Index: head/cddl/usr.sbin/dtrace/Makefile
===================================================================
--- head/cddl/usr.sbin/dtrace/Makefile
+++ head/cddl/usr.sbin/dtrace/Makefile
@@ -1,5 +1,7 @@
 # $FreeBSD$
 
+.include <src.opts.mk>
+
 .PATH: ${.CURDIR}/../../../cddl/contrib/opensolaris/cmd/dtrace
 
 PROG=		dtrace
@@ -22,4 +24,8 @@
 
 LIBADD=	dtrace
 
+.if ${MK_DTRACE_TESTS} != "no"
+SUBDIR+=	tests
+.endif
+
 .include <bsd.prog.mk>
Index: head/share/mk/src.opts.mk
===================================================================
--- head/share/mk/src.opts.mk
+++ head/share/mk/src.opts.mk
@@ -178,6 +178,7 @@
 __DEFAULT_NO_OPTIONS = \
     BSD_GREP \
     CLANG_EXTRAS \
+    DTRACE_TESTS \
     EISA \
     HESIOD \
     LLDB \
@@ -318,6 +319,10 @@
 MK_AUTHPF:=	no
 .endif
 
+.if ${MK_TESTS} == "no"
+MK_DTRACE_TESTS:= no
+.endif
+
 .if ${MK_TEXTPROC} == "no"
 MK_GROFF:=	no
 .endif
Index: head/tools/build/options/WITH_DTRACE_TESTS
===================================================================
--- head/tools/build/options/WITH_DTRACE_TESTS
+++ head/tools/build/options/WITH_DTRACE_TESTS
@@ -0,0 +1,5 @@
+.\" $FreeBSD$
+Set to build and install the DTrace test suite in
+.Pa /usr/tests/cddl/usr.sbin/dtrace .
+This test suite is considered experimental on architectures other than
+amd64/amd64 and running it may cause system instability.