From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752743AbbIPTDl (ORCPT ); Wed, 16 Sep 2015 15:03:41 -0400 Received: from eu-smtp-delivery-143.mimecast.com ([146.101.78.143]:62433 "EHLO eu-smtp-delivery-143.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752169AbbIPTDk (ORCPT ); Wed, 16 Sep 2015 15:03:40 -0400 From: Jeremy Linton To: linux-arm-kernel@lists.infradead.org Cc: catalin.marinas@arm.com, will.deacon@arm.com, linux-kernel@vger.kernel.org, dwoods@ezcip.com, steve.capper@arm.com, shijie.huang@arm.com, Jeremy Linton Subject: [PATCH 0/7] arm64: Use contigous PTE bit for the kernel linear mapping Date: Wed, 16 Sep 2015 14:02:59 -0500 Message-Id: <1442430186-9083-1-git-send-email-jeremy.linton@arm.com> X-Mailer: git-send-email 2.4.3 X-OriginalArrivalTime: 16 Sep 2015 19:03:38.0134 (UTC) FILETIME=[64E55360:01D0F0B2] X-MC-Unique: 1W4AWgpJTPKDtJcpxVkt5g-1 Content-Type: text/plain; charset=WINDOWS-1252 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from quoted-printable to 8bit by mail.home.local id t8GJ3pON004278 When running 64k pages it became apparent that it was possible that the kernel could create more TLB pressure in certain circumstances when compared to the 4k page kernel. This is due to the fact that large portions of the 4k kernel can be mapped with 2M blocks. While the larger block size for 64k pages is 512M, it frequently won't be used for assorted reasons. ARMv8 has a contiguous PTE bit that allows the TLBs to map a range larger than a single PTE if the range is physically contiguous. So its a good idea to use this where appropriate for the kernel mapping. This patch adds the definitions for the contiguous bit, updates the kernel page range dump to understand them (and block translations), and updates the code in mmu.c to use the contiguous bit where appropriate for the kernel linear mapping. Jeremy Linton (7): arm64: Add contiguous page flag shifts and constants arm64: Shorten lines which exceed 80 characters arm64: PTE/PMD contiguous bit definition arm64: Macros to check/set/unset the contiguous bit arm64: Default kernel pages should be contiguous arm64: Make the kernel page dump utility aware of the CONT bit arm64: Mark kernel page ranges contiguous arch/arm64/include/asm/page.h | 8 +++- arch/arm64/include/asm/pgtable-hwdef.h | 25 ++++++++---- arch/arm64/include/asm/pgtable.h | 13 +++++++ arch/arm64/mm/dump.c | 18 ++++++++- arch/arm64/mm/mmu.c | 70 ++++++++++++++++++++++++++++++---- 5 files changed, 116 insertions(+), 18 deletions(-) -- 2.4.3