Index: generic/nsfInt.h
===================================================================
diff -u -r19ef72a5f87241def42fa2a2ec15e28a8717b59b -r0078146a2bcee10f8f7f65313b86b288f6d2f652
--- generic/nsfInt.h	(.../nsfInt.h)	(revision 19ef72a5f87241def42fa2a2ec15e28a8717b59b)
+++ generic/nsfInt.h	(.../nsfInt.h)	(revision 0078146a2bcee10f8f7f65313b86b288f6d2f652)
@@ -28,9 +28,29 @@
 #endif
 
 #if defined(NSF_PROFILE)
-#  include <sys/time.h>
+# include <sys/time.h>
 #endif
 
+#if defined(NSF_DTRACE)
+# include "nsfDTrace.h"
+# if defined(__GNUC__) && __GNUC__ > 2
+/* Use gcc branch prediction hint to minimize cost of DTrace ENABLED checks. */
+#  define unlikely(x) (__builtin_expect((x), 0))
+# else
+#  define unlikely(x) (x)
+# endif
+# define NSF_DTRACE_METHOD_ENTRY_ENABLED()     		unlikely(NSF_METHOD_ENTRY_ENABLED())
+# define NSF_DTRACE_METHOD_RETURN_ENABLED()    		unlikely(NSF_METHOD_RETURN_ENABLED())
+# define NSF_DTRACE_METHOD_ENTRY(a0, a1, a2, a3)	NSF_METHOD_ENTRY(a0, a1, a2, a3)
+# define NSF_DTRACE_METHOD_RETURN(a0, a1, a2)          	NSF_METHOD_RETURN(a0, a1, a2)
+#else
+# define NSF_DTRACE_METHOD_ENTRY_ENABLED()     		0
+# define NSF_DTRACE_METHOD_RETURN_ENABLED()    		0
+# define NSF_DTRACE_METHOD_ENTRY(a0, a1, a2, a3)       	{}
+# define NSF_DTRACE_METHOD_RETURN(a0, a1, a2)      	{}
+#endif
+
+
 #ifdef DMALLOC
 #  include "dmalloc.h"
 #endif