Index: sys/kern/subr_syscall.c
===================================================================
--- sys/kern/subr_syscall.c
+++ sys/kern/subr_syscall.c
@@ -51,9 +51,6 @@
 #include <sys/dtrace_bsd.h>
 #include <cddl/compat/opensolaris/sys/cred.h>
 #include <cddl/dev/dtrace/dtrace_cddl.h>
-#define IS_FORK(code) \
-	((code == SYS_fork) || (code == SYS_vfork) ||		\
-	    (code == SYS_rfork) || (code == SYS_pdfork))
 #endif
 #include <security/audit/audit.h>
 
@@ -135,7 +132,7 @@
 		/* Give the syscall:::entry DTrace probe a chance to fire. */
 		if (systrace_probe_func != NULL && sa->callp->sy_entry != 0)
 			(*systrace_probe_func)(sa, SYSTRACE_ENTRY, 0);
-		if (IS_FORK(sa->code) && (sa->callp->sy_return != 0))
+		if (sa->callp->sy_return != 0)
 			td->td_dtrace->td_systrace_id = sa->callp->sy_return;
 #endif