From mboxrd@z Thu Jan 1 00:00:00 1970 From: Avi Kivity Subject: Re: [RFC] para virt interface of perf to support kvm guest os statistics collection in guest os Date: Wed, 09 Jun 2010 14:12:47 +0300 Message-ID: <4C0F772F.6090206@redhat.com> References: <1276054214.2096.383.camel@ymzhang.sh.intel.com> <4C0F51DD.3080200@redhat.com> <1276075280.2096.427.camel@ymzhang.sh.intel.com> <4C0F61D3.9000402@redhat.com> <1276078122.2046.1227.camel@twins> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Cc: "Zhang, Yanmin" , LKML , kvm@vger.kernel.org, Ingo Molnar , Fr??d??ric Weisbecker , Arnaldo Carvalho de Melo , Cyrill Gorcunov , Lin Ming , Sheng Yang , Marcelo Tosatti , oerg Roedel , Jes Sorensen , Gleb Natapov , Zachary Amsden , zhiteng.huang@intel.com, tim.c.chen@intel.com To: Peter Zijlstra Return-path: In-Reply-To: <1276078122.2046.1227.camel@twins> Sender: linux-kernel-owner@vger.kernel.org List-Id: kvm.vger.kernel.org On 06/09/2010 01:08 PM, Peter Zijlstra wrote: > On Wed, 2010-06-09 at 12:41 +0300, Avi Kivity wrote: > >> >>>> Disabling the watchdog is unfortunate. Why is it necessary? >>>> >>>> >>> perf always uses NMI, so we disable the nmi_watchdog when a perf_event is >>> set up in case they might have impact. >>> >>> >> Ok. Is that the case for the hardware pmus as well? If so it might be >> done in common code. >> > The x86 hardware pmu implementation disables the lapic watchdog too, but > recent kernels come with a watchdog implementation on top of perf, the > old lapic one will be depricated. > So this should indeed be in common code, and removed (for all pmus) when the new watchdog is merged in 2.6.36. -- error compiling committee.c: too many arguments to function