From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx169.postini.com [74.125.245.169]) by kanga.kvack.org (Postfix) with SMTP id 419536B006E for ; Tue, 2 Oct 2012 11:18:58 -0400 (EDT) From: "Kirill A. Shutemov" Subject: [PATCH v3 02/10] thp: zap_huge_pmd(): zap huge zero pmd Date: Tue, 2 Oct 2012 18:19:24 +0300 Message-Id: <1349191172-28855-3-git-send-email-kirill.shutemov@linux.intel.com> In-Reply-To: <1349191172-28855-1-git-send-email-kirill.shutemov@linux.intel.com> References: <1349191172-28855-1-git-send-email-kirill.shutemov@linux.intel.com> Sender: owner-linux-mm@kvack.org List-ID: To: Andrew Morton , linux-mm@kvack.org Cc: Andrea Arcangeli , Andi Kleen , "H. Peter Anvin" , linux-kernel@vger.kernel.org, "Kirill A. Shutemov" , "Kirill A. Shutemov" From: "Kirill A. Shutemov" We don't have a real page to zap in huge zero page case. Let's just clear pmd and remove it from tlb. Signed-off-by: Kirill A. Shutemov Reviewed-by: Andrea Arcangeli --- mm/huge_memory.c | 27 +++++++++++++++++---------- 1 files changed, 17 insertions(+), 10 deletions(-) diff --git a/mm/huge_memory.c b/mm/huge_memory.c index 50c44e9..140d858 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -1072,16 +1072,23 @@ int zap_huge_pmd(struct mmu_gather *tlb, struct vm_area_struct *vma, struct page *page; pgtable_t pgtable; pgtable = get_pmd_huge_pte(tlb->mm); - page = pmd_page(*pmd); - pmd_clear(pmd); - tlb_remove_pmd_tlb_entry(tlb, pmd, addr); - page_remove_rmap(page); - VM_BUG_ON(page_mapcount(page) < 0); - add_mm_counter(tlb->mm, MM_ANONPAGES, -HPAGE_PMD_NR); - VM_BUG_ON(!PageHead(page)); - tlb->mm->nr_ptes--; - spin_unlock(&tlb->mm->page_table_lock); - tlb_remove_page(tlb, page); + if (is_huge_zero_pmd(*pmd)) { + pmd_clear(pmd); + tlb_remove_pmd_tlb_entry(tlb, pmd, addr); + tlb->mm->nr_ptes--; + spin_unlock(&tlb->mm->page_table_lock); + } else { + page = pmd_page(*pmd); + pmd_clear(pmd); + tlb_remove_pmd_tlb_entry(tlb, pmd, addr); + page_remove_rmap(page); + VM_BUG_ON(page_mapcount(page) < 0); + add_mm_counter(tlb->mm, MM_ANONPAGES, -HPAGE_PMD_NR); + VM_BUG_ON(!PageHead(page)); + tlb->mm->nr_ptes--; + spin_unlock(&tlb->mm->page_table_lock); + tlb_remove_page(tlb, page); + } pte_free(tlb->mm, pgtable); ret = 1; } -- 1.7.7.6 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org