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Subject: Re: [PATCH V4 02/18] mm: Some arch may want to use HPAGE_PMD related
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From: Balbir Singh <bsingharora@gmail.com>
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Date: Thu, 25 Feb 2016 16:06:25 +1100
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On 23/02/16 15:48, Aneesh Kumar K.V wrote:
> From: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
In the changelog, strip from here <--
> With next generation power processor, we are having a new mmu model
> [1] that require us to maintain a different linux page table format.
>
> Inorder to support both current and future ppc64 systems with a single
> kernel we need to make sure kernel can select between different page
> table format at runtime.

---> till here

>  With the new MMU (radix MMU) added, we will
> have two different pmd hugepage size 16MB for hash model and 2MB for
> Radix model. Hence make HPAGE_PMD related values as a variable.
>
> Actual conversion of HPAGE_PMD to a variable for ppc64 happens in a
> followup patch.
>
> [1] http://ibm.biz/power-isa3 (Needs registration).
>
> Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>

Balbir Singh.