rbtree/test: test rbtree_postorder_for_each_entry_safe()

Signed-off-by: Cody P Schafer <cody@linux.vnet.ibm.com>
Cc: Michel Lespinasse <walken@google.com>
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

lib/rbtree_test.c

@@ -114,6 +114,16 @@ static int black_path_count(struct rb_node *rb)
 	return count;
 }
 
+static void check_postorder_foreach(int nr_nodes)
+{
+	struct test_node *cur, *n;
+	int count = 0;
+	rbtree_postorder_for_each_entry_safe(cur, n, &root, rb)
+		count++;
+
+	WARN_ON_ONCE(count != nr_nodes);
+}
+
 static void check_postorder(int nr_nodes)
 {
 	struct rb_node *rb;
@@ -148,6 +158,7 @@ static void check(int nr_nodes)
 	WARN_ON_ONCE(count < (1 << black_path_count(rb_last(&root))) - 1);
 
 	check_postorder(nr_nodes);
+	check_postorder_foreach(nr_nodes);
 }
 
 static void check_augmented(int nr_nodes)