/* * Real-Time Scheduling Class (mapped to the SCHED_FIFO and SCHED_RR * policies) */ #ifdef CONFIG_RT_GROUP_SCHED #define rt_entity_is_task(rt_se) (!(rt_se)->my_q) static inline struct task_struct *rt_task_of(struct sched_rt_entity *rt_se){#ifdef CONFIG_SCHED_DEBUG WARN_ON_ONCE(!rt_entity_is_task(rt_se));#endif return container_of(rt_se, struct task_struct, rt);} static inline struct rq *rq_of_rt_rq(struct rt_rq *rt_rq){ return rt_rq->rq;} static inline struct rt_rq *rt_rq_of_se(struct sched_rt_entity *rt_se){ return rt_se->rt_rq;} #else /* CONFIG_RT_GROUP_SCHED */ #define rt_entity_is_task(rt_se) (1) static inline struct task_struct *rt_task_of(struct sched_rt_entity *rt_se){ return container_of(rt_se, struct task_struct, rt);} static inline struct rq *rq_of_rt_rq(struct rt_rq *rt_rq){ return container_of(rt_rq, struct rq, rt);} static inline struct rt_rq *rt_rq_of_se(struct sched_rt_entity *rt_se){ struct task_struct *p = rt_task_of(rt_se); struct rq *rq = task_rq(p); return &rq->rt;} #endif /* CONFIG_RT_GROUP_SCHED */ #ifdef CONFIG_SMP static inline int rt_overloaded(struct rq *rq){ return atomic_read(&rq->rd->rto_count);} static inline void rt_set_overload(struct rq *rq){ if (!rq->online) return; cpumask_set_cpu(rq->cpu, rq->rd->rto_mask); /* * Make sure the mask is visible before we set * the overload count. That is checked to determine * if we should look at the mask. It would be a shame * if we looked at the mask, but the mask was not * updated yet. */ wmb(); atomic_inc(&rq->rd->rto_count);} static inline void rt_clear_overload(struct rq *rq){ if (!rq->online) return; /* the order here really doesn't matter */ atomic_dec(&rq->rd->rto_count); cpumask_clear_cpu(rq->cpu, rq->rd->rto_mask);} static void update_rt_migration(struct rt_rq *rt_rq){ if (rt_rq->rt_nr_migratory && rt_rq->rt_nr_total > 1) { if (!rt_rq->overloaded) { rt_set_overload(rq_of_rt_rq(rt_rq)); rt_rq->overloaded = 1; } } else if (rt_rq->overloaded) { rt_clear_overload(rq_of_rt_rq(rt_rq)); rt_rq->overloaded = 0; }} static void inc_rt_migration(struct sched_rt_entity *rt_se, struct rt_rq *rt_rq){ if (!rt_entity_is_task(rt_se)) return; rt_rq = &rq_of_rt_rq(rt_rq)->rt; rt_rq->rt_nr_total++; if (rt_se->nr_cpus_allowed > 1) rt_rq->rt_nr_migratory++; update_rt_migration(rt_rq);} static void dec_rt_migration(struct sched_rt_entity *rt_se, struct rt_rq *rt_rq){ if (!rt_entity_is_task(rt_se)) return; rt_rq = &rq_of_rt_rq(rt_rq)->rt; rt_rq->rt_nr_total--; if (rt_se->nr_cpus_allowed > 1) rt_rq->rt_nr_migratory--; update_rt_migration(rt_rq);} static void enqueue_pushable_task(struct rq *rq, struct task_struct *p){ plist_del(&p->pushable_tasks, &rq->rt.pushable_tasks); plist_node_init(&p->pushable_tasks, p->prio); plist_add(&p->pushable_tasks, &rq->rt.pushable_tasks);} static void dequeue_pushable_task(struct rq *rq, struct task_struct *p){ plist_del(&p->pushable_tasks, &rq->rt.pushable_tasks);} static inline int has_pushable_tasks(struct rq *rq){ return !plist_head_empty(&rq->rt.pushable_tasks);} #else static inline void enqueue_pushable_task(struct