--- a/src/share/vm/prims/unsafe.cpp	Tue Apr 01 14:09:03 2014 +0200
+++ b/src/share/vm/prims/unsafe.cpp	Tue Apr 01 13:57:07 2014 +0200
@@ -44,6 +44,11 @@
  *      Implementation of class sun.misc.Unsafe
  */
 
+#ifndef USDT2
+HS_DTRACE_PROBE_DECL3(hotspot, thread__park__begin, uintptr_t, int, long long);
+HS_DTRACE_PROBE_DECL1(hotspot, thread__park__end, uintptr_t);
+HS_DTRACE_PROBE_DECL1(hotspot, thread__unpark, uintptr_t);
+#endif /* !USDT2 */
 
 #define MAX_OBJECT_SIZE \
   ( arrayOopDesc::header_size(T_DOUBLE) * HeapWordSize \
@@ -157,9 +162,6 @@
 
 #define GET_FIELD_VOLATILE(obj, offset, type_name, v) \
   oop p = JNIHandles::resolve(obj); \
-  if (support_IRIW_for_not_multiple_copy_atomic_cpu) { \
-    OrderAccess::fence(); \
-  } \
   volatile type_name v = OrderAccess::load_acquire((volatile type_name*)index_oop_from_field_offset_long(p, offset));
 
 #define SET_FIELD_VOLATILE(obj, offset, type_name, x) \
@@ -856,11 +858,6 @@
   strcpy(buf, "java/lang/");
   strcat(buf, ename);
   jclass cls = env->FindClass(buf);
-  if (env->ExceptionCheck()) {
-    env->ExceptionClear();
-    tty->print_cr("Unsafe: cannot throw %s because FindClass has failed", buf);
-    return;
-  }
   char* msg = NULL;
   env->ThrowNew(cls, msg);
 }
@@ -1209,12 +1206,20 @@
 UNSAFE_ENTRY(void, Unsafe_Park(JNIEnv *env, jobject unsafe, jboolean isAbsolute, jlong time))
   UnsafeWrapper("Unsafe_Park");
   EventThreadPark event;
-  HOTSPOT_THREAD_PARK_BEGIN((uintptr_t) thread->parker(), (int) isAbsolute, time);
-
+#ifndef USDT2
+  HS_DTRACE_PROBE3(hotspot, thread__park__begin, thread->parker(), (int) isAbsolute, time);
+#else /* USDT2 */
+   HOTSPOT_THREAD_PARK_BEGIN(
+                             (uintptr_t) thread->parker(), (int) isAbsolute, time);
+#endif /* USDT2 */
   JavaThreadParkedState jtps(thread, time != 0);
   thread->parker()->park(isAbsolute != 0, time);
-
-  HOTSPOT_THREAD_PARK_END((uintptr_t) thread->parker());
+#ifndef USDT2
+  HS_DTRACE_PROBE1(hotspot, thread__park__end, thread->parker());
+#else /* USDT2 */
+  HOTSPOT_THREAD_PARK_END(
+                          (uintptr_t) thread->parker());
+#endif /* USDT2 */
   if (event.should_commit()) {
     oop obj = thread->current_park_blocker();
     event.set_klass((obj != NULL) ? obj->klass() : NULL);
@@ -1253,7 +1258,12 @@
     }
   }
   if (p != NULL) {
-    HOTSPOT_THREAD_UNPARK((uintptr_t) p);
+#ifndef USDT2
+    HS_DTRACE_PROBE1(hotspot, thread__unpark, p);
+#else /* USDT2 */
+    HOTSPOT_THREAD_UNPARK(
+                          (uintptr_t) p);
+#endif /* USDT2 */
     p->unpark();
   }
 UNSAFE_END