From mboxrd@z Thu Jan 1 00:00:00 1970 From: Paolo Bonzini Subject: Re: [PATCH 05/13] KVM: Update IRTE according to guest interrupt configuration changes Date: Wed, 12 Nov 2014 10:56:26 +0100 Message-ID: <54632ECA.4070903@redhat.com> References: <5461EC99.1000101@redhat.com> <546324F4.8010002@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Errors-To: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org To: "Wu, Feng" , "Zhang, Yang Z" , Alex Williamson Cc: "kvm-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , "gleb-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org" , "x86-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org" , "linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , "iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org" , "mingo-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org" , "hpa-YMNOUZJC4hwAvxtiuMwx3w@public.gmane.org" , "tglx-hfZtesqFncYOwBW4kG4KsQ@public.gmane.org" , "dwmw2-wEGCiKHe2LqWVfeAwA7xHQ@public.gmane.org" List-Id: iommu@lists.linux-foundation.org On 12/11/2014 10:19, Wu, Feng wrote: >> You can certainly backport these patches to distros that do not have >> VFIO. But upstream we should work on VFIO first. VFIO has feature >> parity with legacy device assignment, and adding a new feature that is >> not in VFIO would be a bad idea. >> >> By the way, do you have benchmark results for it? We have not been able >> to see any performance improvement for APICv on e.g. netperf. > > Do you mean benchmark results for APICv itself or VT-d Posted-Interrtups? Especially for VT-d posted interrupts---but it'd be great to know which workloads see the biggest speedup from APICv. Paolo From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752298AbaKLJ5R (ORCPT ); Wed, 12 Nov 2014 04:57:17 -0500 Received: from mx1.redhat.com ([209.132.183.28]:37809 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751564AbaKLJ5O (ORCPT ); Wed, 12 Nov 2014 04:57:14 -0500 Message-ID: <54632ECA.4070903@redhat.com> Date: Wed, 12 Nov 2014 10:56:26 +0100 From: Paolo Bonzini User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.2.0 MIME-Version: 1.0 To: "Wu, Feng" , "Zhang, Yang Z" , Alex Williamson CC: "gleb@kernel.org" , "dwmw2@infradead.org" , "joro@8bytes.org" , "tglx@linutronix.de" , "mingo@redhat.com" , "hpa@zytor.com" , "x86@kernel.org" , "kvm@vger.kernel.org" , "iommu@lists.linux-foundation.org" , "linux-kernel@vger.kernel.org" Subject: Re: [PATCH 05/13] KVM: Update IRTE according to guest interrupt configuration changes References: <5461EC99.1000101@redhat.com> <546324F4.8010002@redhat.com> In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 12/11/2014 10:19, Wu, Feng wrote: >> You can certainly backport these patches to distros that do not have >> VFIO. But upstream we should work on VFIO first. VFIO has feature >> parity with legacy device assignment, and adding a new feature that is >> not in VFIO would be a bad idea. >> >> By the way, do you have benchmark results for it? We have not been able >> to see any performance improvement for APICv on e.g. netperf. > > Do you mean benchmark results for APICv itself or VT-d Posted-Interrtups? Especially for VT-d posted interrupts---but it'd be great to know which workloads see the biggest speedup from APICv. Paolo