8333542: Breakpoint in parallel code does not work

Co-authored-by: Chris Plummer <cjplummer@openjdk.org>
Reviewed-by: dholmes, vlivanov

src/hotspot/share/classfile/javaClasses.cpp

@@ -788,6 +788,7 @@ int java_lang_Class::_class_loader_offset;
 int java_lang_Class::_module_offset;
 int java_lang_Class::_protection_domain_offset;
 int java_lang_Class::_component_mirror_offset;
+int java_lang_Class::_init_lock_offset;
 int java_lang_Class::_signers_offset;
 int java_lang_Class::_name_offset;
 int java_lang_Class::_source_file_offset;
@@ -911,6 +912,12 @@ void java_lang_Class::initialize_mirror_fields(Klass* k,
                                                Handle protection_domain,
                                                Handle classData,
                                                TRAPS) {
+  // Allocate a simple java object for a lock.
+  // This needs to be a java object because during class initialization
+  // it can be held across a java call.
+  typeArrayOop r = oopFactory::new_typeArray(T_INT, 0, CHECK);
+  set_init_lock(mirror(), r);
+
   // Set protection domain also
   set_protection_domain(mirror(), protection_domain());
 
@@ -1132,6 +1139,10 @@ bool java_lang_Class::restore_archived_mirror(Klass *k,
   if (!k->is_array_klass()) {
     // - local static final fields with initial values were initialized at dump time
 
+    // create the init_lock
+    typeArrayOop r = oopFactory::new_typeArray(T_INT, 0, CHECK_(false));
+    set_init_lock(mirror(), r);
+
     if (protection_domain.not_null()) {
       set_protection_domain(mirror(), protection_domain());
     }
@@ -1196,6 +1207,15 @@ oop java_lang_Class::component_mirror(oop java_class) {
   return java_class->obj_field(_component_mirror_offset);
 }
 
+oop java_lang_Class::init_lock(oop java_class) {
+  assert(_init_lock_offset != 0, "must be set");
+  return java_class->obj_field(_init_lock_offset);
+}
+void java_lang_Class::set_init_lock(oop java_class, oop init_lock) {
+  assert(_init_lock_offset != 0, "must be set");
+  java_class->obj_field_put(_init_lock_offset, init_lock);
+}
+
 objArrayOop java_lang_Class::signers(oop java_class) {
   assert(_signers_offset != 0, "must be set");
   return (objArrayOop)java_class->obj_field(_signers_offset);
@@ -1415,12 +1435,18 @@ void java_lang_Class::compute_offsets() {
   InstanceKlass* k = vmClasses::Class_klass();
   CLASS_FIELDS_DO(FIELD_COMPUTE_OFFSET);
 
+  // Init lock is a C union with component_mirror.  Only instanceKlass mirrors have
+  // init_lock and only ArrayKlass mirrors have component_mirror.  Since both are oops
+  // GC treats them the same.
+  _init_lock_offset = _component_mirror_offset;
+
   CLASS_INJECTED_FIELDS(INJECTED_FIELD_COMPUTE_OFFSET);
 }
 
 #if INCLUDE_CDS
 void java_lang_Class::serialize_offsets(SerializeClosure* f) {
   f->do_bool(&_offsets_computed);
+  f->do_u4((u4*)&_init_lock_offset);
 
   CLASS_FIELDS_DO(FIELD_SERIALIZE_OFFSET);
 

src/hotspot/share/classfile/javaClasses.hpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1997, 2023, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1997, 2024, 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
@@ -226,6 +226,7 @@ class java_lang_Class : AllStatic {
   static int _static_oop_field_count_offset;
 
   static int _protection_domain_offset;
+  static int _init_lock_offset;
   static int _signers_offset;
   static int _class_loader_offset;
   static int _module_offset;
@@ -240,6 +241,7 @@ class java_lang_Class : AllStatic {
   static GrowableArray<Klass*>* _fixup_mirror_list;
   static GrowableArray<Klass*>* _fixup_module_field_list;
 
