From ea07e719ca255d0da1966118c464ee23f4dc44da Mon Sep 17 00:00:00 2001
From: Aleksey Shipilev <shade@openjdk.org>
Date: Tue, 8 Apr 2025 08:12:59 +0000
Subject: [PATCH] 8352256: ObjectSynchronizer::quick_notify misses JFR event
 notification path

Reviewed-by: dholmes, coleenp, mgronlun
---
 src/hotspot/share/runtime/objectMonitor.cpp | 12 ++++++++++++
 src/hotspot/share/runtime/objectMonitor.hpp |  2 ++
 src/hotspot/share/runtime/synchronizer.cpp  | 10 +++-------
 3 files changed, 17 insertions(+), 7 deletions(-)

diff --git a/src/hotspot/share/runtime/objectMonitor.cpp b/src/hotspot/share/runtime/objectMonitor.cpp
index e280de6baf1..03228d0cb12 100644
--- a/src/hotspot/share/runtime/objectMonitor.cpp
+++ b/src/hotspot/share/runtime/objectMonitor.cpp
@@ -2058,6 +2058,12 @@ void ObjectMonitor::notify(TRAPS) {
     return;
   }
 
+  quick_notify(current);
+}
+
+void ObjectMonitor::quick_notify(JavaThread* current) {
+  assert(has_owner(current), "Precondition");
+
   EventJavaMonitorNotify event;
   DTRACE_MONITOR_PROBE(notify, this, object(), current);
   int tally = notify_internal(current) ? 1 : 0;
@@ -2080,6 +2086,12 @@ void ObjectMonitor::notifyAll(TRAPS) {
     return;
   }
 
+  quick_notifyAll(current);
+}
+
+void ObjectMonitor::quick_notifyAll(JavaThread* current) {
+  assert(has_owner(current), "Precondition");
+
   EventJavaMonitorNotify event;
   DTRACE_MONITOR_PROBE(notifyAll, this, object(), current);
   int tally = 0;
diff --git a/src/hotspot/share/runtime/objectMonitor.hpp b/src/hotspot/share/runtime/objectMonitor.hpp
index d24201fafe4..729316811c2 100644
--- a/src/hotspot/share/runtime/objectMonitor.hpp
+++ b/src/hotspot/share/runtime/objectMonitor.hpp
@@ -385,6 +385,8 @@ class ObjectMonitor : public CHeapObj<mtObjectMonitor> {
   void      wait(jlong millis, bool interruptible, TRAPS);
   void      notify(TRAPS);
   void      notifyAll(TRAPS);
+  void      quick_notify(JavaThread* current);
+  void      quick_notifyAll(JavaThread* current);
 
   void      print() const;
 #ifdef ASSERT
diff --git a/src/hotspot/share/runtime/synchronizer.cpp b/src/hotspot/share/runtime/synchronizer.cpp
index 73dd9d5330e..d608ffbdc02 100644
--- a/src/hotspot/share/runtime/synchronizer.cpp
+++ b/src/hotspot/share/runtime/synchronizer.cpp
@@ -368,16 +368,12 @@ bool ObjectSynchronizer::quick_notify(oopDesc* obj, JavaThread* current, bool al
 
     if (mon->first_waiter() != nullptr) {
       // We have one or more waiters. Since this is an inflated monitor
-      // that we own, we can transfer one or more threads from the waitset
-      // to the entry_list here and now, avoiding the slow-path.
+      // that we own, we quickly notify them here and now, avoiding the slow-path.
       if (all) {
-        DTRACE_MONITOR_PROBE(notifyAll, mon, obj, current);
+        mon->quick_notifyAll(current);
       } else {
-        DTRACE_MONITOR_PROBE(notify, mon, obj, current);
+        mon->quick_notify(current);
       }
-      do {
-        mon->notify_internal(current);
-      } while (mon->first_waiter() != nullptr && all);
     }
     return true;
   }