2 * Real-Time Scheduling Class (mapped to the SCHED_FIFO and SCHED_RR
6 #ifdef CONFIG_RT_GROUP_SCHED
8 #define rt_entity_is_task(rt_se) (!(rt_se)->my_q)
10 static inline struct task_struct *rt_task_of(struct sched_rt_entity *rt_se)
12 #ifdef CONFIG_SCHED_DEBUG
13 WARN_ON_ONCE(!rt_entity_is_task(rt_se));
15 return container_of(rt_se, struct task_struct, rt);
18 static inline struct rq *rq_of_rt_rq(struct rt_rq *rt_rq)
23 static inline struct rt_rq *rt_rq_of_se(struct sched_rt_entity *rt_se)
28 #else /* CONFIG_RT_GROUP_SCHED */
30 #define rt_entity_is_task(rt_se) (1)
32 static inline struct task_struct *rt_task_of(struct sched_rt_entity *rt_se)
34 return container_of(rt_se, struct task_struct, rt);
37 static inline struct rq *rq_of_rt_rq(struct rt_rq *rt_rq)
39 return container_of(rt_rq, struct rq, rt);
42 static inline struct rt_rq *rt_rq_of_se(struct sched_rt_entity *rt_se)
44 struct task_struct *p = rt_task_of(rt_se);
45 struct rq *rq = task_rq(p);
50 #endif /* CONFIG_RT_GROUP_SCHED */
54 static inline int rt_overloaded(struct rq *rq)
56 return atomic_read(&rq->rd->rto_count);
59 static inline void rt_set_overload(struct rq *rq)
64 cpumask_set_cpu(rq->cpu, rq->rd->rto_mask);
66 * Make sure the mask is visible before we set
67 * the overload count. That is checked to determine
68 * if we should look at the mask. It would be a shame
69 * if we looked at the mask, but the mask was not
73 atomic_inc(&rq->rd->rto_count);
76 static inline void rt_clear_overload(struct rq *rq)
81 /* the order here really doesn't matter */
82 atomic_dec(&rq->rd->rto_count);
83 cpumask_clear_cpu(rq->cpu, rq->rd->rto_mask);
86 static void update_rt_migration(struct rt_rq *rt_rq)
88 if (rt_rq->rt_nr_migratory && rt_rq->rt_nr_total > 1) {
89 if (!rt_rq->overloaded) {
90 rt_set_overload(rq_of_rt_rq(rt_rq));
91 rt_rq->overloaded = 1;
93 } else if (rt_rq->overloaded) {
94 rt_clear_overload(rq_of_rt_rq(rt_rq));
95 rt_rq->overloaded = 0;
99 static void inc_rt_migration(struct sched_rt_entity *rt_se, struct rt_rq *rt_rq)
101 if (!rt_entity_is_task(rt_se))
104 rt_rq = &rq_of_rt_rq(rt_rq)->rt;
106 rt_rq->rt_nr_total++;
107 if (rt_se->nr_cpus_allowed > 1)
108 rt_rq->rt_nr_migratory++;
110 update_rt_migration(rt_rq);
113 static void dec_rt_migration(struct sched_rt_entity *rt_se, struct rt_rq *rt_rq)
115 if (!rt_entity_is_task(rt_se))
118 rt_rq = &rq_of_rt_rq(rt_rq)->rt;
120 rt_rq->rt_nr_total--;
121 if (rt_se->nr_cpus_allowed > 1)
122 rt_rq->rt_nr_migratory--;
124 update_rt_migration(rt_rq);
127 static inline int has_pushable_tasks(struct rq *rq)
129 return !plist_head_empty(&rq->rt.pushable_tasks);
132 static void enqueue_pushable_task(struct rq *rq, struct task_struct *p)
134 plist_del(&p->pushable_tasks, &rq->rt.pushable_tasks);
135 plist_node_init(&p->pushable_tasks, p->prio);
136 plist_add(&p->pushable_tasks, &rq->rt.pushable_tasks);
138 /* Update the highest prio pushable task */
139 if (p->prio < rq->rt.highest_prio.next)
140 rq->rt.highest_prio.next = p->prio;
143 static void dequeue_pushable_task(struct rq *rq, struct task_struct *p)
145 plist_del(&p->pushable_tasks, &rq->rt.pushable_tasks);
147 /* Update the new highest prio pushable task */
148 if (has_pushable_tasks(rq)) {
149 p = plist_first_entry(&rq->rt.pushable_tasks,
150 struct task_struct, pushable_tasks);
151 rq->rt.highest_prio.next = p->prio;
153 rq->rt.highest_prio.next = MAX_RT_PRIO;
158 static inline void enqueue_pushable_task(struct rq *rq, struct task_struct *p)
162 static inline void dequeue_pushable_task(struct rq *rq, struct task_struct *p)
167 void inc_rt_migration(struct sched_rt_entity *rt_se, struct rt_rq *rt_rq)
172 void dec_rt_migration(struct sched_rt_entity *rt_se, struct rt_rq *rt_rq)
176 #endif /* CONFIG_SMP */
178 static inline int on_rt_rq(struct sched_rt_entity *rt_se)
180 return !list_empty(&rt_se->run_list);
183 #ifdef CONFIG_RT_GROUP_SCHED
185 static inline u64 sched_rt_runtime(struct rt_rq *rt_rq)
190 return rt_rq->rt_runtime;
193 static inline u64 sched_rt_period(struct rt_rq *rt_rq)
195 return ktime_to_ns(rt_rq->tg->rt_bandwidth.rt_period);
198 typedef struct task_group *rt_rq_iter_t;
200 static inline struct task_group *next_task_group(struct task_group *tg)
203 tg = list_entry_rcu(tg->list.next,
204 typeof(struct task_group), list);
205 } while (&tg->list != &task_groups && task_group_is_autogroup(tg));
207 if (&tg->list == &task_groups)
213 #define for_each_rt_rq(rt_rq, iter, rq) \
214 for (iter = container_of(&task_groups, typeof(*iter), list); \
215 (iter = next_task_group(iter)) && \
216 (rt_rq = iter->rt_rq[cpu_of(rq)]);)
218 static inline void list_add_leaf_rt_rq(struct rt_rq *rt_rq)
220 list_add_rcu(&rt_rq->leaf_rt_rq_list,
221 &rq_of_rt_rq(rt_rq)->leaf_rt_rq_list);
