linux-perf-users.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Mengting Zhang <zhangmengting@huawei.com>
To: jolsa@redhat.com, namhyung@kernel.org,
	alexander.shishkin@linux.intel.com
Cc: acme@kernel.org, Linux-kernel@vger.kernel.org,
	linux-perf-users@vger.kernel.org, huawei.libin@huawei.com,
	wangnan0@huawei.com, zhangmengting@huawei.com
Subject: [PATCH v2] perf evsel: Fix incorrect precise_ip in default event name
Date: Fri, 10 Nov 2017 15:57:08 +0800	[thread overview]
Message-ID: <1510300628-31648-1-git-send-email-zhangmengting@huawei.com> (raw)

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 <zhangmengting@huawei.com>
---
 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..d6a6205 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, "ppp") < 0)
 		goto error_free;
 out:
 	return evsel;
-- 
1.7.12.4

                 reply	other threads:[~2017-11-10  8:06 UTC|newest]

Thread overview: [no followups] expand[flat|nested]  mbox.gz  Atom feed

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=1510300628-31648-1-git-send-email-zhangmengting@huawei.com \
    --to=zhangmengting@huawei.com \
    --cc=Linux-kernel@vger.kernel.org \
    --cc=acme@kernel.org \
    --cc=alexander.shishkin@linux.intel.com \
    --cc=huawei.libin@huawei.com \
    --cc=jolsa@redhat.com \
    --cc=linux-perf-users@vger.kernel.org \
    --cc=namhyung@kernel.org \
    --cc=wangnan0@huawei.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).