From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758484AbbDWVEe (ORCPT ); Thu, 23 Apr 2015 17:04:34 -0400 Received: from mga11.intel.com ([192.55.52.93]:30745 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752170AbbDWVE1 (ORCPT ); Thu, 23 Apr 2015 17:04:27 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.11,634,1422950400"; d="scan'208";a="699994381" From: "Kirill A. Shutemov" To: Andrew Morton , Andrea Arcangeli , Hugh Dickins Cc: Dave Hansen , Mel Gorman , Rik van Riel , Vlastimil Babka , Christoph Lameter , Naoya Horiguchi , Steve Capper , "Aneesh Kumar K.V" , Johannes Weiner , Michal Hocko , Jerome Marchand , Sasha Levin , linux-kernel@vger.kernel.org, linux-mm@kvack.org, "Kirill A. Shutemov" Subject: [PATCHv5 08/28] khugepaged: ignore pmd tables with THP mapped with ptes Date: Fri, 24 Apr 2015 00:03:43 +0300 Message-Id: <1429823043-157133-9-git-send-email-kirill.shutemov@linux.intel.com> X-Mailer: git-send-email 2.1.4 In-Reply-To: <1429823043-157133-1-git-send-email-kirill.shutemov@linux.intel.com> References: <1429823043-157133-1-git-send-email-kirill.shutemov@linux.intel.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Prepare khugepaged to see compound pages mapped with pte. For now we won't collapse the pmd table with such pte. khugepaged is subject for future rework wrt new refcounting. Signed-off-by: Kirill A. Shutemov Tested-by: Sasha Levin --- mm/huge_memory.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/mm/huge_memory.c b/mm/huge_memory.c index fa3d4f78b716..ffc30e4462c1 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -2653,6 +2653,11 @@ static int khugepaged_scan_pmd(struct mm_struct *mm, page = vm_normal_page(vma, _address, pteval); if (unlikely(!page)) goto out_unmap; + + /* TODO: teach khugepaged to collapse THP mapped with pte */ + if (PageCompound(page)) + goto out_unmap; + /* * Record which node the original page is from and save this * information to khugepaged_node_load[]. @@ -2663,7 +2668,6 @@ static int khugepaged_scan_pmd(struct mm_struct *mm, if (khugepaged_scan_abort(node)) goto out_unmap; khugepaged_node_load[node]++; - VM_BUG_ON_PAGE(PageCompound(page), page); if (!PageLRU(page) || PageLocked(page) || !PageAnon(page)) goto out_unmap; /* -- 2.1.4