From: "Michael S. Tsirkin" Subject: Re: [PATCH 0/2] eventfd: new EFD_STATE flag Date: Thu, 20 Aug 2009 21:28:47 +0300 Message-ID: <20090820182847.GB9282@redhat.com> References: <20090820155655.GA8764@redhat.com> <4A8D8A28.2050004@redhat.com> <20090820175540.GA9232@redhat.com> <4A8D90BB.2030506@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Davide Libenzi , gleb@redhat.com, kvm@vger.kernel.org, Linux Kernel Mailing List To: Avi Kivity Return-path: Received: from mx1.redhat.com ([209.132.183.28]:54418 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755214AbZHTSaK (ORCPT ); Thu, 20 Aug 2009 14:30:10 -0400 Content-Disposition: inline In-Reply-To: <4A8D90BB.2030506@redhat.com> Sender: kvm-owner@vger.kernel.org List-ID: On Thu, Aug 20, 2009 at 09:06:51PM +0300, Avi Kivity wrote: > On 08/20/2009 08:55 PM, Michael S. Tsirkin wrote: >> >>> While we could argue about this my feeling is that we should drop this, >>> at least until we can quantify what benefit it has and whether there are >>> any Davide-acceptable alternatives. >>> >>> In the meanwhile, we can let vhost-net support edge-triggered interrupts >>> only, let qemu terminate those eventfds and convert then to >>> level-triggered interrupts (which it can then inject using the existing >>> ioctl). It will keep vhost-net and kvm simpler at the cost of some >>> performance penalty to guests using level interrupts. These suck anyway >>> so we'll point users at msi. >>> >> I thought the point was to move assigned devices out of KVM? >> > > Grr. Forgot about that. > > That's much more important. Looks like we'll have do with a separate char device or something? > -- > I have a truly marvellous patch that fixes the bug which this > signature is too narrow to contain.