rt_se;
119
120         if (rt_se && on_rt_rq(rt_se))
121                 dequeue_rt_entity(rt_se);
122 }
123
124 static inline int rt_rq_throttled(struct rt_rq *rt_rq)
125 {
126         return rt_rq->rt_throttled && !rt_rq->rt_nr_boosted;
127 }
128
129 static int rt_se_boosted(struct sched_rt_entity *rt_se)
130 {
131         struct rt_rq *rt_rq = group_rt_rq(rt_se);
132         struct task_struct *p;
133
134         if (rt_rq)
135                 return !!rt_rq->rt_nr_boosted;
136
137         p = rt_task_of(rt_se);
138         return p->prio != p->normal_prio;
139 }
140
141 #ifdef CONFIG_SMP
142 static inline cpumask_t sched_rt_period_mask(void)
143 {
144         return cpu_rq(smp_processor_id())->rd->span;
145 }
146 #else
147 static inline cpumask_t sched_rt_period_mask(void)
148 {
149         return cpu_online_map;
150 }
151 #endif
152
153 static inline
154 struct rt_rq *sched_rt_period_rt_rq(struct rt_bandwidth *rt_b, int cpu)
155 {
156         return container_of(rt_b, struct task_group, rt_bandwidth)->rt_rq[cpu];
157 }
158
159 static inline struct rt_bandwidth *sched_rt_bandwidth(struct rt_rq *rt_rq)
160 {
161         return &rt_rq->tg->rt_bandwidth;
162 }
163
164 #else
165
166 static inline u64 sched_rt_runtime(struct rt_rq *rt_rq)
167 {
168         return rt_rq->rt_runtime;
169 }
170
171 static inline u64 sched_rt_period(struct rt_rq *rt_rq)
172 {
173         return ktime_to_ns(def_rt_bandwidth.rt_period);
174 }
175
176 #define for_each_leaf_rt_rq(rt_rq, rq) \
177         for (rt_rq = &rq->rt; rt_rq; rt_rq = NULL)
178
179 static inline struct rq *rq_of_rt_rq(struct rt_rq *rt_rq)
180 {
181         return container_of(rt_rq, struct rq, rt);
182 }
183
184 static inline struct rt_rq *rt_rq_of_se(struct sched_rt_entity *rt_se)
185 {
186         struct task_struct *p = rt_task_of(rt_se);
187         struct rq *rq = task_rq(p);
188
189         return &rq->rt;
190 }
191
192 #define for_each_sched_rt_entity(rt_se) \
193         for (; rt_se; rt_se = NULL)
194
195 static inline struct rt_rq *group_rt_rq(struct sched_rt_entity *rt_se)
196 {
197         return NULL;
198 }
199
200 static inline void sched_rt_rq_enqueue(struct rt_rq *rt_rq)
201 {
202 }
203
204 static inline void sched_rt_rq_dequeue(struct rt_rq *rt_rq)
205 {
206 }
207
208 static inline int rt_rq_throttled(struct rt_rq *rt_rq)
209 {
210         return rt_rq->rt_throttled;
211 }
212
213 static inline cpumask_t sched_rt_period_mask(void)
214 {
215         return cpu_online_map;
216 }
217
218 static inline
219 struct rt_rq *sched_rt_period_rt_rq(struct rt_bandwidth *rt_b, int cpu)
220 {
221         return &cpu_rq(cpu)->rt;
222 }
223
224 static inline struct rt_bandwidth *sched_rt_bandwidth(struct rt_rq *rt_rq)
225 {
226         return &def_rt_bandwidth;
227 }
228
229 #endif
230
231 static int do_sched_rt_period_timer(struct rt_bandwidth *rt_b, int overrun)
232 {
233         int i, idle = 1;
234         cpumask_t span;
235
236         if (rt_b->rt_runtime == RUNTIME_INF)
237                 return 1;
238
239         span = sched_rt_period_mask();
240         for_each_cpu_mask(i, span) {
241                 int enqueue = 0;
242                 struct rt_rq *rt_rq = sched_rt_period_rt_rq(rt_b, i);
243                 struct rq *rq = rq_of_rt_rq(rt_rq);
244
245                 spin_lock(&rq->lock);
246                 if (rt_rq->rt_time) {
247                         u64 runtime;
248
249                         spin_lock(&rt_rq->rt_runtime_lock);
250                         runtime = rt_rq->rt_runtime;
251                         rt_rq->rt_time -= min(rt_rq->rt_time, overrun*runtime);
252                         if (rt_rq->rt_throttled && rt_rq->rt_time < runtime) {
253                                 rt_rq->rt_throttled = 0;
254                                 enqueue = 1;
255                         }
256                         if (rt_rq->rt_time || rt_rq->rt_nr_running)
257                                 idle = 0;
258                         spin_unlock(&rt_rq->rt_runtime_lock);
259                 }
260
261                 if (enqueue)
262                         sched_rt_rq_enqueue(rt_rq);
263                 spin_unlock(&rq->lock);
264         }
265
266         return idle;
267 }
268
269 #ifdef CONFIG_SMP
270 static int balance_runtime(struct rt_rq *rt_rq)
271 {
272         struct rt_bandwidth *rt_b = sched_rt_bandwidth(rt_rq);
273         struct root_domain *rd = cpu_rq(smp_processor_id())->rd;
274         int i, weight, more = 0;
275         u64 rt_period;
276
277         weight = cpus_weight(rd->span);
278
279         spin_lock(&rt_b->rt_runtime_lock);
280         rt_period = ktime_to_ns(rt_b->rt_period);
281         for_each_cpu_mask(i, rd->span) {
282                 struct rt_rq *iter = sched_rt_period_rt_rq(rt_b, i);
283                 s64 diff;
284
285                 if (iter == rt_rq)
286                         continue;
287
288                 spin_lock(&iter->rt_runtime_lock);
289                 if (iter->rt_runtime == RUNTIME_INF)
290                         goto next;
291
292                 diff = iter->rt_runtime - iter->rt_time;
293                 if (diff > 0) {
294                         do_div(diff, weight);
295                         if (rt_rq->rt_runtime + diff > rt_period)
296                                 diff = rt_period - rt_rq->rt_runtime;
