Re: [PATCH RFC v3 01/35] mm: page_alloc: Add gfp_flags parameter to arch_alloc_page()

Anshuman Khandual
2024-01-30T04:26:43Z

On 1/29/24 17:11, Alexandru Elisei wrote:
> Hi,
>
> On Mon, Jan 29, 2024 at 11:18:59AM +0530, Anshuman Khandual wrote:
>> On 1/25/24 22:12, Alexandru Elisei wrote:
>>> Extend the usefulness of arch_alloc_page() by adding the gfp_flags
>>> parameter.
>> Although the change here is harmless in itself, it will definitely benefit
>> from some additional context explaining the rationale, taking into account
>> why-how arch_alloc_page() got added particularly for s390 platform and how
>> it's going to be used in the present proposal.
> arm64 will use it to reserve tag storage if the caller requested a tagged
> page. Right now that means that __GFP_ZEROTAGS is set in the gfp mask, but
> I'll rename it to __GFP_TAGGED in patch #18 ("arm64: mte: Rename
> __GFP_ZEROTAGS to __GFP_TAGGED") [1].
>
> [1] https://lore.kernel.org/lkml/20240125164256.4147-19-alexandru.elisei@arm.com/

Makes sense, but please do update the commit message explaining how
new gfp mask argument will be used to detect tagged page allocation
requests, further requiring tag storage allocation.