sched: clean up sched_domain_debug()

clean up sched_domain_debug().

this also shrinks the code a bit:

   text    data     bss     dec     hex filename
  50474    4306     480   55260    d7dc sched.o.before
  50404    4306     480   55190    d796 sched.o.after
Signed-off-by: Ingo Molnar <mingo@elte.hu>

kernel/sched.c

@@ -5617,52 +5617,38 @@ int nr_cpu_ids __read_mostly = NR_CPUS;
 EXPORT_SYMBOL(nr_cpu_ids);
 
 #ifdef CONFIG_SCHED_DEBUG
-static void sched_domain_debug(struct sched_domain *sd, int cpu)
-{
-	int level = 0;
 
-	if (!sd) {
-		printk(KERN_DEBUG "CPU%d attaching NULL sched-domain.\n", cpu);
-		return;
-	}
-
-	printk(KERN_DEBUG "CPU%d attaching sched-domain:\n", cpu);
-
-	do {
-		int i;
-		char str[NR_CPUS];
+static int sched_domain_debug_one(struct sched_domain *sd, int cpu, int level)
+{
 	struct sched_group *group = sd->groups;
 	cpumask_t groupmask;
+	char str[NR_CPUS];
 
 	cpumask_scnprintf(str, NR_CPUS, sd->span);
 	cpus_clear(groupmask);
 
-		printk(KERN_DEBUG);
-		for (i = 0; i < level + 1; i++)
-			printk(" ");
-		printk("domain %d: ", level);
+	printk(KERN_DEBUG "%*s domain %d: ", level, "", level);
 
 	if (!(sd->flags & SD_LOAD_BALANCE)) {
 		printk("does not load-balance\n");
 		if (sd->parent)
 			printk(KERN_ERR "ERROR: !SD_LOAD_BALANCE domain"
 					" has parent");
-			break;
+		return -1;
 	}
 
-		printk("span %s\n", str);
+	printk(KERN_CONT "span %s\n", str);
 
-		if (!cpu_isset(cpu, sd->span))
+	if (!cpu_isset(cpu, sd->span)) {
 		printk(KERN_ERR "ERROR: domain->span does not contain "
 				"CPU%d\n", cpu);
-		if (!cpu_isset(cpu, group->cpumask))
+	}
+	if (!cpu_isset(cpu, group->cpumask)) {
 		printk(KERN_ERR "ERROR: domain->groups does not contain"
 				" CPU%d\n", cpu);
+	}
 
-		printk(KERN_DEBUG);
-		for (i = 0; i < level + 2; i++)
-			printk(" ");
-		printk("groups:");
+	printk(KERN_DEBUG "%*s groups:", level + 1, "");
 	do {
 		if (!group) {
 			printk("\n");
@@ -5699,19 +5685,33 @@ static void sched_domain_debug(struct sched_domain *sd, int cpu)
 	printk(KERN_CONT "\n");
 
 	if (!cpus_equal(sd->span, groupmask))
-			printk(KERN_ERR "ERROR: groups don't span "
-					"domain->span\n");
-
-		level++;
-		sd = sd->parent;
-		if (!sd)
-			continue;
+		printk(KERN_ERR "ERROR: groups don't span domain->span\n");
 
-		if (!cpus_subset(groupmask, sd->span))
+	if (sd->parent && !cpus_subset(groupmask, sd->parent->span))
 		printk(KERN_ERR "ERROR: parent span is not a superset "
 			"of domain->span\n");
+	return 0;
+}
+
+static void sched_domain_debug(struct sched_domain *sd, int cpu)
+{
+	int level = 0;
+
+	if (!sd) {
+		printk(KERN_DEBUG "CPU%d attaching NULL sched-domain.\n", cpu);
+		return;
+	}
+
+	printk(KERN_DEBUG "CPU%d attaching sched-domain:\n", cpu);
 
-	} while (sd);
+	for (;;) {
+		if (sched_domain_debug_one(sd, cpu, level))
+			break;
+		level++;
+		sd = sd->parent;
+		if (!sd)
+			break;
+	}
 }
 #else
 # define sched_domain_debug(sd, cpu) do { } while (0)