Re: [PATCH v2 08/18] perf test cs-etm: Replace memcpy test with raw dump stress test

On Tue, Jun 02, 2026 at 03:26:50PM +0100, James Clark wrote:

[...]

+# Use exit snapshot to record 2M of trace to make about 80MB of raw dump data. +echo "Recording..." +perf record -e cs_etm/timestamp=0/u -m,2M -Se -o "$tmpdir/data" -- \

• perf test -w brstack 20000 > /dev/null 2>&1

...

+size=$(stat -c%s "$tmpdir/rawdump") +if [ $size -gt $((50 * 1024 * 1024)) ]; then

• echo "PASS: Raw dump file is larger than 50MB"
• cleanup
• exit 0

+fi

I am not sure how we can map 2MiB trace data to 50MiB+ raw dump. This is not to verify perf stuffs but just expect how verbose output from decoder.

Can we simply verify the trace data is ~2MiB with the command:

perf report -D | grep ". ... CoreSight .* Trace data: size .* bytes"

We might relax the check as the trace size >= 90% * 2MiB

Thanks, Leo