| /* |
| * Copyright (c) 2016, 2018, 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 |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. |
| * |
| * This code is distributed in the hope that it will be useful, but WITHOUT |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| * |
| */ |
| |
| #include "precompiled.hpp" |
| #include "classfile/javaClasses.inline.hpp" |
| #include "classfile/symbolTable.hpp" |
| #include "jfr/jni/jfrGetAllEventClasses.hpp" |
| #include "jfr/jni/jfrJavaSupport.hpp" |
| #include "jfr/support/jfrEventClass.hpp" |
| #include "oops/instanceKlass.hpp" |
| #include "memory/allocation.inline.hpp" |
| #include "memory/resourceArea.hpp" |
| #include "runtime/handles.inline.hpp" |
| #include "runtime/mutexLocker.hpp" |
| #include "runtime/safepoint.hpp" |
| #include "runtime/thread.inline.hpp" |
| #include "utilities/growableArray.hpp" |
| #include "utilities/stack.inline.hpp" |
| |
| // incremented during class unloading (safepoint) for each unloaded event class |
| static jlong unloaded_event_classes = 0; |
| |
| jlong JfrEventClasses::unloaded_event_classes_count() { |
| return unloaded_event_classes; |
| } |
| |
| void JfrEventClasses::increment_unloaded_event_class() { |
| // incremented during class unloading (safepoint) for each unloaded event class |
| assert(SafepointSynchronize::is_at_safepoint(), "invariant"); |
| ++unloaded_event_classes; |
| } |
| |
| static jobject empty_java_util_arraylist = NULL; |
| |
| static oop new_java_util_arraylist(TRAPS) { |
| DEBUG_ONLY(JfrJavaSupport::check_java_thread_in_vm(THREAD)); |
| JavaValue result(T_OBJECT); |
| JfrJavaArguments args(&result, "java/util/ArrayList", "<init>", "()V", CHECK_NULL); |
| JfrJavaSupport::new_object(&args, CHECK_NULL); |
| return (oop)result.get_jobject(); |
| } |
| |
| static bool initialize(TRAPS) { |
| static bool initialized = false; |
| if (!initialized) { |
| unloaded_event_classes = 0; |
| assert(NULL == empty_java_util_arraylist, "invariant"); |
| const oop array_list = new_java_util_arraylist(CHECK_false); |
| empty_java_util_arraylist = JfrJavaSupport::global_jni_handle(array_list, THREAD); |
| initialized = empty_java_util_arraylist != NULL; |
| } |
| return initialized; |
| } |
| |
| /* |
| * Abstract klasses are filtered out unconditionally. |
| * If a klass is not yet initialized, i.e yet to run its <clinit> |
| * it is also filtered out so we don't accidentally |
| * trigger initialization. |
| */ |
| static bool is_whitelisted(const Klass* k) { |
| assert(k != NULL, "invariant"); |
| return !(k->is_abstract() || k->should_be_initialized()); |
| } |
| |
| static void fill_klasses(GrowableArray<const void*>& event_subklasses, const Klass* event_klass, Thread* thread) { |
| assert(event_subklasses.length() == 0, "invariant"); |
| assert(event_klass != NULL, "invariant"); |
| DEBUG_ONLY(JfrJavaSupport::check_java_thread_in_vm(thread)); |
| |
| Stack<const Klass*, mtTracing> mark_stack; |
| MutexLocker ml(Compile_lock, thread); |
| mark_stack.push(event_klass->subklass()); |
| |
| while (!mark_stack.is_empty()) { |
| const Klass* const current = mark_stack.pop(); |
| assert(current != NULL, "null element in stack!"); |
| |
| if (is_whitelisted(current)) { |
| event_subklasses.append(current); |
| } |
| |
| // subclass (depth) |
| const Klass* next_klass = current->subklass(); |
| if (next_klass != NULL) { |
