From mboxrd@z Thu Jan 1 00:00:00 1970 From: Avi Kivity Subject: Re: assign-dev: Purpose of interrupt_work Date: Mon, 12 Oct 2009 11:16:54 +0200 Message-ID: <4AD2F406.9050108@redhat.com> References: <4AD2D4B6.7030203@web.de> <20091012071310.GT16702@redhat.com> <4AD2DA57.6030006@web.de> <20091012074513.GV16702@redhat.com> <4AD2DFE2.4050406@web.de> <4AD2EB2D.5080909@redhat.com> <4AD2F1D0.4090005@web.de> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: Gleb Natapov , kvm-devel To: Jan Kiszka Return-path: Received: from mx1.redhat.com ([209.132.183.28]:46227 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754797AbZJLJRW (ORCPT ); Mon, 12 Oct 2009 05:17:22 -0400 In-Reply-To: <4AD2F1D0.4090005@web.de> Sender: kvm-owner@vger.kernel.org List-ID: On 10/12/2009 11:07 AM, Jan Kiszka wrote: >> I'm worried about disabling irqs for non-device-assignment cases. It >> would be more palatable if ioapic was completely O(1) (there are some >> per-vcpu loops in there, shouldn't be too bad for 16 vcpus, but we want >> to scale). >> > Yeah, what a pity. That's likely not solvable in a generic way, given > that the guest finally decided how many VCPUs may listen to a line. > > OK, but dropping interrupt_work from the MSI path is still worthwhile, > and probably more future-proof anyway. > Yes - we can extend the irq routing table to contain this information. It means we need to invalidate it when the guest reprograms the interrupt controllers, but I think it should work out fine. -- error compiling committee.c: too many arguments to function