From: Andrea Arcangeli Date: Thu, 13 Jan 2011 23:46:43 +0000 (-0800) Subject: thp: pte alloc trans splitting X-Git-Tag: v2.6.38-rc1~152 X-Git-Url: https://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=8ac1f8320a0073f28cf9e0491af4cd98f504f92a;p=pandora-kernel.git thp: pte alloc trans splitting pte alloc routines must wait for split_huge_page if the pmd is not present and not null (i.e. pmd_trans_splitting). The additional branches are optimized away at compile time by pmd_trans_splitting if the config option is off. However we must pass the vma down in order to know the anon_vma lock to wait for. [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Andrea Arcangeli Acked-by: Rik van Riel Acked-by: Mel Gorman Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- diff --git a/arch/arm/mm/pgd.c b/arch/arm/mm/pgd.c index 93292a18cf77..709244c66fa3 100644 --- a/arch/arm/mm/pgd.c +++ b/arch/arm/mm/pgd.c @@ -50,7 +50,7 @@ pgd_t *pgd_alloc(struct mm_struct *mm) if (!new_pmd) goto no_pmd; - new_pte = pte_alloc_map(mm, new_pmd, 0); + new_pte = pte_alloc_map(mm, NULL, new_pmd, 0); if (!new_pte) goto no_pte; diff --git a/arch/ia64/mm/hugetlbpage.c b/arch/ia64/mm/hugetlbpage.c index 1841ee7e65f9..5ca674b74737 100644 --- a/arch/ia64/mm/hugetlbpage.c +++ b/arch/ia64/mm/hugetlbpage.c @@ -38,7 +38,7 @@ huge_pte_alloc(struct mm_struct *mm, unsigned long addr, unsigned long sz) if (pud) { pmd = pmd_alloc(mm, pud, taddr); if (pmd) - pte = pte_alloc_map(mm, pmd, taddr); + pte = pte_alloc_map(mm, NULL, pmd, taddr); } return pte; } diff --git a/arch/sh/mm/hugetlbpage.c b/arch/sh/mm/hugetlbpage.c index 9163db3e8d15..d7762349ea48 100644 --- a/arch/sh/mm/hugetlbpage.c +++ b/arch/sh/mm/hugetlbpage.c @@ -35,7 +35,7 @@ pte_t *huge_pte_alloc(struct mm_struct *mm, if (pud) { pmd = pmd_alloc(mm, pud, addr); if (pmd) - pte = pte_alloc_map(mm, pmd, addr); + pte = pte_alloc_map(mm, NULL, pmd, addr); } } diff --git a/arch/sparc/mm/generic_32.c b/arch/sparc/mm/generic_32.c index 5edcac184eaf..e6067b75f11c 100644 --- a/arch/sparc/mm/generic_32.c +++ b/arch/sparc/mm/generic_32.c @@ -50,7 +50,7 @@ static inline int io_remap_pmd_range(struct mm_struct *mm, pmd_t * pmd, unsigned end = PGDIR_SIZE; offset -= address; do { - pte_t * pte = pte_alloc_map(mm, pmd, address); + pte_t *pte = pte_alloc_map(mm, NULL, pmd, address); if (!pte) return -ENOMEM; io_remap_pte_range(mm, pte, address, end - address, address + offset, prot, space); diff --git a/arch/sparc/mm/generic_64.c b/arch/sparc/mm/generic_64.c index 04f2bf4cd571..3cb00dfd4bd6 100644 --- a/arch/sparc/mm/generic_64.c +++ b/arch/sparc/mm/generic_64.c @@ -92,7 +92,7 @@ static inline int io_remap_pmd_range(struct mm_struct *mm, pmd_t * pmd, unsigned end = PGDIR_SIZE; offset -= address; do { - pte_t * pte = pte_alloc_map(mm, pmd, address); + pte_t *pte = pte_alloc_map(mm, NULL, pmd, address); if (!pte) return -ENOMEM; io_remap_pte_range(mm, pte, address, end - address, address + offset, prot, space); diff --git a/arch/sparc/mm/hugetlbpage.c b/arch/sparc/mm/hugetlbpage.c index 5fdddf134caa..f4e97646ce23 100644 --- a/arch/sparc/mm/hugetlbpage.c +++ b/arch/sparc/mm/hugetlbpage.c @@ -214,7 +214,7 @@ pte_t *huge_pte_alloc(struct mm_struct *mm, if (pud) { pmd = pmd_alloc(mm, pud, addr); if (pmd) - pte = pte_alloc_map(mm, pmd, addr); + pte = pte_alloc_map(mm, NULL, pmd, addr); } return pte; } diff --git a/arch/um/kernel/skas/mmu.c b/arch/um/kernel/skas/mmu.c index 3d099f974785..1aee587e9c5d 100644 --- a/arch/um/kernel/skas/mmu.c +++ b/arch/um/kernel/skas/mmu.c @@ -31,7 +31,7 @@ static int init_stub_pte(struct mm_struct *mm, unsigned long proc, if (!pmd) goto out_pmd; - pte = pte_alloc_map(mm, pmd, proc); + pte = pte_alloc_map(mm, NULL, pmd, proc); if (!pte) goto out_pte; diff --git a/arch/x86/kernel/tboot.c b/arch/x86/kernel/tboot.c index c2f1b26141e2..998e972f3b1a 100644 --- a/arch/x86/kernel/tboot.c +++ b/arch/x86/kernel/tboot.c @@ -133,7 +133,7 @@ static int map_tboot_page(unsigned long vaddr, unsigned long pfn, pmd = pmd_alloc(&tboot_mm, pud, vaddr); if (!pmd) return -1; - pte = pte_alloc_map(&tboot_mm, pmd, vaddr); + pte = pte_alloc_map(&tboot_mm, NULL, pmd, vaddr); if (!pte) return -1; set_pte_at(&tboot_mm, vaddr, pte, pfn_pte(pfn, prot)); diff --git a/include/linux/mm.h b/include/linux/mm.h index 6bef67d74adf..14ddd98b063f 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -1131,7 +1131,8 @@ static inline int __pmd_alloc(struct mm_struct *mm, pud_t *pud, int __pmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long address); #endif -int __pte_alloc(struct mm_struct *mm, pmd_t *pmd, unsigned long address); +int __pte_alloc(struct mm_struct *mm, struct vm_area_struct *vma, + pmd_t *pmd, unsigned long address); int __pte_alloc_kernel(pmd_t *pmd, unsigned long address); /* @@ -1200,16 +1201,18 @@ static inline void pgtable_page_dtor(struct page *page) pte_unmap(pte); \ } while (0) -#define pte_alloc_map(mm, pmd, address) \ - ((unlikely(!pmd_present(*(pmd))) && __pte_alloc(mm, pmd, address))? \ - NULL: pte_offset_map(pmd, address)) +#define pte_alloc_map(mm, vma, pmd, address) \ + ((unlikely(pmd_none(*(pmd))) && __pte_alloc(mm, vma, \ + pmd, address))? \ + NULL: pte_offset_map(pmd, address)) #define pte_alloc_map_lock(mm, pmd, address, ptlp) \ - ((unlikely(!pmd_present(*(pmd))) && __pte_alloc(mm, pmd, address))? \ + ((unlikely(pmd_none(*(pmd))) && __pte_alloc(mm, NULL, \ + pmd, address))? \ NULL: pte_offset_map_lock(mm, pmd, address, ptlp)) #define pte_alloc_kernel(pmd, address) \ - ((unlikely(!pmd_present(*(pmd))) && __pte_alloc_kernel(pmd, address))? \ + ((unlikely(pmd_none(*(pmd))) && __pte_alloc_kernel(pmd, address))? \ NULL: pte_offset_kernel(pmd, address)) extern void free_area_init(unsigned long * zones_size); diff --git