[XFRM]: Add packet processing statistics option.

Signed-off-by: Masahide NAKAMURA <nakam@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/xfrm/Kconfig b/net/xfrm/Kconfig
index 577a4f82..6b5b50f 100644
--- a/net/xfrm/Kconfig
+++ b/net/xfrm/Kconfig
@@ -35,6 +35,16 @@
 
 	  If unsure, say N.
 
+config XFRM_STATISTICS
+	bool "Transformation statistics (EXPERIMENTAL)"
+	depends on XFRM && PROC_FS && EXPERIMENTAL
+	---help---
+	  This statistics is not a SNMP/MIB specification but shows
+	  statistics about transformation error (or almost error) factor
+	  at packet processing for developer.
+
+	  If unsure, say N.
+
 config NET_KEY
 	tristate "PF_KEY sockets"
 	select XFRM