Linux Virtualization - May 2016 - [PATCH v5 02/12] mm: migrate: support non-lru movable page migration

On (05/09/16 11:20), Minchan Kim wrote:
[..]
> +++ b/include/linux/migrate.h
> @@ -32,11 +32,16 @@ extern char *migrate_reason_names[MR_TYPES];
>  
>  #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?

	-ss

On Mon, May 16, 2016 at 04:17:51PM +0900, Sergey Senozhatsky
wrote:
> On (05/09/16 11:20), Minchan Kim wrote:
> [..]
> > +++ b/include/linux/migrate.h
> > @@ -32,11 +32,16 @@ extern char *migrate_reason_names[MR_TYPES];
> >  
> >  #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.

Thanks for the review, Sergey!
> 
> 	-ss

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