| mark_stack.push(next_klass); |
| } |
| |
| // siblings (breadth) |
| next_klass = current->next_sibling(); |
| if (next_klass != NULL) { |
| mark_stack.push(next_klass); |
| } |
| } |
| assert(mark_stack.is_empty(), "invariant"); |
| } |
| |
| static void transform_klasses_to_local_jni_handles(GrowableArray<const void*>& event_subklasses, Thread* thread) { |
| assert(event_subklasses.is_nonempty(), "invariant"); |
| DEBUG_ONLY(JfrJavaSupport::check_java_thread_in_vm(thread)); |
| |
| for (int i = 0; i < event_subklasses.length(); ++i) { |
| const InstanceKlass* k = static_cast<const InstanceKlass*>(event_subklasses.at(i)); |
| assert(is_whitelisted(k), "invariant"); |
| event_subklasses.at_put(i, JfrJavaSupport::local_jni_handle(k->java_mirror(), thread)); |
| } |
| } |
| |
| static const int initial_size_growable_array = 64; |
| |
| jobject JfrEventClasses::get_all_event_classes(TRAPS) { |
| DEBUG_ONLY(JfrJavaSupport::check_java_thread_in_vm(THREAD)); |
| initialize(THREAD); |
| assert(empty_java_util_arraylist != NULL, "should have been setup already!"); |
| static const char jdk_jfr_event_name[] = "jdk/jfr/Event"; |
| unsigned int unused_hash = 0; |
| Symbol* const event_klass_name = SymbolTable::lookup_only(jdk_jfr_event_name, sizeof jdk_jfr_event_name - 1, unused_hash); |
| |
| if (NULL == event_klass_name) { |
| // not loaded yet |
| return empty_java_util_arraylist; |
| } |
| |
| const Klass* const klass = SystemDictionary::resolve_or_null(event_klass_name, THREAD); |
| assert(klass != NULL, "invariant"); |
| assert(JdkJfrEvent::is(klass), "invariant"); |
| |
| if (klass->subklass() == NULL) { |
| return empty_java_util_arraylist; |
| } |
| |
| ResourceMark rm(THREAD); |
| GrowableArray<const void*> event_subklasses(THREAD, initial_size_growable_array); |
| fill_klasses(event_subklasses, klass, THREAD); |
| |
| if (event_subklasses.is_empty()) { |
| return empty_java_util_arraylist; |
| } |
| |
| transform_klasses_to_local_jni_handles(event_subklasses, THREAD); |
| |
| Handle h_array_list(THREAD, new_java_util_arraylist(THREAD)); |
| assert(h_array_list.not_null(), "invariant"); |
| |
| static const char add_method_name[] = "add"; |
| static const char add_method_signature[] = "(Ljava/lang/Object;)Z"; |
| const Klass* const array_list_klass = JfrJavaSupport::klass(empty_java_util_arraylist); |
| assert(array_list_klass != NULL, "invariant"); |
| |
| const Symbol* const add_method_sym = SymbolTable::lookup(add_method_name, sizeof add_method_name - 1, THREAD); |
| assert(add_method_sym != NULL, "invariant"); |
| |
| const Symbol* const add_method_sig_sym = SymbolTable::lookup(add_method_signature, sizeof add_method_signature - 1, THREAD); |
| assert(add_method_signature != NULL, "invariant"); |
| |
| JavaValue result(T_BOOLEAN); |
| for (int i = 0; i < event_subklasses.length(); ++i) { |
| const jclass clazz = (const jclass)event_subklasses.at(i); |
| assert(JdkJfrEvent::is_subklass(clazz), "invariant"); |
| JfrJavaArguments args(&result, array_list_klass, add_method_sym, add_method_sig_sym); |
| args.set_receiver(h_array_list()); |
| args.push_jobject(clazz); |
| JfrJavaSupport::call_virtual(&args, THREAD); |
| if (HAS_PENDING_EXCEPTION || JNI_FALSE == result.get_jboolean()) { |
| return empty_java_util_arraylist; |
| } |
| } |
| return JfrJavaSupport::local_jni_handle(h_array_list(), THREAD); |
| } |