return ktime_to_ns(rt_rq->tg->rt_bandwidth.rt_period);
}
+typedef struct task_group *rt_rq_iter_t;
+
+static inline struct task_group *next_task_group(struct task_group *tg)
+{
+ do {
+ tg = list_entry_rcu(tg->list.next,
+ typeof(struct task_group), list);
+ } while (&tg->list != &task_groups && task_group_is_autogroup(tg));
+
+ if (&tg->list == &task_groups)
+ tg = NULL;
+
+ return tg;
+}
+
+#define for_each_rt_rq(rt_rq, iter, rq) \
+ for (iter = container_of(&task_groups, typeof(*iter), list); \
+ (iter = next_task_group(iter)) && \
+ (rt_rq = iter->rt_rq[cpu_of(rq)]);)
+
+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)
static void sched_rt_rq_enqueue(struct rt_rq *rt_rq)
{
- int this_cpu = smp_processor_id();
struct task_struct *curr = rq_of_rt_rq(rt_rq)->curr;
struct sched_rt_entity *rt_se;
- rt_se = rt_rq->tg->rt_se[this_cpu];
+ 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))
static void sched_rt_rq_dequeue(struct rt_rq *rt_rq)
{
- int this_cpu = smp_processor_id();
struct sched_rt_entity *rt_se;
+ int cpu = cpu_of(rq_of_rt_rq(rt_rq));
- rt_se = rt_rq->tg->rt_se[this_cpu];
+ rt_se = rt_rq->tg->rt_se[cpu];
if (rt_se && on_rt_rq(rt_se))
dequeue_rt_entity(rt_se);
return ktime_to_ns(def_rt_bandwidth.rt_period);
}
+typedef struct rt_rq *rt_rq_iter_t;
+
+#define for_each_rt_rq(rt_rq, iter, rq) \
+ for ((void) iter, rt_rq = &rq->rt; rt_rq; rt_rq = NULL)
+
+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)
static void __disable_runtime(struct rq *rq)
{
struct root_domain *rd = rq->rd;
+ rt_rq_iter_t iter;
struct rt_rq *rt_rq;
if (unlikely(!scheduler_running))
return;
- for_each_leaf_rt_rq(rt_rq, rq) {
+ for_each_rt_rq(rt_rq, iter, rq) {
struct rt_bandwidth *rt_b = sched_rt_bandwidth(rt_rq);
s64 want;
int i;
static void __enable_runtime(struct rq *rq)
{
+ rt_rq_iter_t iter;
struct rt_rq *rt_rq;
if (unlikely(!scheduler_running))
/*
* Reset each runqueue's bandwidth settings
*/
- for_each_leaf_rt_rq(rt_rq, rq) {
+ for_each_rt_rq(rt_rq, iter, rq) {
struct rt_bandwidth *rt_b = sched_rt_bandwidth(rt_rq);
raw_spin_lock(&rt_b->rt_runtime_lock);
if (rt_rq->rt_throttled && rt_rq->rt_time < runtime) {
rt_rq->rt_throttled = 0;
enqueue = 1;
+
+ /*
+ * Force a clock update if the CPU was idle,
+ * lest wakeup -> unthrottle time accumulate.
+ */
+ if (rt_rq->rt_nr_running && rq->curr == rq->idle)
+ rq->skip_clock_update = -1;
}
if (rt_rq->rt_time || rt_rq->rt_nr_running)
idle = 0;
raw_spin_unlock(&rt_rq->rt_runtime_lock);
- } else if (rt_rq->rt_nr_running)
+ } else if (rt_rq->rt_nr_running) {
idle = 0;
+ if (!rt_rq_throttled(rt_rq))
+ enqueue = 1;
+ }
if (enqueue)
sched_rt_rq_enqueue(rt_rq);
struct rt_rq *rt_rq = rt_rq_of_se(rt_se);
u64 delta_exec;
- if (!task_has_rt_policy(curr))
+ if (curr->sched_class != &rt_sched_class)
return;
- delta_exec = rq->clock - curr->se.exec_start;
+ delta_exec = rq->clock_task - curr->se.exec_start;
if (unlikely((s64)delta_exec < 0))
delta_exec = 0;
curr->se.sum_exec_runtime += delta_exec;
account_group_exec_runtime(curr, delta_exec);
- curr->se.exec_start = rq->clock;
+ curr->se.exec_start = rq->clock_task;
cpuacct_charge(curr, delta_exec);
sched_rt_avg_update(rq, delta_exec);
if (group_rq && (rt_rq_throttled(group_rq) || !group_rq->rt_nr_running))
return;
+ if (!rt_rq->rt_nr_running)
+ list_add_leaf_rt_rq(rt_rq);
+
if (head)
list_add(&rt_se->run_list, queue);
else
__clear_bit(rt_se_prio(rt_se), array->bitmap);
dec_rt_tasks(rt_se, rt_rq);
+ if (!rt_rq->rt_nr_running)
+ list_del_leaf_rt_rq(rt_rq);
}
/*
static int find_lowest_rq(struct task_struct *task);
static int
-select_task_rq_rt(struct rq *rq, struct task_struct *p, int sd_flag, int flags)
+select_task_rq_rt(struct task_struct *p, int sd_flag, int flags)
{
+ struct task_struct *curr;
+ struct rq *rq;
+ int cpu;
+
if (sd_flag != SD_BALANCE_WAKE)
return smp_processor_id();
+ cpu = task_cpu(p);
+ rq = cpu_rq(cpu);
+
+ rcu_read_lock();
+ curr = ACCESS_ONCE(rq->curr); /* unlocked access */
+
/*
- * If the current task is an RT task, then
+ * If the current task on @p's runqueue is an RT task, then
* try to see if we can wake this RT task up on another
* runqueue. Otherwise simply start this RT task
* on its current runqueue.
