On Thu, Mar 12, 2020 at 12:03:58AM +0100, Vlastimil Babka wrote: > On 3/11/20 11:58 PM, Roman Gushchin wrote: > >> > >> I agree it should be in the noise. But please do put it behind CONFIG_CMA > >> #ifdef. My x86_64 desktop distro kernel doesn't have CONFIG_CMA. Even if this is > >> effectively no-op with __rmqueue_cma_fallback() returning NULL immediately, I > >> think the compiler cannot eliminate the two zone_page_state()'s which are > >> atomic_long_read(), even if it's just ultimately READ_ONCE() here, that's a > >> volatile cast which means elimination not possible AFAIK? Other architectures > >> might be even more involved. > > > > I agree. > > > > Andrew, > > can you, please, squash the following diff into the patch? > > Thanks, > > then please add to the result > > Acked-by: Vlastimil Babka <vbabka@xxxxxxx> Thank you!