297                         iter->rt_runtime -= diff;
298                         rt_rq->rt_runtime += diff;
299                         more = 1;
300                         if (rt_rq->rt_runtime == rt_period) {
301                                 spin_unlock(&iter->rt_runtime_lock);
302                                 break;
303                         }
304                 }
305 next:
306                 spin_unlock(&iter->rt_runtime_lock);
307         }
308         spin_unlock(&rt_b->rt_runtime_lock);
309
310         return more;
311 }
312
313 static void __disable_runtime(struct rq *rq)
314 {
315         struct root_domain *rd = rq->rd;
316         struct rt_rq *rt_rq;
317
318         if (unlikely(!scheduler_running))
319                 return;
320
321         for_each_leaf_rt_rq(rt_rq, rq) {
322                 struct rt_bandwidth *rt_b = sched_rt_bandwidth(rt_rq);
323                 s64 want;
324                 int i;
325
326                 spin_lock(&rt_b->rt_runtime_lock);
327                 spin_lock(&rt_rq->rt_runtime_lock);
328                 if (rt_rq->rt_runtime == RUNTIME_INF ||
329                                 rt_rq->rt_runtime == rt_b->rt_runtime)
330                         goto balanced;
331                 spin_unlock(&rt_rq->rt_runtime_lock);
332
333                 want = rt_b->rt_runtime - rt_rq->rt_runtime;
334
335                 for_each_cpu_mask(i, rd->span) {
336                         struct rt_rq *iter = sched_rt_period_rt_rq(rt_b, i);
337                         s64 diff;
338
339                         if (iter == rt_rq)
340                                 continue;
341
342                         spin_lock(&iter->rt_runtime_lock);
343                         if (want > 0) {
344                                 diff = min_t(s64, iter->rt_runtime, want);
345                                 iter->rt_runtime -= diff;
346                                 want -= diff;
347                         } else {
348                                 iter->rt_runtime -= want;
349                                 want -= want;
350                         }
351                         spin_unlock(&iter->rt_runtime_lock);
352
353                         if (!want)
354                                 break;
355                 }
356
357                 spin_lock(&rt_rq->rt_runtime_lock);
358                 BUG_ON(want);
359 balanced:
360                 rt_rq->rt_runtime = RUNTIME_INF;
361                 spin_unlock(&rt_rq->rt_runtime_lock);
362                 spin_unlock(&rt_b->rt_runtime_lock);
363         }
364 }
365
366 static void disable_runtime(struct rq *rq)
367 {
368         unsigned long flags;
369
370         spin_lock_irqsave(&rq->lock, flags);
371         __disable_runtime(rq);
372         spin_unlock_irqrestore(&rq->lock, flags);
373 }
374
375 static void __enable_runtime(struct rq *rq)
376 {
377         struct root_domain *rd = rq->rd;
378         struct rt_rq *rt_rq;
379
380         if (unlikely(!scheduler_running))
381                 return;
382
383         for_each_leaf_rt_rq(rt_rq, rq) {
384                 struct rt_bandwidth *rt_b = sched_rt_bandwidth(rt_rq);
385
386                 spin_lock(&rt_b->rt_runtime_lock);
387                 spin_lock(&rt_rq->rt_runtime_lock);
388                 rt_rq->rt_runtime = rt_b->rt_runtime;
389                 rt_rq->rt_time = 0;
390                 spin_unlock(&rt_rq->rt_runtime_lock);
391                 spin_unlock(&rt_b->rt_runtime_lock);
392         }
393 }
394
395 static void enable_runtime(struct rq *rq)
396 {
397         unsigned long flags;
398
399         spin_lock_irqsave(&rq->lock, flags);
400         __enable_runtime(rq);
401         spin_unlock_irqrestore(&rq->lock, flags);
402 }
403
404 #endif
405
406 static inline int rt_se_prio(struct sched_rt_entity *rt_se)
407 {
408 #ifdef CONFIG_RT_GROUP_SCHED
409         struct rt_rq *rt_rq = group_rt_rq(rt_se);
410
411         if (rt_rq)
412                 return rt_rq->highest_prio;
413 #endif
414
415         return rt_task_of(rt_se)->prio;
416 }
417
418 static int sched_rt_runtime_exceeded(struct rt_rq *rt_rq)
419 {
420         u64 runtime = sched_rt_runtime(rt_rq);
421
422         if (runtime == RUNTIME_INF)
423                 return 0;
424
425         if (rt_rq->rt_throttled)
426                 return rt_rq_throttled(rt_rq);
427
428         if (sched_rt_runtime(rt_rq) >= sched_rt_period(rt_rq))
429                 return 0;
430
431 #ifdef CONFIG_SMP
432         if (rt_rq->rt_time > runtime) {
433                 spin_unlock(&rt_rq->rt_runtime_lock);
434                 balance_runtime(rt_rq);
435                 spin_lock(&rt_rq->rt_runtime_lock);
436
437                 runtime = sched_rt_runtime(rt_rq);
438                 if (runtime == RUNTIME_INF)
439                         return 0;
440         }
441 #endif
442
443         if (rt_rq->rt_time > runtime) {
444                 rt_rq->rt_throttled = 1;
445                 if (rt_rq_throttled(rt_rq)) {
446                         sched_rt_rq_dequeue(rt_rq);
447                         return 1;
448                 }
449         }
450
451         return 0;
452 }
453
454 /*
455  * Update the current task's runtime statistics. Skip current tasks that
456  * are not in our scheduling class.