* lock?
*
* For equal prio tasks, we just let the scheduler sort it out.
+ *
+ * Otherwise, just let it ride on the affined RQ and the
+ * post-schedule router will push the preempted task away
+ *
+ * This test is optimistic, if we get it wrong the load-balancer
+ * will have to sort it out.
*/
- if (unlikely(rt_task(rq->curr)) &&
- (rq->curr->rt.nr_cpus_allowed < 2 ||
- rq->curr->prio < p->prio) &&
+ if (curr && unlikely(rt_task(curr)) &&
+ (curr->rt.nr_cpus_allowed < 2 ||
+ curr->prio <= p->prio) &&
(p->rt.nr_cpus_allowed > 1)) {
- int cpu = find_lowest_rq(p);
+ int target = find_lowest_rq(p);
- return (cpu == -1) ? task_cpu(p) : cpu;
+ if (target != -1)
+ cpu = target;
}
+ rcu_read_unlock();
- /*
- * Otherwise, just let it ride on the affined RQ and the
- * post-schedule router will push the preempted task away
- */
- return task_cpu(p);
+ return cpu;
}
static void check_preempt_equal_prio(struct rq *rq, struct task_struct *p)
* to move current somewhere else, making room for our non-migratable
* task.
*/
- if (p->prio == rq->curr->prio && !need_resched())
+ if (p->prio == rq->curr->prio && !test_tsk_need_resched(rq->curr))
check_preempt_equal_prio(rq, p);
#endif
}
rt_rq = &rq->rt;
- if (unlikely(!rt_rq->rt_nr_running))
+ if (!rt_rq->rt_nr_running)
return NULL;
if (rt_rq_throttled(rt_rq))
} while (rt_rq);
p = rt_task_of(rt_se);
- p->se.exec_start = rq->clock;
+ p->se.exec_start = rq->clock_task;
return p;
}
* The previous task needs to be made eligible for pushing
* if it is still active
*/
- if (p->se.on_rq && p->rt.nr_cpus_allowed > 1)
+ if (on_rt_rq(&p->rt) && p->rt.nr_cpus_allowed > 1)
enqueue_pushable_task(rq, p);
}
int this_cpu = smp_processor_id();
int cpu = task_cpu(task);
+ /* Make sure the mask is initialized first */
+ if (unlikely(!lowest_mask))
+ return -1;
+
if (task->rt.nr_cpus_allowed == 1)
return -1; /* No other targets possible */
if (!cpumask_test_cpu(this_cpu, lowest_mask))
this_cpu = -1; /* Skip this_cpu opt if not among lowest */
+ rcu_read_lock();
for_each_domain(cpu, sd) {
if (sd->flags & SD_WAKE_AFFINE) {
int best_cpu;
* remote processor.
