8315884: New Object to ObjectMonitor mapping

src/hotspot/share/runtime/lightweightSynchronizer.cpp

@@ -25,18 +25,16 @@
 #include "precompiled.hpp"
 
 #include "classfile/vmSymbols.hpp"
-#include "javaThread.inline.hpp"
 #include "jfrfiles/jfrEventClasses.hpp"
 #include "logging/log.hpp"
-#include "logging/logStream.hpp"
 #include "memory/resourceArea.hpp"
 #include "nmt/memflags.hpp"
 #include "oops/oop.inline.hpp"
 #include "runtime/atomic.hpp"
 #include "runtime/basicLock.inline.hpp"
 #include "runtime/globals_extension.hpp"
 #include "runtime/interfaceSupport.inline.hpp"
-#include "runtime/javaThread.hpp"
+#include "runtime/javaThread.inline.hpp"
 #include "runtime/lightweightSynchronizer.hpp"
 #include "runtime/lockStack.inline.hpp"
 #include "runtime/mutexLocker.hpp"
@@ -85,7 +83,7 @@ class ObjectMonitorWorld : public CHeapObj<MEMFLAGS::mtObjectMonitor> {
     oop _obj;
 
   public:
-    Lookup(oop obj) : _obj(obj) {}
+    explicit Lookup(oop obj) : _obj(obj) {}
 
     uintx get_hash() const {
       uintx hash = _obj->mark().hash();
@@ -94,7 +92,6 @@ class ObjectMonitorWorld : public CHeapObj<MEMFLAGS::mtObjectMonitor> {
     }
 
     bool equals(ObjectMonitor** value) {
-      // The entry is going to be removed soon.
       assert(*value != nullptr, "must be");
       return (*value)->object_refers_to(_obj);
     }
@@ -109,7 +106,7 @@ class ObjectMonitorWorld : public CHeapObj<MEMFLAGS::mtObjectMonitor> {
     ObjectMonitor* _monitor;
 
   public:
-    LookupMonitor(ObjectMonitor* monitor) : _monitor(monitor) {}
+    explicit LookupMonitor(ObjectMonitor* monitor) : _monitor(monitor) {}
 
     uintx get_hash() const {
       return _monitor->hash();
@@ -343,22 +340,20 @@ class ObjectMonitorWorld : public CHeapObj<MEMFLAGS::mtObjectMonitor> {
 
 ObjectMonitorWorld* LightweightSynchronizer::_omworld = nullptr;
 
-ObjectMonitor* LightweightSynchronizer::get_or_insert_monitor_from_table(oop object, JavaThread* current, bool try_read, bool* inserted) {
+ObjectMonitor* LightweightSynchronizer::get_or_insert_monitor_from_table(oop object, JavaThread* current, bool* inserted) {
   assert(LockingMode == LM_LIGHTWEIGHT, "must be");
 
-  if (try_read) {
-    ObjectMonitor* monitor = get_monitor_from_table(current, object);
-    if (monitor != nullptr) {
-      *inserted = false;
-      return monitor;
-    }
+  ObjectMonitor* monitor = get_monitor_from_table(current, object);
+  if (monitor != nullptr) {
+    *inserted = false;
+    return monitor;
   }
 
   ObjectMonitor* alloced_monitor = new ObjectMonitor(object);
   alloced_monitor->set_owner_anonymous();
 
   // Try insert monitor
-  ObjectMonitor* monitor = add_monitor(current, alloced_monitor, object);
+  monitor = add_monitor(current, alloced_monitor, object);
 
   *inserted = alloced_monitor == monitor;
   if (!*inserted) {
@@ -389,13 +384,13 @@ static void post_monitor_inflate_event(EventJavaMonitorInflate* event,
 }
 
 
-ObjectMonitor* LightweightSynchronizer::get_or_insert_monitor(oop object, JavaThread* current, const ObjectSynchronizer::InflateCause cause, bool try_read) {
+ObjectMonitor* LightweightSynchronizer::get_or_insert_monitor(oop object, JavaThread* current, const ObjectSynchronizer::InflateCause cause) {
   assert(UseObjectMonitorTable, "must be");
 
