From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751196Ab2AQC2U (ORCPT ); Mon, 16 Jan 2012 21:28:20 -0500 Received: from e28smtp06.in.ibm.com ([122.248.162.6]:46881 "EHLO e28smtp06.in.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750715Ab2AQC2S (ORCPT ); Mon, 16 Jan 2012 21:28:18 -0500 Message-ID: <4F14DCBB.3060207@linux.vnet.ibm.com> Date: Tue, 17 Jan 2012 10:28:11 +0800 From: Xiao Guangrong User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:9.0) Gecko/20111222 Thunderbird/9.0 MIME-Version: 1.0 To: Avi Kivity CC: Marcelo Tosatti , LKML , KVM Subject: Re: [PATCH 2/3] KVM: improve trace events of vmexit/mmio/ioport References: <4F13EE3D.2070602@linux.vnet.ibm.com> <4F13EE9B.9020901@linux.vnet.ibm.com> <4F13EFFB.90706@redhat.com> In-Reply-To: <4F13EFFB.90706@redhat.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit x-cbid: 12011702-9574-0000-0000-000000F8C97D Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 01/16/2012 05:38 PM, Avi Kivity wrote: > On 01/16/2012 11:32 AM, Xiao Guangrong wrote: >> - trace vcpu_id for these events > > We can infer the vcpu id from the kvm_entry tracepoints, no? > Thanks for your review, Avi! Hmm. i think it is hard to do since the vcpu thread can be scheduled anytime, one example is as follow: CPU 0 kvm_entry vcpu 0 ...... kvm_entry vcpu 1 ...... event1 occurs ...... event2 occurs It is hard to know the event belong to which kvm_entry? >> - add kvm_mmio_done to trace the time when mmio/ioport emulation is completed > > ditto? > I think is ok to get the event end time by using kvm_entry. > > Relying on the existing tracepoints will make the tool work on older > kernels. > We can drop all new events, but unfortunately, the information of the origin tracepoints is not enough, at least vcpu_id need be traced in theses events to match its events. Yes?