Messages in this thread | | | Date | Fri, 12 Oct 2012 13:00:39 +0800 | From | Ni zhan Chen <> | Subject | Re: [PATCH v3 07/10] thp: implement splitting pmd for huge zero page |
| |
On 10/12/2012 12:13 PM, Kirill A. Shutemov wrote: > On Fri, Oct 12, 2012 at 11:23:37AM +0800, Ni zhan Chen wrote: >> On 10/02/2012 11:19 PM, Kirill A. Shutemov wrote: >>> From: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> >>> >>> We can't split huge zero page itself, but we can split the pmd which >>> points to it. >>> >>> On splitting the pmd we create a table with all ptes set to normal zero >>> page. >>> >>> Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> >>> Reviewed-by: Andrea Arcangeli <aarcange@redhat.com> >>> --- >>> mm/huge_memory.c | 32 ++++++++++++++++++++++++++++++++ >>> 1 files changed, 32 insertions(+), 0 deletions(-) >>> >>> diff --git a/mm/huge_memory.c b/mm/huge_memory.c >>> index 95032d3..3f1c59c 100644 >>> --- a/mm/huge_memory.c >>> +++ b/mm/huge_memory.c >>> @@ -1600,6 +1600,7 @@ int split_huge_page(struct page *page) >>> struct anon_vma *anon_vma; >>> int ret = 1; >>> + BUG_ON(is_huge_zero_pfn(page_to_pfn(page))); >>> BUG_ON(!PageAnon(page)); >>> anon_vma = page_lock_anon_vma(page); >>> if (!anon_vma) >>> @@ -2503,6 +2504,32 @@ static int khugepaged(void *none) >>> return 0; >>> } >>> +static void __split_huge_zero_page_pmd(struct vm_area_struct *vma, >>> + unsigned long haddr, pmd_t *pmd) >>> +{ >>> + pgtable_t pgtable; >>> + pmd_t _pmd; >>> + int i; >>> + >>> + pmdp_clear_flush_notify(vma, haddr, pmd); >> why I can't find function pmdp_clear_flush_notify in kernel source >> code? Do you mean pmdp_clear_flush_young_notify or something like >> that? > It was changed recently. See commit > 2ec74c3 mm: move all mmu notifier invocations to be done outside the PT lock
Oh, thanks!
| |