[BUG] perf: No samples found when using kcore + coresight

From: Yang Shi
Date: Mon Mar 06 2023 - 16:13:49 EST


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

Attachment: perf.data.broken
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