diff --git a/sys/sys/dkstat.h b/sys/sys/dkstat.h
index 760219c190ef..f556ff28afbc 100644
--- a/sys/sys/dkstat.h
+++ b/sys/sys/dkstat.h
@@ -51,6 +51,7 @@
 
 #ifdef _KERNEL
 
+extern long cp_time[CPUSTATES];
 extern long tk_cancc;
 extern long tk_nin;
 extern long tk_nout;