src/hotspot/share/runtime/vframe.cpp

rev 58110 : v2.09a with 8235795, 8235931 and 8236035 extracted; rebased to jdk-14+28; merge with 8236035.patch.cr1; merge with 8235795.patch.cr1; merge with 8236035.patch.cr2; merge with 8235795.patch.cr2; merge with 8235795.patch.cr3.
rev 58111 : See CR9-to-CR10-changes; merge with jdk-15+11.

@@ -1,7 +1,7 @@
 /*
- * Copyright (c) 1997, 2019, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1997, 2020, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
  * under the terms of the GNU General Public License version 2 only, as
  * published by the Free Software Foundation.

@@ -120,12 +120,19 @@
   GrowableArray<MonitorInfo*>* mons = monitors();
   GrowableArray<MonitorInfo*>* result = new GrowableArray<MonitorInfo*>(mons->length());
   if (mons->is_empty()) return result;
 
   bool found_first_monitor = false;
-  ObjectMonitor *pending_monitor = thread()->current_pending_monitor();
-  ObjectMonitor *waiting_monitor = thread()->current_waiting_monitor();
+  // For all of the javaVFrame::locked_monitors()() call sites, we
+  // are either at a safepoint or the calling thread is operating
+  // on itself so this ObjectMonitorHandle is not strictly necessary.
+  ObjectMonitorHandle omh;
+  ObjectMonitor *waiting_monitor = thread()->current_waiting_monitor(&omh);
+  ObjectMonitor *pending_monitor = NULL;
+  if (waiting_monitor == NULL) {
+    pending_monitor = thread()->current_pending_monitor(&omh);
+  }
   oop pending_obj = (pending_monitor != NULL ? (oop) pending_monitor->object() : (oop) NULL);
   oop waiting_obj = (waiting_monitor != NULL ? (oop) waiting_monitor->object() : (oop) NULL);
 
   for (int index = (mons->length()-1); index >= 0; index--) {
     MonitorInfo* monitor = mons->at(index);

@@ -229,13 +236,16 @@
           // monitor before, then we need to see if we have completed
           // the lock or if we are blocked trying to acquire it. Only
           // an inflated monitor that is first on the monitor list in
           // the first frame can block us on a monitor enter.
           markWord mark = monitor->owner()->mark();
+          // The calling thread is operating on itself so this
+          // ObjectMonitorHandle is not strictly necessary.
+          ObjectMonitorHandle omh;
           if (mark.has_monitor() &&
               ( // we have marked ourself as pending on this monitor
-                mark.monitor() == thread()->current_pending_monitor() ||
+                mark.monitor() == thread()->current_pending_monitor(&omh) ||
                 // we are not the owner of this monitor
                 !mark.monitor()->is_entered(thread())
               )) {
             lock_state = "waiting to lock";
           }