Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1762059AbYF0Rpd (ORCPT ); Fri, 27 Jun 2008 13:45:33 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1757436AbYF0RpU (ORCPT ); Fri, 27 Jun 2008 13:45:20 -0400 Received: from mtagate8.de.ibm.com ([195.212.29.157]:1370 "EHLO mtagate8.de.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756273AbYF0RpT (ORCPT ); Fri, 27 Jun 2008 13:45:19 -0400 Date: Fri, 27 Jun 2008 13:44:15 -0400 From: Muli Ben-Yehuda To: Joerg Roedel Cc: Andi Kleen , Adrian Bunk , Joerg Roedel , tglx@linutronix.de, mingo@redhat.com, linux-kernel@vger.kernel.org, iommu@lists.linux-foundation.org, bhavna.sarathy@amd.com, Sebastian.Biemueller@amd.com, robert.richter@amd.com, Ben-Ami Yassour1 Subject: Re: [PATCH 01/34] AMD IOMMU: add Kconfig entry Message-ID: <20080627174415.GF26130@il.ibm.com> References: <20080627142558.GG18644@cs181140183.pp.htv.fi> <878wwrq6im.fsf@basil.nowhere.org> <20080627163945.GA26130@il.ibm.com> <20080627165430.GD10197@8bytes.org> <20080627165947.GB26130@il.ibm.com> <20080627170546.GE10197@8bytes.org> <20080627171201.GC26130@il.ibm.com> <20080627172030.GF10197@8bytes.org> <20080627173100.GD26130@il.ibm.com> <20080627174034.GG10197@8bytes.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20080627174034.GG10197@8bytes.org> User-Agent: Mutt/1.5.15+20070412 (2007-04-11) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1073 Lines: 28 On Fri, Jun 27, 2008 at 07:40:35PM +0200, Joerg Roedel wrote: > Yes. As I said, this is for the non-isolating case. For the > isolation case (which is needed for protection) it is harder to > optimize. But there I think about some sort of lazy IOMMU TLB > flushing. The flushing and 'wait for the flush to finish' is the > most expensive part in the mapping and unmapping code path. But this > needs some experiments. Agreed. The paper I just posted to the iommu mailing list has some ideas and experimental data. > > I am thinking of them and I'd be surprised if you'd find any in > > such machines. Certainly I assume none of the on-board devices > > will have this ancient limitation. But hey, it could happen ;-) > > The IOMMU machine under my desk has a 32bit PCI slot with a card in > it :-) Touche :-) Cheers, Muli -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/