diff --git a/lib/libthr/thread/thr_stack.c b/lib/libthr/thread/thr_stack.c
index f576a2c04104bb..d249bb5606fdfe 100644
--- a/lib/libthr/thread/thr_stack.c
+++ b/lib/libthr/thread/thr_stack.c
@@ -126,10 +126,7 @@ static char *last_stack = NULL;
 static inline size_t
 round_up(size_t size)
 {
-	if (size % _thr_page_size != 0)
-		size = ((size / _thr_page_size) + 1) *
-		    _thr_page_size;
-	return size;
+	return (roundup2(size, _thr_page_size));
 }
 
 void