From e180377f1ae48b3cbc559c9875d9b038f7f000c6 Mon Sep 17 00:00:00 2001 From: "Kirill A. Shutemov" Date: Wed, 12 Dec 2012 13:50:59 -0800 Subject: [PATCH] thp: change split_huge_page_pmd() interface Pass vma instead of mm and add address parameter. In most cases we already have vma on the stack. We provides split_huge_page_pmd_mm() for few cases when we have mm, but not vma. This change is preparation to huge zero pmd splitting implementation. Signed-off-by: Kirill A. Shutemov Cc: Andrea Arcangeli Cc: Andi Kleen Cc: "H. Peter Anvin" Cc: Mel Gorman Cc: David Rientjes Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- Documentation/vm/transhuge.txt | 4 ++-- arch/x86/kernel/vm86_32.c | 2 +- fs/proc/task_mmu.c | 2 +- include/linux/huge_mm.h | 14 ++++++++++---- mm/huge_memory.c | 19 +++++++++++++++++-- mm/memory.c | 4 ++-- mm/mempolicy.c | 2 +- mm/mprotect.c | 2 +- mm/mremap.c | 2 +- mm/pagewalk.c | 2 +- 10 files changed, 37 insertions(+), 16 deletions(-) diff --git a/Documentation/vm/transhuge.txt b/Documentation/vm/transhuge.txt index f734bb2a78d..8f5b41db314 100644 --- a/Documentation/vm/transhuge.txt +++ b/Documentation/vm/transhuge.txt @@ -276,7 +276,7 @@ unaffected. libhugetlbfs will also work fine as usual. == Graceful fallback == Code walking pagetables but unware about huge pmds can simply call -split_huge_page_pmd(mm, pmd) where the pmd is the one returned by +split_huge_page_pmd(vma, addr, pmd) where the pmd is the one returned by pmd_offset. It's trivial to make the code transparent hugepage aware by just grepping for "pmd_offset" and adding split_huge_page_pmd where missing after pmd_offset returns the pmd. Thanks to the graceful @@ -299,7 +299,7 @@ diff --git a/mm/mremap.c b/mm/mremap.c return NULL; pmd = pmd_offset(pud, addr); -+ split_huge_page_pmd(mm, pmd); ++ split_huge_page_pmd(vma, addr, pmd); if (pmd_none_or_clear_bad(pmd)) return NULL; diff --git a/arch/x86/kernel/vm86_32.c b/arch/x86/kernel/vm86_32.c index 5c9687b1bde..1dfe69cc78a 100644 --- a/arch/x86/kernel/vm86_32.c +++ b/arch/x86/kernel/vm86_32.c @@ -182,7 +182,7 @@ static void mark_screen_rdonly(struct mm_struct *mm) if (pud_none_or_clear_bad(pud)) goto out; pmd = pmd_offset(pud, 0xA0000); - split_huge_page_pmd(mm, pmd); + split_huge_page_pmd_mm(mm, 0xA0000, pmd); if (pmd_none_or_clear_bad(pmd)) goto out; pte = pte_offset_map_lock(mm, pmd, 0xA0000, &ptl); diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c index 90c63f9392a..291a0d15a0b 100644 --- a/fs/proc/task_mmu.c +++ b/fs/proc/task_mmu.c @@ -643,7 +643,7 @@ static int clear_refs_pte_range(pmd_t *pmd, unsigned long addr, spinlock_t *ptl; struct page *page; - split_huge_page_pmd(walk->mm, pmd); + split_huge_page_pmd(vma, addr, pmd); if (pmd_trans_unstable(pmd)) return 0; diff --git a/include/linux/huge_mm.h b/include/linux/huge_mm.h index 1af47755245..3132ea78858 100644 --- a/include/linux/huge_mm.h +++ b/include/linux/huge_mm.h @@ -95,12 +95,14 @@ extern int handle_pte_fault(struct mm_struct *mm, struct vm_area_struct *vma, unsigned long address, pte_t *pte, pmd_t *pmd, unsigned int flags); extern int split_huge_page(struct page *page); -extern void __split_huge_page_pmd(struct mm_struct *mm, pmd_t *pmd); -#define split_huge_page_pmd(__mm, __pmd) \ +extern void __split_huge_page_pmd(struct vm_area_struct *vma, + unsigned long address, pmd_t *pmd); +#define split_huge_page_pmd(__vma, __address, __pmd) \ do { \ pmd_t *____pmd = (__pmd); \ if (unlikely(pmd_trans_huge(*____pmd))) \ - __split_huge_page_pmd(__mm, ____pmd); \ + __split_huge_page_pmd(__vma, __address, \ + ____pmd); \ } while (0) #define wait_split_huge_page(__anon_vma, __pmd) \ do { \ @@ -110,6 +112,8 @@ extern void __split_huge_page_pmd(struct mm_struct *mm, pmd_t *pmd); BUG_ON(pmd_trans_splitting(*____pmd) || \ pmd_trans_huge(*____pmd)); \ } while (0) +extern void split_huge_page_pmd_mm(struct mm_struct *mm, unsigned long address, + pmd_t *pmd); #if HPAGE_PMD_ORDER > MAX_ORDER #error "hugepages can't be allocated by the buddy allocator" #endif @@ -177,10 +181,12 @@ static inline int split_huge_page(struct page *page) { return 