perf test: Reset shadow counts before loading

Otherwise load counting is an average. Without this change
duration_time in test_memory_bandwidth will alter its value if an
earlier test contains duration_time.

This patch fixes an issue that's introduced in the proposed patch:
in perf test "Parse and process metrics".

Signed-off-by: Ian Rogers <>
Acked-by: Jiri Olsa <>
Cc: Alexander Shishkin <>
Cc: Andi Kleen <>
Cc: John Garry <>
Cc: Kajol Jain <>
Cc: Kan Liang <>
Cc: Mark Rutland <>
Cc: Namhyung Kim <>
Cc: Paul Clarke <>
Cc: Peter Zijlstra <>
Cc: Stephane Eranian <>
Signed-off-by: Arnaldo Carvalho de Melo <>
diff --git a/tools/perf/tests/parse-metric.c b/tools/perf/tests/parse-metric.c
index 574b7e4..07b6f4e 100644
--- a/tools/perf/tests/parse-metric.c
+++ b/tools/perf/tests/parse-metric.c
@@ -109,6 +109,7 @@
 	struct evsel *evsel;
 	u64 count;
+	perf_stat__reset_shadow_stats();
 	evlist__for_each_entry(evlist, evsel) {
 		count = find_value(evsel->name, vals);
 		perf_stat__update_shadow_stats(evsel, count, 0, st);