From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752241Ab3IFMxQ (ORCPT ); Fri, 6 Sep 2013 08:53:16 -0400 Received: from mail-vc0-f171.google.com ([209.85.220.171]:58747 "EHLO mail-vc0-f171.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751432Ab3IFMxP (ORCPT ); Fri, 6 Sep 2013 08:53:15 -0400 Date: Fri, 6 Sep 2013 09:53:04 -0300 From: Arnaldo Carvalho de Melo To: Adrian Hunter Cc: Peter Zijlstra , linux-kernel@vger.kernel.org, David Ahern , Frederic Weisbecker , Jiri Olsa , Mike Galbraith , Namhyung Kim , Paul Mackerras , Stephane Eranian Subject: Re: [PATCH] perf kvm: fix sample_type manipulation Message-ID: <20130906125304.GA29064@ghostprotocols.net> References: <1378450134-28982-1-git-send-email-adrian.hunter@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1378450134-28982-1-git-send-email-adrian.hunter@intel.com> X-Url: http://acmel.wordpress.com User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Em Fri, Sep 06, 2013 at 09:48:54AM +0300, Adrian Hunter escreveu: > Manipulating the sample_type of an evsel requires > the use of: > perf_evsel__set_sample_bit() > and perf_evsel__reset_sample_bit() Fine, but... > Manipulating the sample type of an evlist requires > the id position to be recalculated. ... can't we hide this detail? I.e. we could do it like we do with the alloc_{mmap,poll}() evlist methods in perf_evlist__mmap(), checking if it was already done, etc. This we reduce the contact surface for tools using evlists and evsels. I.e., this sequence: + perf_evlist__set_id_pos(evlist); + err = perf_evlist__open(evlist); Could remain just: err = perf_evlist__open(evlist); I'm auditing the other calls to evlist now, to check if there are other cases. Thanks for the patch! - Arnaldo > Signed-off-by: Adrian Hunter > --- > tools/perf/builtin-kvm.c | 20 +++++++++++--------- > 1 file changed, 11 insertions(+), 9 deletions(-) > > diff --git a/tools/perf/builtin-kvm.c b/tools/perf/builtin-kvm.c > index 47b3540..0b7c5a9 100644 > --- a/tools/perf/builtin-kvm.c > +++ b/tools/perf/builtin-kvm.c > @@ -1165,16 +1165,16 @@ static int kvm_live_open_events(struct perf_kvm_stat *kvm) > struct perf_event_attr *attr = &pos->attr; > > /* make sure these *are* set */ > - attr->sample_type |= PERF_SAMPLE_TID; > - attr->sample_type |= PERF_SAMPLE_TIME; > - attr->sample_type |= PERF_SAMPLE_CPU; > - attr->sample_type |= PERF_SAMPLE_RAW; > + perf_evsel__set_sample_bit(pos, TID); > + perf_evsel__set_sample_bit(pos, TIME); > + perf_evsel__set_sample_bit(pos, CPU); > + perf_evsel__set_sample_bit(pos, RAW); > /* make sure these are *not*; want as small a sample as possible */ > - attr->sample_type &= ~PERF_SAMPLE_PERIOD; > - attr->sample_type &= ~PERF_SAMPLE_IP; > - attr->sample_type &= ~PERF_SAMPLE_CALLCHAIN; > - attr->sample_type &= ~PERF_SAMPLE_ADDR; > - attr->sample_type &= ~PERF_SAMPLE_READ; > + perf_evsel__reset_sample_bit(pos, PERIOD); > + perf_evsel__reset_sample_bit(pos, IP); > + perf_evsel__reset_sample_bit(pos, CALLCHAIN); > + perf_evsel__reset_sample_bit(pos, ADDR); > + perf_evsel__reset_sample_bit(pos, READ); > attr->mmap = 0; > attr->comm = 0; > attr->task = 0; > @@ -1188,6 +1188,8 @@ static int kvm_live_open_events(struct perf_kvm_stat *kvm) > attr->disabled = 1; > } > > + perf_evlist__set_id_pos(evlist); > + > err = perf_evlist__open(evlist); > if (err < 0) { > printf("Couldn't create the events: %s\n", strerror(errno)); > -- > 1.7.11.7