Good day Bharat,
Please make sure to CC the coresight mailing list (as Mike did) when you have questions about the sub-system. There are plenty of qualified people on the list that can answer questions and because of timezones, they usually do so much faster than I can.
Thanks, Mathieu
On Mon, 21 Oct 2019 at 09:31, Mike Leach mike.leach@linaro.org wrote:
Hi,
From the little information in this mail, this looks like an issue with how the version of perf you have is interacting with the OpenCSD library. An ocsdError will usually be generated if the library detects input errors in configuration or data being passed to it.
ocsdErrors in general should provide a code + string - though output could be being suppressed by perf. I would follow Leo's suggestion to see if you can spot the library call from the backtrace that causes the issue.
Regards
Mike
On Mon, 21 Oct 2019 at 06:39, Leo Yan leo.yan@linaro.org wrote:
Hi Bharat,
[ + Mike ]
On Mon, Oct 21, 2019 at 05:28:54AM +0000, Bharat Bhushan wrote:
Hi Leo, Mathieu,
I found your email-id from linux git-log, Please ignore if you are not right person.
I am using perf for hwtracing (coresight).
$perf record -C 0 -e cs_etm/@tmc_etr0/u ./test Couldn't synthesize bpf events. [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.124 MB perf.data ] $ perf report terminate called after throwing an instance of 'ocsdError' terminate called recursively Aborted (core dumped) $ perf report -v build id event received for [kernel.kallsyms]: 473d5d96eceb209a58f19ec8f3e4f74891d49c9f build id event received for /usr/lib/systemd/systemd: 16460ffcbc368221e1e71c587c059a44497eb3de build id event received for /usr/lib/aarch64-linux-gnu/libudev.so.1.6.12: bf0152a1c65039afe462800eb834190830a5c8d2 . <snip> . build id event received for /usr/lib/aarch64-linux-gnu/libdw-0.176.so: ad9dc3a40b2f39629fcc70ad2bb931d75f89b748 build id event received for /usr/lib/aarch64-linux-gnu/libelf-0.176.so: 0b36ddcd158758dcb8356713eff8fe12c1326d21 build id event received for /usr/lib/libopencsd_c_api.so.0.12.0: 84a1cf9a8b6efb9670b902d87118f05c81856b53 Aborted (core dumped) terminate called after throwing an instance of 'ocsdError' terminate called recursively root@ubuntu:~# Also I added prints in "perf" source code before calling and opencsd library function (please find attached file) and no prints observed. I am not sure why we are getting "ocsdError". Can you please point what's wrong I am doing.I think the error is reported internally in OpenCSD rather than the failure in perf tool.
And you could see there have core dump file, suggest you could to use the core dump file with gdb to dump the backtrace. Then this can help us to find the flow for the failure.
I loop Mike since this issue is more likely related with decoder.
Thanks, Leo Yan
-- Mike Leach Principal Engineer, ARM Ltd. Manchester Design Centre. UK