224 static inline void list_del_leaf_rt_rq(struct rt_rq *rt_rq)
226 list_del_rcu(&rt_rq->leaf_rt_rq_list);
229 #define for_each_leaf_rt_rq(rt_rq, rq) \
230 list_for_each_entry_rcu(rt_rq, &rq->leaf_rt_rq_list, leaf_rt_rq_list)
232 #define for_each_sched_rt_entity(rt_se) \
233 for (; rt_se; rt_se = rt_se->parent)
235 static inline struct rt_rq *group_rt_rq(struct sched_rt_entity *rt_se)
240 static void enqueue_rt_entity(struct sched_rt_entity *rt_se, bool head);
241 static void dequeue_rt_entity(struct sched_rt_entity *rt_se);
243 static void sched_rt_rq_enqueue(struct rt_rq *rt_rq)
245 struct task_struct *curr = rq_of_rt_rq(rt_rq)->curr;
246 struct sched_rt_entity *rt_se;
248 int cpu = cpu_of(rq_of_rt_rq(rt_rq));
250 rt_se = rt_rq->tg->rt_se[cpu];
252 if (rt_rq->rt_nr_running) {
253 if (rt_se && !on_rt_rq(rt_se))
254 enqueue_rt_entity(rt_se, false);
255 if (rt_rq->highest_prio.curr < curr->prio)
260 static void sched_rt_rq_dequeue(struct rt_rq *rt_rq)
262 struct sched_rt_entity *rt_se;
263 int cpu = cpu_of(rq_of_rt_rq(rt_rq));
265 rt_se = rt_rq->tg->rt_se[cpu];
267 if (rt_se && on_rt_rq(rt_se))
268 dequeue_rt_entity(rt_se);
271 static inline int rt_rq_throttled(struct rt_rq *rt_rq)
273 return rt_rq->rt_throttled && !rt_rq->rt_nr_boosted;
276 static int rt_se_boosted(struct sched_rt_entity *rt_se)
278 struct rt_rq *rt_rq = group_rt_rq(rt_se);
279 struct task_struct *p;
282 return !!rt_rq->rt_nr_boosted;
284 p = rt_task_of(rt_se);
285 return p->prio != p->normal_prio;
289 static inline const struct cpumask *sched_rt_period_mask(void)
291 return cpu_rq(smp_processor_id())->rd->span;
294 static inline const struct cpumask *sched_rt_period_mask(void)
296 return cpu_online_mask;
301 struct rt_rq *sched_rt_period_rt_rq(struct rt_bandwidth *rt_b, int cpu)
303 return container_of(rt_b, struct task_group, rt_bandwidth)->rt_rq[cpu];
306 static inline struct rt_bandwidth *sched_rt_bandwidth(struct rt_rq *rt_rq)
308 return &rt_rq->tg->rt_bandwidth;
311 #else /* !CONFIG_RT_GROUP_SCHED */
313 static inline u64 sched_rt_runtime(struct rt_rq *rt_rq)
315 return rt_rq->rt_runtime;
318 static inline u64 sched_rt_period(struct rt_rq *rt_rq)
320 return ktime_to_ns(def_rt_bandwidth.rt_period);
323 typedef struct rt_rq *rt_rq_iter_t;
325 #define for_each_rt_rq(rt_rq, iter, rq) \
326 for ((void) iter, rt_rq = &rq->rt; rt_rq; rt_rq = NULL)
328 static inline void list_add_leaf_rt_rq(struct rt_rq *rt_rq)
332 static inline void list_del_leaf_rt_rq(struct rt_rq *rt_rq)
336 #define for_each_leaf_rt_rq(rt_rq, rq) \
337 for (rt_rq = &rq->rt; rt_rq; rt_rq = NULL)
339 #define for_each_sched_rt_entity(rt_se) \
340 for (; rt_se; rt_se = NULL)
342 static inline struct rt_rq *group_rt_rq(struct sched_rt_entity *rt_se)
347 static inline void sched_rt_rq_enqueue(struct rt_rq *rt_rq)
349 if (rt_rq->rt_nr_running)
350 resched_task(rq_of_rt_rq(rt_rq)->curr);
353 static inline void sched_rt_rq_dequeue(struct rt_rq *rt_rq)
357 static inline int rt_rq_throttled(struct rt_rq *rt_rq)
359 return rt_rq->rt_throttled;
362 static inline const struct cpumask *sched_rt_period_mask(void)
364 return cpu_online_mask;
368 struct rt_rq *sched_rt_period_rt_rq(struct rt_bandwidth *rt_b, int cpu)
370 return &cpu_rq(cpu)->rt;
373 static inline struct rt_bandwidth *sched_rt_bandwidth(struct rt_rq *rt_rq)
375 return &def_rt_bandwidth;
378 #endif /* CONFIG_RT_GROUP_SCHED */
382 * We ran out of runtime, see if we can borrow some from our neighbours.
384 static int do_balance_runtime(struct rt_rq *rt_rq)
386 struct rt_bandwidth *rt_b = sched_rt_bandwidth(rt_rq);
387 struct root_domain *rd = cpu_rq(smp_processor_id())->rd;
388 int i, weight, more = 0;
391 weight = cpumask_weight(rd->span);
393 raw_spin_lock(&rt_b->rt_runtime_lock);
394 rt_period = ktime_to_ns(rt_b->rt_period);
395 for_each_cpu(i, rd->span) {
396 struct rt_rq *iter = sched_rt_period_rt_rq(rt_b, i);
402 raw_spin_lock(&iter->rt_runtime_lock);
404 * Either all rqs have inf runtime and there's nothing to steal
405 * or __disable_runtime() below sets a specific rq to inf to
406 * indicate its been disabled and disalow stealing.
408 if (iter->rt_runtime == RUNTIME_INF)
412 * From runqueues with spare time, take 1/n part of their
413 * spare time, but no more than our period.
415 diff = iter->rt_runtime - iter->rt_time;
417 diff = div_u64((u64)diff, weight);
418 if (rt_rq->rt_runtime + diff > rt_period)
419 diff = rt_period - rt_rq->rt_runtime;
420 iter->rt_runtime -= diff;
421 rt_rq->rt_runtime += diff;
423 if (rt_rq->rt_runtime == rt_period) {
424 raw_spin_unlock(&iter->rt_runtime_lock);
429 raw_spin_unlock(&iter->rt_runtime_lock);
431 raw_spin_unlock(&rt_b->rt_runtime_lock);
437 * Ensure this RQ takes back all the runtime it lend to its neighbours.
