docs: mm: Fix number of base pages for 1GB HugeTLB

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

Posted by Usama Arif 2 years, 7 months ago

1GB HugeTLB page consists of 262144 base pages.

Signed-off-by: Usama Arif <usama.arif@bytedance.com>
---
 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

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

Posted by David Hildenbrand 2 years, 1 month ago

On 07.02.23 12:44, Usama Arif wrote:
> 1GB HugeTLB page consists of 262144 base pages.
> 
> Signed-off-by: Usama Arif <usama.arif@bytedance.com>
> ---
>   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

Reviewed-by: David Hildenbrand <david@redhat.com>

-- 
Cheers,

David / dhildenb

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

Posted by Mike Rapoport 2 years, 7 months ago

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@bytedance.com>

Acked-by: Mike Rapoport (IBM) <rppt@kernel.org>

> ---
>  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
> 

-- 
Sincerely yours,
Mike.

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

Posted by Usama Arif 2 years, 1 month ago


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@bytedance.com>
> 
> Acked-by: Mike Rapoport (IBM) <rppt@kernel.org>
> 
>> ---
>>   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

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

Posted by Mike Rapoport 2 years, 1 month ago

(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@bytedance.com>
> > 
> > Acked-by: Mike Rapoport (IBM) <rppt@kernel.org>
> > 
> > > ---
> > >   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.

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

Posted by Jonathan Corbet 2 years, 1 month ago

Mike Rapoport <rppt@kernel.org> writes:

> (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@bytedance.com>
>> > 
>> > Acked-by: Mike Rapoport (IBM) <rppt@kernel.org>
>> > 
>> > > ---
>> > >   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?

Dug out of the archives and applied, thanks.

jon

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

Posted by Muchun Song 2 years, 7 months ago

On Tue, Feb 7, 2023 at 7:45 PM Usama Arif <usama.arif@bytedance.com> wrote:
>
> 1GB HugeTLB page consists of 262144 base pages.
>
> Signed-off-by: Usama Arif <usama.arif@bytedance.com>

Thanks for your fix.

Acked-by: Muchun Song <songmuchun@bytedance.com>