Re: [PATCH v9 12/12] mm: stop zeroing memory during allocation in vmemmap

[Michal Hocko]

On Tue 03-10-17 16:26:51, Pasha Tatashin wrote:
> Hi Michal,
> 
> I decided not to merge these two patches, because in addition to sparc
> optimization move, we have this dependancies:

optimizations can and should go on top of the core patch.

> mm: zero reserved and unavailable struct pages
> 
> must be before
> 
> mm: stop zeroing memory during allocation in vmemmap.
> 
> Otherwise, we can end-up with struct pages that are not zeroed properly.

Right and you can deal with it easily. Just introduce the
mm_zero_struct_page earlier along with its user in "stop zeroing ..."

I think that moving the zeroying in one go is more reasonable than
adding it to __init_single_page with misleading numbers and later
dropping the zeroying from the memmap path.
-- 
Michal Hocko
SUSE Labs