src/hotspot/share/prims/jvmtiEnvBase.cpp

*** 968,59 ***
        NULL, 0, 0, NULL, 0, NULL
    };
  
    uint32_t debug_bits = 0;
    // first derive the object's owner and entry_count (if any)
!   {
!     // Revoke any biases before querying the mark word
!     BiasedLocking::revoke_at_safepoint(hobj);
! 
-     address owner = NULL;
-     {
-       markWord mark = hobj()->mark();
- 
-       if (!mark.has_monitor()) {
-         // this object has a lightweight monitor
  
!         if (mark.has_locker()) {
!           owner = (address)mark.locker(); // save the address of the Lock word
!         }
!         // implied else: no owner
!       } else {
-         // this object has a heavyweight monitor
-         mon = mark.monitor();
- 
-         // The owner field of a heavyweight monitor may be NULL for no
-         // owner, a JavaThread * or it may still be the address of the
-         // Lock word in a JavaThread's stack. A monitor can be inflated
-         // by a non-owning JavaThread, but only the owning JavaThread
-         // can change the owner field from the Lock word to the
-         // JavaThread * and it may not have done that yet.
-         owner = (address)mon->owner();
-       }
-     }
- 
-     if (owner != NULL) {
-       // This monitor is owned so we have to find the owning JavaThread.
-       owning_thread = Threads::owning_thread_from_monitor_owner(tlh.list(), owner);
-       assert(owning_thread != NULL, "owning JavaThread must not be NULL");
-       Handle     th(current_thread, owning_thread->threadObj());
-       ret.owner = (jthread)jni_reference(calling_thread, th);
-     }
- 
-     if (owning_thread != NULL) {  // monitor is owned
-       // The recursions field of a monitor does not reflect recursions
-       // as lightweight locks before inflating the monitor are not included.
-       // We have to count the number of recursive monitor entries the hard way.
-       // We pass a handle to survive any GCs along the way.
-       ret.entry_count = count_locked_objects(owning_thread, hobj);
-     }
-     // implied else: entry_count == 0
    }
  
    jint nWant = 0, nWait = 0;
!   if (mon != NULL) {
      // this object has a heavyweight monitor
      nWant = mon->contentions(); // # of threads contending for monitor
      nWait = mon->waiters();     // # of threads in Object.wait()
      ret.waiter_count = nWant + nWait;
      ret.notify_waiter_count = nWait;
--- 968,28 ---
        NULL, 0, 0, NULL, 0, NULL
    };
  
    uint32_t debug_bits = 0;
    // first derive the object's owner and entry_count (if any)
!   owning_thread = ObjectSynchronizer::get_lock_owner(tlh.list(), hobj);
!   if (owning_thread != NULL) {  // monitor is owned
!     Handle th(current_thread, owning_thread->threadObj());
!     ret.owner = (jthread)jni_reference(calling_thread, th);
  
!     // The recursions field of a monitor does not reflect recursions
!     // as lightweight locks before inflating the monitor are not included.
!     // We have to count the number of recursive monitor entries the hard way.
!     // We pass a handle to survive any GCs along the way.
!     ret.entry_count = count_locked_objects(owning_thread, hobj);
    }
+   // implied else: entry_count == 0
  
    jint nWant = 0, nWait = 0;
!   markWord mark = hobj->mark();
+   if (mark.has_monitor()) {
+     mon = mark.monitor();
+     assert(mon != NULL, "must have monitor");
      // this object has a heavyweight monitor
      nWant = mon->contentions(); // # of threads contending for monitor
      nWait = mon->waiters();     // # of threads in Object.wait()
      ret.waiter_count = nWant + nWait;
      ret.notify_waiter_count = nWait;