*/
if (this_cpu != -1 &&
- cpumask_test_cpu(this_cpu, sched_domain_span(sd)))
+ cpumask_test_cpu(this_cpu, sched_domain_span(sd))) {
+ rcu_read_unlock();
return this_cpu;
+ }
best_cpu = cpumask_first_and(lowest_mask,
sched_domain_span(sd));
- if (best_cpu < nr_cpu_ids)
+ if (best_cpu < nr_cpu_ids) {
+ rcu_read_unlock();
return best_cpu;
+ }
}
}
+ rcu_read_unlock();
/*
* And finally, if there were no matches within the domains
!cpumask_test_cpu(lowest_rq->cpu,
&task->cpus_allowed) ||
task_running(rq, task) ||
- !task->se.on_rq)) {
+ !task->on_rq)) {
raw_spin_unlock(&lowest_rq->lock);
lowest_rq = NULL;
BUG_ON(task_current(rq, p));
BUG_ON(p->rt.nr_cpus_allowed <= 1);
- BUG_ON(!p->se.on_rq);
+ BUG_ON(!p->on_rq);
BUG_ON(!rt_task(p));
return p;
task = pick_next_pushable_task(rq);
if (task_cpu(next_task) == rq->cpu && task == next_task) {
/*
- * If we get here, the task hasnt moved at all, but
+ * If we get here, the task hasn't moved at all, but
* it has failed to push. We will not try again,
* since the other cpus will pull from us when they
* are ready.
*/
if (p && (p->prio < this_rq->rt.highest_prio.curr)) {
WARN_ON(p == src_rq->curr);
- WARN_ON(!p->se.on_rq);
+ WARN_ON(!p->on_rq);
/*
* There's a chance that p is higher in priority
/*
* We continue with the search, just in
* case there's an even higher prio task
- * in another runqueue. (low likelyhood
+ * in another runqueue. (low likelihood
* but possible)
*/
}
static void pre_schedule_rt(struct rq *rq, struct task_struct *prev)
{
/* Try to pull RT tasks here if we lower this rq's prio */
- if (unlikely(rt_task(prev)) && rq->rt.highest_prio.curr > prev->prio)
+ if (rq->rt.highest_prio.curr > prev->prio)
pull_rt_task(rq);
}
p->rt.nr_cpus_allowed > 1 &&
rt_task(rq->curr) &&
(rq->curr->rt.nr_cpus_allowed < 2 ||
- rq->curr->prio < p->prio))
+ rq->curr->prio <= p->prio))
push_rt_tasks(rq);
}
* Update the migration status of the RQ if we have an RT task
* which is running AND changing its weight value.
*/
- if (p->se.on_rq && (weight != p->rt.nr_cpus_allowed)) {
+ if (p->on_rq && (weight != p->rt.nr_cpus_allowed)) {
struct rq *rq = task_rq(p);
if (!task_current(rq, p)) {
* When switch from the rt queue, we bring ourselves to a position
* that we might want to pull RT tasks from other runqueues.
*/
-static void switched_from_rt(struct rq *rq, struct task_struct *p,
- int running)
+static void switched_from_rt(struct rq *rq, struct task_struct *p)
{
/*
* If there are other RT tasks then we will reschedule
* we may need to handle the pulling of RT tasks
* now.
*/
- if (!rq->rt.rt_nr_running)
+ if (p->on_rq && !rq->rt.rt_nr_running)
pull_rt_task(rq);
}
* with RT tasks. In this case we try to push them off to
* other runqueues.
*/
-static void switched_to_rt(struct rq *rq, struct task_struct *p,
- int running)
+static void switched_to_rt(struct rq *rq, struct task_struct *p)
{
int check_resched = 1;
* If that current running task is also an RT task
* then see if we can move to another run queue.
*/
- if (!running) {
+ if (p->on_rq && rq->curr != p) {
#ifdef CONFIG_SMP
if (rq->rt.overloaded && push_rt_task(rq) &&
/* Don't resched if we changed runqueues */
* Priority of the task has changed. This may cause
* us to initiate a push or pull.
*/
-static void prio_changed_rt(struct rq *rq, struct task_struct *p,
- int oldprio, int running)
+static void
+prio_changed_rt(struct rq *rq, struct task_struct *p, int oldprio)
{
- if (running) {
+ if (!p->on_rq)
+ return;
+
+ if (rq->curr == p) {
#ifdef CONFIG_SMP
/*
* If our priority decreases while running, we
{
struct task_struct *p = rq->curr;
- p->se.exec_start = rq->clock;
+ p->se.exec_start = rq->clock_task;
/* The running task is never eligible for pushing */
dequeue_pushable_task(rq, p);
static void print_rt_stats(struct seq_file *m, int cpu)
{
+ rt_rq_iter_t iter;
struct rt_rq *rt_rq;
rcu_read_lock();
- for_each_leaf_rt_rq(rt_rq, cpu_rq(cpu))
+ for_each_rt_rq(rt_rq, iter, cpu_rq(cpu))
print_rt_rq(m, cpu, rt_rq);
rcu_read_unlock();
}