[PATCH v13 6/8] arm: add pmd_[dirty|mkclean] for THP

[PATCH v13 6/8] arm: add pmd_[dirty|mkclean] for THP

[Minchan Kim]

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@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Steve Capper <steve.capper@linaro.org>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: linux-arm-kernel at lists.infradead.org
Signed-off-by: Minchan Kim <minchan@kernel.org>
---
 arch/arm/include/asm/pgtable-3level.h | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/arch/arm/include/asm/pgtable-3level.h b/arch/arm/include/asm/pgtable-3level.h
index 85c60adc8b60..830f84f2d277 100644
--- a/arch/arm/include/asm/pgtable-3level.h
+++ b/arch/arm/include/asm/pgtable-3level.h
@@ -220,6 +220,8 @@ static inline pmd_t *pmd_offset(pud_t *pud, unsigned long addr)
 #define pmd_trans_splitting(pmd) (pmd_val(pmd) & PMD_SECT_SPLITTING)
 #endif
 
+#define pmd_dirty(pmd)		(pmd_val(pmd) & PMD_SECT_DIRTY)
+
 #define PMD_BIT_FUNC(fn,op) \
 static inline pmd_t pmd_##fn(pmd_t pmd) { pmd_val(pmd) op; return pmd; }
 
@@ -228,6 +230,7 @@ PMD_BIT_FUNC(mkold,	&= ~PMD_SECT_AF);
 PMD_BIT_FUNC(mksplitting, |= PMD_SECT_SPLITTING);
 PMD_BIT_FUNC(mkwrite,   &= ~PMD_SECT_RDONLY);
 PMD_BIT_FUNC(mkdirty,   |= PMD_SECT_DIRTY);
+PMD_BIT_FUNC(mkclean,   &= ~PMD_SECT_DIRTY);
 PMD_BIT_FUNC(mkyoung,   |= PMD_SECT_AF);
 
 #define pmd_mkhuge(pmd)		(__pmd(pmd_val(pmd) & ~PMD_TABLE_BIT))
-- 
2.0.0

[PATCH v13 7/8] arm64: add pmd_[dirty|mkclean] for THP

[Minchan Kim]

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@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Steve Capper <steve.capper@linaro.org>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: linux-arm-kernel at lists.infradead.org
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Minchan Kim <minchan@kernel.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 e0ccceb317d9..41dfe3c7260c 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

[PATCH v13 6/8] arm: add pmd_[dirty|mkclean] for THP

[Will Deacon]

On Fri, Jul 18, 2014 at 07:53:04AM +0100, 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@arm.com>
> Cc: Will Deacon <will.deacon@arm.com>
> Cc: Steve Capper <steve.capper@linaro.org>
> Cc: Russell King <linux@arm.linux.org.uk>
> Cc: linux-arm-kernel at lists.infradead.org
> Signed-off-by: Minchan Kim <minchan@kernel.org>
> ---
>  arch/arm/include/asm/pgtable-3level.h | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/arch/arm/include/asm/pgtable-3level.h b/arch/arm/include/asm/pgtable-3level.h
> index 85c60adc8b60..830f84f2d277 100644
> --- a/arch/arm/include/asm/pgtable-3level.h
> +++ b/arch/arm/include/asm/pgtable-3level.h
> @@ -220,6 +220,8 @@ static inline pmd_t *pmd_offset(pud_t *pud, unsigned long addr)
>  #define pmd_trans_splitting(pmd) (pmd_val(pmd) & PMD_SECT_SPLITTING)
>  #endif
>  
> +#define pmd_dirty(pmd)		(pmd_val(pmd) & PMD_SECT_DIRTY)
> +
>  #define PMD_BIT_FUNC(fn,op) \
>  static inline pmd_t pmd_##fn(pmd_t pmd) { pmd_val(pmd) op; return pmd; }
>  
> @@ -228,6 +230,7 @@ PMD_BIT_FUNC(mkold,	&= ~PMD_SECT_AF);
>  PMD_BIT_FUNC(mksplitting, |= PMD_SECT_SPLITTING);
>  PMD_BIT_FUNC(mkwrite,   &= ~PMD_SECT_RDONLY);
>  PMD_BIT_FUNC(mkdirty,   |= PMD_SECT_DIRTY);
> +PMD_BIT_FUNC(mkclean,   &= ~PMD_SECT_DIRTY);
>  PMD_BIT_FUNC(mkyoung,   |= PMD_SECT_AF);
>  
>  #define pmd_mkhuge(pmd)		(__pmd(pmd_val(pmd) & ~PMD_TABLE_BIT))

