On (04/18/17 09:33), Michal Hocko wrote: [..] > > Another approach is the API does normal thing for non-aligned prefix and > > tail space and fast thing for aligned space. > > Otherwise, it would be happy if the API has WARN_ON non-page SIZE aligned > > address. > > copy_page is a performance sensitive function and I believe that we do > those tricks exactly for this purpose.
a wild thought, use #define copy_page(to,from) memcpy((to), (from), PAGE_SIZE) when DEBUG_SLAB is set? so arch copy_page() (if provided by arch) won't be affected otherwise. -ss