diff --git a/tools/funcslower.py b/tools/funcslower.py
index b8ef230ae9e4..7ac6c6d0208b 100755
--- a/tools/funcslower.py
+++ b/tools/funcslower.py
@@ -151,7 +151,7 @@
 if args.arguments:
     bpf_text = "#define GRAB_ARGS\n" + bpf_text
 if args.tgid:
-    bpf_text = bpf_text.replace('TGID_FILTER', 'tgid != %d' % tgid)
+    bpf_text = bpf_text.replace('TGID_FILTER', 'tgid != %d' % args.tgid)
 else:
     bpf_text = bpf_text.replace('TGID_FILTER', '0')