0; } -#define split_huge_page_pmd(__mm, __pmd) \ +#define split_huge_page_pmd(__vma, __address, __pmd) \ do { } while (0) #define wait_split_huge_page(__anon_vma, __pmd) \ do { } while (0) +#define split_huge_page_pmd_mm(__mm, __address, __pmd) \ + do { } while (0) #define compound_trans_head(page) compound_head(page) static inline int hugepage_madvise(struct vm_area_struct *vma, unsigned long *vm_flags, int advice) diff --git a/mm/huge_memory.c b/mm/huge_memory.c index 7742fb36eb4..de6aa5f3fdd 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -2475,9 +2475,14 @@ static int khugepaged(void *none) return 0; } -void __split_huge_page_pmd(struct mm_struct *mm, pmd_t *pmd) +void __split_huge_page_pmd(struct vm_area_struct *vma, unsigned long address, + pmd_t *pmd) { struct page *page; + unsigned long haddr = address & HPAGE_PMD_MASK; + struct mm_struct *mm = vma->vm_mm; + + BUG_ON(vma->vm_start > haddr || vma->vm_end < haddr + HPAGE_PMD_SIZE); spin_lock(&mm->page_table_lock); if (unlikely(!pmd_trans_huge(*pmd))) { @@ -2495,6 +2500,16 @@ void __split_huge_page_pmd(struct mm_struct *mm, pmd_t *pmd) BUG_ON(pmd_trans_huge(*pmd)); } +void split_huge_page_pmd_mm(struct mm_struct *mm, unsigned long address, + pmd_t *pmd) +{ + struct vm_area_struct *vma; + + vma = find_vma(mm, address); + BUG_ON(vma == NULL); + split_huge_page_pmd(vma, address, pmd); +} + static void split_huge_page_address(struct mm_struct *mm, unsigned long address) { @@ -2509,7 +2524,7 @@ static void split_huge_page_address(struct mm_struct *mm, * Caller holds the mmap_sem write mode, so a huge pmd cannot * materialize from under us. */ - split_huge_page_pmd(mm, pmd); + split_huge_page_pmd_mm(mm, address, pmd); } void __vma_adjust_trans_huge(struct vm_area_struct *vma, diff --git a/mm/memory.c b/mm/memory.c index 259b34fe134..f9a4b0cb862 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -1243,7 +1243,7 @@ static inline unsigned long zap_pmd_range(struct mmu_gather *tlb, BUG(); } #endif - split_huge_page_pmd(vma->vm_mm, pmd); + split_huge_page_pmd(vma, addr, pmd); } else if (zap_huge_pmd(tlb, vma, pmd, addr)) goto next; /* fall through */ @@ -1512,7 +1512,7 @@ struct page *follow_page(struct vm_area_struct *vma, unsigned long address, } if (pmd_trans_huge(*pmd)) { if (flags & FOLL_SPLIT) { - split_huge_page_pmd(mm, pmd); + split_huge_page_pmd(vma, address, pmd); goto split_fallthrough; } spin_lock(&mm->page_table_lock); diff --git a/mm/mempolicy.c b/mm/mempolicy.c index 05b28361a39..0719e8dd494 100644 --- a/mm/mempolicy.c +++ b/mm/mempolicy.c @@ -511,7 +511,7 @@ static inline int check_pmd_range(struct vm_area_struct *vma, pud_t *pud, pmd = pmd_offset(pud, addr); do { next = pmd_addr_end(addr, end); - split_huge_page_pmd(vma->vm_mm, pmd); + split_huge_page_pmd(vma, addr, pmd); if (pmd_none_or_trans_huge_or_clear_bad(pmd)) continue; if (check_pte_range(vma, pmd, addr, next, nodes, diff --git a/mm/mprotect.c b/mm/mprotect.c index a40992610ab..e8c3938db6f 100644 --- a/mm/mprotect.c +++ b/mm/mprotect.c @@ -90,7 +90,7 @@ static inline void change_pmd_range(struct vm_area_struct *vma, pud_t *pud, next = pmd_addr_end(addr, end); if (pmd_trans_huge(*pmd)) { if (next - addr != HPAGE_PMD_SIZE) - split_huge_page_pmd(vma->vm_mm, pmd); + split_huge_page_pmd(vma, addr, pmd); else if (change_huge_pmd(vma, pmd, addr, newprot)) continue; /* fall through */ diff --git a/mm/mremap.c b/mm/mremap.c index 1b61c2d3307..eabb24da6c9 100644 --- a/mm/mremap.c +++ b/mm/mremap.c @@ -182,7 +182,7 @@ unsigned long move_page_tables(struct vm_area_struct *vma, need_flush = true; continue; } else if (!err) { - split_huge_page_pmd(vma->vm_mm, old_pmd); + split_huge_page_pmd(vma, old_addr, old_pmd); } VM_BUG_ON(pmd_trans_huge(*old_pmd)); } diff --git a/mm/pagewalk.c b/mm/pagewalk.c index 6c118d012bb..35aa294656c 100644 --- a/mm/pagewalk.c +++ b/mm/pagewalk.c @@ -58,7 +58,7 @@ again: if (!walk->pte_entry) continue; - split_huge_page_pmd(walk->mm, pmd); + split_huge_page_pmd_mm(walk->mm, addr, pmd); if (pmd_none_or_trans_huge_or_clear_bad(pmd)) goto again; err = walk_pte_range(pmd, addr, next, walk);