Subject: [PATCH v10 6/7] ARM: add pmd_[dirty|mkclean] for THP

From: [email-masked] (Steve Capper)
Date: Mon, 7 Jul 2014 10:22:48 +0100

On Mon, Jul 07, 2014 at 09:53:57AM +0900, Minchan Kim wrote:
> MADV_FREE needs pmd_dirty and pmd_mkclean for detecting recent
> overwrite of the contents since MADV_FREE syscall is called for
> THP page.
> 
> This patch adds pmd_dirty and pmd_mkclean for THP page MADV_FREE
> support.
> 
> Cc: Catalin Marinas <[email-masked]>
> Cc: Will Deacon <[email-masked]>
> Cc: Steve Capper <[email-masked]>
> Cc: Russell King <[email-masked]>
> Cc: linux-arm-kernel at lists.infradead.org
> Signed-off-by: Minchan Kim <[email-masked]>
> ---
>  arch/arm64/include/asm/pgtable.h | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h
> index 579702086488..f3ec01cef04f 100644
> --- a/arch/arm64/include/asm/pgtable.h
> +++ b/arch/arm64/include/asm/pgtable.h
> @@ -240,10 +240,12 @@ static inline pmd_t pte_pmd(pte_t pte)
>  #endif
>  
>  #define pmd_young(pmd)		pte_young(pmd_pte(pmd))
> +#define pmd_dirty(pmd)		pte_dirty(pmd_pte(pmd))
>  #define pmd_wrprotect(pmd)	pte_pmd(pte_wrprotect(pmd_pte(pmd)))
>  #define pmd_mksplitting(pmd)	pte_pmd(pte_mkspecial(pmd_pte(pmd)))
>  #define pmd_mkold(pmd)		pte_pmd(pte_mkold(pmd_pte(pmd)))
>  #define pmd_mkwrite(pmd)	pte_pmd(pte_mkwrite(pmd_pte(pmd)))
> +#define pmd_mkclean(pmd)	pte_pmd(pte_mkclean(pmd_pte(pmd)))
>  #define pmd_mkdirty(pmd)	pte_pmd(pte_mkdirty(pmd_pte(pmd)))
>  #define pmd_mkyoung(pmd)	pte_pmd(pte_mkyoung(pmd_pte(pmd)))
>  #define pmd_mknotpresent(pmd)	(__pmd(pmd_val(pmd) & ~PMD_TYPE_MASK))
> -- 
> 2.0.0
>

Hi Minchan,

This looks good to me too.
As Will said this applies to arm64, we will also need a version for:
arch/arm/include/asm/pgtable-3level.h.

Is there a testcase we can run to check that this patch set is working
well for arm/arm64?

Cheers,
-- 
Steve