439 static void __disable_runtime(struct rq *rq)
441 struct root_domain *rd = rq->rd;
445 if (unlikely(!scheduler_running))
448 for_each_rt_rq(rt_rq, iter, rq) {
449 struct rt_bandwidth *rt_b = sched_rt_bandwidth(rt_rq);
453 raw_spin_lock(&rt_b->rt_runtime_lock);
454 raw_spin_lock(&rt_rq->rt_runtime_lock);
456 * Either we're all inf and nobody needs to borrow, or we're
457 * already disabled and thus have nothing to do, or we have
458 * exactly the right amount of runtime to take out.
460 if (rt_rq->rt_runtime == RUNTIME_INF ||
461 rt_rq->rt_runtime == rt_b->rt_runtime)
463 raw_spin_unlock(&rt_rq->rt_runtime_lock);
466 * Calculate the difference between what we started out with
467 * and what we current have, that's the amount of runtime
468 * we lend and now have to reclaim.
470 want = rt_b->rt_runtime - rt_rq->rt_runtime;
473 * Greedy reclaim, take back as much as we can.
475 for_each_cpu(i, rd->span) {
476 struct rt_rq *iter = sched_rt_period_rt_rq(rt_b, i);
480 * Can't reclaim from ourselves or disabled runqueues.
482 if (iter == rt_rq || iter->rt_runtime == RUNTIME_INF)
485 raw_spin_lock(&iter->rt_runtime_lock);
487 diff = min_t(s64, iter->rt_runtime, want);
488 iter->rt_runtime -= diff;
491 iter->rt_runtime -= want;
494 raw_spin_unlock(&iter->rt_runtime_lock);
500 raw_spin_lock(&rt_rq->rt_runtime_lock);
502 * We cannot be left wanting - that would mean some runtime
503 * leaked out of the system.
508 * Disable all the borrow logic by pretending we have inf
509 * runtime - in which case borrowing doesn't make sense.
511 rt_rq->rt_runtime = RUNTIME_INF;
512 raw_spin_unlock(&rt_rq->rt_runtime_lock);
513 raw_spin_unlock(&rt_b->rt_runtime_lock);
517 static void disable_runtime(struct rq *rq)
521 raw_spin_lock_irqsave(&rq->lock, flags);
522 __disable_runtime(rq);
523 raw_spin_unlock_irqrestore(&rq->lock, flags);
526 static void __enable_runtime(struct rq *rq)
531 if (unlikely(!scheduler_running))
535 * Reset each runqueue's bandwidth settings
537 for_each_rt_rq(rt_rq, iter, rq) {
538 struct rt_bandwidth *rt_b = sched_rt_bandwidth(rt_rq);
540 raw_spin_lock(&rt_b->rt_runtime_lock);
541 raw_spin_lock(&rt_rq->rt_runtime_lock);
542 rt_rq->rt_runtime = rt_b->rt_runtime;
544 rt_rq->rt_throttled = 0;
545 raw_spin_unlock(&rt_rq->rt_runtime_lock);
546 raw_spin_unlock(&rt_b->rt_runtime_lock);
550 static void enable_runtime(struct rq *rq)
554 raw_spin_lock_irqsave(&rq->lock, flags);
555 __enable_runtime(rq);
556 raw_spin_unlock_irqrestore(&rq->lock, flags);
559 static int balance_runtime(struct rt_rq *rt_rq)
563 if (rt_rq->rt_time > rt_rq->rt_runtime) {
564 raw_spin_unlock(&rt_rq->rt_runtime_lock);
565 more = do_balance_runtime(rt_rq);
566 raw_spin_lock(&rt_rq->rt_runtime_lock);
571 #else /* !CONFIG_SMP */
572 static inline int balance_runtime(struct rt_rq *rt_rq)
576 #endif /* CONFIG_SMP */
578 static int do_sched_rt_period_timer(struct rt_bandwidth *rt_b, int overrun)
581 const struct cpumask *span;
583 if (!rt_bandwidth_enabled() || rt_b->rt_runtime == RUNTIME_INF)
586 span = sched_rt_period_mask();
587 for_each_cpu(i, span) {
589 struct rt_rq *rt_rq = sched_rt_period_rt_rq(rt_b, i);
590 struct rq *rq = rq_of_rt_rq(rt_rq);
592 raw_spin_lock(&rq->lock);
593 if (rt_rq->rt_time) {
596 raw_spin_lock(&rt_rq->rt_runtime_lock);
597 if (rt_rq->rt_throttled)
598 balance_runtime(rt_rq);
599 runtime = rt_rq->rt_runtime;
600 rt_rq->rt_time -= min(rt_rq->rt_time, overrun*runtime);
601 if (rt_rq->rt_throttled && rt_rq->rt_time < runtime) {
602 rt_rq->rt_throttled = 0;
606 * Force a clock update if the CPU was idle,
607 * lest wakeup -> unthrottle time accumulate.
609 if (rt_rq->rt_nr_running && rq->curr == rq->idle)
610 rq->skip_clock_update = -1;
612 if (rt_rq->rt_time || rt_rq->rt_nr_running)
614 raw_spin_unlock(&rt_rq->rt_runtime_lock);
615 } else if (rt_rq->rt_nr_running) {
617 if (!rt_rq_throttled(rt_rq))
622 sched_rt_rq_enqueue(rt_rq);
623 raw_spin_unlock(&rq->lock);
629 static inline int rt_se_prio(struct sched_rt_entity *rt_se)
631 #ifdef CONFIG_RT_GROUP_SCHED
632 struct rt_rq *rt_rq = group_rt_rq(rt_se);
635 return rt_rq->highest_prio.curr;
638 return rt_task_of(rt_se)->prio;
641 static int sched_rt_runtime_exceeded(struct rt_rq *rt_rq)
643 u64 runtime = sched_rt_runtime(rt_rq);
645 if (rt_rq->rt_throttled)
646 return rt_rq_throttled(rt_rq);
648 if (sched_rt_runtime(rt_rq) >= sched_rt_period(rt_rq))
651 balance_runtime(rt_rq);
652 runtime = sched_rt_runtime(rt_rq);
653 if (runtime == RUNTIME_INF)
656 if (rt_rq->rt_time > runtime) {
657 rt_rq->rt_throttled = 1;
658 if (rt_rq_throttled(rt_rq)) {
659 sched_rt_rq_dequeue(rt_rq);
668 * Update the current task's runtime statistics. Skip current tasks that
669 * are not in our scheduling class.
