From: Kirill A. Shutemov Date: Sat, 16 Jan 2016 00:53:17 +0000 (-0800) Subject: mips, thp: remove infrastructure for handling splitting PMDs X-Git-Tag: v4.9.8~2863^2~109 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=b27873702b0604dc4000811e6aa43e18457013de;p=platform%2Fkernel%2Flinux-rpi3.git mips, thp: remove infrastructure for handling splitting PMDs With new refcounting we don't need to mark PMDs splitting. Let's drop code to handle this. pmdp_splitting_flush() is not needed too: on splitting PMD we will do pmdp_clear_flush() + set_pte_at(). pmdp_clear_flush() will do IPI as needed for fast_gup. Signed-off-by: Kirill A. Shutemov Cc: Sasha Levin Cc: Aneesh Kumar K.V Cc: Jerome Marchand Cc: Vlastimil Babka Cc: Andrea Arcangeli Cc: Hugh Dickins Cc: Dave Hansen Cc: Mel Gorman Cc: Rik van Riel Cc: Naoya Horiguchi Cc: Steve Capper Cc: Johannes Weiner Cc: Michal Hocko Cc: Christoph Lameter Cc: David Rientjes Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- diff --git a/arch/mips/include/asm/pgtable-bits.h b/arch/mips/include/asm/pgtable-bits.h index ff7ad91..97b3138 100644 --- a/arch/mips/include/asm/pgtable-bits.h +++ b/arch/mips/include/asm/pgtable-bits.h @@ -131,14 +131,12 @@ /* Huge TLB page */ #define _PAGE_HUGE_SHIFT (_PAGE_MODIFIED_SHIFT + 1) #define _PAGE_HUGE (1 << _PAGE_HUGE_SHIFT) -#define _PAGE_SPLITTING_SHIFT (_PAGE_HUGE_SHIFT + 1) -#define _PAGE_SPLITTING (1 << _PAGE_SPLITTING_SHIFT) #endif /* CONFIG_64BIT && CONFIG_MIPS_HUGE_TLB_SUPPORT */ #if defined(CONFIG_CPU_MIPSR2) || defined(CONFIG_CPU_MIPSR6) /* XI - page cannot be executed */ -#ifdef _PAGE_SPLITTING_SHIFT -#define _PAGE_NO_EXEC_SHIFT (_PAGE_SPLITTING_SHIFT + 1) +#ifdef _PAGE_HUGE_SHIFT +#define _PAGE_NO_EXEC_SHIFT (_PAGE_HUGE_SHIFT + 1) #else #define _PAGE_NO_EXEC_SHIFT (_PAGE_MODIFIED_SHIFT + 1) #endif @@ -153,8 +151,8 @@ #if defined(_PAGE_NO_READ_SHIFT) #define _PAGE_GLOBAL_SHIFT (_PAGE_NO_READ_SHIFT + 1) -#elif defined(_PAGE_SPLITTING_SHIFT) -#define _PAGE_GLOBAL_SHIFT (_PAGE_SPLITTING_SHIFT + 1) +#elif defined(_PAGE_HUGE_SHIFT) +#define _PAGE_GLOBAL_SHIFT (_PAGE_HUGE_SHIFT + 1) #else #define _PAGE_GLOBAL_SHIFT (_PAGE_MODIFIED_SHIFT + 1) #endif diff --git a/arch/mips/include/asm/pgtable.h b/arch/mips/include/asm/pgtable.h index 8957f15..6995b4a 100644 --- a/arch/mips/include/asm/pgtable.h +++ b/arch/mips/include/asm/pgtable.h @@ -482,27 +482,9 @@ static inline pmd_t pmd_mkhuge(pmd_t pmd) return pmd; } -static inline int pmd_trans_splitting(pmd_t pmd) -{ - return !!(pmd_val(pmd) & _PAGE_SPLITTING); -} - -static inline pmd_t pmd_mksplitting(pmd_t pmd) -{ - pmd_val(pmd) |= _PAGE_SPLITTING; - - return pmd; -} - extern void set_pmd_at(struct mm_struct *mm, unsigned long addr, pmd_t *pmdp, pmd_t pmd); -#define __HAVE_ARCH_PMDP_SPLITTING_FLUSH -/* Extern to avoid header file madness */ -extern void pmdp_splitting_flush(struct vm_area_struct *vma, - unsigned long address, - pmd_t *pmdp); - #define __HAVE_ARCH_PMD_WRITE static inline int pmd_write(pmd_t pmd) { diff --git a/arch/mips/mm/gup.c b/arch/mips/mm/gup.c index 36a3511..1afd87c 100644 --- a/arch/mips/mm/gup.c +++ b/arch/mips/mm/gup.c @@ -107,18 +107,7 @@ static int gup_pmd_range(pud_t pud, unsigned long addr, unsigned long end, pmd_t pmd = *pmdp; next = pmd_addr_end(addr, end); - /* - * The pmd_trans_splitting() check below explains why - * pmdp_splitting_flush has to flush the tlb, to stop - * this gup-fast code from running while we set the - * splitting bit in the pmd. Returning zero will take - * the slow path that will call wait_split_huge_page() - * if the pmd is still in splitting state. gup-fast - * can't because it has irq disabled and - * wait_split_huge_page() would never return as the - * tlb flush IPI wouldn't run. - */ - if (pmd_none(pmd) || pmd_trans_splitting(pmd)) + if (pmd_none(pmd)) return 0; if (unlikely(pmd_huge(pmd))) { if (!gup_huge_pmd(pmd, addr, next, write, pages,nr)) diff --git a/arch/mips/mm/pgtable-64.c b/arch/mips/mm/pgtable-64.c index e8adc00..ce4473e 100644 --- a/arch/mips/mm/pgtable-64.c +++ b/arch/mips/mm/pgtable-64.c @@ -62,20 +62,6 @@ void pmd_init(unsigned long addr, unsigned long pagetable) } #endif -#ifdef CONFIG_TRANSPARENT_HUGEPAGE - -void pmdp_splitting_flush(struct vm_area_struct *vma, - unsigned long address, - pmd_t *pmdp) -{ - if (!pmd_trans_splitting(*pmdp)) { - pmd_t pmd = pmd_mksplitting(*pmdp); - set_pmd_at(vma->vm_mm, address, pmdp, pmd); - } -} - -#endif - pmd_t mk_pmd(struct page *page, pgprot_t prot) { pmd_t pmd; diff --git a/arch/mips/mm/tlbex.c b/arch/mips/mm/tlbex.c index 32e0be2..482192c 100644 --- a/arch/mips/mm/tlbex.c +++ b/arch/mips/mm/tlbex.c @@ -240,7 +240,6 @@ static void output_pgtable_bits_defines(void) pr_define("_PAGE_MODIFIED_SHIFT %d\n", _PAGE_MODIFIED_SHIFT); #ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT pr_define("_PAGE_HUGE_SHIFT %d\n", _PAGE_HUGE_SHIFT); - pr_define("_PAGE_SPLITTING_SHIFT %d\n", _PAGE_SPLITTING_SHIFT); #endif #ifdef CONFIG_CPU_MIPSR2 if (cpu_has_rixi) {