457  */
458 static void update_curr_rt(struct rq *rq)
459 {
460         struct task_struct *curr = rq->curr;
461         struct sched_rt_entity *rt_se = &curr->rt;
462         struct rt_rq *rt_rq = rt_rq_of_se(rt_se);
463         u64 delta_exec;
464
465         if (!task_has_rt_policy(curr))
466                 return;
467
468         delta_exec = rq->clock - curr->se.exec_start;
469         if (unlikely((s64)delta_exec < 0))
470                 delta_exec = 0;
471
472         schedstat_set(curr->se.exec_max, max(curr->se.exec_max, delta_exec));
473
474         curr->se.sum_exec_runtime += delta_exec;
475         curr->se.exec_start = rq->clock;
476         cpuacct_charge(curr, delta_exec);
477
478         for_each_sched_rt_entity(rt_se) {
479                 rt_rq = rt_rq_of_se(rt_se);
480
481                 spin_lock(&rt_rq->rt_runtime_lock);
482                 rt_rq->rt_time += delta_exec;
483                 if (sched_rt_runtime_exceeded(rt_rq))
484                         resched_task(curr);
485                 spin_unlock(&rt_rq->rt_runtime_lock);
486         }
487 }
488
489 static inline
490 void inc_rt_tasks(struct sched_rt_entity *rt_se, struct rt_rq *rt_rq)
491 {
492         WARN_ON(!rt_prio(rt_se_prio(rt_se)));
493         rt_rq->rt_nr_running++;
494 #if defined CONFIG_SMP || defined CONFIG_RT_GROUP_SCHED
495         if (rt_se_prio(rt_se) < rt_rq->highest_prio) {
496                 struct rq *rq = rq_of_rt_rq(rt_rq);
497
498                 rt_rq->highest_prio = rt_se_prio(rt_se);
499 #ifdef CONFIG_SMP
500                 if (rq->online)
501                         cpupri_set(&rq->rd->cpupri, rq->cpu,
502                                    rt_se_prio(rt_se));
503 #endif
504         }
505 #endif
506 #ifdef CONFIG_SMP
507         if (rt_se->nr_cpus_allowed > 1) {
508                 struct rq *rq = rq_of_rt_rq(rt_rq);
509
510                 rq->rt.rt_nr_migratory++;
511         }
512
513         update_rt_migration(rq_of_rt_rq(rt_rq));
514 #endif
515 #ifdef CONFIG_RT_GROUP_SCHED
516         if (rt_se_boosted(rt_se))
517                 rt_rq->rt_nr_boosted++;
518
519         if (rt_rq->tg)
520                 start_rt_bandwidth(&rt_rq->tg->rt_bandwidth);
521 #else
522         start_rt_bandwidth(&def_rt_bandwidth);
523 #endif
524 }
525
526 static inline
527 void dec_rt_tasks(struct sched_rt_entity *rt_se, struct rt_rq *rt_rq)
528 {
529 #ifdef CONFIG_SMP
530         int highest_prio = rt_rq->highest_prio;
531 #endif
532
533         WARN_ON(!rt_prio(rt_se_prio(rt_se)));
534         WARN_ON(!rt_rq->rt_nr_running);
535         rt_rq->rt_nr_running--;
536 #if defined CONFIG_SMP || defined CONFIG_RT_GROUP_SCHED
537         if (rt_rq->rt_nr_running) {
538                 struct rt_prio_array *array;
539
540                 WARN_ON(rt_se_prio(rt_se) < rt_rq->highest_prio);
541                 if (rt_se_prio(rt_se) == rt_rq->highest_prio) {
542                         /* recalculate */
543                         array = &rt_rq->active;
544                         rt_rq->highest_prio =
545                                 sched_find_first_bit(array->bitmap);
546                 } /* otherwise leave rq->highest prio alone */
547         } else
548                 rt_rq->highest_prio = MAX_RT_PRIO;
549 #endif
550 #ifdef CONFIG_SMP
551         if (rt_se->nr_cpus_allowed > 1) {
552                 struct rq *rq = rq_of_rt_rq(rt_rq);
553                 rq->rt.rt_nr_migratory--;
554         }
555
556         if (rt_rq->highest_prio != highest_prio) {
557                 struct rq *rq = rq_of_rt_rq(rt_rq);
558
559                 if (rq->online)
560                         cpupri_set(&rq->rd->cpupri, rq->cpu,
561                                    rt_rq->highest_prio);
562         }
563
564         update_rt_migration(rq_of_rt_rq(rt_rq));
565 #endif /* CONFIG_SMP */
566 #ifdef CONFIG_RT_GROUP_SCHED
567         if (rt_se_boosted(rt_se))
568                 rt_rq->rt_nr_boosted--;
569
570         WARN_ON(!rt_rq->rt_nr_running && rt_rq->rt_nr_boosted);
571 #endif
572 }
573
574 static void enqueue_rt_entity(struct sched_rt_entity *rt_se)
575 {
576         struct rt_rq *rt_rq = rt_rq_of_se(rt_se);
577         struct rt_prio_array *array = &rt_rq->active;
578         struct rt_rq *group_rq = group_rt_rq(rt_se);
579
580         if (group_rq && rt_rq_throttled(group_rq))
581                 return;
582
583         if (rt_se->nr_cpus_allowed == 1)
584                 list_add_tail(&rt_se->run_list,
585                               array->xqueue + rt_se_prio(rt_se));
586         else
587                 list_add_tail(&rt_se->run_list,
588                               array->squeue + rt_se_prio(rt_se));
589
590         __set_bit(rt_se_prio(rt_se), array->bitmap);
591
592         inc_rt_tasks(rt_se, rt_rq);
593 }
594
595 static void dequeue_rt_entity(struct sched_rt_entity *rt_se)
596 {
597         struct rt_rq *rt_rq = rt_rq_of_se(rt_se);
598         struct rt_prio_array *array = &rt_rq->active;
599
600         list_del_init(&rt_se->run_list);
601         if (list_empty(array->squeue + rt_se_prio(rt_se))
602             && list_empty(array->xqueue + rt_se_prio(rt_se)))
603                 __clear_bit(rt_se_prio(rt_se), array->bitmap);
604
605         dec_rt_tasks(rt_se, rt_rq);
606 }
607
608 /*
609  * Because the prio of an upper entry depends on the lower
610  * entries, we must remove entries top - down.
