[PATCH v3 2/3] perf cs-etm: Start reading 'Z' --itrace option

James Clark james.clark at arm.com
Mon May 17 06:17:40 PDT 2021


Recently the 'Z' --itrace option was added to override detection
of timeless decoding. This is also useful in Coresight to work around
issues with invalid timestamps on some hardware.

When the 'Z' option is provided, the existing timeless decoding mode
will be used, even if timestamps were recorded.

Reviewed-by: Leo Yan <leo.yan at linaro.org>
Signed-off-by: James Clark <james.clark at arm.com>
---
 tools/perf/util/cs-etm.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/tools/perf/util/cs-etm.c b/tools/perf/util/cs-etm.c
index a752fe06f170..64536a6ed10a 100644
--- a/tools/perf/util/cs-etm.c
+++ b/tools/perf/util/cs-etm.c
@@ -2473,6 +2473,10 @@ static bool cs_etm__is_timeless_decoding(struct cs_etm_auxtrace *etm)
 	struct evlist *evlist = etm->session->evlist;
 	bool timeless_decoding = true;
 
+	/* Override timeless mode with user input from --itrace=Z */
+	if (etm->synth_opts.timeless_decoding)
+		return true;
+
 	/*
 	 * Circle through the list of event and complain if we find one
 	 * with the time bit set.
-- 
2.28.0




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