From mboxrd@z Thu Jan  1 00:00:00 1970
From: Steve Capper <steve.capper-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>
Subject: Re: [PATCH v10 6/7] ARM: add pmd_[dirty|mkclean] for THP
Date: Mon, 7 Jul 2014 10:22:48 +0100
Message-ID: <20140707092247.GA15168@linaro.org>
References: <1404694438-10272-1-git-send-email-minchan@kernel.org>
 <1404694438-10272-7-git-send-email-minchan@kernel.org>
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To: Minchan Kim <minchan-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
Cc: Andrew Morton <akpm-de/tnXTf+JLsfHDXvbKv3WD2FQJk+8+b@public.gmane.org>, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-mm-Bw31MaZKKs3YtjvyW6yDsg@public.gmane.org, Michael Kerrisk <mtk.manpages-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>, Linux API <linux-api-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>, Hugh Dickins <hughd-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org>, Johannes Weiner <hannes-druUgvl0LCNAfugRpC6u6w@public.gmane.org>, Rik van Riel <riel-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>, KOSAKI Motohiro <kosaki.motohiro-+CUm20s59erQFUHtdCDX3A@public.gmane.org>, Mel Gorman <mgorman-l3A5Bk7waGM@public.gmane.org>, Jason Evans <je-b10kYP2dOMg@public.gmane.org>, Zhang Yanfei <zhangyanfei-BthXqXjhjHXQFUHtdCDX3A@public.gmane.org>, "Kirill A. Shutemov" <kirill-oKw7cIdHH8eLwutG50LtGA@public.gmane.org>, Catalin Marinas <catalin.marinas-5wv7dgnIgG8@public.gmane.org>, Will Deacon <will.deacon-5wv7dgnIgG8@public.gmane.org>, Russell King <linux-lFZ/pmaqli7XmaaqVzeoHQ@public.gmane.org>, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org
List-Id: linux-api@vger.kernel.org

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 <catalin.marinas-5wv7dgnIgG8@public.gmane.org>
> Cc: Will Deacon <will.deacon-5wv7dgnIgG8@public.gmane.org>
> Cc: Steve Capper <steve.capper-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>
> Cc: Russell King <linux-lFZ/pmaqli7XmaaqVzeoHQ@public.gmane.org>
> Cc: linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org
> Signed-off-by: Minchan Kim <minchan-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
> ---
>  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