diff --git a/cache-tree.c b/cache-tree.c
index b4215f7eb30968..8bc075e3365456 100644
--- a/cache-tree.c
+++ b/cache-tree.c
@@ -230,7 +230,7 @@ static void discard_unused_subtrees(struct cache_tree *it)
 	}
 }
 
-int cache_tree_fully_valid(struct cache_tree *it)
+static int cache_tree_fully_valid_1(struct cache_tree *it)
 {
 	int i;
 	if (!it)
@@ -238,7 +238,7 @@ int cache_tree_fully_valid(struct cache_tree *it)
 	if (it->entry_count < 0 || !repo_has_object_file(the_repository, &it->oid))
 		return 0;
 	for (i = 0; i < it->subtree_nr; i++) {
-		if (!cache_tree_fully_valid(it->down[i]->cache_tree))
+		if (!cache_tree_fully_valid_1(it->down[i]->cache_tree))
 			return 0;
 	}
 	return 1;
@@ -249,6 +249,17 @@ static int must_check_existence(const struct cache_entry *ce)
 	return !(repo_has_promisor_remote(the_repository) && ce_skip_worktree(ce));
 }
 
+int cache_tree_fully_valid(struct cache_tree *it)
+{
+	int result;
+
+	trace2_region_enter("cache_tree", "fully_valid", NULL);
+	result = cache_tree_fully_valid_1(it);
+	trace2_region_leave("cache_tree", "fully_valid", NULL);
+
+	return result;
+}
+
 static int update_one(struct cache_tree *it,
 		      struct cache_entry **cache,
 		      int entries,