611  */
612 static void dequeue_rt_stack(struct task_struct *p)
613 {
614         struct sched_rt_entity *rt_se, *back = NULL;
615
616         rt_se = &p->rt;
617         for_each_sched_rt_entity(rt_se) {
618                 rt_se->back = back;
619                 back = rt_se;
620         }
621
622         for (rt_se = back; rt_se; rt_se = rt_se->back) {
623                 if (on_rt_rq(rt_se))
624                         dequeue_rt_entity(rt_se);
625         }
626 }
627
628 /*
629  * Adding/removing a task to/from a priority array:
630  */
631 static void enqueue_task_rt(struct rq *rq, struct task_struct *p, int wakeup)
632 {
633         struct sched_rt_entity *rt_se = &p->rt;
634
635         if (wakeup)
636                 rt_se->timeout = 0;
637
638         dequeue_rt_stack(p);
639
640         /*
641          * enqueue everybody, bottom - up.
642          */
643         for_each_sched_rt_entity(rt_se)
644                 enqueue_rt_entity(rt_se);
645 }
646
647 static void dequeue_task_rt(struct rq *rq, struct task_struct *p, int sleep)
648 {
649         struct sched_rt_entity *rt_se = &p->rt;
650         struct rt_rq *rt_rq;
651
652         update_curr_rt(rq);
653
654         dequeue_rt_stack(p);
655
656         /*
657          * re-enqueue all non-empty rt_rq entities.
658          */
659         for_each_sched_rt_entity(rt_se) {
660                 rt_rq = group_rt_rq(rt_se);
661                 if (rt_rq && rt_rq->rt_nr_running)
662                         enqueue_rt_entity(rt_se);
663         }
664 }
665
666 /*
667  * Put task to the end of the run list without the overhead of dequeue
668  * followed by enqueue.
669  *
670  * Note: We always enqueue the task to the shared-queue, regardless of its
671  * previous position w.r.t. exclusive vs shared.  This is so that exclusive RR
672  * tasks fairly round-robin with all tasks on the runqueue, not just other
673  * exclusive tasks.
674  */
675 static
676 void requeue_rt_entity(struct rt_rq *rt_rq, struct sched_rt_entity *rt_se)
677 {
678         struct rt_prio_array *array = &rt_rq->active;
679
680         list_del_init(&rt_se->run_list);
681         list_add_tail(&rt_se->run_list, array->squeue + rt_se_prio(rt_se));
682 }
683
684 static void requeue_task_rt(struct rq *rq, struct task_struct *p)
685 {
686         struct sched_rt_entity *rt_se = &p->rt;
687         struct rt_rq *rt_rq;
688
689         for_each_sched_rt_entity(rt_se) {
690                 rt_rq = rt_rq_of_se(rt_se);
691                 requeue_rt_entity(rt_rq, rt_se);
692         }
693 }
694
695 static void yield_task_rt(struct rq *rq)
696 {
697         requeue_task_rt(rq, rq->curr);
698 }
699
700 #ifdef CONFIG_SMP
701 static int find_lowest_rq(struct task_struct *task);
702
703 static int select_task_rq_rt(struct task_struct *p, int sync)
704 {
705         struct rq *rq = task_rq(p);
706
707         /*
708          * If the current task is an RT task, then
709          * try to see if we can wake this RT task up on another
710          * runqueue. Otherwise simply start this RT task
711          * on its current runqueue.
712          *
713          * We want to avoid overloading runqueues. Even if
714          * the RT task is of higher priority than the current RT task.
715          * RT tasks behave differently than other tasks. If
716          * one gets preempted, we try to push it off to another queue.
717          * So trying to keep a preempting RT task on the same
718          * cache hot CPU will force the running RT task to
719          * a cold CPU. So we waste all the cache for the lower
720          * RT task in hopes of saving some of a RT task
721          * that is just being woken and probably will have
722          * cold cache anyway.
723          */
724         if (unlikely(rt_task(rq->curr)) &&
725             (p->rt.nr_cpus_allowed > 1)) {
726                 int cpu = find_lowest_rq(p);
727
728                 return (cpu == -1) ? task_cpu(p) : cpu;
729         }
730
731         /*
732          * Otherwise, just let it ride on the affined RQ and the
733          * post-schedule router will push the preempted task away
734          */
735         return task_cpu(p);
736 }
737 #endif /* CONFIG_SMP */
738
739 static struct sched_rt_entity *pick_next_rt_entity(struct rq *rq,
740                                                    struct rt_rq *rt_rq);
741
742 /*
743  * Preempt the current task with a newly woken task if needed:
744  */
745 static void check_preempt_curr_rt(struct rq *rq, struct task_struct *p)
746 {
747         if (p->prio < rq->curr->prio) {
748                 resched_task(rq->curr);
749                 return;
750         }
751
752 #ifdef CONFIG_SMP
753         /*
754          * If:
755          *
756          * - the newly woken task is of equal priority to the current task
757          * - the newly woken task is non-migratable while current is migratable
758          * - current will be preempted on the next reschedule
759          *
760          * we should check to see if current can readily move to a different
761          * cpu.  If so, we will reschedule to allow the push logic to try
762          * to move current somewhere else, making room for our non-migratable
763          * task.