+  static void set_init_lock(oop java_class, oop init_lock);
   static void set_protection_domain(oop java_class, oop protection_domain);
   static void set_class_loader(oop java_class, oop class_loader);
   static void set_component_mirror(oop java_class, oop comp_mirror);
@@ -292,6 +294,10 @@ class java_lang_Class : AllStatic {
 
   // Support for embedded per-class oops
   static oop  protection_domain(oop java_class);
+  static oop  init_lock(oop java_class);
+  static void clear_init_lock(oop java_class) {
+    set_init_lock(java_class, nullptr);
+  }
   static oop  component_mirror(oop java_class);
   static objArrayOop  signers(oop java_class);
   static void set_signers(oop java_class, objArrayOop signers);

src/hotspot/share/classfile/vmSymbols.hpp

@@ -557,6 +557,7 @@ class SerializeClosure;
   template(bool_array_signature,                      "[Z")                                       \
   template(byte_array_signature,                      "[B")                                       \
   template(char_array_signature,                      "[C")                                       \
+  template(int_array_signature,                       "[I")                                       \
   template(runnable_signature,                        "Ljava/lang/Runnable;")                     \
   template(continuation_signature,                    "Ljdk/internal/vm/Continuation;")           \
   template(continuationscope_signature,               "Ljdk/internal/vm/ContinuationScope;")      \

src/hotspot/share/interpreter/linkResolver.cpp

@@ -1824,7 +1824,7 @@ void LinkResolver::resolve_invokedynamic(CallInfo& result, const constantPoolHan
   // the interpreter or runtime performs a serialized check of
   // the relevant ResolvedIndyEntry::method field.  This is done by the caller
   // of this method, via CPC::set_dynamic_call, which uses
-  // a lock to do the final serialization of updates
+  // an ObjectLocker to do the final serialization of updates
   // to ResolvedIndyEntry state, including method.
 
   // Log dynamic info to CDS classlist.

src/hotspot/share/oops/cpCache.cpp

@@ -56,6 +56,7 @@
 #include "runtime/atomic.hpp"
 #include "runtime/handles.inline.hpp"
 #include "runtime/mutexLocker.hpp"
+#include "runtime/synchronizer.hpp"
 #include "runtime/vm_version.hpp"
 #include "utilities/macros.hpp"
 
@@ -174,7 +175,7 @@ void ConstantPoolCache::set_direct_or_vtable_call(Bytecodes::Code invoke_code,
     }
     if (invoke_code == Bytecodes::_invokestatic) {
       assert(method->method_holder()->is_initialized() ||
-             method->method_holder()->is_init_thread(JavaThread::current()),
+             method->method_holder()->is_reentrant_initialization(JavaThread::current()),
              "invalid class initialization state for invoke_static");
 
       if (!VM_Version::supports_fast_class_init_checks() && method->needs_clinit_barrier()) {
@@ -269,11 +270,20 @@ ResolvedMethodEntry* ConstantPoolCache::set_method_handle(int method_index, cons
   // A losing writer waits on the lock until the winner writes the method and leaves
   // the lock, so that when the losing writer returns, he can use the linked
   // cache entry.
+
   // Lock fields to write
   Bytecodes::Code invoke_code = Bytecodes::_invokehandle;
-  MutexLocker ml(constant_pool()->pool_holder()->init_monitor());
-  ResolvedMethodEntry* method_entry = resolved_method_entry_at(method_index);
 
