From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753756Ab2GRKml (ORCPT ); Wed, 18 Jul 2012 06:42:41 -0400 Received: from mx1.redhat.com ([209.132.183.28]:54091 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752464Ab2GRKmh (ORCPT ); Wed, 18 Jul 2012 06:42:37 -0400 Date: Wed, 18 Jul 2012 13:43:08 +0300 From: "Michael S. Tsirkin" To: Alex Williamson Cc: avi@redhat.com, gleb@redhat.com, kvm@vger.kernel.org, linux-kernel@vger.kernel.org, jan.kiszka@siemens.com Subject: Re: [PATCH v5 0/4] kvm: level irqfd and new eoifd Message-ID: <20120718104308.GD4700@redhat.com> References: <20120716202711.1752.71007.stgit@bling.home> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20120716202711.1752.71007.stgit@bling.home> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Jul 16, 2012 at 02:33:38PM -0600, Alex Williamson wrote: > v5: > - irqfds now have a one-to-one mapping with eoifds to prevent users > from consuming all of kernel memory by repeatedly creating eoifds > from a single irqfd. > - implement a kvm_clear_irq() which does a test_and_clear_bit of > the irq_state, only updating the pic/ioapic if changes and allowing > the caller to know if anything was done. I added this onto the end > as it's essentially an optimization on the previous design. It's > hard to tell if there's an actual performance benefit to this. I have to agree to this, but we need to avoid invoking kvm_set_irq in atomic context, without introducing sprurious eois. Can bool + spinlock that previous patch has be replaced by an atomic? > - dropped eoifd gsi support patch as it was only an FYI. > > Thanks, > > Alex > > --- > > Alex Williamson (4): > kvm: Convert eoifd to use kvm_clear_irq > kvm: Create kvm_clear_irq() > kvm: KVM_EOIFD, an eventfd for EOIs > kvm: Extend irqfd to support level interrupts > > > Documentation/virtual/kvm/api.txt | 28 +++ > arch/x86/kvm/x86.c | 3 > include/linux/kvm.h | 18 ++ > include/linux/kvm_host.h | 16 ++ > virt/kvm/eventfd.c | 333 +++++++++++++++++++++++++++++++++++++ > virt/kvm/irq_comm.c | 78 +++++++++ > virt/kvm/kvm_main.c | 11 + > 7 files changed, 483 insertions(+), 4 deletions(-)