From mboxrd@z Thu Jan 1 00:00:00 1970 From: Marcelo Tosatti Subject: Re: [PATCH 03/15] kvm: Install optimized interrupt handlers Date: Sat, 5 Mar 2011 23:13:03 -0300 Message-ID: <20110306021303.GA12222@amt.cnet> References: <29e857949ee4ff738c7c2f27063ee945a1af4875.1299233998.git.jan.kiszka@siemens.com> <20110305153759.GA2692@amt.cnet> <4D727CE9.8010107@web.de> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Avi Kivity , kvm@vger.kernel.org, qemu-devel@nongnu.org To: Jan Kiszka Return-path: Received: from mx1.redhat.com ([209.132.183.28]:18109 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753266Ab1CGAgm (ORCPT ); Sun, 6 Mar 2011 19:36:42 -0500 Content-Disposition: inline In-Reply-To: <4D727CE9.8010107@web.de> Sender: kvm-owner@vger.kernel.org List-ID: On Sat, Mar 05, 2011 at 07:11:53PM +0100, Jan Kiszka wrote: > On 2011-03-05 16:37, Marcelo Tosatti wrote: > > On Fri, Mar 04, 2011 at 11:20:00AM +0100, Jan Kiszka wrote: > >> KVM only requires to set the raised IRQ in CPUState and, if the user > >> space irqchip is used, to kick the receiving vcpu if it is remote. > >> > >> Signed-off-by: Jan Kiszka > >> --- > >> kvm-all.c | 17 +++++++++++++++++ > >> 1 files changed, 17 insertions(+), 0 deletions(-) > >> > >> diff --git a/kvm-all.c b/kvm-all.c > >> index 226843c..c460d45 100644 > >> --- a/kvm-all.c > >> +++ b/kvm-all.c > >> @@ -650,6 +650,20 @@ static CPUPhysMemoryClient kvm_cpu_phys_memory_client = { > >> .log_stop = kvm_log_stop, > >> }; > >> > >> +static void kvm_handle_interrupt(CPUState *env, int mask) > >> +{ > >> + env->interrupt_request |= mask; > >> + > > > > If the env->interrupt_request request is processed in userspace, such as > > MCE, the kick is still necessary for irqchip case. CPU_INTERRUPT_DEBUG > > is another example, no? > > [this probably targeted kvm_handle_interrupt_kernel_irqchip] > > In principle, you are right. But MCE must be injected synchronously over > the target VCPU, see do_inject_x86_mce, and CPU_INTERRUPT_DEBUG is also > synchronous and not even used in KVM mode. CPU_INTERRUPT_NMI from monitor? Don't see what gain you expect from avoiding the signal in this case.