a/mm/memory.c b/mm/memory.c index bdf19366b705..567bca80ea53 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -394,9 +394,11 @@ void free_pgtables(struct mmu_gather *tlb, struct vm_area_struct *vma, } } -int __pte_alloc(struct mm_struct *mm, pmd_t *pmd, unsigned long address) +int __pte_alloc(struct mm_struct *mm, struct vm_area_struct *vma, + pmd_t *pmd, unsigned long address) { pgtable_t new = pte_alloc_one(mm, address); + int wait_split_huge_page; if (!new) return -ENOMEM; @@ -416,14 +418,18 @@ int __pte_alloc(struct mm_struct *mm, pmd_t *pmd, unsigned long address) smp_wmb(); /* Could be smp_wmb__xxx(before|after)_spin_lock */ spin_lock(&mm->page_table_lock); - if (!pmd_present(*pmd)) { /* Has another populated it ? */ + wait_split_huge_page = 0; + if (likely(pmd_none(*pmd))) { /* Has another populated it ? */ mm->nr_ptes++; pmd_populate(mm, pmd, new); new = NULL; - } + } else if (unlikely(pmd_trans_splitting(*pmd))) + wait_split_huge_page = 1; spin_unlock(&mm->page_table_lock); if (new) pte_free(mm, new); + if (wait_split_huge_page) + wait_split_huge_page(vma->anon_vma, pmd); return 0; } @@ -436,10 +442,11 @@ int __pte_alloc_kernel(pmd_t *pmd, unsigned long address) smp_wmb(); /* See comment in __pte_alloc */ spin_lock(&init_mm.page_table_lock); - if (!pmd_present(*pmd)) { /* Has another populated it ? */ + if (likely(pmd_none(*pmd))) { /* Has another populated it ? */ pmd_populate_kernel(&init_mm, pmd, new); new = NULL; - } + } else + VM_BUG_ON(pmd_trans_splitting(*pmd)); spin_unlock(&init_mm.page_table_lock); if (new) pte_free_kernel(&init_mm, new); @@ -3253,7 +3260,7 @@ int handle_mm_fault(struct mm_struct *mm, struct vm_area_struct *vma, pmd = pmd_alloc(mm, pud, address); if (!pmd) return VM_FAULT_OOM; - pte = pte_alloc_map(mm, pmd, address); + pte = pte_alloc_map(mm, vma, pmd, address); if (!pte) return VM_FAULT_OOM; diff --git a/mm/mremap.c b/mm/mremap.c index 563fbdd6293a..b09eefaea0b8 100644 --- a/mm/mremap.c +++ b/mm/mremap.c @@ -47,7 +47,8 @@ static pmd_t *get_old_pmd(struct mm_struct *mm, unsigned long addr) return pmd; } -static pmd_t *alloc_new_pmd(struct mm_struct *mm, unsigned long addr) +static pmd_t *alloc_new_pmd(struct mm_struct *mm, struct vm_area_struct *vma, + unsigned long addr) { pgd_t *pgd; pud_t *pud; @@ -62,7 +63,8 @@ static pmd_t *alloc_new_pmd(struct mm_struct *mm, unsigned long addr) if (!pmd) return NULL; - if (!pmd_present(*pmd) && __pte_alloc(mm, pmd, addr)) + VM_BUG_ON(pmd_trans_huge(*pmd)); + if (pmd_none(*pmd) && __pte_alloc(mm, vma, pmd, addr)) return NULL; return pmd; @@ -147,7 +149,7 @@ unsigned long move_page_tables(struct vm_area_struct *vma, old_pmd = get_old_pmd(vma->vm_mm, old_addr); if (!old_pmd) continue; - new_pmd = alloc_new_pmd(vma->vm_mm, new_addr); + new_pmd = alloc_new_pmd(vma->vm_mm, vma, new_addr); if (!new_pmd) break; next = (new_addr + PMD_SIZE) & PMD_MASK;