From: James Clark <james.clark@arm.com>
To: Yang Shi <shy828301@gmail.com>
Cc: linux-perf-users@vger.kernel.org,
LAK <linux-arm-kernel@lists.infradead.org>,
coresight@lists.linaro.org,
Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
leo.yan@linaro.org, mathieu.poirier@linaro.org,
adrian.hunter@intel.com, Jiri Olsa <jolsa@kernel.org>,
acme@redhat.com, mike.leach@linaro.org,
Will Deacon <will@kernel.org>,
suzuki.poulose@arm.com
Subject: Re: [BUG] perf: No samples found when using kcore + coresight
Date: Tue, 7 Mar 2023 10:32:33 +0000 [thread overview]
Message-ID: <8ca2b07e-674e-afb6-ff12-87504f51f252@arm.com> (raw)
In-Reply-To: <CAHbLzkrJQTrYBtPkf=jf3OpQ-yBcJe7XkvQstX9j2frz4WF-SQ@mail.gmail.com>
On 06/03/2023 21:13, Yang Shi wrote:
> Hi,
>
> I'm seeking some help regarding perf record --kcore + coresight. When
> I tracing with perf record --kcore -e cs_etm ... , perf report shows
> "The perf.data/data data has no samples!".
>
> I tried other combinations:
> 1. perf record --kcore (w/o using coresight): works
> 2. perf record -e cs_etm ... : works
> 3. Manually copy kcore with perf buildid-cache, then run perf record
> -e cs_etm... : works
>
> So just "perf record --kcore -e cs_etm ..." doesn't work.
>
> I'm using v6.2 kernel and the perf is built from the same kernel
> source with OpenCSD 1.4. Also attached the sample file generated by
> perf.
>
> Any suggestion is appreciated.
>
> Thanks,
> Yang
Hi Yang,
I don't see any issue with this command and I still get samples:
perf record -e cs_etm// --kcore -- true
You might want to try running both record and report in verbose and
stdio mode (-vvv --stdio) to see if you see any warnings.
I can't think of any way --kcore would cause an issue because all it
does is save kcore into the .debug cache rather than affecting the
actual perf.data file.
Are you running perf report in the same place the recording was made? Or
on another system?
James
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
next parent reply other threads:[~2023-03-07 10:33 UTC|newest]
Thread overview: 16+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <CAHbLzkrJQTrYBtPkf=jf3OpQ-yBcJe7XkvQstX9j2frz4WF-SQ@mail.gmail.com>
2023-03-07 10:32 ` James Clark [this message]
2023-03-07 19:45 ` [BUG] perf: No samples found when using kcore + coresight Yang Shi
2023-03-08 19:56 ` Yang Shi
2023-03-09 11:38 ` Leo Yan
[not found] ` <CAHbLzkpvLHnyL5J5kB_ke3CWVq2=MOEdEQsGex56+Esfgqh1=g@mail.gmail.com>
2023-03-13 12:14 ` Leo Yan
2023-03-13 18:15 ` Yang Shi
2023-03-14 0:36 ` Leo Yan
2023-03-28 0:53 ` Yang Shi
2023-03-28 8:59 ` James Clark
2023-03-28 16:16 ` Yang Shi
2023-03-29 16:08 ` James Clark
2023-03-29 23:25 ` Yang Shi
2023-03-30 8:17 ` James Clark
2023-03-29 16:11 ` James Clark
2023-03-30 10:36 ` James Clark
2023-03-30 19:54 ` Yang Shi
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=8ca2b07e-674e-afb6-ff12-87504f51f252@arm.com \
--to=james.clark@arm.com \
--cc=acme@redhat.com \
--cc=adrian.hunter@intel.com \
--cc=coresight@lists.linaro.org \
--cc=jolsa@kernel.org \
--cc=leo.yan@linaro.org \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-perf-users@vger.kernel.org \
--cc=mathieu.poirier@linaro.org \
--cc=mike.leach@linaro.org \
--cc=shy828301@gmail.com \
--cc=suzuki.poulose@arm.com \
--cc=will@kernel.org \
/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