diff -r a07d5cb03a85 -r 396442cd7e6a contrib/perf.py
--- a/contrib/perf.py	Mon May 03 12:22:16 2021 +0200
+++ b/contrib/perf.py	Mon May 03 12:22:26 2021 +0200
@@ -3040,7 +3040,9 @@
         # compatibility with <= hg-5.8
         indexfile = getattr(orig, 'indexfile')
     origindexpath = orig.opener.join(indexfile)
-    origdatapath = orig.opener.join(orig.datafile)
+
+    datafile = getattr(orig, '_datafile', getattr(orig, 'datafile'))
+    origdatapath = orig.opener.join(datafile)
     indexname = 'revlog.i'
     dataname = 'revlog.d'
 
@@ -3141,7 +3143,8 @@
                 indexfile = getattr(rl, 'indexfile')
             return getsvfs(repo)(indexfile)
         else:
-            return getsvfs(repo)(rl.datafile)
+            datafile = getattr(rl, 'datafile', getattr(rl, 'datafile'))
+            return getsvfs(repo)(datafile)
 
     def doread():
         rl.clearcaches()