Re: [PATCH v2 00/11] mm: thp: always enable mTHP support

[Luiz Capitulino]

On 2026-04-02 04:25, David Hildenbrand (Arm) wrote:
> On 2/9/26 23:14, Luiz Capitulino wrote:
> > Today, if an architecture implements has_transparent_hugepage() and the CPU
> > lacks support for PMD-sized pages, the THP code disables all THP, including
> > mTHP. In addition, the kernel lacks a well defined API to check for
> > PMD-sized page support. It currently relies on has_transparent_hugepage()
> > and thp_disabled_by_hw(), but they are not well defined and are tied to
> > THP support.
> >
> > This series addresses both issues by introducing a new well defined API
> > to query PMD-sized page support: pgtable_has_pmd_leaves(). Using this
> > new helper, we ensure that mTHP remains enabled even when the
> > architecture or CPU doesn't support PMD-sized pages.
> >
> > Thanks to David Hildenbrand for suggesting this improvement and for
> > providing guidance (all bugs and misconceptions are mine).
> >
> > This applies to v6.19, but I tested it on v6.19-rc8+.
>
> Apologies for the delay Luiz (as told you off-list :) ), I'll try going
> through this soon so we can start queuing this after -rc1.

Oh, wow, thanks for the support!

I intended to get back to this series this week to address Baolin's
comments, but I got busy with other things (which is something I may
bring up on upstream but it's not related to this series at all).