> Is it possible to put the [patch 09/15] and [patch 10/15] together? They
> have similar changes.

Sure.

>
> Similarly, recursive function again. I have one question about it: how does
> it affect the performance when the recursion is deep enough? If it is not
> too deep, that should be good.

As I wrote in 09/15, it just looks recursive.

The depth is 2 at most.