Re: [PATCH v3] mm: mincore: use pte_batch_bint() to batch process large folios

[Baolin Wang]

On 2025/5/9 15:30, Dev Jain wrote:
> On 09/05/25 6:15 am, Baolin Wang wrote:
> > When I tested the mincore() syscall, I observed that it takes longer with
> > 64K mTHP enabled on my Arm64 server. The reason is the 
> > mincore_pte_range()
> > still checks each PTE individually, even when the PTEs are contiguous,
> > which is not efficient.
> >
> > Thus we can use pte_batch_hint() to get the batch number of the present
> > contiguous PTEs, which can improve the performance. I tested the 
> > mincore()
> > syscall with 1G anonymous memory populated with 64K mTHP, and observed an
> > obvious performance improvement:
> >
> > w/o patch        w/ patch        changes
> > 6022us            549us            +91%
> >
> > Moreover, I also tested mincore() with disabling mTHP/THP, and did not
> > see any obvious regression for base pages.
> >
> > Signed-off-by: Baolin Wang <baolin.wang@xxxxxxxxxxxxxxxxx>
>
> Nit: The subject line - s/pte_batch_bint()/pte_batch_hint()

Ah, fat finger. Hope Andrew can help to fix it:)

> Otherwise LGTM
>
> Reviewed-by: Dev Jain <dev.jain@xxxxxxx>

Thanks.