[PATCH] setscheduler resched bug

[Joe Korty <joe.korty@ccur.com>]

setscheduler is not forcing a reschedule when needed like set_user_nice
does.  It should.

Joe


--- 2.5.69/kernel/sched.c.orig	2003-05-21 14:50:53.000000000 -0400
+++ 2.5.69/kernel/sched.c	2003-05-21 15:01:13.000000000 -0400
@@ -1716,6 +1716,7 @@
 	unsigned long flags;
 	runqueue_t *rq;
 	task_t *p;
+	int oldprio;
 
 	if (!param || pid < 0)
 		goto out_nounlock;
@@ -1778,12 +1779,20 @@
 	retval = 0;
 	p->policy = policy;
 	p->rt_priority = lp.sched_priority;
+	oldprio = p->prio;
 	if (policy != SCHED_NORMAL)
 		p->prio = MAX_USER_RT_PRIO-1 - p->rt_priority;
 	else
 		p->prio = p->static_prio;
-	if (array)
+	if (array) {
 		__activate_task(p, task_rq(p));
+		/*
+		 * Reschedule if on a CPU and the priority dropped, or not on
+		 * a CPU and the priority rose above the currently running task.
+		 */
+		if ((rq->curr == p) ? (p->prio > oldprio) : (p->prio < rq->curr->prio))
+			resched_task(rq->curr);
+	}
 
 out_unlock:
 	task_rq_unlock(rq, &flags);