Re: [PATCH V2] mm: Introduce GFP_PGTABLE

From: Anshuman Khandual
Date: Wed Jan 16 2019 - 07:39:50 EST




On 01/16/2019 12:40 PM, Christophe Leroy wrote:
>
>
> Le 16/01/2019 Ã 07:21, Anshuman Khandual a ÃcritÂ:
>> All architectures have been defining their own PGALLOC_GFP as (GFP_KERNEL |
>> __GFP_ZERO) and using it for allocating page table pages. This causes some
>> code duplication which can be easily avoided. GFP_KERNEL allocated and
>> cleared out pages (__GFP_ZERO) are required for page tables on any given
>> architecture. This creates a new generic GFP flag flag which can be used
>> for any page table page allocation. Does not cause any functional change.
>>
>> GFP_PGTABLE is being added into include/asm-generic/pgtable.h which is the
>> generic page tabe header just to prevent it's potential misuse as a general
>> allocation flag if included in include/linux/gfp.h.
>>
>> Signed-off-by: Anshuman Khandual <anshuman.khandual@xxxxxxx>
>> ---
>> Build tested on arm, arm64, powerpc, powerpc64le and x86.
>> Boot tested on arm64 and x86.
>>
>> Changes in V2:
>>
>> - Moved GFP_PGTABLE into include/asm-generic/pgtable.h
>> - On X86 added __GFP_ACCOUNT into GFP_PGTABLE at various places
>> - Replaced possible flags on riscv and nds32 with GFP_PGTABLE
>
> Could also replace the flags in arch/powerpc/include/asm/nohash/64/pgalloc.h with GFP_PGTABLE in pte_alloc_one_kernel() and pte_alloc_one()

Sure will do.