Re: [PATCH v7 03/12] mm/sparsemem: Add helpers track active portions of a section at boot

[Oscar Salvador]

On Thu, May 02, 2019 at 07:03:45AM -0700, Dan Williams wrote:
> > section_active_mask() also converts the value to address/size.
> > Why do we need to convert the values and we cannot work with pfn/pages instead?
> > It should be perfectly possible unless I am missing something.
> >
> > The only thing required would be to export earlier your:
> >
> > +#define PAGES_PER_SUB_SECTION (SECTION_ACTIVE_SIZE / PAGE_SIZE)
> > +#define PAGE_SUB_SECTION_MASK (~(PAGES_PER_SUB_SECTION-1))
> >
> > and change section_active_index to:
> >
> > static inline int section_active_index(unsigned long pfn)
> > {
> >         return (pfn & ~(PAGE_SECTION_MASK)) / SUB_SECTION_ACTIVE_PAGES;

Sorry, here I meant:

return (pfn & ~(PAGE_SECTION_MASK)) / PAGES_PER_SUB_SECTION;

But I think you got the idea :-)

-- 
Oscar Salvador
SUSE L3