From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755279AbdKJGd1 (ORCPT ); Fri, 10 Nov 2017 01:33:27 -0500 Received: from mail-pg0-f66.google.com ([74.125.83.66]:55581 "EHLO mail-pg0-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751113AbdKJGdZ (ORCPT ); Fri, 10 Nov 2017 01:33:25 -0500 X-Google-Smtp-Source: ABhQp+QFNHoUHBpzroa5b3ASOZ+wULIIgWD0gAWkRRc75gzMAnH9LbDH3S2CQ28CV+Iq/hpfxxIhyA== Date: Fri, 10 Nov 2017 15:30:53 +0900 From: Namhyung Kim To: Mengting Zhang Cc: jolsa@redhat.com, alexander.shishkin@linux.intel.com, acme@kernel.org, Linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org, huawei.libin@huawei.com, wangnan0@huawei.com, kernel-team@lge.com Subject: Re: [PATCH] perf evsel: Fix incorrect precise_ip in default event name Message-ID: <20171110063053.GA1544@danjae.aot.lge.com> References: <1510292946-23686-1-git-send-email-zhangmengting@huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <1510292946-23686-1-git-send-email-zhangmengting@huawei.com> User-Agent: Mutt/1.9.1 (2017-09-22) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello, On Fri, Nov 10, 2017 at 01:49:06PM +0800, Mengting Zhang wrote: > When no event is specified with -e option, perf will specify a > "cycles" event with the highest level of precision available in > perf_event_attr.precise_ip as the default event. But the evsel name > shows an incorrect precise ip, fix it. > > For example, with a highest precision perf_event_attr.precise_ip = 2, > the evsel name "cycles:ppp" shows a wrong precision available. > > Before: > $./perf record sleep 1 > [ perf record: Woken up 1 times to write data ] > [ perf record: Captured and wrote 0.014 MB perf.data (21 samples) ] > $./perf evlist -v > cycles:ppp: size: 112, { sample_period, sample_freq }: 4000, > sample_type: IP|TID|TIME|PERIOD, disabled: 1, inherit: 1, mmap: 1, > comm: 1, freq: 1, enable_on_exec: 1, task: 1, precise_ip: 2, > sample_id_all: 1, exclude_guest: 1, mmap2: 1, comm_exec: 1 > > After: > $./perf record sleep 1 > [ perf record: Woken up 1 times to write data ] > [ perf record: Captured and wrote 0.014 MB perf.data (16 samples) ] > $./perf evlist -v > cycles:pp: size: 112, { sample_period, sample_freq }: 4000, > sample_type: IP|TID|TIME|PERIOD, disabled: 1, inherit: 1, mmap: 1, > comm: 1, freq: 1, enable_on_exec: 1, task: 1, precise_ip: 2, > sample_id_all: 1, exclude_guest: 1, mmap2: 1, comm_exec: 1 > > Signed-off-by: Mengting Zhang > --- > tools/perf/util/evsel.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c > index 0dccdb8..94cf11d 100644 > --- a/tools/perf/util/evsel.c > +++ b/tools/perf/util/evsel.c > @@ -312,7 +312,7 @@ struct perf_evsel *perf_evsel__new_cycles(bool precise) > if (asprintf(&evsel->name, "cycles%s%s%.*s", > (attr.precise_ip || attr.exclude_kernel) ? ":" : "", > attr.exclude_kernel ? "u" : "", > - attr.precise_ip ? attr.precise_ip + 1 : 0, "ppp") < 0) > + attr.precise_ip ? attr.precise_ip : 0, "ppp") < 0) I think you don't need to check value of the precise_ip anymore. The following should be ok: attr.precise_ip, "ppp") < 0) Thanks, Namhyung