sched: debug: show a weight tree

Print a tree of weights.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

kernel/sched_fair.c

@@ -1611,6 +1611,30 @@ static const struct sched_class fair_sched_class = {
 };
 
 #ifdef CONFIG_SCHED_DEBUG
+static void
+print_cfs_rq_tasks(struct seq_file *m, struct cfs_rq *cfs_rq, int depth)
+{
+	struct sched_entity *se;
+
+	if (!cfs_rq)
+		return;
+
+	list_for_each_entry_rcu(se, &cfs_rq->tasks, group_node) {
+		int i;
+
+		for (i = depth; i; i--)
+			seq_puts(m, "  ");
+
+		seq_printf(m, "%lu %s %lu\n",
+				se->load.weight,
+				entity_is_task(se) ? "T" : "G",
+				calc_delta_weight(SCHED_LOAD_SCALE, se)
+				);
+		if (!entity_is_task(se))
+			print_cfs_rq_tasks(m, group_cfs_rq(se), depth + 1);
+	}
+}
+
 static void print_cfs_stats(struct seq_file *m, int cpu)
 {
 	struct cfs_rq *cfs_rq;
@@ -1618,6 +1642,9 @@ static void print_cfs_stats(struct seq_file *m, int cpu)
 	rcu_read_lock();
 	for_each_leaf_cfs_rq(cpu_rq(cpu), cfs_rq)
 		print_cfs_rq(m, cpu, cfs_rq);
+
+	seq_printf(m, "\nWeight tree:\n");
+	print_cfs_rq_tasks(m, &cpu_rq(cpu)->cfs, 1);
 	rcu_read_unlock();
 }
 #endif