[PATCH 02/14] perf cs-etm: Warn for invalid timestamp option
From: James Clark <james.clark@linaro.org>
Date: 2026-08-11 15:31:05
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Subsystem:
arm/coresight framework and drivers, performance events subsystem, the rest · Maintainers:
Suzuki K Poulose, Peter Zijlstra, Ingo Molnar, Arnaldo Carvalho de Melo, Namhyung Kim, Linus Torvalds
Instead of silently returning an error, print a useful warning. Signed-off-by: James Clark <james.clark@linaro.org> --- tools/perf/arch/arm/util/cs-etm.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/tools/perf/arch/arm/util/cs-etm.c b/tools/perf/arch/arm/util/cs-etm.c
index d2861d66a661..acfdb3f53821 100644
--- a/tools/perf/arch/arm/util/cs-etm.c
+++ b/tools/perf/arch/arm/util/cs-etm.c@@ -176,8 +176,11 @@ static int cs_etm_validate_timestamp(struct perf_pmu *cs_etm_pmu, struct evsel * * 0b01000 Implementation supports a maximum timestamp of 64bits. */ trcidr0 &= GENMASK(28, 24); - if (!trcidr0) + if (!trcidr0) { + pr_err("%s: timestamp not supported by HW, disable with %s/timestamp=0/\n", + CORESIGHT_ETM_PMU_NAME, CORESIGHT_ETM_PMU_NAME); return -EINVAL; + } return 0; }
--
2.43.0