From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758019Ab2JSJKn (ORCPT ); Fri, 19 Oct 2012 05:10:43 -0400 Received: from cam-admin0.cambridge.arm.com ([217.140.96.50]:45369 "EHLO cam-admin0.cambridge.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753881Ab2JSJKl (ORCPT ); Fri, 19 Oct 2012 05:10:41 -0400 Date: Fri, 19 Oct 2012 10:10:16 +0100 From: Will Deacon To: Andrew Morton Cc: David Miller , "linux-mm@kvack.org" , "linux-kernel@vger.kernel.org" , "linux-arch@vger.kernel.org" , "mhocko@suse.cz" , "kirill@shutemov.name" , "aarcange@redhat.com" , "cmetcalf@tilera.com" , Steve Capper Subject: Re: [PATCH v2] mm: thp: Set the accessed flag for old pages on access fault. Message-ID: <20121019091016.GA4582@mudshark.cambridge.arm.com> References: <1349197151-19645-1-git-send-email-will.deacon@arm.com> <20121002150104.da57fa94.akpm@linux-foundation.org> <20121017130125.GH5973@mudshark.cambridge.arm.com> <20121017.112620.1865348978594874782.davem@davemloft.net> <20121017155401.GJ5973@mudshark.cambridge.arm.com> <20121018150502.3dee7899.akpm@linux-foundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20121018150502.3dee7899.akpm@linux-foundation.org> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Oct 18, 2012 at 11:05:02PM +0100, Andrew Morton wrote: > On Wed, 17 Oct 2012 16:54:02 +0100 > Will Deacon wrote: > > > On x86 memory accesses to pages without the ACCESSED flag set result in the > > ACCESSED flag being set automatically. With the ARM architecture a page access > > fault is raised instead (and it will continue to be raised until the ACCESSED > > flag is set for the appropriate PTE/PMD). > > > > For normal memory pages, handle_pte_fault will call pte_mkyoung (effectively > > setting the ACCESSED flag). For transparent huge pages, pmd_mkyoung will only > > be called for a write fault. > > > > This patch ensures that faults on transparent hugepages which do not result > > in a CoW update the access flags for the faulting pmd. > > Confused. Where is the arm implementation of update_mmu_cache_pmd()? Right at the end of this patch, which was posted to the ARM list yesterday: http://lists.infradead.org/pipermail/linux-arm-kernel/2012-October/126387.html Cheers, Will