update_rt_migration(rt_rq);
}
+static inline int has_pushable_tasks(struct rq *rq)
+{
+ return !plist_head_empty(&rq->rt.pushable_tasks);
+}
+
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);
+
+ /* Update the highest prio pushable task */
+ if (p->prio < rq->rt.highest_prio.next)
+ rq->rt.highest_prio.next = p->prio;
}
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);
+ /* Update the new highest prio pushable task */
+ if (has_pushable_tasks(rq)) {
+ p = plist_first_entry(&rq->rt.pushable_tasks,
+ struct task_struct, pushable_tasks);
+ rq->rt.highest_prio.next = p->prio;
+ } else
+ rq->rt.highest_prio.next = MAX_RT_PRIO;
}
#else
typedef struct task_group *rt_rq_iter_t;
-#define for_each_rt_rq(rt_rq, iter, rq) \
- for (iter = list_entry_rcu(task_groups.next, typeof(*iter), list); \
- (&iter->list != &task_groups) && \
- (rt_rq = iter->rt_rq[cpu_of(rq)]); \
- iter = list_entry_rcu(iter->list.next, typeof(*iter), list))
+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)
{
#if defined CONFIG_SMP
-static struct task_struct *pick_next_highest_task_rt(struct rq *rq, int cpu);
-
-static inline int next_prio(struct rq *rq)
-{
- struct task_struct *next = pick_next_highest_task_rt(rq, rq->cpu);
-
- if (next && rt_prio(next->prio))
- return next->prio;
- else
- return MAX_RT_PRIO;
-}
-
static void
inc_rt_prio_smp(struct rt_rq *rt_rq, int prio, int prev_prio)
{
struct rq *rq = rq_of_rt_rq(rt_rq);
- if (prio < prev_prio) {
-
- /*
- * If the new task is higher in priority than anything on the
- * run-queue, we know that the previous high becomes our
- * next-highest.
- */
- rt_rq->highest_prio.next = prev_prio;
-
- if (rq->online)
- cpupri_set(&rq->rd->cpupri, rq->cpu, prio);
-
- } else if (prio == rt_rq->highest_prio.curr)
- /*
- * If the next task is equal in priority to the highest on
- * the run-queue, then we implicitly know that the next highest
- * task cannot be any lower than current
- */
- rt_rq->highest_prio.next = prio;
- else if (prio < rt_rq->highest_prio.next)
- /*
- * Otherwise, we need to recompute next-highest
- */
- rt_rq->highest_prio.next = next_prio(rq);
+ if (rq->online && prio < prev_prio)
+ cpupri_set(&rq->rd->cpupri, rq->cpu, prio);
}
static void
{
struct rq *rq = rq_of_rt_rq(rt_rq);
- if (rt_rq->rt_nr_running && (prio <= rt_rq->highest_prio.next))
- rt_rq->highest_prio.next = next_prio(rq);
-
if (rq->online && rt_rq->highest_prio.curr != prev_prio)
cpupri_set(&rq->rd->cpupri, rq->cpu, rt_rq->highest_prio.curr);
}
if (!task_current(rq, p) && p->rt.nr_cpus_allowed > 1)
enqueue_pushable_task(rq, p);
+
+ inc_nr_running(rq);
}
static void dequeue_task_rt(struct rq *rq, struct task_struct *p, int flags)
dequeue_rt_entity(rt_se);
dequeue_pushable_task(rq, p);
+
+ dec_nr_running(rq);
}
/*
struct rq *rq;
int cpu;
- if (sd_flag != SD_BALANCE_WAKE)
- return smp_processor_id();
-
cpu = task_cpu(p);
+
+ /* For anything but wake ups, just return the task_cpu */
+ if (sd_flag != SD_BALANCE_WAKE && sd_flag != SD_BALANCE_FORK)
+ goto out;
+
rq = cpu_rq(cpu);
rcu_read_lock();
}
rcu_read_unlock();
+out:
return cpu;
}
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))
static void put_prev_task_rt(struct rq *rq, struct task_struct *p)
{
update_curr_rt(rq);
- p->se.exec_start = 0;
/*
* The previous task needs to be made eligible for pushing
{
struct task_struct *next_task;
struct rq *lowest_rq;
+ int ret = 0;
if (!rq->rt.overloaded)
return 0;
if (!lowest_rq) {
struct task_struct *task;
/*
- * find lock_lowest_rq releases rq->lock
+ * find_lock_lowest_rq releases rq->lock
* so it is possible that next_task has migrated.
*
* We need to make sure that the task is still on the same
task = pick_next_pushable_task(rq);
if (task_cpu(next_task) == rq->cpu && task == next_task) {
/*
- * 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.
+ * The task hasn't migrated, and is still the next
+ * eligible task, but we failed to find a run-queue
+ * to push it to. Do not retry in this case, since
+ * other cpus will pull from us when ready.
*/
- dequeue_pushable_task(rq, next_task);
goto out;
}
deactivate_task(rq, next_task, 0);
set_task_cpu(next_task, lowest_rq->cpu);
activate_task(lowest_rq, next_task, 0);
+ ret = 1;
resched_task(lowest_rq->curr);
out:
put_task_struct(next_task);
- return 1;
+ return ret;
}
static void push_rt_tasks(struct rq *rq)
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);
}
rcu_read_unlock();
}
#endif /* CONFIG_SCHED_DEBUG */
-