sched: reduce stack size requirements in kernel/sched.c

Impact: cleanup

  * use node_to_cpumask_ptr in place of node_to_cpumask to reduce stack
    requirements in sched.c
Signed-off-by: Mike Travis <travis@sgi.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

kernel/sched.c

@@ -6110,8 +6110,9 @@ static void move_task_off_dead_cpu(int dead_cpu, struct task_struct *p)
 
 	do {
 		/* On same node? */
-		mask = node_to_cpumask(cpu_to_node(dead_cpu));
-		cpus_and(mask, mask, p->cpus_allowed);
+		node_to_cpumask_ptr(pnodemask, cpu_to_node(dead_cpu));
+
+		cpus_and(mask, *pnodemask, p->cpus_allowed);
 		dest_cpu = any_online_cpu(mask);
 
 		/* On any allowed CPU? */
@@ -7098,9 +7099,9 @@ static int cpu_to_allnodes_group(int cpu, const cpumask_t *cpu_map,
 				 struct sched_group **sg, cpumask_t *nodemask)
 {
 	int group;
+	node_to_cpumask_ptr(pnodemask, cpu_to_node(cpu));
 
-	*nodemask = node_to_cpumask(cpu_to_node(cpu));
-	cpus_and(*nodemask, *nodemask, *cpu_map);
+	cpus_and(*nodemask, *pnodemask, *cpu_map);
 	group = first_cpu(*nodemask);
 
 	if (sg)
@@ -7150,9 +7151,9 @@ static void free_sched_groups(const cpumask_t *cpu_map, cpumask_t *nodemask)
 
 		for (i = 0; i < nr_node_ids; i++) {
 			struct sched_group *oldsg, *sg = sched_group_nodes[i];
+			node_to_cpumask_ptr(pnodemask, i);
 
-			*nodemask = node_to_cpumask(i);
-			cpus_and(*nodemask, *nodemask, *cpu_map);
+			cpus_and(*nodemask, *pnodemask, *cpu_map);
 			if (cpus_empty(*nodemask))
 				continue;