On Sun, Mar 27, 2016 at 04:33:04PM -0400, George Spelvin wrote: > Could you just mark compound_head __pure? That would tell the compiler > that it's safe to re-use the return value as long as there is no memory > mutation in between. >
Hm. It has some positive impact, but it's not dramatic. For instance, mm/swap.o results: add/remove: 0/0 grow/shrink: 0/2 up/down: 0/-43 (-43) function old new delta __page_cache_release 319 298 -21 release_pages 722 700 -22 mark_page_accessed() problem was not fixed by that. -- Kirill A. Shutemov
