[PATCH v1 6/6] perf cs-etm: Generate branch sample for CS_ETM_TRACE_ON packet
From: Leo Yan <hidden>
Date: 2018-06-18 05:11:11
Also in:
lkml
Subsystem:
arm/coresight framework and drivers, performance events subsystem, performance events tooling arm64, the rest · Maintainers:
Suzuki K Poulose, Peter Zijlstra, Ingo Molnar, Arnaldo Carvalho de Melo, Namhyung Kim, Linus Torvalds
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 <redacted> --- 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 d3b7942..2ae6402 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) {
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2.7.4