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

[Leo Yan]

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