From 24813c909f98b298aed8bde7663cfe79ada9555b Mon Sep 17 00:00:00 2001
From: Gregory Haskins <ghaskins@novell.com>
Date: Fri, 25 Jan 2008 21:08:12 +0100
Subject: [PATCH] --- yaml --- r: 76137 b: refs/heads/master c:
 a22d7fc187ed996b66d8439db27b2303f79a8e7b h: refs/heads/master i:   76135:
 998e08f4c327d3687326e31983133dbd57affce9 v: v3

---
 [refs]                  |  2 +-
 trunk/kernel/sched.c    |  2 ++
 trunk/kernel/sched_rt.c | 10 ++++++++--
 3 files changed, 11 insertions(+), 3 deletions(-)

diff --git a/[refs] b/[refs]
index 874ff35eebf9..3b62cb9b62e8 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 6e1254d2c41215da27025add8900ed187bca121d
+refs/heads/master: a22d7fc187ed996b66d8439db27b2303f79a8e7b
diff --git a/trunk/kernel/sched.c b/trunk/kernel/sched.c
index 3344ba776b97..c591abd9ca38 100644
--- a/trunk/kernel/sched.c
+++ b/trunk/kernel/sched.c
@@ -346,6 +346,7 @@ struct rt_rq {
 	unsigned long rt_nr_migratory;
 	/* highest queued rt task prio */
 	int highest_prio;
+	int overloaded;
 };
 
 /*
@@ -6770,6 +6771,7 @@ void __init sched_init(void)
 		rq->migration_thread = NULL;
 		INIT_LIST_HEAD(&rq->migration_queue);
 		rq->rt.highest_prio = MAX_RT_PRIO;
+		rq->rt.overloaded = 0;
 #endif
 		atomic_set(&rq->nr_iowait, 0);
 
diff --git a/trunk/kernel/sched_rt.c b/trunk/kernel/sched_rt.c
index a9d7d4408160..87d7b3ff3861 100644
--- a/trunk/kernel/sched_rt.c
+++ b/trunk/kernel/sched_rt.c
@@ -16,6 +16,7 @@ static inline cpumask_t *rt_overload(void)
 }
 static inline void rt_set_overload(struct rq *rq)
 {
+	rq->rt.overloaded = 1;
 	cpu_set(rq->cpu, rt_overload_mask);
 	/*
 	 * Make sure the mask is visible before we set
@@ -32,6 +33,7 @@ static inline void rt_clear_overload(struct rq *rq)
 	/* the order here really doesn't matter */
 	atomic_dec(&rto_count);
 	cpu_clear(rq->cpu, rt_overload_mask);
+	rq->rt.overloaded = 0;
 }
 
 static void update_rt_migration(struct rq *rq)
@@ -448,6 +450,9 @@ static int push_rt_task(struct rq *rq)
 
 	assert_spin_locked(&rq->lock);
 
+	if (!rq->rt.overloaded)
+		return 0;
+
 	next_task = pick_next_highest_task_rt(rq, -1);
 	if (!next_task)
 		return 0;
@@ -675,7 +680,7 @@ static void schedule_tail_balance_rt(struct rq *rq)
 	 * the lock was owned by prev, we need to release it
 	 * first via finish_lock_switch and then reaquire it here.
 	 */
-	if (unlikely(rq->rt.rt_nr_running > 1)) {
+	if (unlikely(rq->rt.overloaded)) {
 		spin_lock_irq(&rq->lock);
 		push_rt_tasks(rq);
 		spin_unlock_irq(&rq->lock);
@@ -687,7 +692,8 @@ static void wakeup_balance_rt(struct rq *rq, struct task_struct *p)
 {
 	if (unlikely(rt_task(p)) &&
 	    !task_running(rq, p) &&
-	    (p->prio >= rq->curr->prio))
+	    (p->prio >= rq->rt.highest_prio) &&
+	    rq->rt.overloaded)
 		push_rt_tasks(rq);
 }