--- a/contrib/perf.py	Fri Oct 13 21:31:24 2017 +0200
+++ b/contrib/perf.py	Fri Oct 13 21:32:29 2017 +0200
@@ -150,6 +150,9 @@
     configitem('perf', 'stub',
         default=mercurial.configitems.dynamicdefault,
     )
+    configitem('perf', 'parentscount',
+        default=mercurial.configitems.dynamicdefault,
+    )
 except (ImportError, AttributeError):
     pass