rq *rq, struct task_struct *p){} static inline void dequeue_pushable_task(struct rq *rq, struct task_struct *p){} static inlinevoid inc_rt_migration(struct sched_rt_entity *rt_se, struct rt_rq *rt_rq){} static inlinevoid dec_rt_migration(struct sched_rt_entity *rt_se, struct rt_rq *rt_rq){} #endif /* CONFIG_SMP */ static inline int on_rt_rq(struct sched_rt_entity *rt_se){ return !list_empty(&rt_se->run_list);} #ifdef CONFIG_RT_GROUP_SCHED static inline u64 sched_rt_runtime(struct rt_rq *rt_rq){ if (!rt_rq->tg) return RUNTIME_INF; return rt_rq->rt_runtime;} static inline u64 sched_rt_period(struct rt_rq *rt_rq){ return ktime_to_ns(rt_rq->tg->rt_bandwidth.rt_period);} static inline void list_add_leaf_rt_rq(struct rt_rq *rt_rq){ list_add_rcu(&rt_rq->leaf_rt_rq_list, &rq_of_rt_rq(rt_rq)->leaf_rt_rq_list);} static inline void list_del_leaf_rt_rq(struct rt_rq *rt_rq){ list_del_rcu(&rt_rq->leaf_rt_rq_list);} #define for_each_leaf_rt_rq(rt_rq, rq) \ list_for_each_entry_rcu(rt_rq, &rq->leaf_rt_rq_list, leaf_rt_rq_list) #define for_each_sched_rt_entity(rt_se) \ for (; rt_se; rt_se = rt_se->parent) static inline struct rt_rq *group_rt_rq(struct sched_rt_entity *rt_se){ return rt_se->my_q;} static void enqueue_rt_entity(struct sched_rt_entity *rt_se, bool head);static void dequeue_rt_entity(struct sched_rt_entity *rt_se); static void sched_rt_rq_enqueue(struct rt_rq *rt_rq){ struct task_struct *curr = rq_of_rt_rq(rt_rq)->curr; struct sched_rt_entity *rt_se; int cpu = cpu_of(rq_of_rt_rq(rt_rq)); rt_se = rt_rq->tg->rt_se[cpu]; if (rt_rq->rt_nr_running) { if (rt_se && !on_rt_rq(rt_se)) enqueue_rt_entity(rt_se, false); if (rt_rq->highest_prio.curr < curr->prio) resched_task(curr); }} static void sched_rt_rq_dequeue(struct rt_rq *rt_rq){ struct sched_rt_entity *rt_se; int cpu = cpu_of(rq_of_rt_rq(rt_rq)); rt_se = rt_rq->tg->rt_se[cpu]; if (rt_se && on_rt_rq(rt_se)) dequeue_rt_entity(rt_se);} static inline int rt_rq_throttled(struct rt_rq *rt_rq){ return rt_rq->rt_throttled && !rt_rq->rt_nr_boosted;} static int rt_se_boosted(struct sched_rt_entity *rt_se){ struct rt_rq *rt_rq = group_rt_rq(rt_se); struct task_struct *p; if (rt_rq) return !!rt_rq->rt_nr_boosted; p = rt_task_of(rt_se); return p->prio != p->normal_prio;} #ifdef CONFIG_SMPstatic inline const struct cpumask *sched_rt_period_mask(void){ return cpu_rq(smp_processor_id())->rd->span;}#elsestatic inline const struct cpumask *sched_rt_period_mask(void){ return cpu_online_mask;}#endif static inlinestruct rt_rq *sched_rt_period_rt_rq(struct rt_bandwidth *rt_b, int cpu){ return container_of(rt_b, struct task_group, rt_bandwidth)->rt_rq[cpu];} static inline struct rt_bandwidth *sched_rt_bandwidth(struct rt_rq *rt_rq){ return &rt_rq->tg->rt_bandwidth;} #else /* !CONFIG_RT_GROUP_SCHED */ static inline u64 sched_rt_runtime(struct rt_rq *rt_rq){ return rt_rq->rt_runtime;} static inline u64 sched_rt_period(struct rt_rq *rt_rq){ return ktime_to_ns(def_rt_bandwidth.rt_period);} static inline void list_add_leaf_rt_rq(struct rt_rq *rt_rq){} static inline void