Re: [v3 PATCH] mm: move_pages: return valid node id in status if the page is already on the target node

[Yang Shi]

On 12/5/19 11:45 AM, Christopher Lameter wrote:
> On Fri, 6 Dec 2019, Yang Shi wrote:
>
> > Felix Abecassis reports move_pages() would return random status if the
> > pages are already on the target node by the below test program:
> Looks ok.
>
> Acked-by: Christoph Lameter <cl@xxxxxxxxx>
>
> Nitpicks:
>
> > @@ -1553,7 +1555,7 @@ static int add_page_for_migration(struct mm_struct *mm, unsigned long addr,
> >   	if (PageHuge(page)) {
> >   		if (PageHead(page)) {
> >   			isolate_huge_page(page, pagelist);
> > -			err = 0;
> > +			err = 1;
> Add a meaningful constant instead of 1?

Since it just returns errno, 0 and 1 it sounds not worth a constant or enum.

> >   out:
> >   	up_read(&mm->mmap_sem);
> > +
> >   	return err;
> Dont do that.

Yes, my fat finger.