--- a/hotspot/src/share/vm/classfile/classLoader.cpp	Thu Jan 13 22:54:23 2011 -0800
+++ b/hotspot/src/share/vm/classfile/classLoader.cpp	Thu Oct 07 13:49:40 2010 -0700
@@ -1382,3 +1382,61 @@
 }
 
 #endif //PRODUCT
+
+// Please keep following two functions at end of this file. With them placed at top or in middle of the file,
+// they could get inlined by agressive compiler, an unknown trick, see bug 6966589.
+void PerfClassTraceTime::initialize() {
+  if (!UsePerfData) return;
+
+  if (_eventp != NULL) {
+    // increment the event counter
+    _eventp->inc();
+  }
+
+  // stop the current active thread-local timer to measure inclusive time
+  _prev_active_event = -1;
+  for (int i=0; i < EVENT_TYPE_COUNT; i++) {
+     if (_timers[i].is_active()) {
+       assert(_prev_active_event == -1, "should have only one active timer");
+       _prev_active_event = i;
+       _timers[i].stop();
+     }
+  }
+
+  if (_recursion_counters == NULL || (_recursion_counters[_event_type])++ == 0) {
+    // start the inclusive timer if not recursively called
+    _t.start();
+  }
+
+  // start thread-local timer of the given event type
+   if (!_timers[_event_type].is_active()) {
+    _timers[_event_type].start();
+  }
+}
+
+PerfClassTraceTime::~PerfClassTraceTime() {
+  if (!UsePerfData) return;
+
+  // stop the thread-local timer as the event completes
+  // and resume the thread-local timer of the event next on the stack
+  _timers[_event_type].stop();
+  jlong selftime = _timers[_event_type].ticks();
+
+  if (_prev_active_event >= 0) {
+    _timers[_prev_active_event].start();
+  }
+
+  if (_recursion_counters != NULL && --(_recursion_counters[_event_type]) > 0) return;
+
+  // increment the counters only on the leaf call
+  _t.stop();
+  _timep->inc(_t.ticks());
+  if (_selftimep != NULL) {
+    _selftimep->inc(selftime);
+  }
+  // add all class loading related event selftime to the accumulated time counter
+  ClassLoader::perf_accumulated_time()->inc(selftime);
+
+  // reset the timer
+  _timers[_event_type].reset();
+}