Re: [PATCH 01/11] mm/page_isolation: prefer the node of the source page

[Joonsoo Kim <js1304@gmail.com>]

2020년 5월 21일 (목) 오전 9:37, Roman Gushchin <guro@fb.com>님이 작성:
>
> On Mon, May 18, 2020 at 10:20:47AM +0900, js1304@gmail.com wrote:
> > From: Joonsoo Kim <iamjoonsoo.kim@lge.com>
> >
> > For locality, it's better to migrate the page to the same node
> > rather than the node of the current caller's cpu.
> >
> > Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
>
> Acked-by: Roman Gushchin <guro@fb.com>

Thanks for review!

> > ---
> >  mm/page_isolation.c | 4 +++-
> >  1 file changed, 3 insertions(+), 1 deletion(-)
> >
> > diff --git a/mm/page_isolation.c b/mm/page_isolation.c
> > index 2c11a38..7df89bd 100644
> > --- a/mm/page_isolation.c
> > +++ b/mm/page_isolation.c
> > @@ -300,5 +300,7 @@ int test_pages_isolated(unsigned long start_pfn, unsigned long end_pfn,
> >
> >  struct page *alloc_migrate_target(struct page *page, unsigned long private)
> >  {
> > -     return new_page_nodemask(page, numa_node_id(), &node_states[N_MEMORY]);
> > +     int nid = page_to_nid(page);
> > +
> > +     return new_page_nodemask(page, nid, &node_states[N_MEMORY]);
>
> Why not new_page_nodemask(page, page_to_nid(page), &node_states[N_MEMORY]) ?
> Still fits into 80 characters.

It's just my preference not directly using function call in argument
as much as possible.
If you don't like it, I will change it as you suggested. However,
since alloc_migrate_target()
will be removed in following patch, there will be no difference in the end.

Thanks.