From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753271AbYJTX5E (ORCPT ); Mon, 20 Oct 2008 19:57:04 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752257AbYJTX4w (ORCPT ); Mon, 20 Oct 2008 19:56:52 -0400 Received: from home.keithp.com ([63.227.221.253]:33937 "EHLO keithp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752155AbYJTX4w (ORCPT ); Mon, 20 Oct 2008 19:56:52 -0400 Subject: Re: io resources and cached mappings (was: [git pull] drm patches for 2.6.27-rc1) From: Keith Packard To: Ingo Molnar Cc: keithp@keithp.com, Jesse Barnes , Nick Piggin , Dave Airlie , Yinghai Lu , Linux Kernel Mailing List , dri-devel@lists.sf.net, Andrew Morton , Linus Torvalds In-Reply-To: <20081020115810.GC10594@elte.hu> References: <200810181237.49784.nickpiggin@yahoo.com.au> <1224357062.4384.72.camel@koto.keithp.com> <20081018203741.GA23396@elte.hu> <1224366690.4384.89.camel@koto.keithp.com> <20081018223214.GA5093@elte.hu> <1224389697.4384.118.camel@koto.keithp.com> <1224398496.5303.7.camel@koto.keithp.com> <20081019175320.GA6442@elte.hu> <1224450291.5303.23.camel@koto.keithp.com> <20081020115810.GC10594@elte.hu> Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="=-83If55+YSbYxxbEIri2Z" Date: Mon, 20 Oct 2008 08:49:04 -0700 Message-Id: <1224517744.5195.1.camel@koto.keithp.com> Mime-Version: 1.0 X-Mailer: Evolution 2.22.3.1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --=-83If55+YSbYxxbEIri2Z Content-Type: text/plain Content-Transfer-Encoding: quoted-printable On Mon, 2008-10-20 at 13:58 +0200, Ingo Molnar wrote: > yes but note that by caching the whole mapping on 64-bit we get=20 > everything we want: trivially lockless, works from any CPU, can be=20 > preempted at will, and there are no ugly INVLPG flushes anywhere. I was assuming that on 64-bit, the map would be created at driver init time and be left in place until the driver closed; if that's what you mean by 'caching', then yes, we should cache the map. > 32-bit we should handle as well but not design for it. As long as we get kmap_atomic-like performance, and we get to simplify our code, I'm up for it. --=20 keith.packard@intel.com --=-83If55+YSbYxxbEIri2Z Content-Type: application/pgp-signature; name=signature.asc Content-Description: This is a digitally signed message part -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.9 (GNU/Linux) iD8DBQBI/KhtQp8BWwlsTdMRAiDfAJ9RqvKfPpe18kPdy3zRgjQlcPTmuACcCAiZ GBlELYIpxLkB6bFJ5B5vW+Q= =6V02 -----END PGP SIGNATURE----- --=-83If55+YSbYxxbEIri2Z--