From 15a25b2ead5f97c5a63c169186e294b41ce03f9a Mon Sep 17 00:00:00 2001 From: "Aneesh Kumar K.V" Date: Wed, 24 Jun 2015 16:57:39 -0700 Subject: mm/thp: split out pmd collapse flush into separate functions Architectures like ppc64 [1] need to do special things while clearing pmd before a collapse. For them this operation is largely different from a normal hugepage pte clear. Hence add a separate function to clear pmd before collapse. After this patch pmdp_* functions operate only on hugepage pte, and not on regular pmd_t values pointing to page table. [1] ppc64 needs to invalidate all the normal page pte mappings we already have inserted in the hardware hash page table. But before doing that we need to make sure there are no parallel hash page table insert going on. So we need to do a kick_all_cpus_sync() before flushing the older hash table entries. By moving this to a separate function we capture these details and mention how it is different from a hugepage pte clear. This patch is a cleanup and only does code movement for clarity. There should not be any change in functionality. Signed-off-by: Aneesh Kumar K.V Acked-by: Kirill A. Shutemov Cc: Benjamin Herrenschmidt Cc: Paul Mackerras Cc: Michael Ellerman Cc: Andrea Arcangeli Cc: Martin Schwidefsky Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/asm-generic/pgtable.h | 21 +++++++++++++++++++++ 1 file changed, 21 insertions(+) (limited to 'include/asm-generic') diff --git a/include/asm-generic/pgtable.h b/include/asm-generic/pgtable.h index bd910ceaccfa..d2c2171d1c32 100644 --- a/include/asm-generic/pgtable.h +++ b/include/asm-generic/pgtable.h @@ -189,6 +189,27 @@ extern void pmdp_splitting_flush(struct vm_area_struct *vma, unsigned long address, pmd_t *pmdp); #endif +#ifndef pmdp_collapse_flush +#ifdef CONFIG_TRANSPARENT_HUGEPAGE +static inline pmd_t pmdp_collapse_flush(struct vm_area_struct *vma, + unsigned long address, + pmd_t *pmdp) +{ + return pmdp_clear_flush(vma, address, pmdp); +} +#define pmdp_collapse_flush pmdp_collapse_flush +#else +static inline pmd_t pmdp_collapse_flush(struct vm_area_struct *vma, + unsigned long address, + pmd_t *pmdp) +{ + BUILD_BUG(); + return *pmdp; +} +#define pmdp_collapse_flush pmdp_collapse_flush +#endif /* CONFIG_TRANSPARENT_HUGEPAGE */ +#endif + #ifndef __HAVE_ARCH_PGTABLE_DEPOSIT extern void pgtable_trans_huge_deposit(struct mm_struct *mm, pmd_t *pmdp, pgtable_t pgtable); -- cgit v1.2.3 From f28b6ff8c3d48af21354ef30164c8ccea69d5928 Mon Sep 17 00:00:00 2001 From: "Aneesh Kumar K.V" Date: Wed, 24 Jun 2015 16:57:42 -0700 Subject: powerpc/mm: use generic version of pmdp_clear_flush() Also move the pmd_trans_huge check to generic code. Signed-off-by: Aneesh Kumar K.V Acked-by: Kirill A. Shutemov Cc: Benjamin Herrenschmidt Cc: Paul Mackerras Cc: Michael Ellerman Cc: Andrea Arcangeli Cc: Martin Schwidefsky Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/asm-generic/pgtable.h | 9 ++------- 1 file changed, 2 insertions(+), 7 deletions(-) (limited to 'include/asm-generic') diff --git a/include/asm-generic/pgtable.h b/include/asm-generic/pgtable.h index d2c2171d1c32..f1108a72a672 100644 --- a/include/asm-generic/pgtable.h +++ b/include/asm-generic/pgtable.h @@ -191,13 +191,8 @@ extern void pmdp_splitting_flush(struct vm_area_struct *vma, #ifndef pmdp_collapse_flush #ifdef CONFIG_TRANSPARENT_HUGEPAGE -static inline pmd_t pmdp_collapse_flush(struct vm_area_struct *vma, - unsigned long address, - pmd_t *pmdp) -{ - return pmdp_clear_flush(vma, address, pmdp); -} -#define pmdp_collapse_flush pmdp_collapse_flush +extern pmd_t pmdp_collapse_flush(struct vm_area_struct *vma, + unsigned long address, pmd_t *pmdp); #else static inline pmd_t pmdp_collapse_flush(struct vm_area_struct *vma, unsigned long address, -- cgit v1.2.3 From 8809aa2d28d74111ff2f1928edaa4e9845c97a7d Mon Sep 17 00:00:00 2001 From: "Aneesh Kumar K.V" Date: Wed, 24 Jun 2015 16:57:44 -0700 Subject: mm: clarify that the function operates on hugepage pte We have confusing functions to clear pmd, pmd_clear_* and pmd_clear. Add _huge_ to pmdp_clear functions so that we are clear that they operate on hugepage pte. We don't bother about other functions like pmdp_set_wrprotect, pmdp_clear_flush_young, because they operate on PTE bits and hence indicate they are operating on hugepage ptes Signed-off-by: Aneesh Kumar K.V Acked-by: Kirill A. Shutemov Cc: Benjamin Herrenschmidt Cc: Paul Mackerras Cc: Michael Ellerman Cc: Andrea Arcangeli Cc: Martin Schwidefsky Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/asm-generic/pgtable.h | 18 +++++++++--------- 1 file changed, 9 insertions(+), 9 deletions(-) (limited to 'include/asm-generic') diff --git a/include/asm-generic/pgtable.h b/include/asm-generic/pgtable.h index f1108a72a672..29c57b2cb344 100644 --- a/include/asm-generic/pgtable.h +++ b/include/asm-generic/pgtable.h @@ -96,11 +96,11 @@ static inline pte_t ptep_get_and_clear(struct mm_struct *mm, } #endif -#ifndef __HAVE_ARCH_PMDP_GET_AND_CLEAR +#ifndef __HAVE_ARCH_PMDP_HUGE_GET_AND_CLEAR #ifdef CONFIG_TRANSPARENT_HUGEPAGE -static inline pmd_t pmdp_get_and_clear(struct mm_struct *mm, - unsigned long address, - pmd_t *pmdp) +static inline pmd_t pmdp_huge_get_and_clear(struct mm_struct *mm, + unsigned long address, + pmd_t *pmdp) { pmd_t pmd = *pmdp; pmd_clear(pmdp); @@ -109,13 +109,13 @@ static inline pmd_t pmdp_get_and_clear(struct mm_struct *mm, #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ #endif -#ifndef __HAVE_ARCH_PMDP_GET_AND_CLEAR_FULL +#ifndef __HAVE_ARCH_PMDP_HUGE_GET_AND_CLEAR_FULL #ifdef CONFIG_TRANSPARENT_HUGEPAGE -static inline pmd_t pmdp_get_and_clear_full(struct mm_struct *mm, +static inline pmd_t pmdp_huge_get_and_clear_full(struct mm_struct *mm, unsigned long address, pmd_t *pmdp, int full) { - return pmdp_get_and_clear(mm, address, pmdp); + return pmdp_huge_get_and_clear(mm, address, pmdp); } #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ #endif @@ -152,8 +152,8 @@ extern pte_t ptep_clear_flush(struct vm_area_struct *vma, pte_t *ptep); #endif -#ifndef __HAVE_ARCH_PMDP_CLEAR_FLUSH -extern pmd_t pmdp_clear_flush(struct vm_area_struct *vma, +#ifndef __HAVE_ARCH_PMDP_HUGE_CLEAR_FLUSH +extern pmd_t pmdp_huge_clear_flush(struct vm_area_struct *vma, unsigned long address, pmd_t *pmdp); #endif -- cgit v1.2.3