list_del_leaf_rt_rq(struct rt_rq *rt_rq){} #define for_each_leaf_rt_rq(rt_rq, rq) \ for (rt_rq = &rq->rt; rt_rq; rt_rq = NULL) #define for_each_sched_rt_entity(rt_se) \ for (; rt_se; rt_se = NULL) static inline struct rt_rq *group_rt_rq(struct sched_rt_entity *rt_se){ return NULL;} static inline void sched_rt_rq_enqueue(struct rt_rq *rt_rq){ if (rt_rq->rt_nr_running) resched_task(rq_of_rt_rq(rt_rq)->curr);} static inline void sched_rt_rq_dequeue(struct rt_rq *rt_rq){} static inline int rt_rq_throttled(struct rt_rq *rt_rq){ return rt_rq->rt_throttled;} static inline const struct cpumask *sched_rt_period_mask(void){ return cpu_online_mask;} static inlinestruct rt_rq *sched_rt_period_rt_rq(struct rt_bandwidth *rt_b, int cpu){ return &cpu_rq(cpu)->rt;} static inline struct rt_bandwidth *sched_rt_bandwidth(struct rt_rq *rt_rq){ return &def_rt_bandwidth;} #endif /* CONFIG_RT_GROUP_SCHED */ #ifdef CONFIG_SMP/* * We ran out of runtime, see if we can borrow some from our neighbours. */static int do_balance_runtime(struct rt_rq *rt_rq){ struct rt_bandwidth *rt_b = sched_rt_bandwidth(rt_rq); struct root_domain *rd = cpu_rq(smp_processor_id())->rd; int i, weight, more = 0; u64 rt_period; weight = cpumask_weight(rd->span); raw_spin_lock(&rt_b->rt_runtime_lock); rt_period = ktime_to_ns(rt_b->rt_period); for_each_cpu(i, rd->span) { struct rt_rq *iter = sched_rt_period_rt_rq(rt_b, i); s64 diff; if (iter == rt_rq) continue; raw_spin_lock(&iter->rt_runtime_lock); /* * Either all rqs have inf runtime and there's nothing to steal * or __disable_runtime() below sets a specific rq to inf to * indicate its been disabled and disalow stealing. */ if (iter->rt_runtime == RUNTIME_INF) goto next; /* * From runqueues with spare time, take 1/n part of their * spare time, but no more than our period. */ diff = iter->rt_runtime - iter->rt_time; if (diff > 0) { diff = div_u64((u64)diff, weight); if (rt_rq->rt_runtime + diff > rt_period) diff = rt_period - rt_rq->rt_runtime; iter->rt_runtime -= diff; rt_rq->rt_runtime += diff; more = 1; if (rt_rq->rt_runtime == rt_period) { raw_spin_unlock(&iter->rt_runtime_lock); break; } }next: raw_spin_unlock(&iter->rt_runtime_lock); } raw_spin_unlock(&rt_b->rt_runtime_lock); return more;} /* * Ensure this RQ takes back all the runtime it lend to its neighbours. */static void __disable_runtime(struct rq *rq){ struct root_domain *rd = rq->rd; struct rt_rq *rt_rq; if (unlikely(!scheduler_running)) return; for_each_leaf_rt_rq(rt_rq, rq) { struct rt_bandwidth *rt_b = sched_rt_bandwidth(rt_rq); s64 want; int i; raw_spin_lock(&rt_b->rt_runtime_lock); raw_spin_lock(&rt_rq->rt_runtime_lock); /* * Either we're all inf and nobody needs to borrow, or we're * already disabled and thus have nothing to do, or we have * exactly the right amount of runtime to take out. */ if (rt_rq->rt_runtime == RUNTIME_INF || rt_rq->rt_runtime == rt_b->rt_runtime) goto balanced; raw_spin_unlock(&rt_rq->rt_runtime_lock); /* * Calculate the difference between what we started out with * and what we current have, that's the