671 static void update_curr_rt(struct rq *rq)
673 struct task_struct *curr = rq->curr;
674 struct sched_rt_entity *rt_se = &curr->rt;
675 struct rt_rq *rt_rq = rt_rq_of_se(rt_se);
678 if (curr->sched_class != &rt_sched_class)
681 delta_exec = rq->clock_task - curr->se.exec_start;
682 if (unlikely((s64)delta_exec < 0))
685 schedstat_set(curr->se.statistics.exec_max, max(curr->se.statistics.exec_max, delta_exec));
687 curr->se.sum_exec_runtime += delta_exec;
688 account_group_exec_runtime(curr, delta_exec);
690 curr->se.exec_start = rq->clock_task;
691 cpuacct_charge(curr, delta_exec);
693 sched_rt_avg_update(rq, delta_exec);
695 if (!rt_bandwidth_enabled())
698 for_each_sched_rt_entity(rt_se) {
699 rt_rq = rt_rq_of_se(rt_se);
701 if (sched_rt_runtime(rt_rq) != RUNTIME_INF) {
702 raw_spin_lock(&rt_rq->rt_runtime_lock);
703 rt_rq->rt_time += delta_exec;
704 if (sched_rt_runtime_exceeded(rt_rq))
706 raw_spin_unlock(&rt_rq->rt_runtime_lock);
711 #if defined CONFIG_SMP
714 inc_rt_prio_smp(struct rt_rq *rt_rq, int prio, int prev_prio)
716 struct rq *rq = rq_of_rt_rq(rt_rq);
718 if (rq->online && prio < prev_prio)
719 cpupri_set(&rq->rd->cpupri, rq->cpu, prio);
723 dec_rt_prio_smp(struct rt_rq *rt_rq, int prio, int prev_prio)
725 struct rq *rq = rq_of_rt_rq(rt_rq);
727 if (rq->online && rt_rq->highest_prio.curr != prev_prio)
728 cpupri_set(&rq->rd->cpupri, rq->cpu, rt_rq->highest_prio.curr);
731 #else /* CONFIG_SMP */
734 void inc_rt_prio_smp(struct rt_rq *rt_rq, int prio, int prev_prio) {}
736 void dec_rt_prio_smp(struct rt_rq *rt_rq, int prio, int prev_prio) {}
738 #endif /* CONFIG_SMP */
740 #if defined CONFIG_SMP || defined CONFIG_RT_GROUP_SCHED
742 inc_rt_prio(struct rt_rq *rt_rq, int prio)
744 int prev_prio = rt_rq->highest_prio.curr;
746 if (prio < prev_prio)
747 rt_rq->highest_prio.curr = prio;
749 inc_rt_prio_smp(rt_rq, prio, prev_prio);
753 dec_rt_prio(struct rt_rq *rt_rq, int prio)
755 int prev_prio = rt_rq->highest_prio.curr;
757 if (rt_rq->rt_nr_running) {
759 WARN_ON(prio < prev_prio);
762 * This may have been our highest task, and therefore
763 * we may have some recomputation to do
765 if (prio == prev_prio) {
766 struct rt_prio_array *array = &rt_rq->active;
768 rt_rq->highest_prio.curr =
769 sched_find_first_bit(array->bitmap);
773 rt_rq->highest_prio.curr = MAX_RT_PRIO;
775 dec_rt_prio_smp(rt_rq, prio, prev_prio);
780 static inline void inc_rt_prio(struct rt_rq *rt_rq, int prio) {}
781 static inline void dec_rt_prio(struct rt_rq *rt_rq, int prio) {}
783 #endif /* CONFIG_SMP || CONFIG_RT_GROUP_SCHED */
785 #ifdef CONFIG_RT_GROUP_SCHED
788 inc_rt_group(struct sched_rt_entity *rt_se, struct rt_rq *rt_rq)
790 if (rt_se_boosted(rt_se))
791 rt_rq->rt_nr_boosted++;
794 start_rt_bandwidth(&rt_rq->tg->rt_bandwidth);
798 dec_rt_group(struct sched_rt_entity *rt_se, struct rt_rq *rt_rq)
800 if (rt_se_boosted(rt_se))
801 rt_rq->rt_nr_boosted--;
803 WARN_ON(!rt_rq->rt_nr_running && rt_rq->rt_nr_boosted);
806 #else /* CONFIG_RT_GROUP_SCHED */
809 inc_rt_group(struct sched_rt_entity *rt_se, struct rt_rq *rt_rq)
811 start_rt_bandwidth(&def_rt_bandwidth);
815 void dec_rt_group(struct sched_rt_entity *rt_se, struct rt_rq *rt_rq) {}
817 #endif /* CONFIG_RT_GROUP_SCHED */
820 void inc_rt_tasks(struct sched_rt_entity *rt_se, struct rt_rq *rt_rq)
822 int prio = rt_se_prio(rt_se);
824 WARN_ON(!rt_prio(prio));
825 rt_rq->rt_nr_running++;
827 inc_rt_prio(rt_rq, prio);
828 inc_rt_migration(rt_se, rt_rq);
829 inc_rt_group(rt_se, rt_rq);
833 void dec_rt_tasks(struct sched_rt_entity *rt_se, struct rt_rq *rt_rq)
835 WARN_ON(!rt_prio(rt_se_prio(rt_se)));
836 WARN_ON(!rt_rq->rt_nr_running);
837 rt_rq->rt_nr_running--;
839 dec_rt_prio(rt_rq, rt_se_prio(rt_se));
840 dec_rt_migration(rt_se, rt_rq);
841 dec_rt_group(rt_se, rt_rq);
844 static void __enqueue_rt_entity(struct sched_rt_entity *rt_se, bool head)
846 struct rt_rq *rt_rq = rt_rq_of_se(rt_se);
847 struct rt_prio_array *array = &rt_rq->active;
848 struct rt_rq *group_rq = group_rt_rq(rt_se);
849 struct list_head *queue = array->queue + rt_se_prio(rt_se);
852 * Don't enqueue the group if its throttled, or when empty.
