On Mon, Jun 29, 2020 at 04:19:53PM +0100, Matthew Wilcox (Oracle) wrote: > This removes a few instructions from functions which need to know how many > pages are in a compound page. The storage used is either page->mapping > on 64-bit or page->index on 32-bit. Both of these are fine to overlay > on tail pages. I'm not a fan of redundant data in struct page, even if it's less busy tail page. We tend to find more use of the space over time. Any numbers on what it gives for typical kernel? Does it really worth it? -- Kirill A. Shutemov
