Re: [PATCH v4 1/2] huge_mm: add stubs for THP-disabled configs
From: David Hildenbrand (Arm)
Date: Thu Mar 12 2026 - 11:53:30 EST
On 3/10/26 04:11, WANG Rui wrote:
> hugepage_global_enabled() and hugepage_global_always() only exist
> when CONFIG_TRANSPARENT_HUGEPAGE is set. Add inline stubs that
> return false to let code compile when THP is disabled.
>
> Signed-off-by: WANG Rui <r@xxxxxx>
> ---
> include/linux/huge_mm.h | 10 ++++++++++
> 1 file changed, 10 insertions(+)
>
> diff --git a/include/linux/huge_mm.h b/include/linux/huge_mm.h
> index a4d9f964dfde..badeebd4ea98 100644
> --- a/include/linux/huge_mm.h
> +++ b/include/linux/huge_mm.h
> @@ -570,6 +570,16 @@ void map_anon_folio_pmd_nopf(struct folio *folio, pmd_t *pmd,
>
> #else /* CONFIG_TRANSPARENT_HUGEPAGE */
>
> +static inline bool hugepage_global_enabled(void)
> +{
> + return false;
> +}
> +
> +static inline bool hugepage_global_always(void)
> +{
> + return false;
> +}
> +
> static inline bool folio_test_pmd_mappable(struct folio *folio)
> {
> return false;
There are other ways to enable PMD THP. So I don't quite think this is
the right tool for the job.
--
Cheers,
David