853 * The latter is a consequence of the former when a child group
854 * get throttled and the current group doesn't have any other
857 if (group_rq && (rt_rq_throttled(group_rq) || !group_rq->rt_nr_running))
860 if (!rt_rq->rt_nr_running)
861 list_add_leaf_rt_rq(rt_rq);
864 list_add(&rt_se->run_list, queue);
866 list_add_tail(&rt_se->run_list, queue);
867 __set_bit(rt_se_prio(rt_se), array->bitmap);
869 inc_rt_tasks(rt_se, rt_rq);
872 static void __dequeue_rt_entity(struct sched_rt_entity *rt_se)
874 struct rt_rq *rt_rq = rt_rq_of_se(rt_se);
875 struct rt_prio_array *array = &rt_rq->active;
877 list_del_init(&rt_se->run_list);
878 if (list_empty(array->queue + rt_se_prio(rt_se)))
879 __clear_bit(rt_se_prio(rt_se), array->bitmap);
881 dec_rt_tasks(rt_se, rt_rq);
882 if (!rt_rq->rt_nr_running)
883 list_del_leaf_rt_rq(rt_rq);
887 * Because the prio of an upper entry depends on the lower
888 * entries, we must remove entries top - down.
890 static void dequeue_rt_stack(struct sched_rt_entity *rt_se)
892 struct sched_rt_entity *back = NULL;
894 for_each_sched_rt_entity(rt_se) {
899 for (rt_se = back; rt_se; rt_se = rt_se->back) {
901 __dequeue_rt_entity(rt_se);
905 static void enqueue_rt_entity(struct sched_rt_entity *rt_se, bool head)
907 dequeue_rt_stack(rt_se);
908 for_each_sched_rt_entity(rt_se)
909 __enqueue_rt_entity(rt_se, head);
912 static void dequeue_rt_entity(struct sched_rt_entity *rt_se)
914 dequeue_rt_stack(rt_se);
916 for_each_sched_rt_entity(rt_se) {
917 struct rt_rq *rt_rq = group_rt_rq(rt_se);
919 if (rt_rq && rt_rq->rt_nr_running)
920 __enqueue_rt_entity(rt_se, false);
925 * Adding/removing a task to/from a priority array:
928 enqueue_task_rt(struct rq *rq, struct task_struct *p, int flags)
930 struct sched_rt_entity *rt_se = &p->rt;
932 if (flags & ENQUEUE_WAKEUP)
935 enqueue_rt_entity(rt_se, flags & ENQUEUE_HEAD);
937 if (!task_current(rq, p) && p->rt.nr_cpus_allowed > 1)
938 enqueue_pushable_task(rq, p);
943 static void dequeue_task_rt(struct rq *rq, struct task_struct *p, int flags)
945 struct sched_rt_entity *rt_se = &p->rt;
948 dequeue_rt_entity(rt_se);
950 dequeue_pushable_task(rq, p);
956 * Put task to the end of the run list without the overhead of dequeue
957 * followed by enqueue.
960 requeue_rt_entity(struct rt_rq *rt_rq, struct sched_rt_entity *rt_se, int head)
962 if (on_rt_rq(rt_se)) {
963 struct rt_prio_array *array = &rt_rq->active;
964 struct list_head *queue = array->queue + rt_se_prio(rt_se);
967 list_move(&rt_se->run_list, queue);
969 list_move_tail(&rt_se->run_list, queue);
973 static void requeue_task_rt(struct rq *rq, struct task_struct *p, int head)
975 struct sched_rt_entity *rt_se = &p->rt;
978 for_each_sched_rt_entity(rt_se) {
979 rt_rq = rt_rq_of_se(rt_se);
980 requeue_rt_entity(rt_rq, rt_se, head);
984 static void yield_task_rt(struct rq *rq)
986 requeue_task_rt(rq, rq->curr, 0);
990 static int find_lowest_rq(struct task_struct *task);
993 select_task_rq_rt(struct task_struct *p, int sd_flag, int flags)
995 struct task_struct *curr;
1001 /* For anything but wake ups, just return the task_cpu */
1002 if (sd_flag != SD_BALANCE_WAKE && sd_flag != SD_BALANCE_FORK)
1008 curr = ACCESS_ONCE(rq->curr); /* unlocked access */
1011 * If the current task on @p's runqueue is an RT task, then
1012 * try to see if we can wake this RT task up on another
1013 * runqueue. Otherwise simply start this RT task
1014 * on its current runqueue.
1016 * We want to avoid overloading runqueues. If the woken
1017 * task is a higher priority, then it will stay on this CPU
1018 * and the lower prio task should be moved to another CPU.
1019 * Even though this will probably make the lower prio task
1020 * lose its cache, we do not want to bounce a higher task
1021 * around just because it gave up its CPU, perhaps for a
1024 * For equal prio tasks, we just let the scheduler sort it out.
1026 * Otherwise, just let it ride on the affined RQ and the
1027 * post-schedule router will push the preempted task away
1029 * This test is optimistic, if we get it wrong the load-balancer
1030 * will have to sort it out.
