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Message-ID: <463c960e-1d3b-edc0-edbb-d5ecbf7fc3b1@bytedance.com>
Date:   Mon, 24 Jul 2023 15:05:29 +0100
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Subject: Re: [External] Re: [PATCH] docs: mm: Fix number of base pages for 1GB
 HugeTLB
To:     Mike Rapoport <rppt@kernel.org>, songmuchun@bytedance.com,
        linux-mm@kvack.org
Cc:     linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org,
        fam.zheng@bytedance.com, liangma@liangbit.com
References: <20230207114456.2304801-1-usama.arif@bytedance.com>
 <Y+NwkCsDnOBSCqVu@kernel.org>
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From:   Usama Arif <usama.arif@bytedance.com>
In-Reply-To: <Y+NwkCsDnOBSCqVu@kernel.org>
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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