amount of runtime * we lend and now have to reclaim. */ want = rt_b->rt_runtime - rt_rq->rt_runtime; /* * Greedy reclaim, take back as much as we can. */ for_each_cpu(i, rd->span) { struct rt_rq *iter = sched_rt_period_rt_rq(rt_b, i); s64 diff; /* * Can't reclaim from ourselves or disabled runqueues. */ if (iter == rt_rq || iter->rt_runtime == RUNTIME_INF) continue; raw_spin_lock(&iter->rt_runtime_lock); if (want > 0) { diff = min_t(s64, iter->rt_runtime, want); iter->rt_runtime -= diff; want -= diff; } else { iter->rt_runtime -= want; want -= want; } raw_spin_unlock(&iter->rt_runtime_lock); if (!want) break; } raw_spin_lock(&rt_rq->rt_runtime_lock); /* * We cannot be left wanting - that would mean some runtime * leaked out of the system. */ BUG_ON(want);balanced: /* * Disable all the borrow logic by pretending we have inf * runtime - in which case borrowing doesn't make sense. */ rt_rq->rt_runtime = RUNTIME_INF; raw_spin_unlock(&rt_rq->rt_runtime_lock); raw_spin_unlock(&rt_b->rt_runtime_lock); }} static void disable_runtime(struct rq *rq){ unsigned long flags; raw_spin_lock_irqsave(&rq->lock, flags); __disable_runtime(rq); raw_spin_unlock_irqrestore(&rq->lock, flags);} static void __enable_runtime(struct rq *rq){ struct rt_rq *rt_rq; if (unlikely(!scheduler_running)) return; /* * Reset each runqueue's bandwidth settings */ for_each_leaf_rt_rq(rt_rq, rq) { struct rt_bandwidth *rt_b = sched_rt_bandwidth(rt_rq); Lines 1–500 of 1807. 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/* * Real-Time Scheduling Class (mapped to the SCHED_FIFO and SCHED_RR * policies) */ #ifdef CONFIG_RT_GROUP_SCHED #define rt_entity_is_task(rt_se) (!(rt_se)->my_q) static inline struct task_struct *rt_task_of(struct sched_rt_entity *rt_se) { #ifdef CONFIG_SCHED_DEBUG WARN_ON_ONCE(!rt_entity_is_task(rt_se)); #endif return container_of(rt_se, struct task_struct, rt); } static inline struct rq *rq_of_rt_rq(struct rt_rq *rt_rq) { return rt_rq->rq; } static inline struct rt_rq *rt_rq_of_se(struct sched_rt_entity *rt_se) { return rt_se->rt_rq; } #else /* CONFIG_RT_GROUP_SCHED */ #define rt_entity_is_task(rt_se) (1) static inline struct task_struct *rt_task_of(struct sched_rt_entity *rt_se) { return container_of(rt_se, struct task_struct, rt); } static inline struct rq *rq_of_rt_rq(struct rt_rq *rt_rq) { return container_of(rt_rq, struct rq, rt); } static inline struct rt_rq *rt_rq_of_se(struct sched_rt_entity *rt_se) { struct task_struct *p = rt_task_of(rt_se); struct rq *rq = task_rq(p); return &rq->rt; } #endif /* CONFIG_RT_GROUP_SCHED */ #ifdef CONFIG_SMP static inline int rt_overloaded(struct rq *rq) { return atomic_read(&rq->rd->rto_count); } static inline void rt_set_overload(struct rq *rq) { if (!rq->online) return; cpumask_set_cpu(rq->cpu, rq->rd->rto_mask); /* * Make sure the mask is visible before we set * the overload count. That is checked to determine * if we should look at the mask. It would be a shame * if we looked at the mask, but the mask was not * updated yet. */ wmb(); atomic_inc(&rq->rd->rto_count); } static