1032 if (curr && unlikely(rt_task(curr)) &&
1033 (curr->rt.nr_cpus_allowed < 2 ||
1034 curr->prio <= p->prio) &&
1035 (p->rt.nr_cpus_allowed > 1)) {
1036 int target = find_lowest_rq(p);
1047 static void check_preempt_equal_prio(struct rq *rq, struct task_struct *p)
1049 if (rq->curr->rt.nr_cpus_allowed == 1)
1052 if (p->rt.nr_cpus_allowed != 1
1053 && cpupri_find(&rq->rd->cpupri, p, NULL))
1056 if (!cpupri_find(&rq->rd->cpupri, rq->curr, NULL))
1060 * There appears to be other cpus that can accept
1061 * current and none to run 'p', so lets reschedule
1062 * to try and push current away:
1064 requeue_task_rt(rq, p, 1);
1065 resched_task(rq->curr);
1068 #endif /* CONFIG_SMP */
1071 * Preempt the current task with a newly woken task if needed:
1073 static void check_preempt_curr_rt(struct rq *rq, struct task_struct *p, int flags)
1075 if (p->prio < rq->curr->prio) {
1076 resched_task(rq->curr);
1084 * - the newly woken task is of equal priority to the current task
1085 * - the newly woken task is non-migratable while current is migratable
1086 * - current will be preempted on the next reschedule
1088 * we should check to see if current can readily move to a different
1089 * cpu. If so, we will reschedule to allow the push logic to try
1090 * to move current somewhere else, making room for our non-migratable
1093 if (p->prio == rq->curr->prio && !test_tsk_need_resched(rq->curr))
1094 check_preempt_equal_prio(rq, p);
1098 static struct sched_rt_entity *pick_next_rt_entity(struct rq *rq,
1099 struct rt_rq *rt_rq)
1101 struct rt_prio_array *array = &rt_rq->active;
1102 struct sched_rt_entity *next = NULL;
1103 struct list_head *queue;
1106 idx = sched_find_first_bit(array->bitmap);
1107 BUG_ON(idx >= MAX_RT_PRIO);
1109 queue = array->queue + idx;
1110 next = list_entry(queue->next, struct sched_rt_entity, run_list);
1115 static struct task_struct *_pick_next_task_rt(struct rq *rq)
1117 struct sched_rt_entity *rt_se;
1118 struct task_struct *p;
1119 struct rt_rq *rt_rq;
1123 if (!rt_rq->rt_nr_running)
1126 if (rt_rq_throttled(rt_rq))
1130 rt_se = pick_next_rt_entity(rq, rt_rq);
1132 rt_rq = group_rt_rq(rt_se);
1135 p = rt_task_of(rt_se);
1136 p->se.exec_start = rq->clock_task;
1141 static struct task_struct *pick_next_task_rt(struct rq *rq)
1143 struct task_struct *p = _pick_next_task_rt(rq);
1145 /* The running task is never eligible for pushing */
1147 dequeue_pushable_task(rq, p);
1151 * We detect this state here so that we can avoid taking the RQ
1152 * lock again later if there is no need to push
1154 rq->post_schedule = has_pushable_tasks(rq);
1160 static void put_prev_task_rt(struct rq *rq, struct task_struct *p)
1165 * The previous task needs to be made eligible for pushing
1166 * if it is still active
1168 if (on_rt_rq(&p->rt) && p->rt.nr_cpus_allowed > 1)
1169 enqueue_pushable_task(rq, p);
1174 /* Only try algorithms three times */
1175 #define RT_MAX_TRIES 3
1177 static void deactivate_task(struct rq *rq, struct task_struct *p, int sleep);
1179 static int pick_rt_task(struct rq *rq, struct task_struct *p, int cpu)
1181 if (!task_running(rq, p) &&
1182 (cpu < 0 || cpumask_test_cpu(cpu, tsk_cpus_allowed(p))) &&
1183 (p->rt.nr_cpus_allowed > 1))
1188 /* Return the second highest RT task, NULL otherwise */
1189 static struct task_struct *pick_next_highest_task_rt(struct rq *rq, int cpu)
1191 struct task_struct *next = NULL;
1192 struct sched_rt_entity *rt_se;
1193 struct rt_prio_array *array;
1194 struct rt_rq *rt_rq;
1197 for_each_leaf_rt_rq(rt_rq, rq) {
1198 array = &rt_rq->active;
1199 idx = sched_find_first_bit(array->bitmap);
1201 if (idx >= MAX_RT_PRIO)
1203 if (next && next->prio < idx)
1205 list_for_each_entry(rt_se, array->queue + idx, run_list) {
1206 struct task_struct *p;
1208 if (!rt_entity_is_task(rt_se))
1211 p = rt_task_of(rt_se);
1212 if (pick_rt_task(rq, p, cpu)) {
1218 idx = find_next_bit(array->bitmap, MAX_RT_PRIO, idx+1);
1226 static DEFINE_PER_CPU(cpumask_var_t, local_cpu_mask);
1228 static int find_lowest_rq(struct task_struct *task)
1230 struct sched_domain *sd;
1231 struct cpumask *lowest_mask = __get_cpu_var(local_cpu_mask);
1232 int this_cpu = smp_processor_id();
1233 int cpu = task_cpu(task);
1235 /* Make sure the mask is initialized first */
1236 if (unlikely(!lowest_mask))
1239 if (task->rt.nr_cpus_allowed == 1)
1240 return -1; /* No other targets possible */
1242 if (!cpupri_find(&task_rq(task)->rd->cpupri, task, lowest_mask))
1243 return -1; /* No targets found */
1246 * At this point we have built a mask of cpus representing the
1247 * lowest priority tasks in the system. Now we want to elect
1248 * the best one based on our affinity and topology.
1250 * We prioritize the last cpu that the task executed on since
1251 * it is most likely cache-hot in that location.
1253 if (cpumask_test_cpu(cpu, lowest_mask))
1257 * Otherwise, we consult the sched_domains span maps to figure
1258 * out which cpu is logically closest to our hot cache data.
1260 if (!cpumask_test_cpu(this_cpu, lowest_mask))
1261 this_cpu = -1; /* Skip this_cpu opt if not among lowest */
1264 for_each_domain(cpu, sd) {
1265 if (sd->flags & SD_WAKE_AFFINE) {
1269 * "this_cpu" is cheaper to preempt than a
1272 if (this_cpu != -1 &&
1273 cpumask_test_cpu(this_cpu, sched_domain_span(sd))) {
1278 best_cpu = cpumask_first_and(lowest_mask,
1279 sched_domain_span(sd));
1280 if (best_cpu < nr_cpu_ids) {
1289 * And finally, if there were no matches within the domains
1290 * just give the caller *something* to work with from the compatible
1296 cpu = cpumask_any(lowest_mask);
1297 if (cpu < nr_cpu_ids)
1302 /* Will lock the rq it finds */
1303 static struct rq *find_lock_lowest_rq(struct task_struct *task, struct rq *rq)
1305 struct rq *lowest_rq = NULL;
1309 for (tries = 0; tries < RT_MAX_TRIES; tries++) {
1310 cpu = find_lowest_rq(task);
1312 if ((cpu == -1) || (cpu == rq->cpu))
1315 lowest_rq = cpu_rq(cpu);
1317 /* if the prio of this runqueue changed, try again */
1318 if (double_lock_balance(rq, lowest_rq)) {
1320 * We had to unlock the run queue. In
1321 * the mean time, task could have
1322 * migrated already or had its affinity changed.
1323 * Also make sure that it wasn't scheduled on its rq.
1325 if (unlikely(task_rq(task) != rq ||
1326 !cpumask_test_cpu(lowest_rq->cpu,
1327 tsk_cpus_allowed(task)) ||
1328 task_running(rq, task) ||
1331 raw_spin_unlock(&lowest_rq->lock);
1337 /* If this rq is still suitable use it. */
1338 if (lowest_rq->rt.highest_prio.curr > task->prio)
1342 double_unlock_balance(rq, lowest_rq);
1349 static struct task_struct *pick_next_pushable_task(struct rq *rq)
1351 struct task_struct *p;
1353 if (!has_pushable_tasks(rq))
1356 p = plist_first_entry(&rq->rt.pushable_tasks,
1357 struct task_struct, pushable_tasks);
1359 BUG_ON(rq->cpu != task_cpu(p));
1360 BUG_ON(task_current(rq, p));
1361 BUG_ON(p->rt.nr_cpus_allowed <= 1);
1364 BUG_ON(!rt_task(p));
1370 * If the current CPU has more than one RT task, see if the non
1371 * running task can migrate over to a CPU that is running a task
1372 * of lesser priority.
