From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx146.postini.com [74.125.245.146]) by kanga.kvack.org (Postfix) with SMTP id E80546B006E for ; Fri, 19 Oct 2012 14:49:56 -0400 (EDT) Date: Fri, 19 Oct 2012 11:49:55 -0700 From: Andrew Morton Subject: Re: [PATCH v2] mm: thp: Set the accessed flag for old pages on access fault. Message-Id: <20121019114955.3a0c2b66.akpm@linux-foundation.org> In-Reply-To: <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> <20121019091016.GA4582@mudshark.cambridge.arm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Will Deacon 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 On Fri, 19 Oct 2012 10:10:16 +0100 Will Deacon wrote: > 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 I received and then merged a patch which won't compile! Ho hum. I'll drop mm-thp-set-the-accessed-flag-for-old-pages-on-access-fault.patch and shall assume that you'll sort things out at the appropriate time. -- 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