[GIT PULL] scheduler fixes

Ingo Molnar
2014-03-03T16:29:16Z

Linus,

Please pull the latest sched-urgent-for-linus git tree from:

git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git sched-urgent-for-linus

# HEAD: faa5993736d9b44b508cab4f1f3a77d66641c6f4 sched/deadline: Prevent rt_time growth to infinity

Misc fixes, most of them SCHED_DEADLINE fallout.

Thanks,

Ingo

------------------>
George McCollister (1):
sched: Fix double normalization of vruntime

Juri Lelli (2):
sched/deadline: Switch CPU's presence test order
sched/deadline: Prevent rt_time growth to infinity

Kirill Tkhai (1):
sched/deadline: Cleanup RT leftovers from {inc/dec}_dl_migration

kernel/sched/cpudeadline.c | 4 ++--
kernel/sched/deadline.c | 10 ++++++----
kernel/sched/fair.c | 8 ++++----
kernel/sched/rt.c | 8 ++++++++
4 files changed, 20 insertions(+), 10 deletions(-)

diff --git a/kernel/sched/cpudeadline.c b/kernel/sched/cpudeadline.c
index 5b8838b..5b9bb42 100644
--- a/kernel/sched/cpudeadline.c
+++ b/kernel/sched/cpudeadline.c
@@ -70,7 +70,7 @@ static void cpudl_heapify(struct cpudl *cp, int idx)

static void cpudl_change_key(struct cpudl *cp, int idx, u64 new_dl)
{
- WARN_ON(!cpu_present(idx) || idx == IDX_INVALID);
+ WARN_ON(idx == IDX_INVALID || !cpu_present(idx));

if (dl_time_before(new_dl, cp->elements[idx].dl)) {
cp->elements[idx].dl = new_dl;
@@ -117,7 +117,7 @@ int cpudl_find(struct cpudl *cp, struct task_struct *p,
}

out:
- WARN_ON(!cpu_present(best_cpu) && best_cpu != -1);
+ WARN_ON(best_cpu != -1 && !cpu_present(best_cpu));

return best_cpu;
}
diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c
index 15cbc17..6e79b3f 100644
--- a/kernel/sched/deadline.c
+++ b/kernel/sched/deadline.c
@@ -135,7 +135,6 @@ static void update_dl_migration(struct dl_rq *dl_rq)
static void inc_dl_migration(struct sched_dl_entity *dl_se, struct dl_rq *dl_rq)
{
struct task_struct *p = dl_task_of(dl_se);
- dl_rq = &rq_of_dl_rq(dl_rq)->dl;

if (p->nr_cpus_allowed > 1)
dl_rq->dl_nr_migratory++;
@@ -146,7 +145,6 @@ static void inc_dl_migration(struct sched_dl_entity *dl_se, struct dl_rq *dl_rq)
static void dec_dl_migration(struct sched_dl_entity *dl_se, struct dl_rq *dl_rq)
{
struct task_struct *p = dl_task_of(dl_se);
- dl_rq = &rq_of_dl_rq(dl_rq)->dl;

if (p->nr_cpus_allowed > 1)
dl_rq->dl_nr_migratory--;
@@ -564,6 +562,8 @@ int dl_runtime_exceeded(struct rq *rq, struct sched_dl_entity *dl_se)
return 1;
}

+extern bool sched_rt_bandwidth_account(struct rt_rq *rt_rq);
+
/*
* Update the current task's runtime statistics (provided it is still
* a -deadline task and has not been removed from the dl_rq).
@@ -627,11 +627,13 @@ static void update_curr_dl(struct rq *rq)
struct rt_rq *rt_rq = &rq->rt;

raw_spin_lock(&rt_rq->rt_runtime_lock);
- rt_rq->rt_time += delta_exec;
/*
* We'll let actual RT tasks worry about the overflow here, we
- * have our own CBS to keep us inline -- see above.
+ * have our own CBS to keep us inline; only account when RT
+ * bandwidth is relevant.
*/
+ if (sched_rt_bandwidth_account(rt_rq))
+ rt_rq->rt_time += delta_exec;
raw_spin_unlock(&rt_rq->rt_runtime_lock);
}
}
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 7815709..9b4c4f3 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -7001,15 +7001,15 @@ static void switched_from_fair(struct rq *rq, struct task_struct *p)
struct cfs_rq *cfs_rq = cfs_rq_of(se);

/*
- * Ensure the task's vruntime is normalized, so that when its
+ * Ensure the task's vruntime is normalized, so that when it's
* switched back to the fair class the enqueue_entity(.flags=0) will
* do the right thing.
*
- * If it was on_rq, then the dequeue_entity(.flags=0) will already
- * have normalized the vruntime, if it was !on_rq, then only when
+ * If it's on_rq, then the dequeue_entity(.flags=0) will already
+ * have normalized the vruntime, if it's !on_rq, then only when
* the task is sleeping will it still have non-normalized vruntime.
*/
- if (!se->on_rq && p->state != TASK_RUNNING) {
+ if (!p->on_rq && p->state != TASK_RUNNING) {
/*
* Fix up our vruntime so that the current sleep doesn't
* cause 'unlimited' sleep bonus.
diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c
index a2740b7..1999021 100644
--- a/kernel/sched/rt.c
+++ b/kernel/sched/rt.c
@@ -538,6 +538,14 @@ static inline struct rt_bandwidth *sched_rt_bandwidth(struct rt_rq *rt_rq)

#endif /* CONFIG_RT_GROUP_SCHED */

+bool sched_rt_bandwidth_account(struct rt_rq *rt_rq)
+{
+ struct rt_bandwidth *rt_b = sched_rt_bandwidth(rt_rq);
+
+ return (hrtimer_active(&rt_b->rt_period_timer) ||
+ rt_rq->rt_time < rt_b->rt_runtime);
+}
+
#ifdef CONFIG_SMP
/*
* We ran out of runtime, see if we can borrow some from our neighbours.