CS_ETM_TRACE_ON packet itself can give the info that there have a discontinuity in the trace, this patch is to add branch sample for CS_ETM_TRACE_ON packet if it is inserted in the middle of CS_ETM_RANGE packets; as result we can have hint for the trace discontinuity.
Signed-off-by: Leo Yan leo.yan@linaro.org --- tools/perf/util/cs-etm.c | 24 +++++++++++++++++------- 1 file changed, 17 insertions(+), 7 deletions(-)
diff --git a/tools/perf/util/cs-etm.c b/tools/perf/util/cs-etm.c index beff486..6815f5b 100644 --- a/tools/perf/util/cs-etm.c +++ b/tools/perf/util/cs-etm.c @@ -910,13 +910,23 @@ static int cs_etm__sample(struct cs_etm_queue *etmq) etmq->period_instructions = instrs_over; }
- if (etm->sample_branches && - etmq->prev_packet && - etmq->prev_packet->sample_type == CS_ETM_RANGE && - etmq->prev_packet->last_instr_taken_branch) { - ret = cs_etm__synth_branch_sample(etmq); - if (ret) - return ret; + if (etm->sample_branches && etmq->prev_packet) { + bool generate_sample = false; + + /* Generate sample for tracing on packet */ + if (etmq->prev_packet->sample_type == CS_ETM_TRACE_ON) + generate_sample = true; + + /* Generate sample for branch taken packet */ + if (etmq->prev_packet->sample_type == CS_ETM_RANGE && + etmq->prev_packet->last_instr_taken_branch) + generate_sample = true; + + if (generate_sample) { + ret = cs_etm__synth_branch_sample(etmq); + if (ret) + return ret; + } }
if (etm->sample_branches || etm->synth_opts.last_branch) {