764          */
765         if((p->prio == rq->curr->prio)
766            && p->rt.nr_cpus_allowed == 1
767            && rq->curr->rt.nr_cpus_allowed != 1
768            && pick_next_rt_entity(rq, &rq->rt) != &rq->curr->rt) {
769                 cpumask_t mask;
770
771                 if (cpupri_find(&rq->rd->cpupri, rq->curr, &mask))
772                         /*
773                          * There appears to be other cpus that can accept
774                          * current, so lets reschedule to try and push it away
775                          */
776                         resched_task(rq->curr);
777         }
778 #endif
779 }
780
781 static struct sched_rt_entity *pick_next_rt_entity(struct rq *rq,
782                                                    struct rt_rq *rt_rq)
783 {
784         struct rt_prio_array *array = &rt_rq->active;
785         struct sched_rt_entity *next = NULL;
786         struct list_head *queue;
787         int idx;
788
789         idx = sched_find_first_bit(array->bitmap);
790         BUG_ON(idx >= MAX_RT_PRIO);
791
792         queue = array->xqueue + idx;
793         if (!list_empty(queue))
794                 next = list_entry(queue->next, struct sched_rt_entity,
795                                   run_list);
796         else {
797                 queue = array->squeue + idx;
798                 next = list_entry(queue->next, struct sched_rt_entity,
799                                   run_list);
800         }
801
802         return next;
803 }
804
805 static struct task_struct *pick_next_task_rt(struct rq *rq)
806 {
807         struct sched_rt_entity *rt_se;
808         struct task_struct *p;
809         struct rt_rq *rt_rq;
810
811         rt_rq = &rq->rt;
812
813         if (unlikely(!rt_rq->rt_nr_running))
814                 return NULL;
815
816         if (rt_rq_throttled(rt_rq))
817                 return NULL;
818
819         do {
820                 rt_se = pick_next_rt_entity(rq, rt_rq);
821                 BUG_ON(!rt_se);
822                 rt_rq = group_rt_rq(rt_se);
823         } while (rt_rq);
824
825         p = rt_task_of(rt_se);
826         p->se.exec_start = rq->clock;
827         return p;
828 }
829
830 static void put_prev_task_rt(struct rq *rq, struct task_struct *p)
831 {
832         update_curr_rt(rq);
833         p->se.exec_start = 0;
834 }
835
836 #ifdef CONFIG_SMP
837
838 /* Only try algorithms three times */
839 #define RT_MAX_TRIES 3
840
841 static int double_lock_balance(struct rq *this_rq, struct rq *busiest);
842 static void deactivate_task(struct rq *rq, struct task_struct *p, int sleep);
843
844 static int pick_rt_task(struct rq *rq, struct task_struct *p, int cpu)
845 {
846         if (!task_running(rq, p) &&
847             (cpu < 0 || cpu_isset(cpu, p->cpus_allowed)) &&
848             (p->rt.nr_cpus_allowed > 1))
849                 return 1;
850         return 0;
851 }
852
853 /* Return the second highest RT task, NULL otherwise */
854 static struct task_struct *pick_next_highest_task_rt(struct rq *rq, int cpu)
855 {
856         struct task_struct *next = NULL;
857         struct sched_rt_entity *rt_se;
858         struct rt_prio_array *array;
859         struct rt_rq *rt_rq;
860         int idx;
861
862         for_each_leaf_rt_rq(rt_rq, rq) {
863                 array = &rt_rq->active;
864                 idx = sched_find_first_bit(array->bitmap);
865  next_idx:
866                 if (idx >= MAX_RT_PRIO)
867                         continue;
868                 if (next && next->prio < idx)
869                         continue;
870                 list_for_each_entry(rt_se, array->squeue + idx, run_list) {
871                         struct task_struct *p = rt_task_of(rt_se);
872                         if (pick_rt_task(rq, p, cpu)) {
873                                 next = p;
874                                 break;
875                         }
876                 }
877                 if (!next) {
878                         idx = find_next_bit(array->bitmap, MAX_RT_PRIO, idx+1);
879                         goto next_idx;
880                 }
881         }
882
883         return next;
884 }
885
886 static DEFINE_PER_CPU(cpumask_t, local_cpu_mask);
887
888 static inline int pick_optimal_cpu(int this_cpu, cpumask_t *mask)
889 {
890         int first;
891
892         /* "this_cpu" is cheaper to preempt than a remote processor */
893         if ((this_cpu != -1) && cpu_isset(this_cpu, *mask))
894                 return this_cpu;
895
896         first = first_cpu(*mask);
897         if (first != NR_CPUS)
898                 return first;
899
900         return -1;
901 }
902
903 static int find_lowest_rq(struct task_struct *task)
904 {
905         struct sched_domain *sd;
906         cpumask_t *lowest_mask = &__get_cpu_var(local_cpu_mask);
907         int this_cpu = smp_processor_id();
908         int cpu      = task_cpu(task);
909
910         if (task->rt.nr_cpus_allowed == 1)
911                 return -1; /* No other targets possible */
912
913         if (!cpupri_find(&task_rq(task)->rd->cpupri, task, lowest_mask))
914                 return -1; /* No targets found */
915
916         /*
917          * At this point we have built a mask of cpus representing the
918          * lowest priority tasks in the system.  Now we want to elect
919          * the best one based on our affinity and topology.
920          *
921          * We prioritize the last cpu that the task executed on since
922          * it is most likely cache-hot in that location.
923          */
924         if (cpu_isset(cpu, *lowest_mask))
925                 return cpu;
926
927         /*
928          * Otherwise, we consult the sched_domains span maps to figure
929          * out which cpu is logically closest to our hot cache data.
930          */
931         if (this_cpu == cpu)
932                 this_cpu = -1; /* Skip this_cpu opt if the same */
933
934         for_each_domain(cpu, sd) {
935                 if (sd->flags & SD_WAKE_AFFINE) {
936                         cpumask_t domain_mask;
937                         int       best_cpu;
938
939                         cpus_and(domain_mask, sd->span, *lowest_mask);
940
941                         best_cpu = pick_optimal_cpu(this_cpu,
942                                                     &domain_mask);
943                         if (best_cpu != -1)
944                                 return best_cpu;
945                 }
946         }
947
948         /*
949          * And finally, if there were no matches within the domains
950          * just give the caller *something* to work with from the compatible
951          * locations.