1374 static int push_rt_task(struct rq *rq)
1376 struct task_struct *next_task;
1377 struct rq *lowest_rq;
1380 if (!rq->rt.overloaded)
1383 next_task = pick_next_pushable_task(rq);
1388 if (unlikely(next_task == rq->curr)) {
1394 * It's possible that the next_task slipped in of
1395 * higher priority than current. If that's the case
1396 * just reschedule current.
1398 if (unlikely(next_task->prio < rq->curr->prio)) {
1399 resched_task(rq->curr);
1403 /* We might release rq lock */
1404 get_task_struct(next_task);
1406 /* find_lock_lowest_rq locks the rq if found */
1407 lowest_rq = find_lock_lowest_rq(next_task, rq);
1409 struct task_struct *task;
1411 * find_lock_lowest_rq releases rq->lock
1412 * so it is possible that next_task has migrated.
1414 * We need to make sure that the task is still on the same
1415 * run-queue and is also still the next task eligible for
1418 task = pick_next_pushable_task(rq);
1419 if (task_cpu(next_task) == rq->cpu && task == next_task) {
1421 * The task hasn't migrated, and is still the next
1422 * eligible task, but we failed to find a run-queue
1423 * to push it to. Do not retry in this case, since
1424 * other cpus will pull from us when ready.
1430 /* No more tasks, just exit */
1434 * Something has shifted, try again.
1436 put_task_struct(next_task);
1441 deactivate_task(rq, next_task, 0);
1442 set_task_cpu(next_task, lowest_rq->cpu);
1443 activate_task(lowest_rq, next_task, 0);
1446 resched_task(lowest_rq->curr);
1448 double_unlock_balance(rq, lowest_rq);
1451 put_task_struct(next_task);
1456 static void push_rt_tasks(struct rq *rq)
1458 /* push_rt_task will return true if it moved an RT */
1459 while (push_rt_task(rq))
1463 static int pull_rt_task(struct rq *this_rq)
1465 int this_cpu = this_rq->cpu, ret = 0, cpu;
1466 struct task_struct *p;
1469 if (likely(!rt_overloaded(this_rq)))
1472 for_each_cpu(cpu, this_rq->rd->rto_mask) {
1473 if (this_cpu == cpu)
1476 src_rq = cpu_rq(cpu);
1479 * Don't bother taking the src_rq->lock if the next highest
1480 * task is known to be lower-priority than our current task.
1481 * This may look racy, but if this value is about to go
1482 * logically higher, the src_rq will push this task away.
1483 * And if its going logically lower, we do not care
1485 if (src_rq->rt.highest_prio.next >=
1486 this_rq->rt.highest_prio.curr)
1490 * We can potentially drop this_rq's lock in
1491 * double_lock_balance, and another CPU could
1494 double_lock_balance(this_rq, src_rq);
1497 * Are there still pullable RT tasks?
1499 if (src_rq->rt.rt_nr_running <= 1)
1502 p = pick_next_highest_task_rt(src_rq, this_cpu);
1505 * Do we have an RT task that preempts
1506 * the to-be-scheduled task?
1508 if (p && (p->prio < this_rq->rt.highest_prio.curr)) {
1509 WARN_ON(p == src_rq->curr);
1513 * There's a chance that p is higher in priority
1514 * than what's currently running on its cpu.
1515 * This is just that p is wakeing up and hasn't
1516 * had a chance to schedule. We only pull
1517 * p if it is lower in priority than the
1518 * current task on the run queue
1520 if (p->prio < src_rq->curr->prio)
1525 deactivate_task(src_rq, p, 0);
1526 set_task_cpu(p, this_cpu);
1527 activate_task(this_rq, p, 0);
1529 * We continue with the search, just in
1530 * case there's an even higher prio task
1531 * in another runqueue. (low likelihood
1536 double_unlock_balance(this_rq, src_rq);
1542 static void pre_schedule_rt(struct rq *rq, struct task_struct *prev)
1544 /* Try to pull RT tasks here if we lower this rq's prio */
1545 if (rq->rt.highest_prio.curr > prev->prio)
1549 static void post_schedule_rt(struct rq *rq)
1555 * If we are not running and we are not going to reschedule soon, we should
1556 * try to push tasks away now
1558 static void task_woken_rt(struct rq *rq, struct task_struct *p)
1560 if (!task_running(rq, p) &&
1561 !test_tsk_need_resched(rq->curr) &&
1562 has_pushable_tasks(rq) &&
1563 p->rt.nr_cpus_allowed > 1 &&
1564 rt_task(rq->curr) &&
1565 (rq->curr->rt.nr_cpus_allowed < 2 ||
1566 rq->curr->prio <= p->prio))
1570 static void set_cpus_allowed_rt(struct task_struct *p,
1571 const struct cpumask *new_mask)
1573 int weight = cpumask_weight(new_mask);
1575 BUG_ON(!rt_task(p));
1578 * Update the migration status of the RQ if we have an RT task
1579 * which is running AND changing its weight value.
1581 if (p->on_rq && (weight != p->rt.nr_cpus_allowed)) {
1582 struct rq *rq = task_rq(p);
1584 if (!task_current(rq, p)) {
1586 * Make sure we dequeue this task from the pushable list
1587 * before going further. It will either remain off of
1588 * the list because we are no longer pushable, or it
1591 if (p->rt.nr_cpus_allowed > 1)
1592 dequeue_pushable_task(rq, p);
1595 * Requeue if our weight is changing and still > 1
1598 enqueue_pushable_task(rq, p);
1602 if ((p->rt.nr_cpus_allowed <= 1) && (weight > 1)) {
1603 rq->rt.rt_nr_migratory++;
1604 } else if ((p->rt.nr_cpus_allowed > 1) && (weight <= 1)) {
1605 BUG_ON(!rq->rt.rt_nr_migratory);
1606 rq->rt.rt_nr_migratory--;
1609 update_rt_migration(&rq->rt);
1612 cpumask_copy(&p->cpus_allowed, new_mask);
1613 p->rt.nr_cpus_allowed = weight;
1616 /* Assumes rq->lock is held */
1617 static void rq_online_rt(struct rq *rq)
1619 if (rq->rt.overloaded)
1620 rt_set_overload(rq);
1622 __enable_runtime(rq);
1624 cpupri_set(&rq->rd->cpupri, rq->cpu, rq->rt.highest_prio.curr);
1627 /* Assumes rq->lock is held */
1628 static void rq_offline_rt(struct rq *rq)
1630 if (rq->rt.overloaded)
1631 rt_clear_overload(rq);
1633 __disable_runtime(rq);
1635 cpupri_set(&rq->rd->cpupri, rq->cpu, CPUPRI_INVALID);
1639 * When switch from the rt queue, we bring ourselves to a position
1640 * that we might want to pull RT tasks from other runqueues.
