Re: [PATCH v5 02/12] mm: migrate: support non-lru movable page migration

Sergey Senozhatsky
2016-05-17T01:30:42Z

On (05/17/16 10:18), Minchan Kim wrote:
[..]
> > > #ifdef CONFIG_MIGRATION
> > >
> > > +extern int PageMovable(struct page *page);
> > > +extern void __SetPageMovable(struct page *page, struct address_space *mapping);
> > > +extern void __ClearPageMovable(struct page *page);
> > > extern void putback_movable_pages(struct list_head *l);
> > > extern int migrate_page(struct address_space *,
> > > struct page *, struct page *, enum migrate_mode);
> > > extern int migrate_pages(struct list_head *l, new_page_t new, free_page_t free,
> > > unsigned long private, enum migrate_mode mode, int reason);
> > > +extern bool isolate_movable_page(struct page *page, isolate_mode_t mode);
> > > +extern void putback_movable_page(struct page *page);
> > >
> > > extern int migrate_prep(void);
> > > extern int migrate_prep_local(void);
> >
> > given that some of Movable users can be built as modules, shouldn't
> > at least some of those symbols be exported via EXPORT_SYMBOL?
>
> Those functions aim for VM compaction so driver shouldn't use it.
> Only driver should be aware of are __SetPageMovable and __CleraPageMovable.
> I will export them.
>

and PageMovable(), probably?

zsmalloc():

VM_BUG_ON_PAGE(!PageMovable(page), page);

> Thanks for the review, Sergey!

no prob! sorry, I'm a bit slow and late here.

-ss