[RFC PATCH 6/6] arm: mm: Add Transparent HugePage support for non-LPAE
From: Steve Capper <hidden>
Date: 2013-12-13 19:05:46
Subsystem:
arm port, the rest · Maintainers:
Russell King, Linus Torvalds
Much of the required code for THP has been implemented in the earlier non-LPAE HugeTLB patch. One more domain bit is used (to store whether or not the THP is splitting). Some THP helper functions are defined; and we have to re-define pmd_page such that it distinguishes between page tables and sections. Signed-off-by: Steve Capper <redacted> --- arch/arm/Kconfig | 2 +- arch/arm/include/asm/pgtable-2level.h | 34 ++++++++++++++++++++++++++++++++++ arch/arm/include/asm/pgtable-3level.h | 1 + arch/arm/include/asm/pgtable.h | 2 -- 4 files changed, 36 insertions(+), 3 deletions(-)
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 2eeee73..f17f5c92 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig@@ -1788,7 +1788,7 @@ config SYS_SUPPORTS_HUGETLBFS config HAVE_ARCH_TRANSPARENT_HUGEPAGE def_bool y - depends on ARM_LPAE + depends on SYS_SUPPORTS_HUGETLBFS config ARCH_WANT_GENERAL_HUGETLB def_bool y
diff --git a/arch/arm/include/asm/pgtable-2level.h b/arch/arm/include/asm/pgtable-2level.h
index 95ed36e..f7c2599 100644
--- a/arch/arm/include/asm/pgtable-2level.h
+++ b/arch/arm/include/asm/pgtable-2level.h@@ -211,6 +211,7 @@ static inline pmd_t *pmd_offset(pud_t *pud, unsigned long addr) */ #define PMD_DSECT_DIRTY (_AT(pmdval_t, 1) << 5) #define PMD_DSECT_AF (_AT(pmdval_t, 1) << 6) +#define PMD_DSECT_SPLITTING (_AT(pmdval_t, 1) << 7) #define PMD_BIT_FUNC(fn,op) \ static inline pmd_t pmd_##fn(pmd_t pmd) { pmd_val(pmd) op; return pmd; }
@@ -234,12 +235,25 @@ extern pgprot_t get_huge_pgprot(pgprot_t newprot); #define pfn_pmd(pfn,prot) __pmd(__pfn_to_phys(pfn) | pgprot_val(prot)); #define mk_pmd(page,prot) pfn_pmd(page_to_pfn(page),get_huge_pgprot(prot)); +#define pmd_mkhuge(pmd) (pmd) + +#ifdef CONFIG_TRANSPARENT_HUGEPAGE +#define pmd_trans_splitting(pmd) (pmd_val(pmd) & PMD_DSECT_SPLITTING) +#define pmd_trans_huge(pmd) (pmd_large(pmd)) +#else +static inline int pmd_trans_huge(pmd_t pmd); +#endif + +#define pmd_mknotpresent(pmd) (__pmd(0)) PMD_BIT_FUNC(mkdirty, |= PMD_DSECT_DIRTY); PMD_BIT_FUNC(mkwrite, |= PMD_SECT_AP_WRITE); PMD_BIT_FUNC(wrprotect, &= ~PMD_SECT_AP_WRITE); PMD_BIT_FUNC(mknexec, |= PMD_SECT_XN); PMD_BIT_FUNC(rmprotnone, |= PMD_TYPE_SECT); +PMD_BIT_FUNC(mkold, &= ~PMD_DSECT_AF); +PMD_BIT_FUNC(mksplitting, |= PMD_DSECT_SPLITTING); +PMD_BIT_FUNC(mkyoung, |= PMD_DSECT_AF); #define pmd_young(pmd) (pmd_val(pmd) & PMD_DSECT_AF) #define pmd_write(pmd) (pmd_val(pmd) & PMD_SECT_AP_WRITE)
@@ -281,6 +295,26 @@ static inline pmd_t pmd_modify(pmd_t pmd, pgprot_t newprot) return pmd; } +static inline int has_transparent_hugepage(void) +{ + return 1; +} + + +static inline struct page *pmd_page(pmd_t pmd) +{ + /* + * for a section, we need to mask off more of the pmd + * before looking up the page as it is a section descriptor. + * + * pmd_page only gets sections from the thp code. + */ + if (pmd_trans_huge(pmd)) + return (phys_to_page(pmd_val(pmd) & HPAGE_MASK)); + + return phys_to_page(pmd_val(pmd) & PHYS_MASK); +} + #endif /* __ASSEMBLY__ */ #endif /* _ASM_PGTABLE_2LEVEL_H */
diff --git a/arch/arm/include/asm/pgtable-3level.h b/arch/arm/include/asm/pgtable-3level.h
index 520a875..4a3a256 100644
--- a/arch/arm/include/asm/pgtable-3level.h
+++ b/arch/arm/include/asm/pgtable-3level.h@@ -215,6 +215,7 @@ static inline pmd_t *pmd_offset(pud_t *pud, unsigned long addr) #define pmd_hugewillfault(pmd) (!pmd_young(pmd) || !pmd_write(pmd)) #define pmd_thp_or_huge(pmd) (pmd_huge(pmd) || pmd_trans_huge(pmd)) +#define pmd_page(pmd) pfn_to_page(__phys_to_pfn(pmd_val(pmd) & PHYS_MASK)) #ifdef CONFIG_TRANSPARENT_HUGEPAGE #define pmd_trans_huge(pmd) (pmd_val(pmd) && !(pmd_val(pmd) & PMD_TABLE_BIT))
diff --git a/arch/arm/include/asm/pgtable.h b/arch/arm/include/asm/pgtable.h
index 9bd4046..361ca7c 100644
--- a/arch/arm/include/asm/pgtable.h
+++ b/arch/arm/include/asm/pgtable.h@@ -189,8 +189,6 @@ static inline pte_t *pmd_page_vaddr(pmd_t pmd) return __va(pmd_val(pmd) & PHYS_MASK & (s32)PAGE_MASK); } -#define pmd_page(pmd) pfn_to_page(__phys_to_pfn(pmd_val(pmd) & PHYS_MASK)) - #ifndef CONFIG_HIGHPTE #define __pte_map(pmd) pmd_page_vaddr(*(pmd)) #define __pte_unmap(pte) do { } while (0)
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1.8.1.4