--- linux-2.6.3-ck1pre/kernel/sched.c	2004-02-16 16:35:59.438517683 +1100
+++ linux-2.6.3-ck1/kernel/sched.c	2004-02-16 16:50:40.548143342 +1100
@@ -1527,6 +1527,14 @@ void scheduler_tick(int user_ticks, int 
 			cpustat->iowait += sys_ticks;
 		else
 			cpustat->idle += sys_ticks;
+		/*
+		 * Check if an SMT task has been put to sleep for
+		 * priority reasons.
+		 */
+		if (rq->nr_running) {
+			resched_task(p);
+			goto out;
+		}
 		rebalance_tick(rq, 1);
 		return;
 	}
@@ -1685,6 +1693,20 @@ need_resched:
 		if (!rq->nr_running) {
 			next = rq->idle;
 			rq->expired_timestamp = 0;
+#ifdef CONFIG_SMP
+			if (SMT_ACTIVE) {
+				/*
+				 * If an SMT sibling task is sleeping due to
+				 * priority reasons wake it up now
+				 */
+				runqueue_t *smt_rq;
+				smt_rq = cpu_rq(cpu_sibling_map[(rq->cpu)]);
+
+				if (smt_rq->curr == smt_rq->idle &&
+					smt_rq->nr_running)
+						resched_task(smt_rq->idle);
+			}
+#endif
 			goto switch_tasks;
 		}
 	}
@@ -1705,6 +1727,44 @@ need_resched:
 	queue = array->queue + idx;
 	next = list_entry(queue->next, task_t, run_list);
 
+#ifdef CONFIG_SMP
+	if (SMT_ACTIVE) {
+		runqueue_t *smt_rq;
+		task_t *smt_curr;
+		
+		smt_rq = cpu_rq(cpu_sibling_map[(rq->cpu)]);
+		smt_curr = smt_rq->curr;
+
+		/*
+		 * If a user task with lower static priority than the
+		 * running task on the SMT sibling is trying
+		 * to schedule, delay it till there is proportionately less
+		 * timeslice left of the sibling task to prevent a lower
+		 * priority task from using an unfair proportion of the 
+		 * physical cpu's resources.
+		 */
+		if (next->mm && smt_curr->mm && !rt_task(next) && 
+			((next->static_prio > smt_curr->static_prio && 
+			(smt_curr->time_slice * SMT_SIBLING_IMPACT / 100) > 
+			task_timeslice(next)) || rt_task(smt_curr))) {
+				next = rq->idle;
+				goto switch_tasks;
+		}
+		
+		/*
+		 * Reschedule a lower priority task
+		 * on the SMT sibling, or wake it up if it has been
+		 * put to sleep for priority reasons.
+		 */
+		if ((smt_curr != smt_rq->idle && 
+			smt_curr->static_prio > next->static_prio) ||
+			(rt_task(next) && !rt_task(smt_curr)) ||
+			(smt_curr == smt_rq->idle && smt_rq->nr_running))
+				resched_task(smt_curr);
+
+	}
+#endif
+
 	if (next->activated > 0) {
 		unsigned long long delta = now - next->timestamp;