It can be convenient to have unnamed metric groups for the sake of
organizing other metrics and metric groups. An unspecified name
shouldn't contribute to the MetricGroup json value, so don't record
it.

Signed-off-by: Ian Rogers <irogers@google.com>
---
 tools/perf/pmu-events/metric.py | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/tools/perf/pmu-events/metric.py b/tools/perf/pmu-events/metric.py
index 1de4fb72c75e..847b614d40d5 100644
--- a/tools/perf/pmu-events/metric.py
+++ b/tools/perf/pmu-events/metric.py
@@ -455,7 +455,8 @@ class Metric:
 
   def AddToMetricGroup(self, group):
     """Callback used when being added to a MetricGroup."""
-    self.groups.add(group.name)
+    if group.name:
+      self.groups.add(group.name)
 
   def Flatten(self) -> Set['Metric']:
     """Return a leaf metric."""
-- 
2.51.0.318.gd7df087d1a-goog