+  JavaThread* current = JavaThread::current();
+  objArrayHandle resolved_references(current, constant_pool()->resolved_references());
+  // Use the resolved_references() lock for this cpCache entry.
+  // resolved_references are created for all classes with Invokedynamic, MethodHandle
+  // or MethodType constant pool cache entries.
+  assert(resolved_references() != nullptr,
+         "a resolved_references array should have been created for this class");
+  ObjectLocker ol(resolved_references, current);
+
+  ResolvedMethodEntry* method_entry = resolved_method_entry_at(method_index);
   if (method_entry->is_resolved(invoke_code)) {
     return method_entry;
   }
@@ -311,7 +321,6 @@ ResolvedMethodEntry* ConstantPoolCache::set_method_handle(int method_index, cons
   // Store appendix, if any.
   if (has_appendix) {
     const int appendix_index = method_entry->resolved_references_index();
-    objArrayOop resolved_references = constant_pool()->resolved_references();
     assert(appendix_index >= 0 && appendix_index < resolved_references->length(), "oob");
     assert(resolved_references->obj_at(appendix_index) == nullptr, "init just once");
     resolved_references->obj_at_put(appendix_index, appendix());
@@ -587,7 +596,14 @@ bool ConstantPoolCache::save_and_throw_indy_exc(
   assert(PENDING_EXCEPTION->is_a(vmClasses::LinkageError_klass()),
          "No LinkageError exception");
 
-  MutexLocker ml(THREAD, cpool->pool_holder()->init_monitor());
+  // Use the resolved_references() lock for this cpCache entry.
+  // resolved_references are created for all classes with Invokedynamic, MethodHandle
+  // or MethodType constant pool cache entries.
+  JavaThread* current = THREAD;
+  objArrayHandle resolved_references(current, cpool->resolved_references());
+  assert(resolved_references() != nullptr,
+         "a resolved_references array should have been created for this class");
+  ObjectLocker ol(resolved_references, current);
 
   // if the indy_info is resolved or the indy_resolution_failed flag is set then another
   // thread either succeeded in resolving the method or got a LinkageError
@@ -610,21 +626,29 @@ bool ConstantPoolCache::save_and_throw_indy_exc(
 
 oop ConstantPoolCache::set_dynamic_call(const CallInfo &call_info, int index) {
   ResourceMark rm;
-  MutexLocker ml(constant_pool()->pool_holder()->init_monitor());
+
+  // Use the resolved_references() lock for this cpCache entry.
+  // resolved_references are created for all classes with Invokedynamic, MethodHandle
+  // or MethodType constant pool cache entries.
+  JavaThread* current = JavaThread::current();
+  constantPoolHandle cp(current, constant_pool());
+
+  objArrayHandle resolved_references(current, cp->resolved_references());
+  assert(resolved_references() != nullptr,
+         "a resolved_references array should have been created for this class");
+  ObjectLocker ol(resolved_references, current);
   assert(index >= 0, "Indy index must be positive at this point");
 
   if (resolved_indy_entry_at(index)->method() != nullptr) {
-    return constant_pool()->resolved_reference_from_indy(index);
+    return cp->resolved_reference_from_indy(index);
   }
 
   if (resolved_indy_entry_at(index)->resolution_failed()) {
     // Before we got here, another thread got a LinkageError exception during
     // resolution.  Ignore our success and throw their exception.
     guarantee(index >= 0, "Invalid indy index");
     int encoded_index = ResolutionErrorTable::encode_indy_index(index);
-    JavaThread* THREAD = JavaThread::current(); // For exception macros.
-    constantPoolHandle cp(THREAD, constant_pool());
-    ConstantPool::throw_resolution_error(cp, encoded_index, THREAD);
+    ConstantPool::throw_resolution_error(cp, encoded_index, current);
     return nullptr;
   }
 
@@ -648,7 +672,6 @@ oop ConstantPoolCache::set_dynamic_call(const CallInfo &call_info, int index) {
 
   if (has_appendix) {
     const int appendix_index = resolved_indy_entry_at(index)->resolved_references_index();
-    objArrayOop resolved_references = constant_pool()->resolved_references();
     assert(appendix_index >= 0 && appendix_index < resolved_references->length(), "oob");
     assert(resolved_references->obj_at(appendix_index) == nullptr, "init just once");
     resolved_references->obj_at_put(appendix_index, appendix());