1642 static void switched_from_rt(struct rq *rq, struct task_struct *p)
1645 * If there are other RT tasks then we will reschedule
1646 * and the scheduling of the other RT tasks will handle
1647 * the balancing. But if we are the last RT task
1648 * we may need to handle the pulling of RT tasks
1651 if (p->on_rq && !rq->rt.rt_nr_running)
1655 static inline void init_sched_rt_class(void)
1659 for_each_possible_cpu(i)
1660 zalloc_cpumask_var_node(&per_cpu(local_cpu_mask, i),
1661 GFP_KERNEL, cpu_to_node(i));
1663 #endif /* CONFIG_SMP */
1666 * When switching a task to RT, we may overload the runqueue
1667 * with RT tasks. In this case we try to push them off to
1670 static void switched_to_rt(struct rq *rq, struct task_struct *p)
1672 int check_resched = 1;
1675 * If we are already running, then there's nothing
1676 * that needs to be done. But if we are not running
1677 * we may need to preempt the current running task.
1678 * If that current running task is also an RT task
1679 * then see if we can move to another run queue.
1681 if (p->on_rq && rq->curr != p) {
1683 if (rq->rt.overloaded && push_rt_task(rq) &&
1684 /* Don't resched if we changed runqueues */
1687 #endif /* CONFIG_SMP */
1688 if (check_resched && p->prio < rq->curr->prio)
1689 resched_task(rq->curr);
1694 * Priority of the task has changed. This may cause
1695 * us to initiate a push or pull.
1698 prio_changed_rt(struct rq *rq, struct task_struct *p, int oldprio)
1703 if (rq->curr == p) {
1706 * If our priority decreases while running, we
1707 * may need to pull tasks to this runqueue.
1709 if (oldprio < p->prio)
1712 * If there's a higher priority task waiting to run
1713 * then reschedule. Note, the above pull_rt_task
1714 * can release the rq lock and p could migrate.
1715 * Only reschedule if p is still on the same runqueue.
1717 if (p->prio > rq->rt.highest_prio.curr && rq->curr == p)
1720 /* For UP simply resched on drop of prio */
1721 if (oldprio < p->prio)
1723 #endif /* CONFIG_SMP */
1726 * This task is not running, but if it is
1727 * greater than the current running task
1730 if (p->prio < rq->curr->prio)
1731 resched_task(rq->curr);
1735 static void watchdog(struct rq *rq, struct task_struct *p)
1737 unsigned long soft, hard;
1739 /* max may change after cur was read, this will be fixed next tick */
1740 soft = task_rlimit(p, RLIMIT_RTTIME);
1741 hard = task_rlimit_max(p, RLIMIT_RTTIME);
1743 if (soft != RLIM_INFINITY) {
1747 next = DIV_ROUND_UP(min(soft, hard), USEC_PER_SEC/HZ);
1748 if (p->rt.timeout > next)
1749 p->cputime_expires.sched_exp = p->se.sum_exec_runtime;
1753 static void task_tick_rt(struct rq *rq, struct task_struct *p, int queued)
1760 * RR tasks need a special form of timeslice management.
1761 * FIFO tasks have no timeslices.
1763 if (p->policy != SCHED_RR)
1766 if (--p->rt.time_slice)
1769 p->rt.time_slice = DEF_TIMESLICE;
1772 * Requeue to the end of queue if we are not the only element
1775 if (p->rt.run_list.prev != p->rt.run_list.next) {
1776 requeue_task_rt(rq, p, 0);
1777 set_tsk_need_resched(p);
1781 static void set_curr_task_rt(struct rq *rq)
1783 struct task_struct *p = rq->curr;
1785 p->se.exec_start = rq->clock_task;
1787 /* The running task is never eligible for pushing */
1788 dequeue_pushable_task(rq, p);
1791 static unsigned int get_rr_interval_rt(struct rq *rq, struct task_struct *task)
1794 * Time slice is 0 for SCHED_FIFO tasks
1796 if (task->policy == SCHED_RR)
1797 return DEF_TIMESLICE;
1802 static const struct sched_class rt_sched_class = {
1803 .next = &fair_sched_class,
1804 .enqueue_task = enqueue_task_rt,
1805 .dequeue_task = dequeue_task_rt,
1806 .yield_task = yield_task_rt,
1808 .check_preempt_curr = check_preempt_curr_rt,
1810 .pick_next_task = pick_next_task_rt,
1811 .put_prev_task = put_prev_task_rt,
1814 .select_task_rq = select_task_rq_rt,
1816 .set_cpus_allowed = set_cpus_allowed_rt,
1817 .rq_online = rq_online_rt,
1818 .rq_offline = rq_offline_rt,
1819 .pre_schedule = pre_schedule_rt,
1820 .post_schedule = post_schedule_rt,
1821 .task_woken = task_woken_rt,
1822 .switched_from = switched_from_rt,
1825 .set_curr_task = set_curr_task_rt,
1826 .task_tick = task_tick_rt,
1828 .get_rr_interval = get_rr_interval_rt,
1830 .prio_changed = prio_changed_rt,
1831 .switched_to = switched_to_rt,
1834 #ifdef CONFIG_SCHED_DEBUG
1835 extern void print_rt_rq(struct seq_file *m, int cpu, struct rt_rq *rt_rq);
1837 static void print_rt_stats(struct seq_file *m, int cpu)
1840 struct rt_rq *rt_rq;
1843 for_each_rt_rq(rt_rq, iter, cpu_rq(cpu))
1844 print_rt_rq(m, cpu, rt_rq);
1847 #endif /* CONFIG_SCHED_DEBUG */