diff --git a/src/eloop.c b/src/eloop.c
index eabfeb2..dafb0b2 100644
--- a/src/eloop.c
+++ b/src/eloop.c
@@ -1300,6 +1300,8 @@ int ev_fd_update(struct ev_fd *fd, int mask)
 
 	if (!fd)
 		return -EINVAL;
+	if (fd->mask == mask)
+		return 0;
 
 	omask = fd->mask;
 	fd->mask = mask;