From mboxrd@z Thu Jan 1 00:00:00 1970 From: Marcelo Tosatti Subject: Re: [v3 21/26] x86, irq: Define a global vector for VT-d Posted-Interrupts Date: Mon, 23 Feb 2015 19:04:57 -0300 Message-ID: <20150223220457.GA9544@amt.cnet> References: <1418397300-10870-1-git-send-email-feng.wu@intel.com> <1418397300-10870-22-git-send-email-feng.wu@intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: <1418397300-10870-22-git-send-email-feng.wu-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org> 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: Feng Wu Cc: kvm-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, eric.auger-QSEj5FYQhm4dnm+yROfE0A@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, pbonzini-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, tglx-hfZtesqFncYOwBW4kG4KsQ@public.gmane.org, dwmw2-wEGCiKHe2LqWVfeAwA7xHQ@public.gmane.org, jiang.liu-VuQAYsv1563Yd54FQh9/CA@public.gmane.org List-Id: iommu@lists.linux-foundation.org On Fri, Dec 12, 2014 at 11:14:55PM +0800, Feng Wu wrote: > Currently, we use a global vector as the Posted-Interrupts > Notification Event for all the vCPUs in the system. We need > to introduce another global vector for VT-d Posted-Interrtups, > which will be used to wakeup the sleep vCPU when an external > interrupt from a direct-assigned device happens for that vCPU. > > Signed-off-by: Feng Wu Why an additional vector is necessary? Can't you simply wakeup the vcpu from kvm_posted_intr_ipi, the posted interrupt vector handler ? From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752489AbbBWWF5 (ORCPT ); Mon, 23 Feb 2015 17:05:57 -0500 Received: from mx1.redhat.com ([209.132.183.28]:45305 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751995AbbBWWFz (ORCPT ); Mon, 23 Feb 2015 17:05:55 -0500 Date: Mon, 23 Feb 2015 19:04:57 -0300 From: Marcelo Tosatti To: Feng Wu Cc: tglx@linutronix.de, mingo@redhat.com, hpa@zytor.com, x86@kernel.org, gleb@kernel.org, pbonzini@redhat.com, dwmw2@infradead.org, joro@8bytes.org, alex.williamson@redhat.com, jiang.liu@linux.intel.com, eric.auger@linaro.org, linux-kernel@vger.kernel.org, iommu@lists.linux-foundation.org, kvm@vger.kernel.org Subject: Re: [v3 21/26] x86, irq: Define a global vector for VT-d Posted-Interrupts Message-ID: <20150223220457.GA9544@amt.cnet> References: <1418397300-10870-1-git-send-email-feng.wu@intel.com> <1418397300-10870-22-git-send-email-feng.wu@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1418397300-10870-22-git-send-email-feng.wu@intel.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Dec 12, 2014 at 11:14:55PM +0800, Feng Wu wrote: > Currently, we use a global vector as the Posted-Interrupts > Notification Event for all the vCPUs in the system. We need > to introduce another global vector for VT-d Posted-Interrtups, > which will be used to wakeup the sleep vCPU when an external > interrupt from a direct-assigned device happens for that vCPU. > > Signed-off-by: Feng Wu Why an additional vector is necessary? Can't you simply wakeup the vcpu from kvm_posted_intr_ipi, the posted interrupt vector handler ?