8317422: [JVMCI] concurrency issue in MethodData creation

Reviewed-by: never, thartmann

Author: Doug Simon

src/hotspot/share/ci/ciReplay.cpp

@@ -843,9 +843,7 @@ class CompileReplay : public StackObj {
     // method to be rewritten (number of arguments at a call for instance)
     method->method_holder()->link_class(CHECK);
     assert(method->method_data() == nullptr, "Should only be initialized once");
-    ClassLoaderData* loader_data = method->method_holder()->class_loader_data();
-    MethodData* method_data = MethodData::allocate(loader_data, methodHandle(THREAD, method), CHECK);
-    method->set_method_data(method_data);
+    method->build_profiling_method_data(methodHandle(THREAD, method), CHECK);
 
     // collect and record all the needed information for later
     ciMethodDataRecord* rec = new_ciMethodData(method);

src/hotspot/share/jvmci/jvmciCompilerToVM.cpp

@@ -1282,6 +1282,18 @@ C2V_VMENTRY_0(jint, getLocalVariableTableLength, (JNIEnv* env, jobject, ARGUMENT
   return method->localvariable_table_length();
 C2V_END
 
+static MethodData* get_profiling_method_data(const methodHandle& method, TRAPS) {
+  MethodData* method_data = method->method_data();
+  if (method_data == nullptr) {
+    method->build_profiling_method_data(method, CHECK_NULL);
+    method_data = method->method_data();
+    if (method_data == nullptr) {
+      THROW_MSG_NULL(vmSymbols::java_lang_OutOfMemoryError(), "cannot allocate MethodData")
+    }
+  }
+  return method_data;
+}
+
 C2V_VMENTRY(void, reprofile, (JNIEnv* env, jobject, ARGUMENT_PAIR(method)))
   methodHandle method(THREAD, UNPACK_PAIR(Method, method));
   MethodCounters* mcs = method->method_counters();
@@ -1297,9 +1309,7 @@ C2V_VMENTRY(void, reprofile, (JNIEnv* env, jobject, ARGUMENT_PAIR(method)))
 
   MethodData* method_data = method->method_data();
   if (method_data == nullptr) {
-    ClassLoaderData* loader_data = method->method_holder()->class_loader_data();
-    method_data = MethodData::allocate(loader_data, method, CHECK);
-    method->set_method_data(method_data);
+    method_data = get_profiling_method_data(method, CHECK);
   } else {
     method_data->initialize();
   }
@@ -2976,12 +2986,7 @@ C2V_END
 
 C2V_VMENTRY_0(jlong, getFailedSpeculationsAddress, (JNIEnv* env, jobject, ARGUMENT_PAIR(method)))
   methodHandle method(THREAD, UNPACK_PAIR(Method, method));
-  MethodData* method_data = method->method_data();
-  if (method_data == nullptr) {
-    ClassLoaderData* loader_data = method->method_holder()->class_loader_data();
-    method_data = MethodData::allocate(loader_data, method, CHECK_0);
-    method->set_method_data(method_data);
-  }
+  MethodData* method_data = get_profiling_method_data(method, CHECK_0);
   return (jlong) method_data->get_failed_speculations_address();
 C2V_END
 

src/hotspot/share/oops/method.cpp

@@ -102,7 +102,7 @@ Method::Method(ConstMethod* xconst, AccessFlags access_flags, Symbol* name) {
   set_constMethod(xconst);
   set_access_flags(access_flags);
   set_intrinsic_id(vmIntrinsics::_none);
-  set_method_data(nullptr);
+  clear_method_data();
   clear_method_counters();
   set_vtable_index(Method::garbage_vtable_index);
 
@@ -127,7 +127,7 @@ void Method::deallocate_contents(ClassLoaderData* loader_data) {
   MetadataFactory::free_metadata(loader_data, constMethod());
   set_constMethod(nullptr);
   MetadataFactory::free_metadata(loader_data, method_data());
-  set_method_data(nullptr);
+  clear_method_data();
   MetadataFactory::free_metadata(loader_data, method_counters());
   clear_method_counters();
   // The nmethod will be gone when we get here.
@@ -1179,7 +1179,7 @@ void Method::unlink_method() {
   }
   NOT_PRODUCT(set_compiled_invocation_count(0);)
 
-  set_method_data(nullptr);
+  clear_method_data();
   clear_method_counters();
   remove_unshareable_flags();
 }

src/hotspot/share/oops/method.hpp

@@ -308,8 +308,6 @@ class Method : public Metadata {
     return _method_data;
   }
 
-  void set_method_data(MethodData* data);
-
   MethodCounters* method_counters() const {
     return _method_counters;
   }
@@ -361,6 +359,10 @@ class Method : public Metadata {
   // Either called with CompiledMethod_lock held or from constructor.
   void clear_code();
 
+  void clear_method_data() {
+    _method_data = nullptr;
+  }
+
 public:
   static void set_code(const methodHandle& mh, CompiledMethod* code);
   void set_adapter_entry(AdapterHandlerEntry* adapter) {

src/hotspot/share/oops/method.inline.hpp

@@ -39,13 +39,6 @@ inline address Method::from_interpreted_entry() const {
   return Atomic::load_acquire(&_from_interpreted_entry);
 }
 
-inline void Method::set_method_data(MethodData* data) {
-  // The store into method must be released. On platforms without
-  // total store order (TSO) the reference may become visible before
-  // the initialization of data otherwise.
-  Atomic::release_store(&_method_data, data);
-}
-
 inline CompiledMethod* Method::code() const {
   assert( check_code(), "" );
   return Atomic::load_acquire(&_code);