From mboxrd@z Thu Jan 1 00:00:00 1970 From: Paolo Bonzini Subject: Re: [PATCH 1/2] KVM: x86: set TMR when the interrupt is accepted Date: Tue, 4 Aug 2015 08:59:56 +0200 Message-ID: <55C062EC.20006@redhat.com> References: <1438177055-26764-1-git-send-email-pbonzini@redhat.com> <1438177055-26764-2-git-send-email-pbonzini@redhat.com> <55BB2B62.1030605@redhat.com> <55BF21E1.5030100@redhat.com> <55BF48A4.5030409@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Cc: "alex.williamson@redhat.com" , "srutherford@intel.com" , "Gudimetla, Giridhar Kumar" To: "Zhang, Yang Z" , "linux-kernel@vger.kernel.org" , "kvm@vger.kernel.org" Return-path: Received: from mail-wi0-f182.google.com ([209.85.212.182]:34947 "EHLO mail-wi0-f182.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751453AbbHDG76 (ORCPT ); Tue, 4 Aug 2015 02:59:58 -0400 In-Reply-To: Sender: kvm-owner@vger.kernel.org List-ID: On 04/08/2015 02:46, Zhang, Yang Z wrote: > > It is a problem for split irqchip, where the EOI exit bitmap can be > > inferred from the IOAPIC routes but the TMR cannot. The hardware > > behavior on the other hand can be implemented purely within the LAPIC. > > So updating the TMR within LAPIC is the only solution to handle it? It's the simplest and the one that makes most sense. Considering that TMR is a pretty obscure feature, it's unlikely that it will be accelerated in the future. Paolo