From: Adrian Hunter <adrian.hunter@xxxxxxxxx> commit 430635a0ef1ce958b7b4311f172694ece2c692b8 upstream. After a standalone CBR (not associated with TSC), update the cycles reference timestamp and reset the cycle count, so that CYC timestamps are calculated relative to that point with the new frequency. Fixes: cc33618619cefc6d ("perf tools: Add Intel PT support for decoding CYC packets") Signed-off-by: Adrian Hunter <adrian.hunter@xxxxxxxxx> Cc: Adrian Hunter <adrian.hunter@xxxxxxxxx> Cc: Ian Rogers <irogers@xxxxxxxxxx> Cc: Jiri Olsa <jolsa@xxxxxxxxxx> Cc: Namhyung Kim <namhyung@xxxxxxxxxx> Cc: stable@xxxxxxxxxxxxxxx Link: https://lore.kernel.org/r/20230403154831.8651-2-adrian.hunter@xxxxxxxxx Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- tools/perf/util/intel-pt-decoder/intel-pt-decoder.c | 2 ++ 1 file changed, 2 insertions(+) --- a/tools/perf/util/intel-pt-decoder/intel-pt-decoder.c +++ b/tools/perf/util/intel-pt-decoder/intel-pt-decoder.c @@ -1998,6 +1998,8 @@ static void intel_pt_calc_cbr(struct int decoder->cbr = cbr; decoder->cbr_cyc_to_tsc = decoder->max_non_turbo_ratio_fp / cbr; + decoder->cyc_ref_timestamp = decoder->timestamp; + decoder->cycle_cnt = 0; intel_pt_mtc_cyc_cnt_cbr(decoder); }