From mboxrd@z Thu Jan 1 00:00:00 1970 From: Paolo Bonzini Subject: Re: [v3 13/26] KVM: Define a new interface kvm_find_dest_vcpu() for VT-d PI Date: Mon, 22 Dec 2014 12:06:56 +0100 Message-ID: <5497FB50.1080606@redhat.com> References: <1418397300-10870-1-git-send-email-feng.wu@intel.com> <1418397300-10870-14-git-send-email-feng.wu@intel.com> <549307A5.3060305@redhat.com> <5494131E.9030505@redhat.com> <549576C7.4030800@redhat.com> <5497E41F.50301@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: "iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org" , "linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , KVM list , Eric Auger To: "Wu, Feng" , "Zhang, Yang Z" , Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , "x86-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org" , Gleb Natapov , "dwmw2-wEGCiKHe2LqWVfeAwA7xHQ@public.gmane.org" , "joro-zLv9SwRftAIdnm+yROfE0A@public.gmane.org" , Alex Williamson , Jiang Liu 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 List-Id: kvm.vger.kernel.org On 22/12/2014 12:04, Wu, Feng wrote: > > Can you support them only if the destination is a single CPU? > > Sorry, I am not quite understand this. I still don't understand the "single CPU" here. > Lowest priority interrupts always have a cpumask which contains multiple CPU. Yes, and those need not be accelerated. But what if you set affinity to a single CPU? Paolo