From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Michael S. Tsirkin" Subject: Re: [PATCHv4 0/2] kvm: direct msix injection Date: Wed, 21 Nov 2012 21:26:35 +0200 Message-ID: <20121121192635.GA9268@redhat.com> References: Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Jan Kiszka , Alex Williamson To: kvm@vger.kernel.org Return-path: Received: from mx1.redhat.com ([209.132.183.28]:50340 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755768Ab2KUTXs (ORCPT ); Wed, 21 Nov 2012 14:23:48 -0500 Content-Disposition: inline In-Reply-To: Sender: kvm-owner@vger.kernel.org List-ID: On Wed, Oct 17, 2012 at 06:05:53PM +0200, Michael S. Tsirkin wrote: > We can deliver certain interrupts, notably MSIX, > from atomic context. > Here's an untested patch to do this (compiled only). > > Changes from v2: > Don't inject broadcast interrupts directly > Changes from v1: > Tried to address comments from v1, except unifying > with kvm_set_irq: passing flags to it looks too ugly. > Added a comment. > > Jan, you said you can test this? I have tested this with some networking workloads and this patchset seems to work fine. My setup isn't a good fit for benchmarking device assignment though. Alex, could you pls verifyu that this solves the latency issue that you sometimes observe? With this patchset device assignment latency should be as fast as vfio. > > Michael S. Tsirkin (2): > kvm: add kvm_set_irq_inatomic > kvm: deliver msi interrupts from irq handler > > include/linux/kvm_host.h | 1 + > virt/kvm/assigned-dev.c | 36 +++++++++++++++------ > virt/kvm/irq_comm.c | 83 +++++++++++++++++++++++++++++++++++++++++------- > 3 files changed, 98 insertions(+), 22 deletions(-) > > -- > MST