inline void rt_clear_overload(struct rq *rq) { if (!rq->online) return; /* the order here really doesn't matter */ atomic_dec(&rq->rd->rto_count); cpumask_clear_cpu(rq->cpu, rq->rd->rto_mask); } static void update_rt_migration(struct rt_rq *rt_rq) { if (rt_rq->rt_nr_migratory && rt_rq->rt_nr_total > 1) { if (!rt_rq->overloaded) { rt_set_overload(rq_of_rt_rq(rt_rq)); rt_rq->overloaded = 1; } } else if (rt_rq->overloaded) { rt_clear_overload(rq_of_rt_rq(rt_rq)); rt_rq->overloaded = 0; } } static void inc_rt_migration(struct sched_rt_entity *rt_se, struct rt_rq *rt_rq) { if (!rt_entity_is_task(rt_se)) return; rt_rq = &rq_of_rt_rq(rt_rq)->rt; rt_rq->rt_nr_total++; if (rt_se->nr_cpus_allowed > 1) rt_rq->rt_nr_migratory++; update_rt_migration(rt_rq); } static void dec_rt_migration(struct sched_rt_entity *rt_se, struct rt_rq *rt_rq) { if (!rt_entity_is_task(rt_se)) return; rt_rq = &rq_of_rt_rq(rt_rq)->rt; rt_rq->rt_nr_total--; if (rt_se->nr_cpus_allowed > 1) rt_rq->rt_nr_migratory--; update_rt_migration(rt_rq); } static void enqueue_pushable_task(struct rq *rq, struct task_struct *p) { plist_del(&p->pushable_tasks, &rq->rt.pushable_tasks); plist_node_init(&p->pushable_tasks, p->prio); plist_add(&p->pushable_tasks, &rq->rt.pushable_tasks); } static void dequeue_pushable_task(struct rq *rq, struct task_struct *p) { plist_del(&p->pushable_tasks, &rq->rt.pushable_tasks); } static inline int has_pushable_tasks(struct rq *rq) { return !plist_head_empty(&rq->rt.pushable_tasks); } #else static inline void enqueue_pushable_task(struct rq *rq, struct task_struct *p) { } static inline void dequeue_pushable_task(struct rq *rq, struct task_struct *p) { } static inline void inc_rt_migration(struct sched_rt_entity *rt_se, struct rt_rq *rt_rq) { } static inline void dec_rt_migration(struct sched_rt_entity *rt_se, struct rt_rq *rt_rq) { } #endif /* CONFIG_SMP */ static inline int on_rt_rq(struct sched_rt_entity *rt_se) { return !list_empty(&rt_se->run_list); } #ifdef CONFIG_RT_GROUP_SCHED static inline u64 sched_rt_runtime(struct rt_rq *rt_rq) { if (!rt_rq->tg) return RUNTIME_INF; return rt_rq->rt_runtime; } static inline u64 sched_rt_period(struct rt_rq *rt_rq) { return ktime_to_ns(rt_rq->tg->rt_bandwidth.rt_period); } static inline void list_add_leaf_rt_rq(struct rt_rq *rt_rq) { list_add_rcu(&rt_rq->leaf_rt_rq_list, &rq_of_rt_rq(rt_rq)->leaf_rt_rq_list); } static inline void list_del_leaf_rt_rq(struct rt_rq *rt_rq) { list_del_rcu(&rt_rq->leaf_rt_rq_list); } #define for_each_leaf_rt_rq(rt_rq, rq) \ list_for_each_entry_rcu(rt_rq, &rq->leaf_rt_rq_list, leaf_rt_rq_list) #define for_each_sched_rt_entity(rt_se) \ for (; rt_se; rt_se = rt_se->parent) static inline struct rt_rq *group_rt_rq(struct sched_rt_entity *rt_se) { return rt_se->my_q; } static void enqueue_rt_entity(struct sched_rt_entity *rt_se, bool head); static void dequeue_rt_entity(struct sched_rt_entity *rt_se); static void sched_rt_rq_enqueue(struct rt_rq *rt_rq) { struct task_struct *curr = rq_of_rt_rq(rt_rq)->curr; struct sched_rt_entity *rt_se; int