Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753042Ab3HEPAr (ORCPT ); Mon, 5 Aug 2013 11:00:47 -0400 Received: from mail-pd0-f172.google.com ([209.85.192.172]:63158 "EHLO mail-pd0-f172.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752485Ab3HEPAq (ORCPT ); Mon, 5 Aug 2013 11:00:46 -0400 Message-ID: <51FFBE17.60409@gmail.com> Date: Mon, 05 Aug 2013 11:00:39 -0400 From: David Ahern User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.8; rv:17.0) Gecko/20130620 Thunderbird/17.0.7 MIME-Version: 1.0 To: Xiao Guangrong CC: acme@ghostprotocols.net, linux-kernel@vger.kernel.org, Ingo Molnar , Frederic Weisbecker , Peter Zijlstra , Jiri Olsa , Namhyung Kim , Runzhen Wang Subject: Re: [PATCH 8/9] perf kvm: debug for missing vmexit/vmentry event References: <1375473947-64285-1-git-send-email-dsahern@gmail.com> <1375473947-64285-9-git-send-email-dsahern@gmail.com> <51FF4BEA.7070308@linux.vnet.ibm.com> In-Reply-To: <51FF4BEA.7070308@linux.vnet.ibm.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2357 Lines: 67 On 8/5/13 2:53 AM, Xiao Guangrong wrote: > On 08/03/2013 04:05 AM, David Ahern wrote: >> Expected to have missing events for each vcpu when perf is >> started. After that should not have missing events. > > Sorry, i can not understand what's this info used for. For debugging. Things that should not happen do seem to happen -- rarely, but it does > >> >> Signed-off-by: David Ahern >> Cc: Arnaldo Carvalho de Melo >> Cc: Ingo Molnar >> Cc: Frederic Weisbecker >> Cc: Peter Zijlstra >> Cc: Jiri Olsa >> Cc: Namhyung Kim >> Cc: Xiao Guangrong >> Cc: Runzhen Wang >> --- >> tools/perf/builtin-kvm.c | 15 +++++++++++++-- >> 1 file changed, 13 insertions(+), 2 deletions(-) >> >> diff --git a/tools/perf/builtin-kvm.c b/tools/perf/builtin-kvm.c >> index 28afc05d..41dd25a 100644 >> --- a/tools/perf/builtin-kvm.c >> +++ b/tools/perf/builtin-kvm.c >> @@ -568,11 +568,22 @@ static bool handle_kvm_event(struct perf_kvm_stat *kvm, >> (kvm->trace_vcpu != vcpu_record->vcpu_id)) >> return true; >> >> - if (kvm->events_ops->is_begin_event(evsel, sample, &key)) >> + if (kvm->events_ops->is_begin_event(evsel, sample, &key)) { >> + if (vcpu_record->start_time) { >> + pr_debug("consecutive begin events (%s) for pid %d, vcpu %d\n", >> + evsel->name, sample->pid, vcpu_record->vcpu_id); >> + } > > This is not true, the ->start_time is set in handle_begin_event() for the new alloced > vcpu_record. > > If you just want to know the point where is the first event lost, you can track > it in: > > static bool handle_end_event(struct perf_kvm_stat *kvm, > struct vcpu_event_record *vcpu_record, > struct event_key *key, > u64 timestamp) > { > ...... > > /* The begin event is not caught. */ > if (!time_begin) <====== > return true; > Ok. I'll drop the patch. I added it for a reason, but can't remember why at the moment. David -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/