   EventJavaMonitorInflate event;
 
   bool inserted;
-  ObjectMonitor* monitor = get_or_insert_monitor_from_table(object, current, try_read, &inserted);
+  ObjectMonitor* monitor = get_or_insert_monitor_from_table(object, current, &inserted);
 
   if (inserted) {
     // Hopefully the performance counters are allocated on distinct
@@ -745,7 +740,6 @@ void LightweightSynchronizer::exit(oop object, JavaThread* current) {
     }
   }
 
-  // Fast-locking does not use the 'lock' argument.
   while (mark.is_fast_locked()) {
     markWord unlocked_mark = mark.set_unlocked();
     markWord old_mark = mark;
@@ -966,8 +960,8 @@ ObjectMonitor* LightweightSynchronizer::inflate_fast_locked_object(oop object, J
   assert(!mark.is_unlocked(), "Cannot be unlocked");
 
   for (;;) {
-  // Fetch the monitor from the table
-    monitor = get_or_insert_monitor(object, current, cause, true /* try_read */);
+    // Fetch the monitor from the table
+    monitor = get_or_insert_monitor(object, current, cause);
 
     // ObjectMonitors are always inserted as anonymously owned, this thread is
     // the current holder of the monitor. So unless the entry is stale and
@@ -1043,7 +1037,7 @@ ObjectMonitor* LightweightSynchronizer::inflate_and_enter(oop object, JavaThread
 
   // Get or create the monitor
   if (monitor == nullptr) {
-    monitor = get_or_insert_monitor(object, current, cause, true /* try_read */);
+    monitor = get_or_insert_monitor(object, current, cause);
   }
 
   if (monitor->try_enter(locking_thread)) {

src/hotspot/share/runtime/lightweightSynchronizer.hpp

@@ -36,8 +36,8 @@ class LightweightSynchronizer : AllStatic {
 private:
   static ObjectMonitorWorld* _omworld;
 
-  static ObjectMonitor* get_or_insert_monitor_from_table(oop object, JavaThread* current, bool try_read, bool* inserted);
-  static ObjectMonitor* get_or_insert_monitor(oop object, JavaThread* current, const ObjectSynchronizer::InflateCause cause, bool try_read);
+  static ObjectMonitor* get_or_insert_monitor_from_table(oop object, JavaThread* current, bool* inserted);
+  static ObjectMonitor* get_or_insert_monitor(oop object, JavaThread* current, const ObjectSynchronizer::InflateCause cause);
 
   static ObjectMonitor* add_monitor(JavaThread* current, ObjectMonitor* monitor, oop obj);
   static bool remove_monitor(Thread* current, oop obj, ObjectMonitor* monitor);

src/hotspot/share/runtime/lockStack.inline.hpp

@@ -229,7 +229,7 @@ inline void OMCache::set_monitor(ObjectMonitor *monitor) {
 
   oop obj = monitor->object_peek();
   assert(obj != nullptr, "must be alive");
-  assert(monitor == LightweightSynchronizer::get_monitor_from_table(JavaThread::current(), obj), "must be exist in table");
+  assert(monitor == LightweightSynchronizer::get_monitor_from_table(JavaThread::current(), obj), "must exist in table");
 
   OMCacheEntry to_insert = {obj, monitor};
 

src/hotspot/share/runtime/objectMonitor.cpp

@@ -53,7 +53,6 @@
 #include "runtime/safefetch.hpp"
 #include "runtime/safepointMechanism.inline.hpp"
 #include "runtime/sharedRuntime.hpp"
-#include "runtime/synchronizer.hpp"
 #include "services/threadService.hpp"
 #include "utilities/debug.hpp"
 #include "utilities/dtrace.hpp"

src/hotspot/share/runtime/objectMonitor.hpp

@@ -190,7 +190,6 @@ class ObjectMonitor : public CHeapObj<mtObjectMonitor> {
 
   ObjectWaiter* volatile _WaitSet;  // LL of threads wait()ing on the monitor
   volatile int  _waiters;           // number of waiting threads
- private:
   volatile int _WaitSetLock;        // protects Wait Queue - simple spinlock
 
  public: