[PATCH v3 2/4] perf arm-spe: Update --switch-events docs in perf-record

German Gomez german.gomez at arm.com
Thu Nov 11 05:36:23 PST 2021


Update perf-record docs and Arm SPE recording options so that they are
consistent. This includes supporting the --no-switch-events flag in Arm
SPE as well.

Signed-off-by: German Gomez <german.gomez at arm.com>
Acked-by: Namhyung Kim <namhyung at kernel.org>
Reviewed-by: Leo Yan <leo.yan at linaro.org>
---
 tools/perf/Documentation/perf-record.txt | 2 +-
 tools/perf/arch/arm64/util/arm-spe.c     | 4 +++-
 2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/tools/perf/Documentation/perf-record.txt b/tools/perf/Documentation/perf-record.txt
index 2d7df8703..3cf7bac67 100644
--- a/tools/perf/Documentation/perf-record.txt
+++ b/tools/perf/Documentation/perf-record.txt
@@ -469,7 +469,7 @@ This option sets the time out limit. The default value is 500 ms.
 
 --switch-events::
 Record context switch events i.e. events of type PERF_RECORD_SWITCH or
-PERF_RECORD_SWITCH_CPU_WIDE. In some cases (e.g. Intel PT or CoreSight)
+PERF_RECORD_SWITCH_CPU_WIDE. In some cases (e.g. Intel PT, CoreSight or Arm SPE)
 switch events will be enabled automatically, which can be suppressed by
 by the option --no-switch-events.
 
diff --git a/tools/perf/arch/arm64/util/arm-spe.c b/tools/perf/arch/arm64/util/arm-spe.c
index 58ba8d15c..725a06cd2 100644
--- a/tools/perf/arch/arm64/util/arm-spe.c
+++ b/tools/perf/arch/arm64/util/arm-spe.c
@@ -169,8 +169,10 @@ static int arm_spe_recording_options(struct auxtrace_record *itr,
 	if (!perf_cpu_map__empty(cpus)) {
 		evsel__set_sample_bit(tracking_evsel, TIME);
 		evsel__set_sample_bit(tracking_evsel, CPU);
+
 		/* also track task context switch */
-		tracking_evsel->core.attr.context_switch = 1;
+		if (!record_opts__no_switch_events(opts))
+			tracking_evsel->core.attr.context_switch = 1;
 	}
 
 	return 0;
-- 
2.25.1




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