From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sasha Levin Subject: ioeventfd question Date: Thu, 26 May 2011 22:03:40 +0300 Message-ID: <1306436620.3065.43.camel@lappy> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: kvm , Ingo Molnar , Pekka Enberg , Asias He , Prasad Joshi , Cyrill Gorcunov To: Avi Kivity Return-path: Received: from mail-ww0-f42.google.com ([74.125.82.42]:52221 "EHLO mail-ww0-f42.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932472Ab1EZTDo (ORCPT ); Thu, 26 May 2011 15:03:44 -0400 Received: by wwk4 with SMTP id 4so4762227wwk.1 for ; Thu, 26 May 2011 12:03:43 -0700 (PDT) Sender: kvm-owner@vger.kernel.org List-ID: Hi Avi, I'm working on adding ioeventfd support into tools/kvm/. Currently the implementation creates ioeventfd entries at the 'VIRTIO_PCI_QUEUE_NOTIFY' of each device and waits on all of them using epoll(). The basics are working - when IO is triggered I receive a notification using the event instead of an exit. I couldn't find a way to retrieve the value written to the PIO port - the guest memory at that location doesn't change, 'reading' the event just returns 1 (as expected) and I couldn't find anything else which might suggest what value was written to the PIO port. This is an issue with devices which have multiple virtio-rings, such as virtio-net. -- Sasha.