952          */
953         return pick_optimal_cpu(this_cpu, lowest_mask);
954 }
955
956 /* Will lock the rq it finds */
957 static struct rq *find_lock_lowest_rq(struct task_struct *task, struct rq *rq)
958 {
959         struct rq *lowest_rq = NULL;
960         int tries;
961         int cpu;
962
963         for (tries = 0; tries < RT_MAX_TRIES; tries++) {
964                 cpu = find_lowest_rq(task);
965
966                 if ((cpu == -1) || (cpu == rq->cpu))
967                         break;
968
969                 lowest_rq = cpu_rq(cpu);
970
971                 /* if the prio of this runqueue changed, try again */
972                 if (double_lock_balance(rq, lowest_rq)) {
973                         /*
974                          * We had to unlock the run queue. In
975                          * the mean time, task could have
976                          * migrated already or had its affinity changed.
977                          * Also make sure that it wasn't scheduled on its rq.
978                          */
979                         if (unlikely(task_rq(task) != rq ||
980                                      !cpu_isset(lowest_rq->cpu,
981                                                 task->cpus_allowed) ||
982                                      task_running(rq, task) ||
983                                      !task->se.on_rq)) {
984
985                                 spin_unlock(&lowest_rq->lock);
986                                 lowest_rq = NULL;
987                                 break;
988                         }
989                 }
990
991                 /* If this rq is still suitable use it. */
992                 if (lowest_rq->rt.highest_prio > task->prio)
993                         break;
994
995                 /* try again */
996                 spin_unlock(&lowest_rq->lock);
997                 lowest_rq = NULL;
998         }
999
1000         return lowest_rq;
1001 }
1002
1003 /*
1004  * If the current CPU has more than one RT task, see if the non
1005  * running task can migrate over to a CPU that is running a task
1006  * of lesser priority.
1007  */
1008 static int push_rt_task(struct rq *rq)
1009 {
1010         struct task_struct *next_task;
1011         struct rq *lowest_rq;
1012         int ret = 0;
1013         int paranoid = RT_MAX_TRIES;
1014
1015         if (!rq->rt.overloaded)
1016                 return 0;
1017
1018         next_task = pick_next_highest_task_rt(rq, -1);
1019         if (!next_task)
1020                 return 0;
1021
1022  retry:
1023         if (unlikely(next_task == rq->curr)) {
1024                 WARN_ON(1);
1025                 return 0;
1026         }
1027
1028         /*
1029          * It's possible that the next_task slipped in of
1030          * higher priority than current. If that's the case
1031          * just reschedule current.
1032          */
1033         if (unlikely(next_task->prio < rq->curr->prio)) {
1034                 resched_task(rq->curr);
1035                 return 0;
1036         }
1037
1038         /* We might release rq lock */
1039         get_task_struct(next_task);
1040
1041         /* find_lock_lowest_rq locks the rq if found */
1042         lowest_rq = find_lock_lowest_rq(next_task, rq);
1043         if (!lowest_rq) {
1044                 struct task_struct *task;
1045                 /*
1046                  * find lock_lowest_rq releases rq->lock
1047                  * so it is possible that next_task has changed.
1048                  * If it has, then try again.
1049                  */
1050                 task = pick_next_highest_task_rt(rq, -1);
1051                 if (unlikely(task != next_task) && task && paranoid--) {
1052                         put_task_struct(next_task);
1053                         next_task = task;
1054                         goto retry;
1055                 }
1056                 goto out;
1057         }
1058
1059         deactivate_task(rq, next_task, 0);
1060         set_task_cpu(next_task, lowest_rq->cpu);
1061         activate_task(lowest_rq, next_task, 0);
1062
1063         resched_task(lowest_rq->curr);
1064
1065         spin_unlock(&lowest_rq->lock);
1066
1067         ret = 1;
1068 out:
1069         put_task_struct(next_task);
1070
1071         return ret;
1072 }
1073
1074 /*
1075  * TODO: Currently we just use the second highest prio task on
1076  *       the queue, and stop when it can't migrate (or there's
1077  *       no more RT tasks).  There may be a case where a lower
1078  *       priority RT task has a different affinity than the
1079  *       higher RT task. In this case the lower RT task could
1080  *       possibly be able to migrate where as the higher priority
1081  *       RT task could not.  We currently ignore this issue.
1082  *       Enhancements are welcome!
1083  */
1084 static void push_rt_tasks(struct rq *rq)
1085 {
1086         /* push_rt_task will return true if it moved an RT */
1087         while (push_rt_task(rq))
1088                 ;
1089 }
1090
1091 static int pull_rt_task(struct rq *this_rq)
1092 {
1093         int this_cpu = this_rq->cpu, ret = 0, cpu;
1094         struct task_struct *p, *next;
1095         struct rq *src_rq;
1096
1097         if (likely(!rt_overloaded(this_rq)))
1098                 return 0;
1099
1100         next = pick_next_task_rt(this_rq);
1101
1102         for_each_cpu_mask(cpu, this_rq->rd->rto_mask) {
1103                 if (this_cpu == cpu)
1104                         continue;
1105
1106                 src_rq = cpu_rq(cpu);
1107                 /*
1108                  * We can potentially drop this_rq's lock in
1109                  * double_lock_balance, and another CPU could
1110                  * steal our next task - hence we must cause
1111                  * the caller to recalculate the next task
1112                  * in that case:
1113                  */
1114                 if (double_lock_balance(this_rq, src_rq)) {
1115                         struct task_struct *old_next = next;
1116
1117                         next = pick_next_task_rt(this_rq);
1118                         if (next != old_next)
1119                                 ret = 1;
1120                 }
1121
1122                 /*
1123                  * Are there still pullable RT tasks?
1124                  */
1125                 if (src_rq->rt.rt_nr_running <= 1)
1126                         goto skip;
1127
1128                 p = pick_next_highest_task_rt(src_rq, this_cpu);
1129
1130                 /*
1131                  * Do we have an RT task that preempts
1132                  * the to-be-scheduled task?
