[PATCH v3 5/5] perf test: arm_spe: Add test for discard mode

[James Clark <james.clark@linaro.org>]

Add a test that checks that there were no AUX or AUXTRACE events
recorded when discard mode is used.

Reviewed-by: Yeoreum Yun <yeoreum.yun@arm.com>
Signed-off-by: James Clark <james.clark@linaro.org>
---
 tools/perf/tests/shell/test_arm_spe.sh | 30 ++++++++++++++++++++++++++
 1 file changed, 30 insertions(+)

diff --git a/tools/perf/tests/shell/test_arm_spe.sh b/tools/perf/tests/shell/test_arm_spe.sh
index 3258368634f7..a69aab70dd8a 100755
--- a/tools/perf/tests/shell/test_arm_spe.sh
+++ b/tools/perf/tests/shell/test_arm_spe.sh
@@ -107,7 +107,37 @@ arm_spe_system_wide_test() {
 	arm_spe_report "SPE system-wide testing" $err
 }
 
+arm_spe_discard_test() {
+	echo "SPE discard mode"
+
+	for f in /sys/bus/event_source/devices/arm_spe_*; do
+		if [ -e "$f/format/discard" ]; then
+			cpu=$(cut -c -1 "$f/cpumask")
+			break
+		fi
+	done
+
+	if [ -z $cpu ]; then
+		arm_spe_report "SPE discard mode not present" 2
+		return
+	fi
+
+	# Test can use wildcard SPE instance and Perf will only open the event
+	# on instances that have that format flag. But make sure the target
+	# runs on an instance with discard mode otherwise we're not testing
+	# anything.
+	perf record -o ${perfdata} -e arm_spe/discard/ -N -B --no-bpf-event \
+		-- taskset --cpu-list $cpu true
+
+	if perf report -i ${perfdata} --stats | grep 'AUX events\|AUXTRACE events'; then
+		arm_spe_report "SPE discard mode found unexpected data" 1
+	else
+		arm_spe_report "SPE discard mode" 0
+	fi
+}
+
 arm_spe_snapshot_test
 arm_spe_system_wide_test
+arm_spe_discard_test
 
 exit $glb_err
-- 
2.34.1