[GIT PULL] scheduler fixes

Ingo Molnar
2009-01-15T22:53:01Z

Linus,

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

git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip.git sched-fixes-for-linus

Thanks,

Ingo

------------------>
Ingo Molnar (1):
Revert "sched: improve preempt debugging"

Lin Ming (1):
sched: sched_slice() fixlet

Peter Zijlstra (4):
sched: fix bandwidth validation for UID grouping
sched: SCHED_IDLE weight change
sched: SCHED_OTHER vs SCHED_IDLE isolation
sched: fix update_min_vruntime

kernel/sched.c | 13 ++++++++++---
kernel/sched_fair.c | 37 +++++++++++++++++++++++++++----------
2 files changed, 37 insertions(+), 13 deletions(-)

diff --git a/kernel/sched.c b/kernel/sched.c
index 8be2c13..6acfb3c 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -1323,8 +1323,8 @@ static inline void update_load_sub(struct load_weight *lw, unsigned long dec)
* slice expiry etc.
*/

-#define WEIGHT_IDLEPRIO 2
-#define WMULT_IDLEPRIO (1 << 31)
+#define WEIGHT_IDLEPRIO 3
+#define WMULT_IDLEPRIO 1431655765

/*
* Nice levels are multiplicative, with a gentle 10% change for every
@@ -4440,7 +4440,7 @@ void __kprobes sub_preempt_count(int val)
/*
* Underflow?
*/
- if (DEBUG_LOCKS_WARN_ON(val > preempt_count() - (!!kernel_locked())))
+ if (DEBUG_LOCKS_WARN_ON(val > preempt_count()))
return;
/*
* Is the spinlock portion underflowing?
@@ -9050,6 +9050,13 @@ static int tg_schedulable(struct task_group *tg, void *data)
runtime = d->rt_runtime;
}

+#ifdef CONFIG_USER_SCHED
+ if (tg == &root_task_group) {
+ period = global_rt_period();
+ runtime = global_rt_runtime();
+ }
+#endif
+
/*
* Cannot have more runtime than the period.
*/
diff --git a/kernel/sched_fair.c b/kernel/sched_fair.c
index 8e1352c..5cc1c16 100644
--- a/kernel/sched_fair.c
+++ b/kernel/sched_fair.c
@@ -283,7 +283,7 @@ static void update_min_vruntime(struct cfs_rq *cfs_rq)
struct sched_entity,
run_node);

- if (vruntime == cfs_rq->min_vruntime)
+ if (!cfs_rq->curr)
vruntime = se->vruntime;
else
vruntime = min_vruntime(vruntime, se->vruntime);
@@ -429,7 +429,10 @@ static u64 sched_slice(struct cfs_rq *cfs_rq, struct sched_entity *se)
u64 slice = __sched_period(cfs_rq->nr_running + !se->on_rq);

for_each_sched_entity(se) {
- struct load_weight *load = &cfs_rq->load;
+ struct load_weight *load;
+
+ cfs_rq = cfs_rq_of(se);
+ load = &cfs_rq->load;

if (unlikely(!se->on_rq)) {
struct load_weight lw = cfs_rq->load;
@@ -677,9 +680,13 @@ place_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int initial)
unsigned long thresh = sysctl_sched_latency;

/*
- * convert the sleeper threshold into virtual time
+ * Convert the sleeper threshold into virtual time.
+ * SCHED_IDLE is a special sub-class. We care about
+ * fairness only relative to other SCHED_IDLE tasks,
+ * all of which have the same weight.
*/
- if (sched_feat(NORMALIZED_SLEEPER))
+ if (sched_feat(NORMALIZED_SLEEPER) &&
+ task_of(se)->policy != SCHED_IDLE)
thresh = calc_delta_fair(thresh, se);

vruntime -= thresh;
@@ -1340,14 +1347,18 @@ wakeup_preempt_entity(struct sched_entity *curr, struct sched_entity *se)

static void set_last_buddy(struct sched_entity *se)
{
- for_each_sched_entity(se)
- cfs_rq_of(se)->last = se;
+ if (likely(task_of(se)->policy != SCHED_IDLE)) {
+ for_each_sched_entity(se)
+ cfs_rq_of(se)->last = se;
+ }
}

static void set_next_buddy(struct sched_entity *se)
{
- for_each_sched_entity(se)
- cfs_rq_of(se)->next = se;
+ if (likely(task_of(se)->policy != SCHED_IDLE)) {
+ for_each_sched_entity(se)
+ cfs_rq_of(se)->next = se;
+ }
}

/*
@@ -1393,12 +1404,18 @@ static void check_preempt_wakeup(struct rq *rq, struct task_struct *p, int sync)
return;

/*
- * Batch tasks do not preempt (their preemption is driven by
+ * Batch and idle tasks do not preempt (their preemption is driven by
* the tick):
*/
- if (unlikely(p->policy == SCHED_BATCH))
+ if (unlikely(p->policy != SCHED_NORMAL))
return;

+ /* Idle tasks are by definition preempted by everybody. */
+ if (unlikely(curr->policy == SCHED_IDLE)) {
+ resched_task(curr);
+ return;
+ }
+
if (!sched_feat(WAKEUP_PREEMPT))
return;