From 0013572b2ae535bfd6314f22d9aef53725ea00d8 Mon Sep 17 00:00:00 2001 From: Zachary Amsden Date: Sun, 6 May 2007 14:49:20 -0700 Subject: [PATCH] i386: use pte_update_defer in ptep_test_and_clear_{dirty,young} If you actually clear the bit, you need to: + pte_update_defer(vma->vm_mm, addr, ptep); The reason is, when updating PTEs, the hypervisor must be notified. Using atomic operations to do this is fine for all hypervisors I am aware of. However, for hypervisors which shadow page tables, if these PTE modifications are not trapped, you need a post-modification call to fulfill the update of the shadow page table. Acked-by: Zachary Amsden Cc: Hugh Dickins Signed-off-by: David Rientjes Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/asm-i386/pgtable.h | 38 ++++++++++++++++++-------------------- 1 file changed, 18 insertions(+), 20 deletions(-) diff --git a/include/asm-i386/pgtable.h b/include/asm-i386/pgtable.h index 995e8b34efd0..e16359f81a40 100644 --- a/include/asm-i386/pgtable.h +++ b/include/asm-i386/pgtable.h @@ -297,22 +297,24 @@ do { \ } while (0) #define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_DIRTY -static inline int ptep_test_and_clear_dirty(struct vm_area_struct *vma, - unsigned long addr, pte_t *ptep) -{ - if (!pte_dirty(*ptep)) - return 0; - return test_and_clear_bit(_PAGE_BIT_DIRTY, &ptep->pte_low); -} +#define ptep_test_and_clear_dirty(vma, addr, ptep) ({ \ + int ret = 0; \ + if (pte_dirty(*ptep)) \ + ret = test_and_clear_bit(_PAGE_BIT_DIRTY, &ptep->pte_low); \ + if (ret) \ + pte_update_defer(vma->vm_mm, addr, ptep); \ + ret; \ +}) #define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG -static inline int ptep_test_and_clear_young(struct vm_area_struct *vma, - unsigned long addr, pte_t *ptep) -{ - if (!pte_young(*ptep)) - return 0; - return test_and_clear_bit(_PAGE_BIT_ACCESSED, &ptep->pte_low); -} +#define ptep_test_and_clear_young(vma, addr, ptep) ({ \ + int ret = 0; \ + if (pte_young(*ptep)) \ + ret = test_and_clear_bit(_PAGE_BIT_ACCESSED, &ptep->pte_low); \ + if (ret) \ + pte_update_defer(vma->vm_mm, addr, ptep); \ + ret; \ +}) /* * Rules for using ptep_establish: the pte MUST be a user pte, and @@ -330,10 +332,8 @@ do { \ ({ \ int __dirty; \ __dirty = ptep_test_and_clear_dirty((vma), (address), (ptep)); \ - if (__dirty) { \ - pte_update_defer((vma)->vm_mm, (address), (ptep)); \ + if (__dirty) \ flush_tlb_page(vma, address); \ - } \ __dirty; \ }) @@ -342,10 +342,8 @@ do { \ ({ \ int __young; \ __young = ptep_test_and_clear_young((vma), (address), (ptep)); \ - if (__young) { \ - pte_update_defer((vma)->vm_mm, (address), (ptep)); \ + if (__young) \ flush_tlb_page(vma, address); \ - } \ __young; \ }) -- 2.20.1