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-rw-r--r--kernel/sched/fair.c56
1 files changed, 28 insertions, 28 deletions
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 8bc0a883d190..70ba32e08a23 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -513,6 +513,7 @@ static inline int entity_before(struct sched_entity *a,
static void update_min_vruntime(struct cfs_rq *cfs_rq)
{
struct sched_entity *curr = cfs_rq->curr;
+ struct rb_node *leftmost = rb_first_cached(&cfs_rq->tasks_timeline);
u64 vruntime = cfs_rq->min_vruntime;
@@ -523,10 +524,9 @@ static void update_min_vruntime(struct cfs_rq *cfs_rq)
curr = NULL;
}
- if (cfs_rq->rb_leftmost) {
- struct sched_entity *se = rb_entry(cfs_rq->rb_leftmost,
- struct sched_entity,
- run_node);
+ if (leftmost) { /* non-empty tree */
+ struct sched_entity *se;
+ se = rb_entry(leftmost, struct sched_entity, run_node);
if (!curr)
vruntime = se->vruntime;
@@ -547,10 +547,10 @@ static void update_min_vruntime(struct cfs_rq *cfs_rq)
*/
static void __enqueue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se)
{
- struct rb_node **link = &cfs_rq->tasks_timeline.rb_node;
+ struct rb_node **link = &cfs_rq->tasks_timeline.rb_root.rb_node;
struct rb_node *parent = NULL;
struct sched_entity *entry;
- int leftmost = 1;
+ bool leftmost = true;
/*
* Find the right place in the rbtree:
@@ -566,36 +566,23 @@ static void __enqueue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se)
link = &parent->rb_left;
} else {
link = &parent->rb_right;
- leftmost = 0;
+ leftmost = false;
}
}
- /*
- * Maintain a cache of leftmost tree entries (it is frequently
- * used):
- */
- if (leftmost)
- cfs_rq->rb_leftmost = &se->run_node;
-
rb_link_node(&se->run_node, parent, link);
- rb_insert_color(&se->run_node, &cfs_rq->tasks_timeline);
+ rb_insert_color_cached(&se->run_node,
+ &cfs_rq->tasks_timeline, leftmost);
}
static void __dequeue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se)
{
- if (cfs_rq->rb_leftmost == &se->run_node) {
- struct rb_node *next_node;
-
- next_node = rb_next(&se->run_node);
- cfs_rq->rb_leftmost = next_node;
- }
-
- rb_erase(&se->run_node, &cfs_rq->tasks_timeline);
+ rb_erase_cached(&se->run_node, &cfs_rq->tasks_timeline);
}
struct sched_entity *__pick_first_entity(struct cfs_rq *cfs_rq)
{
- struct rb_node *left = cfs_rq->rb_leftmost;
+ struct rb_node *left = rb_first_cached(&cfs_rq->tasks_timeline);
if (!left)
return NULL;
@@ -616,7 +603,7 @@ static struct sched_entity *__pick_next_entity(struct sched_entity *se)
#ifdef CONFIG_SCHED_DEBUG
struct sched_entity *__pick_last_entity(struct cfs_rq *cfs_rq)
{
- struct rb_node *last = rb_last(&cfs_rq->tasks_timeline);
+ struct rb_node *last = rb_last(&cfs_rq->tasks_timeline.rb_root);
if (!last)
return NULL;
@@ -5437,7 +5424,7 @@ wake_affine_llc(struct sched_domain *sd, struct task_struct *p,
return false;
/* if this cache has capacity, come here */
- if (this_stats.has_capacity && this_stats.nr_running < prev_stats.nr_running+1)
+ if (this_stats.has_capacity && this_stats.nr_running+1 < prev_stats.nr_running)
return true;
/*
@@ -7721,7 +7708,7 @@ next_group:
* number.
*
* Return: 1 when packing is required and a task should be moved to
- * this CPU. The amount of the imbalance is returned in *imbalance.
+ * this CPU. The amount of the imbalance is returned in env->imbalance.
*
* @env: The load balancing environment.
* @sds: Statistics of the sched_domain which is to be packed
@@ -8450,6 +8437,12 @@ static int idle_balance(struct rq *this_rq, struct rq_flags *rf)
this_rq->idle_stamp = rq_clock(this_rq);
/*
+ * Do not pull tasks towards !active CPUs...
+ */
+ if (!cpu_active(this_cpu))
+ return 0;
+
+ /*
* This is OK, because current is on_cpu, which avoids it being picked
* for load-balance and preemption/IRQs are still disabled avoiding
* further scheduler activity on it and we're being very careful to
@@ -8556,6 +8549,13 @@ static int active_load_balance_cpu_stop(void *data)
struct rq_flags rf;
rq_lock_irq(busiest_rq, &rf);
+ /*
+ * Between queueing the stop-work and running it is a hole in which
+ * CPUs can become inactive. We should not move tasks from or to
+ * inactive CPUs.
+ */
+ if (!cpu_active(busiest_cpu) || !cpu_active(target_cpu))
+ goto out_unlock;
/* make sure the requested cpu hasn't gone down in the meantime */
if (unlikely(busiest_cpu != smp_processor_id() ||
@@ -9312,7 +9312,7 @@ static void set_curr_task_fair(struct rq *rq)
void init_cfs_rq(struct cfs_rq *cfs_rq)
{
- cfs_rq->tasks_timeline = RB_ROOT;
+ cfs_rq->tasks_timeline = RB_ROOT_CACHED;
cfs_rq->min_vruntime = (u64)(-(1LL << 20));
#ifndef CONFIG_64BIT
cfs_rq->min_vruntime_copy = cfs_rq->min_vruntime;
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