Re: [External] Re: [PATCH] docs: mm: Fix number of base pages for 1GB HugeTLB

From: Mike Rapoport
Date: Tue Jul 25 2023 - 02:07:58 EST


(adding Jon)

On Mon, Jul 24, 2023 at 03:05:29PM +0100, Usama Arif wrote:
>
>
> On 08/02/2023 09:51, Mike Rapoport wrote:
> > On Tue, Feb 07, 2023 at 11:44:56AM +0000, Usama Arif wrote:
> > > 1GB HugeTLB page consists of 262144 base pages.
> > >
> > > Signed-off-by: Usama Arif <usama.arif@xxxxxxxxxxxxx>
> >
> > Acked-by: Mike Rapoport (IBM) <rppt@xxxxxxxxxx>
> >
> > > ---
> > > Documentation/mm/vmemmap_dedup.rst | 3 ++-
> > > 1 file changed, 2 insertions(+), 1 deletion(-)
> > >
> > > diff --git a/Documentation/mm/vmemmap_dedup.rst b/Documentation/mm/vmemmap_dedup.rst
> > > index a4b12ff906c4..689a6907c70b 100644
> > > --- a/Documentation/mm/vmemmap_dedup.rst
> > > +++ b/Documentation/mm/vmemmap_dedup.rst
> > > @@ -1,3 +1,4 @@
> > > +
> > > .. SPDX-License-Identifier: GPL-2.0
> > > =========================================
> > > @@ -17,7 +18,7 @@ HugeTLB pages consist of multiple base page size pages and is supported by many
> > > architectures. See Documentation/admin-guide/mm/hugetlbpage.rst for more
> > > details. On the x86-64 architecture, HugeTLB pages of size 2MB and 1GB are
> > > currently supported. Since the base page size on x86 is 4KB, a 2MB HugeTLB page
> > > -consists of 512 base pages and a 1GB HugeTLB page consists of 4096 base pages.
> > > +consists of 512 base pages and a 1GB HugeTLB page consists of 262144 base pages.
> > > For each base page, there is a corresponding ``struct page``.
> > > Within the HugeTLB subsystem, only the first 4 ``struct page`` are used to
> > > --
> > > 2.25.1
> > >
> >
>
> Hi,
>
> Was just reading vmemmap_dedup.rst for something and realized that its still
> 4096 pages for 1G, maybe this patch got missed?
>
> Thanks,
> Usama

--
Sincerely yours,
Mike.