On Fri, May 22, 2020 at 08:15:17PM +0300, Kirill A. Shutemov wrote: > On Fri, May 15, 2020 at 06:16:26AM -0700, Matthew Wilcox wrote: > > +#define offset_in_thp(page, p) ((unsigned long)(p) & (thp_size(page) - > > 1)) > > Looks like thp_mask() would be handy here.
It's not the only place we could use a thp_mask(), but PAGE_MASK is the inverse of what I think it should be: include/asm-generic/page.h:#define PAGE_MASK (~(PAGE_SIZE-1)) ie addr & PAGE_MASK returns the address aligned to page size, not the offset within the page. Given this ambiguity, I'm inclined to leave it as (thp_size(page) - 1), as it's clear which bits we're masking off.
