From mboxrd@z Thu Jan 1 00:00:00 1970 From: Avi Kivity Subject: Re: [PATCH 4/4][RFC] kvm: eoi_eventfd Date: Thu, 28 Jun 2012 19:27:55 +0300 Message-ID: <4FEC860B.3090605@redhat.com> References: <20120622220040.9858.43665.stgit@bling.home> <20120622221626.9858.33817.stgit@bling.home> <4FE70E99.90609@redhat.com> <1340550156.14120.53.camel@bling.home> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Cc: kvm@vger.kernel.org, linux-kernel@vger.kernel.org, jan.kiszka@siemens.com, mst@redhat.com To: Alex Williamson Return-path: In-Reply-To: <1340550156.14120.53.camel@bling.home> Sender: linux-kernel-owner@vger.kernel.org List-Id: kvm.vger.kernel.org On 06/24/2012 06:02 PM, Alex Williamson wrote: > On Sun, 2012-06-24 at 15:56 +0300, Avi Kivity wrote: >> On 06/23/2012 01:16 AM, Alex Williamson wrote: >> > I think we're probably also going to need something like this. >> > When running in non-accelerated qemu, we're going to have to >> > create some kind of EOI notifier for drivers. VFIO can make >> > additional improvements when running on KVM so it will probably >> > make use of the KVM_IRQFD_LEVEL_EOI interface, but we don't >> > want to have a generic EOI notifier in qemu that just stops >> > working when kvm-ioapic is enabled. >> >> Why? > > Hmm, I must be missing something or not describing it correctly, because > it seems obvious. I have not exhausted this quarter's quota of stupid questions yet. > If we create a dependency in qemu of needing to know > when an eoi occurs and notifier a driver and have no way to fulfill that > dependency when running on kvm... that'd be bad, right? I don't want to > assume that every consumer of such an interface would prefer to make use > of an irqfd. Not sure if that answers your question though. Thanks, I meant, what scenario do you have in mind where we want the EOI notifier while running with kvm-irqchip enabled? Perhaps I phrased my question a bit too tersely. -- error compiling committee.c: too many arguments to function