Re: [RFC PATCH 3/3] mm: shm: Use new hugetlb size encoding definitions

From: Michal Hocko
Date: Wed Jul 26 2017 - 06:07:25 EST


On Wed 26-07-17 11:53:38, Michal Hocko wrote:
> On Mon 17-07-17 15:28:01, Mike Kravetz wrote:
> > Use the common definitions from hugetlb_encode.h header file for
> > encoding hugetlb size definitions in shmget system call flags. In
> > addition, move these definitions to the from the internal to user
> > (uapi) header file.
>
> s@to the from@from@
>
> >
> > Suggested-by: Matthew Wilcox <willy@xxxxxxxxxxxxx>
> > Signed-off-by: Mike Kravetz <mike.kravetz@xxxxxxxxxx>
>
> with s@HUGETLB_FLAG_ENCODE__16GB@HUGETLB_FLAG_ENCODE_16GB@
>
> Acked-by: Michal Hocko <mhocko@xxxxxxxx>

Btw. man page mentions only 2MB and 1GB, we should document others and
note that each arch might support only subset of them

> > +#define MAP_HUGE_512KB HUGETLB_FLAG_ENCODE_512KB
> > +#define MAP_HUGE_1MB HUGETLB_FLAG_ENCODE_1MB
> > +#define MAP_HUGE_2MB HUGETLB_FLAG_ENCODE_2MB
> > +#define MAP_HUGE_8MB HUGETLB_FLAG_ENCODE_8MB
> > +#define MAP_HUGE_16MB HUGETLB_FLAG_ENCODE_16MB
> > +#define MAP_HUGE_1GB HUGETLB_FLAG_ENCODE_1GB
> > +#define MAP_HUGE_16GB HUGETLB_FLAG_ENCODE__16GB
--
Michal Hocko
SUSE Labs