Re: [PATCH] arm64: mm: Drop duplicate check in pmd_trans_huge()

[Dev Jain <dev.jain@arm.com>]

On 08/05/25 9:21 am, Gavin Shan wrote:
> pmd_val(pmd) is inclusive to pmd_present(pmd) since the PMD entry
> value isn't zero when pmd_present() returns true. Just drop the
> duplicate check done by pmd_val(pmd).
> 
> No functional changes intended.
> 
> Signed-off-by: Gavin Shan <gshan@redhat.com>
> ---
> Found this by code inspection
> ---
>   arch/arm64/include/asm/pgtable.h | 3 +--
>   1 file changed, 1 insertion(+), 2 deletions(-)
> 
> diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h
> index d3b538be1500..2599b9b8666f 100644
> --- a/arch/arm64/include/asm/pgtable.h
> +++ b/arch/arm64/include/asm/pgtable.h
> @@ -739,8 +739,7 @@ static inline int pmd_trans_huge(pmd_t pmd)
>   	 * If pmd is present-invalid, pmd_table() won't detect it
>   	 * as a table, so force the valid bit for the comparison.
>   	 */
> -	return pmd_val(pmd) && pmd_present(pmd) &&
> -	       !pmd_table(__pmd(pmd_val(pmd) | PTE_VALID));
> +	return pmd_present(pmd) && !pmd_table(__pmd(pmd_val(pmd) | PTE_VALID));
>   }
>   #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
>   

LGTM

Reviewed-by: Dev Jain <dev.jain@arm.com>