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Diffstat (limited to 'kernel/sched.c')
-rw-r--r--kernel/sched.c57
1 files changed, 35 insertions, 22 deletions
diff --git a/kernel/sched.c b/kernel/sched.c
index 8ee437a5ec1d..8e2558c2ba67 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -223,7 +223,7 @@ static void start_rt_bandwidth(struct rt_bandwidth *rt_b)
{
ktime_t now;
- if (rt_bandwidth_enabled() && rt_b->rt_runtime == RUNTIME_INF)
+ if (!rt_bandwidth_enabled() || rt_b->rt_runtime == RUNTIME_INF)
return;
if (hrtimer_active(&rt_b->rt_period_timer))
@@ -2266,16 +2266,6 @@ static int try_to_wake_up(struct task_struct *p, unsigned int state, int sync)
if (!sched_feat(SYNC_WAKEUPS))
sync = 0;
- if (!sync) {
- if (current->se.avg_overlap < sysctl_sched_migration_cost &&
- p->se.avg_overlap < sysctl_sched_migration_cost)
- sync = 1;
- } else {
- if (current->se.avg_overlap >= sysctl_sched_migration_cost ||
- p->se.avg_overlap >= sysctl_sched_migration_cost)
- sync = 0;
- }
-
#ifdef CONFIG_SMP
if (sched_feat(LB_WAKEUP_UPDATE)) {
struct sched_domain *sd;
@@ -3890,19 +3880,24 @@ int select_nohz_load_balancer(int stop_tick)
int cpu = smp_processor_id();
if (stop_tick) {
- cpumask_set_cpu(cpu, nohz.cpu_mask);
cpu_rq(cpu)->in_nohz_recently = 1;
- /*
- * If we are going offline and still the leader, give up!
- */
- if (!cpu_active(cpu) &&
- atomic_read(&nohz.load_balancer) == cpu) {
+ if (!cpu_active(cpu)) {
+ if (atomic_read(&nohz.load_balancer) != cpu)
+ return 0;
+
+ /*
+ * If we are going offline and still the leader,
+ * give up!
+ */
if (atomic_cmpxchg(&nohz.load_balancer, cpu, -1) != cpu)
BUG();
+
return 0;
}
+ cpumask_set_cpu(cpu, nohz.cpu_mask);
+
/* time for ilb owner also to sleep */
if (cpumask_weight(nohz.cpu_mask) == num_online_cpus()) {
if (atomic_read(&nohz.load_balancer) == cpu)
@@ -6949,20 +6944,26 @@ static void free_rootdomain(struct root_domain *rd)
static void rq_attach_root(struct rq *rq, struct root_domain *rd)
{
+ struct root_domain *old_rd = NULL;
unsigned long flags;
spin_lock_irqsave(&rq->lock, flags);
if (rq->rd) {
- struct root_domain *old_rd = rq->rd;
+ old_rd = rq->rd;
if (cpumask_test_cpu(rq->cpu, old_rd->online))
set_rq_offline(rq);
cpumask_clear_cpu(rq->cpu, old_rd->span);
- if (atomic_dec_and_test(&old_rd->refcount))
- free_rootdomain(old_rd);
+ /*
+ * If we dont want to free the old_rt yet then
+ * set old_rd to NULL to skip the freeing later
+ * in this function:
+ */
+ if (!atomic_dec_and_test(&old_rd->refcount))
+ old_rd = NULL;
}
atomic_inc(&rd->refcount);
@@ -6973,6 +6974,9 @@ static void rq_attach_root(struct rq *rq, struct root_domain *rd)
set_rq_online(rq);
spin_unlock_irqrestore(&rq->lock, flags);
+
+ if (old_rd)
+ free_rootdomain(old_rd);
}
static int __init_refok init_rootdomain(struct root_domain *rd, bool bootmem)
@@ -9220,6 +9224,16 @@ static int sched_rt_global_constraints(void)
return ret;
}
+
+int sched_rt_can_attach(struct task_group *tg, struct task_struct *tsk)
+{
+ /* Don't accept realtime tasks when there is no way for them to run */
+ if (rt_task(tsk) && tg->rt_bandwidth.rt_runtime == 0)
+ return 0;
+
+ return 1;
+}
+
#else /* !CONFIG_RT_GROUP_SCHED */
static int sched_rt_global_constraints(void)
{
@@ -9313,8 +9327,7 @@ cpu_cgroup_can_attach(struct cgroup_subsys *ss, struct cgroup *cgrp,
struct task_struct *tsk)
{
#ifdef CONFIG_RT_GROUP_SCHED
- /* Don't accept realtime tasks when there is no way for them to run */
- if (rt_task(tsk) && cgroup_tg(cgrp)->rt_bandwidth.rt_runtime == 0)
+ if (!sched_rt_can_attach(cgroup_tg(cgrp), tsk))
return -EINVAL;
#else
/* We don't support RT-tasks being in separate groups */