Looks fine to me, but again, it would be great if Steve can take a look too.

Will

[PATCH v13 6/8] arm: add pmd_[dirty|mkclean] for THP

[Steve Capper]

On Fri, Jul 18, 2014 at 03:53:04PM +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@arm.com>
> Cc: Will Deacon <will.deacon@arm.com>
> Cc: Steve Capper <steve.capper@linaro.org>
> Cc: Russell King <linux@arm.linux.org.uk>
> Cc: linux-arm-kernel at lists.infradead.org
> Signed-off-by: Minchan Kim <minchan@kernel.org>

This patch looks good to me:
Acked-by: Steve Capper <steve.capper@linaro.org>

There is another patch that introduces a helper function to test for
pmd bits, please see below.

> ---
>  arch/arm/include/asm/pgtable-3level.h | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/arch/arm/include/asm/pgtable-3level.h b/arch/arm/include/asm/pgtable-3level.h
> index 85c60adc8b60..830f84f2d277 100644
> --- a/arch/arm/include/asm/pgtable-3level.h
> +++ b/arch/arm/include/asm/pgtable-3level.h
> @@ -220,6 +220,8 @@ static inline pmd_t *pmd_offset(pud_t *pud, unsigned long addr)
>  #define pmd_trans_splitting(pmd) (pmd_val(pmd) & PMD_SECT_SPLITTING)
>  #endif
>  
> +#define pmd_dirty(pmd)		(pmd_val(pmd) & PMD_SECT_DIRTY)

Russell,
Should this be folded into my {pte|pmd}_isset patch?
http://lists.infradead.org/pipermail/linux-arm-kernel/2014-July/268979.html

Cheers,
-- 
Steve


> +
>  #define PMD_BIT_FUNC(fn,op) \
>  static inline pmd_t pmd_##fn(pmd_t pmd) { pmd_val(pmd) op; return pmd; }
>  
> @@ -228,6 +230,7 @@ PMD_BIT_FUNC(mkold,	&= ~PMD_SECT_AF);
>  PMD_BIT_FUNC(mksplitting, |= PMD_SECT_SPLITTING);
>  PMD_BIT_FUNC(mkwrite,   &= ~PMD_SECT_RDONLY);
>  PMD_BIT_FUNC(mkdirty,   |= PMD_SECT_DIRTY);
> +PMD_BIT_FUNC(mkclean,   &= ~PMD_SECT_DIRTY);
>  PMD_BIT_FUNC(mkyoung,   |= PMD_SECT_AF);
>  
>  #define pmd_mkhuge(pmd)		(__pmd(pmd_val(pmd) & ~PMD_TABLE_BIT))
> -- 
> 2.0.0
> 

[PATCH v13 7/8] arm64: add pmd_[dirty|mkclean] for THP

[Steve Capper]

On Fri, Jul 18, 2014 at 03:53:05PM +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@arm.com>
> Cc: Will Deacon <will.deacon@arm.com>
> Cc: Steve Capper <steve.capper@linaro.org>
> Cc: Russell King <linux@arm.linux.org.uk>
> Cc: linux-arm-kernel at lists.infradead.org
> Acked-by: Catalin Marinas <catalin.marinas@arm.com>
> Signed-off-by: Minchan Kim <minchan@kernel.org>

Acked-by: Steve Capper <steve.capper@linaro.org>