From mboxrd@z Thu Jan 1 00:00:00 1970 From: Avi Kivity Subject: Re: [RFC][PATCH 1/3] Introduce a workqueue to deliver PIT timer interrupts. Date: Wed, 09 Jun 2010 17:20:28 +0300 Message-ID: <4C0FA32C.7080001@redhat.com> References: <1276019703-18136-1-git-send-email-clalance@redhat.com> <1276019703-18136-2-git-send-email-clalance@redhat.com> <20100609134952.GB7396@amt.cnet> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: Chris Lalancette , kvm@vger.kernel.org To: Marcelo Tosatti Return-path: Received: from mx1.redhat.com ([209.132.183.28]:4140 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756919Ab0FIOUa (ORCPT ); Wed, 9 Jun 2010 10:20:30 -0400 Received: from int-mx03.intmail.prod.int.phx2.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.16]) by mx1.redhat.com (8.13.8/8.13.8) with ESMTP id o59EKUie030835 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK) for ; Wed, 9 Jun 2010 10:20:30 -0400 Received: from cleopatra.tlv.redhat.com (cleopatra.tlv.redhat.com [10.35.255.11]) by int-mx03.intmail.prod.int.phx2.redhat.com (8.13.8/8.13.8) with ESMTP id o59EKTZ5026252 for ; Wed, 9 Jun 2010 10:20:29 -0400 In-Reply-To: <20100609134952.GB7396@amt.cnet> Sender: kvm-owner@vger.kernel.org List-ID: On 06/09/2010 04:49 PM, Marcelo Tosatti wrote: > > Certain guests do not compensate for lost ticks (older RHEL3 for ex), > and this completly reinjection. > > Perhaps you can increase the pending counter on pit_timer_fn, and > reinject on ACK? > > Also, due to > http://www.mail-archive.com/kvm-devel@lists.sourceforge.net/msg13250.html, > it should be safer to keep PIT locked to vcpu0 if IOAPIC dest mode is > lowprio. > > Yes. We don't actually need to lock the PIT to vcpu 0, instead just make sure the lowprio selection picks vcpu 0 for irq 0/2. -- error compiling committee.c: too many arguments to function