cpu = cpu_of(rq_of_rt_rq(rt_rq)); rt_se = rt_rq->tg->rt_se[cpu]; if (rt_rq->rt_nr_running) { if (rt_se && !on_rt_rq(rt_se)) enqueue_rt_entity(rt_se, false); if (rt_rq->highest_prio.curr < curr->prio) resched_task(curr); } } static void sched_rt_rq_dequeue(struct rt_rq *rt_rq) { struct sched_rt_entity *rt_se; int cpu = cpu_of(rq_of_rt_rq(rt_rq)); rt_se = rt_rq->tg->rt_se[cpu]; if (rt_se && on_rt_rq(rt_se)) dequeue_rt_entity(rt_se); } static inline int rt_rq_throttled(struct rt_rq *rt_rq) { return rt_rq->rt_throttled && !rt_rq->rt_nr_boosted; } static int rt_se_boosted(struct sched_rt_entity *rt_se) { struct rt_rq *rt_rq = group_rt_rq(rt_se); struct task_struct *p; if (rt_rq) return !!rt_rq->rt_nr_boosted; p = rt_task_of(rt_se); return p->prio != p->normal_prio; } #ifdef CONFIG_SMP static inline const struct cpumask *sched_rt_period_mask(void) { return cpu_rq(smp_processor_id())->rd->span; } #else static inline const struct cpumask *sched_rt_period_mask(void) { return cpu_online_mask; } #endif static inline struct rt_rq *sched_rt_period_rt_rq(struct rt_bandwidth *rt_b, int cpu) { return container_of(rt_b, struct task_group, rt_bandwidth)->rt_rq[cpu]; } static inline struct rt_bandwidth *sched_rt_bandwidth(struct rt_rq *rt_rq) { return &rt_rq->tg->rt_bandwidth; } #else /* !CONFIG_RT_GROUP_SCHED */ static inline u64 sched_rt_runtime(struct rt_rq *rt_rq) { return rt_rq->rt_runtime; } static inline u64 sched_rt_period(struct rt_rq *rt_rq) { return ktime_to_ns(def_rt_bandwidth.rt_period); } static inline void list_add_leaf_rt_rq(struct rt_rq *rt_rq) { } static inline void list_del_leaf_rt_rq(struct rt_rq *rt_rq) { } #define for_each_leaf_rt_rq(rt_rq, rq) \ for (rt_rq = &rq->rt; rt_rq; rt_rq = NULL) #define for_each_sched_rt_entity(rt_se) \ for (; rt_se; rt_se = NULL) static inline struct rt_rq *group_rt_rq(struct sched_rt_entity *rt_se) { return NULL; } static inline void sched_rt_rq_enqueue(struct rt_rq *rt_rq) { if (rt_rq->rt_nr_running) resched_task(rq_of_rt_rq(rt_rq)->curr); } static inline void sched_rt_rq_dequeue(struct rt_rq *rt_rq) { } static inline int rt_rq_throttled(struct rt_rq *rt_rq) { return rt_rq->rt_throttled; } static inline const struct cpumask *sched_rt_period_mask(void) { return cpu_online_mask; } static inline struct rt_rq *sched_rt_period_rt_rq(struct rt_bandwidth *rt_b, int cpu) { return &cpu_rq(cpu)->rt; } static inline struct rt_bandwidth *sched_rt_bandwidth(struct rt_rq *rt_rq) { return &def_rt_bandwidth; } #endif /* CONFIG_RT_GROUP_SCHED */ #ifdef CONFIG_SMP /* * We ran out of runtime, see if we can borrow some from our neighbours. */ static int do_balance_runtime(struct rt_rq *rt_rq) { struct rt_bandwidth *rt_b = sched_rt_bandwidth(rt_rq); struct root_domain *rd = cpu_rq(smp_processor_id())->rd; int i, weight, more = 0; u64 rt_period; weight = cpumask_weight(rd->span); raw_spin_lock(&rt_b->rt_runtime_lock); rt_period = ktime_to_ns(rt_b->rt_period); for_each_cpu(i, rd->span) { struct rt_rq *iter = sched_rt_period_rt_rq(rt_b, i); s64 diff; if (iter == rt_rq) continue; raw_spin_lock(&iter->rt_runtime_lock); /* * Either all rqs have inf runtime and there's nothing to steal * or __disable_runtime() below sets a specific rq to inf to * indicate its been disabled and disalow stealing. */ if (iter->rt_runtime == RUNTIME_INF) goto next; /* * From runqueues with spare time, take 1/n part of their * spare time, but no more than our period. */ diff = iter->rt_runtime - iter->rt_time; if (diff > 0) { diff = div_u64((u64)diff, weight); if (rt_rq->rt_runtime + diff > rt_period) diff = rt_period - rt_rq->rt_runtime; iter->rt_runtime -= diff; rt_rq->rt_runtime += diff; more = 1; if (rt_rq->rt_runtime == rt_period) { raw_spin_unlock(&iter->rt_runtime_lock); break; } } next: raw_spin_unlock(&iter->rt_runtime_lock); } raw_spin_unlock(&rt_b->rt_runtime_lock); return more; } /* * Ensure this RQ takes back all the runtime it lend to its neighbours. */ static void __disable_runtime(struct rq *rq) { struct root_domain *rd = rq->rd; struct rt_rq *rt_rq; if (unlikely(!scheduler_running)) return; for_each_leaf_rt_rq(rt_rq, rq) { struct rt_bandwidth *rt_b = sched_rt_bandwidth(rt_rq); s64 want; int i; raw_spin_lock(&rt_b->rt_runtime_lock); raw_spin_lock(&rt_rq->rt_runtime_lock); /* * Either we're all inf and nobody needs to borrow, or we're * already disabled and thus have nothing to do, or we have * exactly the right amount of runtime to take out. */ if (rt_rq->rt_runtime == RUNTIME_INF || rt_rq->rt_runtime == rt_b->rt_runtime) goto balanced; raw_spin_unlock(&rt_rq->rt_runtime_lock); /* * Calculate the difference between what we started out with * and what we current have, that's the amount of runtime * we lend and now have to reclaim. */ want = rt_b->rt_runtime - rt_rq->rt_runtime; /* * Greedy reclaim, take back as much as we can. */ for_each_cpu(i, rd->span) { struct rt_rq *iter = sched_rt_period_rt_rq(rt_b, i); s64 diff; /* * Can't reclaim from ourselves or disabled runqueues. */ if (iter == rt_rq || iter->rt_runtime == RUNTIME_INF) continue; raw_spin_lock(&iter->rt_runtime_lock); if (want > 0) { diff = min_t(s64, iter->rt_runtime, want); iter->rt_runtime -= diff; want -= diff; } else { iter->rt_runtime -= want; want -= want; } raw_spin_unlock(&iter->rt_runtime_lock); if (!want) break; } raw_spin_lock(&rt_rq->rt_runtime_lock); /* * We cannot be left wanting - that would mean some runtime * leaked out of the system. */ BUG_ON(want); balanced: /* * Disable all the borrow logic by pretending we have inf * runtime - in which case borrowing doesn't make sense. */ rt_rq->rt_runtime = RUNTIME_INF; raw_spin_unlock(&rt_rq->rt_runtime_lock); raw_spin_unlock(&rt_b->rt_runtime_lock); } } static void disable_runtime(struct rq *rq) { unsigned long flags; raw_spin_lock_irqsave(&rq->lock, flags); __disable_runtime(rq); raw_spin_unlock_irqrestore(&rq->lock, flags); } static void __enable_runtime(struct rq *rq) { struct rt_rq *rt_rq; if (unlikely(!scheduler_running)) return; /* * Reset each runqueue's bandwidth settings */ for_each_leaf_rt_rq(rt_rq, rq) { struct rt_bandwidth *rt_b = sched_rt_bandwidth(rt_rq);