Re: [PATCH] mm: Improve dump_page() for compound pages

["Kirill A. Shutemov" <kirill@xxxxxxxxxxxxx>]

On Mon, Feb 10, 2020 at 01:33:22PM -0800, John Hubbard wrote:
> > PageSlab() can be called for the head page.
> 
> 
> It's not clear to me whether it's safer to use the...user-provided page, or the
> head page, for checking PageSlab()--it's probably set on both head and non-head
> pages, right?

PageSlab() will call compound_head() inside.

> I guess you're saying it should be like this:
> 
> 	mapcount = PageSlab(head) ? 0 : page_mapcount(page);
> 
> ...yes?

Yes.

-- 
 Kirill A. Shutemov