Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755793AbcKNGHp (ORCPT ); Mon, 14 Nov 2016 01:07:45 -0500 Received: from mail-pf0-f195.google.com ([209.85.192.195]:33189 "EHLO mail-pf0-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751662AbcKNGHo (ORCPT ); Mon, 14 Nov 2016 01:07:44 -0500 Subject: Re: [PATCH V3 1/2] mm: move vma_is_anonymous check within pmd_move_must_withdraw To: "Aneesh Kumar K.V" , akpm@linux-foundation.org, benh@au1.ibm.com, michaele@au1.ibm.com, michael.neuling@au1.ibm.com, paulus@au1.ibm.com, "Kirill A . Shutemov" References: <20161113150025.17942-1-aneesh.kumar@linux.vnet.ibm.com> Cc: linux-mm@kvack.org, linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org From: Balbir Singh Message-ID: Date: Mon, 14 Nov 2016 17:07:37 +1100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.0 MIME-Version: 1.0 In-Reply-To: <20161113150025.17942-1-aneesh.kumar@linux.vnet.ibm.com> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 766 Lines: 22 On 14/11/16 02:00, Aneesh Kumar K.V wrote: > Architectures like ppc64 want to use page table deposit/withraw > even with huge pmd dax entries. Allow arch to override the > vma_is_anonymous check by moving that to pmd_move_must_withdraw > function > I think the changelog can be reworded a bit Independent of whether the vma is for anonymous memory, some arches like ppc64 would like to override pmd_move_must_withdraw(). One option is to encapsulate the vma_is_anonymous() check for general architectures inside pmd_move_must_withdraw() so that is always called and architectures that need unconditional overriding can override this function. ppc64 needs to override the function when the MMU is configured to use hash PTE's. What do you think? Balbir Singh.