Re: [PATCH 1/3] selftests/mm: make file-backed THP split work by setting force option

[Zi Yan]

On Wed Jan 22, 2025 at 10:27 AM EST, David Hildenbrand wrote:
> On 22.01.25 16:16, Zi Yan wrote:
>> On Wed Jan 22, 2025 at 9:26 AM EST, David Hildenbrand wrote:
>>> On 22.01.25 13:40, Zi Yan wrote:
>>>> Commit acd7ccb284b8 ("mm: shmem: add large folio support for tmpfs")
>>>> changes huge=always to allocate THP/mTHP based on write size and
>>>> split_huge_page_test does not write PMD size data, so file-back THP is not
>>>> created during the test.
>>>
>>> Just curious, why can't we write PMD size data instead, to avoid messing
>>> with the "force" option?
>> 
>> It also works. I used "force", because I notice that it is intended for
>> testing. Using it might be more future proof, in case huge=always changes
>> its semantics again in the future.
>
> I recall discussing with Hugh in an upstream call that "force" is a 
> relict from older times, so naturally I would have just adjusted the 
> test case to trigger the PMD scenario. No strong opinion, though, was 
> just wondering.

Got it. Let me change it and resend. Thank you for the feedback.



-- 
Best Regards,
Yan, Zi