diff options
Diffstat (limited to 'kernel/sched/deadline.c')
| -rw-r--r-- | kernel/sched/deadline.c | 78 |
1 files changed, 43 insertions, 35 deletions
diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c index 9df09782025c..8b7c2b35bec9 100644 --- a/kernel/sched/deadline.c +++ b/kernel/sched/deadline.c @@ -17,9 +17,6 @@ */ #include "sched.h" -#include <linux/slab.h> -#include <uapi/linux/sched/types.h> - struct dl_bandwidth def_dl_bandwidth; static inline struct task_struct *dl_task_of(struct sched_dl_entity *dl_se) @@ -514,7 +511,7 @@ static DEFINE_PER_CPU(struct callback_head, dl_pull_head); static void push_dl_tasks(struct rq *); static void pull_dl_task(struct rq *); -static inline void queue_push_tasks(struct rq *rq) +static inline void deadline_queue_push_tasks(struct rq *rq) { if (!has_pushable_dl_tasks(rq)) return; @@ -522,7 +519,7 @@ static inline void queue_push_tasks(struct rq *rq) queue_balance_callback(rq, &per_cpu(dl_push_head, rq->cpu), push_dl_tasks); } -static inline void queue_pull_task(struct rq *rq) +static inline void deadline_queue_pull_task(struct rq *rq) { queue_balance_callback(rq, &per_cpu(dl_pull_head, rq->cpu), pull_dl_task); } @@ -539,12 +536,12 @@ static struct rq *dl_task_offline_migration(struct rq *rq, struct task_struct *p /* * If we cannot preempt any rq, fall back to pick any - * online cpu. + * online CPU: */ cpu = cpumask_any_and(cpu_active_mask, &p->cpus_allowed); if (cpu >= nr_cpu_ids) { /* - * Fail to find any suitable cpu. + * Failed to find any suitable CPU. * The task will never come back! */ BUG_ON(dl_bandwidth_enabled()); @@ -597,19 +594,18 @@ static inline void pull_dl_task(struct rq *rq) { } -static inline void queue_push_tasks(struct rq *rq) +static inline void deadline_queue_push_tasks(struct rq *rq) { } -static inline void queue_pull_task(struct rq *rq) +static inline void deadline_queue_pull_task(struct rq *rq) { } #endif /* CONFIG_SMP */ static void enqueue_task_dl(struct rq *rq, struct task_struct *p, int flags); static void __dequeue_task_dl(struct rq *rq, struct task_struct *p, int flags); -static void check_preempt_curr_dl(struct rq *rq, struct task_struct *p, - int flags); +static void check_preempt_curr_dl(struct rq *rq, struct task_struct *p, int flags); /* * We are being explicitly informed that a new instance is starting, @@ -1763,7 +1759,7 @@ pick_next_task_dl(struct rq *rq, struct task_struct *prev, struct rq_flags *rf) if (hrtick_enabled(rq)) start_hrtick_dl(rq, p); - queue_push_tasks(rq); + deadline_queue_push_tasks(rq); return p; } @@ -1776,6 +1772,14 @@ static void put_prev_task_dl(struct rq *rq, struct task_struct *p) enqueue_pushable_dl_task(rq, p); } +/* + * scheduler tick hitting a task of our scheduling class. + * + * NOTE: This function can be called remotely by the tick offload that + * goes along full dynticks. Therefore no local assumption can be made + * and everything must be accessed through the @rq and @curr passed in + * parameters. + */ static void task_tick_dl(struct rq *rq, struct task_struct *p, int queued) { update_curr_dl(rq); @@ -1865,7 +1869,7 @@ static int find_later_rq(struct task_struct *task) /* * We have to consider system topology and task affinity - * first, then we can look for a suitable cpu. + * first, then we can look for a suitable CPU. */ if (!cpudl_find(&task_rq(task)->rd->cpudl, task, later_mask)) return -1; @@ -1879,7 +1883,7 @@ static int find_later_rq(struct task_struct *task) * Now we check how well this matches with task's * affinity and system topology. * - * The last cpu where the task run is our first + * The last CPU where the task run is our first * guess, since it is most likely cache-hot there. */ if (cpumask_test_cpu(cpu, later_mask)) @@ -1909,9 +1913,9 @@ static int find_later_rq(struct task_struct *task) best_cpu = cpumask_first_and(later_mask, sched_domain_span(sd)); /* - * Last chance: if a cpu being in both later_mask + * Last chance: if a CPU being in both later_mask * and current sd span is valid, that becomes our - * choice. Of course, the latest possible cpu is + * choice. Of course, the latest possible CPU is * already under consideration through later_mask. */ if (best_cpu < nr_cpu_ids) { @@ -2067,7 +2071,7 @@ retry: if (task == next_task) { /* * The task is still there. We don't try - * again, some other cpu will pull it when ready. + * again, some other CPU will pull it when ready. */ goto out; } @@ -2300,12 +2304,12 @@ static void switched_from_dl(struct rq *rq, struct task_struct *p) /* * Since this might be the only -deadline task on the rq, * this is the right place to try to pull some other one - * from an overloaded cpu, if any. + * from an overloaded CPU, if any. */ if (!task_on_rq_queued(p) || rq->dl.dl_nr_running) return; - queue_pull_task(rq); + deadline_queue_pull_task(rq); } /* @@ -2327,7 +2331,7 @@ static void switched_to_dl(struct rq *rq, struct task_struct *p) if (rq->curr != p) { #ifdef CONFIG_SMP if (p->nr_cpus_allowed > 1 && rq->dl.overloaded) - queue_push_tasks(rq); + deadline_queue_push_tasks(rq); #endif if (dl_task(rq->curr)) check_preempt_curr_dl(rq, p, 0); @@ -2352,7 +2356,7 @@ static void prio_changed_dl(struct rq *rq, struct task_struct *p, * or lowering its prio, so... */ if (!rq->dl.overloaded) - queue_pull_task(rq); + deadline_queue_pull_task(rq); /* * If we now have a earlier deadline task than p, @@ -2626,17 +2630,17 @@ void __dl_clear_params(struct task_struct *p) { struct sched_dl_entity *dl_se = &p->dl; - dl_se->dl_runtime = 0; - dl_se->dl_deadline = 0; - dl_se->dl_period = 0; - dl_se->flags = 0; - dl_se->dl_bw = 0; - dl_se->dl_density = 0; + dl_se->dl_runtime = 0; + dl_se->dl_deadline = 0; + dl_se->dl_period = 0; + dl_se->flags = 0; + dl_se->dl_bw = 0; + dl_se->dl_density = 0; - dl_se->dl_throttled = 0; - dl_se->dl_yielded = 0; - dl_se->dl_non_contending = 0; - dl_se->dl_overrun = 0; + dl_se->dl_throttled = 0; + dl_se->dl_yielded = 0; + dl_se->dl_non_contending = 0; + dl_se->dl_overrun = 0; } bool dl_param_changed(struct task_struct *p, const struct sched_attr *attr) @@ -2655,21 +2659,22 @@ bool dl_param_changed(struct task_struct *p, const struct sched_attr *attr) #ifdef CONFIG_SMP int dl_task_can_attach(struct task_struct *p, const struct cpumask *cs_cpus_allowed) { - unsigned int dest_cpu = cpumask_any_and(cpu_active_mask, - cs_cpus_allowed); + unsigned int dest_cpu; struct dl_bw *dl_b; bool overflow; int cpus, ret; unsigned long flags; + dest_cpu = cpumask_any_and(cpu_active_mask, cs_cpus_allowed); + rcu_read_lock_sched(); dl_b = dl_bw_of(dest_cpu); raw_spin_lock_irqsave(&dl_b->lock, flags); cpus = dl_bw_cpus(dest_cpu); overflow = __dl_overflow(dl_b, cpus, 0, p->dl.dl_bw); - if (overflow) + if (overflow) { ret = -EBUSY; - else { + } else { /* * We reserve space for this task in the destination * root_domain, as we can't fail after this point. @@ -2681,6 +2686,7 @@ int dl_task_can_attach(struct task_struct *p, const struct cpumask *cs_cpus_allo } raw_spin_unlock_irqrestore(&dl_b->lock, flags); rcu_read_unlock_sched(); + return ret; } @@ -2701,6 +2707,7 @@ int dl_cpuset_cpumask_can_shrink(const struct cpumask *cur, ret = 0; raw_spin_unlock_irqrestore(&cur_dl_b->lock, flags); rcu_read_unlock_sched(); + return ret; } @@ -2718,6 +2725,7 @@ bool dl_cpu_busy(unsigned int cpu) overflow = __dl_overflow(dl_b, cpus, 0, 0); raw_spin_unlock_irqrestore(&dl_b->lock, flags); rcu_read_unlock_sched(); + return overflow; } #endif |