1133                  */
1134                 if (p && (!next || (p->prio < next->prio))) {
1135                         WARN_ON(p == src_rq->curr);
1136                         WARN_ON(!p->se.on_rq);
1137
1138                         /*
1139                          * There's a chance that p is higher in priority
1140                          * than what's currently running on its cpu.
1141                          * This is just that p is wakeing up and hasn't
1142                          * had a chance to schedule. We only pull
1143                          * p if it is lower in priority than the
1144                          * current task on the run queue or
1145                          * this_rq next task is lower in prio than
1146                          * the current task on that rq.
1147                          */
1148                         if (p->prio < src_rq->curr->prio ||
1149                             (next && next->prio < src_rq->curr->prio))
1150                                 goto skip;
1151
1152                         ret = 1;
1153
1154                         deactivate_task(src_rq, p, 0);
1155                         set_task_cpu(p, this_cpu);
1156                         activate_task(this_rq, p, 0);
1157                         /*
1158                          * We continue with the search, just in
1159                          * case there's an even higher prio task
1160                          * in another runqueue. (low likelyhood
1161                          * but possible)
1162                          *
1163                          * Update next so that we won't pick a task
1164                          * on another cpu with a priority lower (or equal)
1165                          * than the one we just picked.
1166                          */
1167                         next = p;
1168
1169                 }
1170  skip:
1171                 spin_unlock(&src_rq->lock);
1172         }
1173
1174         return ret;
1175 }
1176
1177 static void pre_schedule_rt(struct rq *rq, struct task_struct *prev)
1178 {
1179         /* Try to pull RT tasks here if we lower this rq's prio */
1180         if (unlikely(rt_task(prev)) && rq->rt.highest_prio > prev->prio)
1181                 pull_rt_task(rq);
1182 }
1183
1184 static void post_schedule_rt(struct rq *rq)
1185 {
1186         /*
1187          * If we have more than one rt_task queued, then
1188          * see if we can push the other rt_tasks off to other CPUS.
1189          * Note we may release the rq lock, and since
1190          * the lock was owned by prev, we need to release it
1191          * first via finish_lock_switch and then reaquire it here.
1192          */
1193         if (unlikely(rq->rt.overloaded)) {
1194                 spin_lock_irq(&rq->lock);
1195                 push_rt_tasks(rq);
1196                 spin_unlock_irq(&rq->lock);
1197         }
1198 }
1199
1200 /*
1201  * If we are not running and we are not going to reschedule soon, we should
1202  * try to push tasks away now
1203  */
1204 static void task_wake_up_rt(struct rq *rq, struct task_struct *p)
1205 {
1206         if (!task_running(rq, p) &&
1207             !test_tsk_need_resched(rq->curr) &&
1208             rq->rt.overloaded)
1209                 push_rt_tasks(rq);
1210 }
1211
1212 static unsigned long
1213 load_balance_rt(struct rq *this_rq, int this_cpu, struct rq *busiest,
1214                 unsigned long max_load_move,
1215                 struct sched_domain *sd, enum cpu_idle_type idle,
1216                 int *all_pinned, int *this_best_prio)
1217 {
1218         /* don't touch RT tasks */
1219         return 0;
1220 }
1221
1222 static int
1223 move_one_task_rt(struct rq *this_rq, int this_cpu, struct rq *busiest,
1224                  struct sched_domain *sd, enum cpu_idle_type idle)
1225 {
1226         /* don't touch RT tasks */
1227         return 0;
1228 }
1229
1230 static void set_cpus_allowed_rt(struct task_struct *p,
1231                                 const cpumask_t *new_mask)
1232 {
1233         int weight = cpus_weight(*new_mask);
1234
1235         BUG_ON(!rt_task(p));
1236
1237         /*
1238          * Update the migration status of the RQ if we have an RT task
1239          * which is running AND changing its weight value.
1240          */
1241         if (p->se.on_rq && (weight != p->rt.nr_cpus_allowed)) {
1242                 struct rq *rq = task_rq(p);
1243
1244                 if ((p->rt.nr_cpus_allowed <= 1) && (weight > 1)) {
1245                         rq->rt.rt_nr_migratory++;
1246                 } else if ((p->rt.nr_cpus_allowed > 1) && (weight <= 1)) {
1247                         BUG_ON(!rq->rt.rt_nr_migratory);
1248                         rq->rt.rt_nr_migratory--;
1249                 }
1250
1251                 update_rt_migration(rq);
1252
1253                 if (unlikely(weight == 1 || p->rt.nr_cpus_allowed == 1))
1254                         /*
1255                          * If either the new or old weight is a "1", we need
1256                          * to requeue to properly move between shared and
1257                          * exclusive queues.
1258                          */
1259                         requeue_task_rt(rq, p);
1260         }
1261
1262         p->cpus_allowed    = *new_mask;
1263         p->rt.nr_cpus_allowed = weight;
1264 }
1265
1266 /* Assumes rq->lock is held */
1267 static void rq_online_rt(struct rq *rq)
1268 {
1269         if (rq->rt.overloaded)
1270                 rt_set_overload(rq);
1271
1272         __enable_runtime(rq);
1273
1274         cpupri_set(&rq->rd->cpupri, rq->cpu, rq->rt.highest_prio);
1275 }
1276
1277 /* Assumes rq->lock is held */
1278 static void rq_offline_rt(struct rq *rq)
1279 {
1280         if (rq->rt.overloaded)
1281                 rt_clear_overload(rq);
1282
1283         __disable_runtime(rq);
1284
1285         cpupri_set(&rq->rd->cpupri, rq->cpu, CPUPRI_INVALID);
1286 }
1287
1288 /*
1289  * When switch from the rt queue, we bring ourselves to a position
1290  * that we might want to pull RT tasks from other runqueues.
