--- linux-2.6.0-test11-batch-4/kernel/sched.c	2003-12-16 00:34:51.115494522 +1100
+++ linux-2.6.0-test11-ck2/kernel/sched.c	2003-12-16 00:09:08.597055914 +1100
@@ -37,6 +37,7 @@
 #include <linux/rcupdate.h>
 #include <linux/cpu.h>
 #include <linux/percpu.h>
+#include <linux/list.h> 
 
 #ifdef CONFIG_NUMA
 #define cpu_to_node_mask(cpu) node_to_cpumask(cpu_to_node(cpu))
@@ -357,6 +358,59 @@ static inline void enqueue_task(struct t
 	p->array = array;
 }
 
+/* idle balancing infrastructure */
+struct idle_cpus_list {
+	spinlock_t lock;
+	struct list_head list;
+};
+
+struct idle_cpu {
+	struct list_head list;
+	int cpuid;
+};
+
+DEFINE_PER_CPU(struct idle_cpu, cpu_is_idle);
+/* global idle cpu list */
+struct idle_cpus_list idle_list;
+
+static void set_cpu_idle(struct idle_cpus_list* ic, int cpu)
+{
+        spin_lock(&ic->lock);
+
+	list_add(&per_cpu(cpu_is_idle, cpu).list, &ic->list);
+
+        spin_unlock(&ic->lock);
+}
+
+static inline void set_cpu_not_idle(struct idle_cpus_list* ic, int cpu)
+{
+        spin_lock(&ic->lock);
+
+	list_del(&per_cpu(cpu_is_idle, cpu).list);
+
+        spin_unlock(&ic->lock);
+}
+
+/* return the ID of the idlest cpu */
+/* -1 if no CPU is idle */
+static int idlest_cpu(struct idle_cpus_list* ic)
+{
+        struct idle_cpu* cpu;
+
+        spin_lock(&ic->lock);
+
+        if (list_empty(&ic->list)) {
+		spin_unlock(&ic->lock);
+                return NR_CPUS + 1;
+	}
+
+	cpu = list_entry(ic->list.next, struct idle_cpu, list);
+
+        spin_unlock(&ic->lock);
+
+        return cpu->cpuid;
+}
+
 /*
  * effective_prio - return the priority that is based on the static
  * priority but is modified by bonuses/penalties.
@@ -389,6 +443,8 @@ static int effective_prio(task_t *p)
 	return prio;
 }
 
+static inline void resched_task(task_t *p);
+
 /*
  * __activate_task - move a task to the runqueue.
  */
@@ -401,6 +457,13 @@ static inline void __activate_task(task_
 		enqueue_task(p, rq->active);
 
 	nr_running_inc(rq);
+#ifdef CONFIG_SMP
+	if (rq->nr_running > 1){
+		unsigned long cpu = idlest_cpu(&idle_list);
+		if (cpu <= NR_CPUS)
+			resched_task(cpu_rq(cpu)->idle);
+	}
+#endif
 }
 
 static void recalc_task_prio(task_t *p, unsigned long long now)
@@ -1441,7 +1504,6 @@ void scheduler_tick(int user_ticks, int 
 			resched_task(p);
 			goto out;
 		}
-		rebalance_tick(rq, 1);
 		return;
 	}
 
@@ -1706,6 +1768,12 @@ switch_tasks:
 		rq->nr_switches++;
 		rq->curr = next;
 
+		if (unlikely(next == rq->idle))
+			set_cpu_idle(&idle_list, rq->cpu);
+		else
+			if (prev == rq->idle)
+				set_cpu_not_idle(&idle_list, rq->cpu);
+
 		prepare_arch_switch(rq, next);
 		prev = context_switch(rq, prev, next);
 		barrier();
@@ -2925,6 +2993,24 @@ __init static void init_kstat(void) {
 	register_cpu_notifier(&kstat_nb);
 }
 
+static void init_idle_cpus_list(struct idle_cpus_list* ic)
+{
+	int i;
+
+        memset(ic, 0, sizeof(*ic));
+
+        spin_lock_init(&ic->lock);
+
+        /* no CPU is currently idle */
+        INIT_LIST_HEAD(&ic->list);
+
+	/* initialize the per cpu list of idle_cpu structs */
+	for (i = 0; i < NR_CPUS; ++i) {
+		INIT_LIST_HEAD(&per_cpu(cpu_is_idle, i).list);
+		per_cpu(cpu_is_idle, i).cpuid = i;
+	}
+}
+
 void __init sched_init(void)
 {
 	runqueue_t *rq;
@@ -2932,6 +3018,8 @@ void __init sched_init(void)
 
 	/* Init the kstat counters */
 	init_kstat();
+	init_idle_cpus_list(&idle_list);
+
 	for (i = 0; i < NR_CPUS; i++) {
 		prio_array_t *array;