1291  */
1292 static void switched_from_rt(struct rq *rq, struct task_struct *p,
1293                            int running)
1294 {
1295         /*
1296          * If there are other RT tasks then we will reschedule
1297          * and the scheduling of the other RT tasks will handle
1298          * the balancing. But if we are the last RT task
1299          * we may need to handle the pulling of RT tasks
1300          * now.
1301          */
1302         if (!rq->rt.rt_nr_running)
1303                 pull_rt_task(rq);
1304 }
1305 #endif /* CONFIG_SMP */
1306
1307 /*
1308  * When switching a task to RT, we may overload the runqueue
1309  * with RT tasks. In this case we try to push them off to
1310  * other runqueues.
1311  */
1312 static void switched_to_rt(struct rq *rq, struct task_struct *p,
1313                            int running)
1314 {
1315         int check_resched = 1;
1316
1317         /*
1318          * If we are already running, then there's nothing
1319          * that needs to be done. But if we are not running
1320          * we may need to preempt the current running task.
1321          * If that current running task is also an RT task
1322          * then see if we can move to another run queue.
1323          */
1324         if (!running) {
1325 #ifdef CONFIG_SMP
1326                 if (rq->rt.overloaded && push_rt_task(rq) &&
1327                     /* Don't resched if we changed runqueues */
1328                     rq != task_rq(p))
1329                         check_resched = 0;
1330 #endif /* CONFIG_SMP */
1331                 if (check_resched && p->prio < rq->curr->prio)
1332                         resched_task(rq->curr);
1333         }
1334 }
1335
1336 /*
1337  * Priority of the task has changed. This may cause
1338  * us to initiate a push or pull.
1339  */
1340 static void prio_changed_rt(struct rq *rq, struct task_struct *p,
1341                             int oldprio, int running)
1342 {
1343         if (running) {
1344 #ifdef CONFIG_SMP
1345                 /*
1346                  * If our priority decreases while running, we
1347                  * may need to pull tasks to this runqueue.
1348                  */
1349                 if (oldprio < p->prio)
1350                         pull_rt_task(rq);
1351                 /*
1352                  * If there's a higher priority task waiting to run
1353                  * then reschedule. Note, the above pull_rt_task
1354                  * can release the rq lock and p could migrate.
1355                  * Only reschedule if p is still on the same runqueue.
1356                  */
1357                 if (p->prio > rq->rt.highest_prio && rq->curr == p)
1358                         resched_task(p);
1359 #else
1360                 /* For UP simply resched on drop of prio */
1361                 if (oldprio < p->prio)
1362                         resched_task(p);
1363 #endif /* CONFIG_SMP */
1364         } else {
1365                 /*
1366                  * This task is not running, but if it is
1367                  * greater than the current running task
1368                  * then reschedule.
1369                  */
1370                 if (p->prio < rq->curr->prio)
1371                         resched_task(rq->curr);
1372         }
1373 }
1374
1375 static void watchdog(struct rq *rq, struct task_struct *p)
1376 {
1377         unsigned long soft, hard;
1378
1379         if (!p->signal)
1380                 return;
1381
1382         soft = p->signal->rlim[RLIMIT_RTTIME].rlim_cur;
1383         hard = p->signal->rlim[RLIMIT_RTTIME].rlim_max;
1384
1385         if (soft != RLIM_INFINITY) {
1386                 unsigned long next;
1387
1388                 p->rt.timeout++;
1389                 next = DIV_ROUND_UP(min(soft, hard), USEC_PER_SEC/HZ);
1390                 if (p->rt.timeout > next)
1391                         p->it_sched_expires = p->se.sum_exec_runtime;
1392         }
1393 }
1394
1395 static void task_tick_rt(struct rq *rq, struct task_struct *p, int queued)
1396 {
1397         update_curr_rt(rq);
1398
1399         watchdog(rq, p);
1400
1401         /*
1402          * RR tasks need a special form of timeslice management.
1403          * FIFO tasks have no timeslices.
1404          */
1405         if (p->policy != SCHED_RR)
1406                 return;
1407
1408         if (--p->rt.time_slice)
1409                 return;
1410
1411         p->rt.time_slice = DEF_TIMESLICE;
1412
1413         /*
1414          * Requeue to the end of queue if we are not the only element
1415          * on the queue:
1416          */
1417         if (p->rt.run_list.prev != p->rt.run_list.next) {
1418                 requeue_task_rt(rq, p);
1419                 set_tsk_need_resched(p);
1420         }
1421 }
1422
1423 static void set_curr_task_rt(struct rq *rq)
1424 {
1425         struct task_struct *p = rq->curr;
1426
1427         p->se.exec_start = rq->clock;
1428 }
1429
1430 static const struct sched_class rt_sched_class = {
1431         .next                   = &fair_sched_class,
1432         .enqueue_task           = enqueue_task_rt,
1433         .dequeue_task           = dequeue_task_rt,
1434         .yield_task             = yield_task_rt,
1435 #ifdef CONFIG_SMP
1436         .select_task_rq         = select_task_rq_rt,
1437 #endif /* CONFIG_SMP */
1438
1439         .check_preempt_curr     = check_preempt_curr_rt,
1440
1441         .pick_next_task         = pick_next_task_rt,
1442         .put_prev_task          = put_prev_task_rt,
1443
1444 #ifdef CONFIG_SMP
1445         .load_balance           = load_balance_rt,
1446         .move_one_task          = move_one_task_rt,
1447         .set_cpus_allowed       = set_cpus_allowed_rt,
1448         .rq_online              = rq_online_rt,
1449         .rq_offline             = rq_offline_rt,
1450         .pre_schedule           = pre_schedule_rt,
1451         .post_schedule          = post_schedule_rt,
1452         .task_wake_up           = task_wake_up_rt,
1453         .switched_from          = switched_from_rt,
1454 #endif
1455
1456         .set_curr_task          = set_curr_task_rt,
1457         .task_tick              = task_tick_rt,
1458
1459         .prio_changed           = prio_changed_rt,
1460         .switched_to            = switched_to_rt,
1461 };