--- a/hotspot/src/share/vm/gc/shared/referencePendingListLocker.cpp Tue Aug 30 12:48:03 2016 +0300
+++ /dev/null Thu Jan 01 00:00:00 1970 +0000
@@ -1,222 +0,0 @@
-/*
- * Copyright (c) 2016, 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.hpp"
-#include "classfile/systemDictionary.hpp"
-#include "gc/shared/collectedHeap.hpp"
-#include "gc/shared/referencePendingListLocker.hpp"
-#include "memory/universe.hpp"
-#include "runtime/javaCalls.hpp"
-#include "utilities/preserveException.hpp"
-
-ReferencePendingListLockerThread::ReferencePendingListLockerThread() :
- JavaThread(&start),
- _monitor(Monitor::nonleaf, "ReferencePendingListLocker", false, Monitor::_safepoint_check_sometimes),
- _message(NONE) {}
-
-ReferencePendingListLockerThread* ReferencePendingListLockerThread::create(TRAPS) {
- // Create Java thread objects
- instanceKlassHandle thread_klass = SystemDictionary::resolve_or_fail(vmSymbols::java_lang_Thread(), true, CHECK_NULL);
- instanceHandle thread_object = thread_klass->allocate_instance_handle(CHECK_NULL);
- Handle thread_name = java_lang_String::create_from_str("Reference Pending List Locker", CHECK_NULL);
- Handle thread_group = Universe::system_thread_group();
- JavaValue result(T_VOID);
- JavaCalls::call_special(&result,
- thread_object,
- thread_klass,
- vmSymbols::object_initializer_name(),
- vmSymbols::threadgroup_string_void_signature(),
- thread_group,
- thread_name,
- CHECK_NULL);
-
- {
- MutexLocker ml(Threads_lock);
-
- // Allocate thread
- ReferencePendingListLockerThread* thread = new ReferencePendingListLockerThread();
- if (thread == NULL || thread->osthread() == NULL) {
- vm_exit_during_initialization("java.lang.OutOfMemoryError",
- os::native_thread_creation_failed_msg());
- }
-
- // Initialize thread
- java_lang_Thread::set_thread(thread_object(), thread);
- java_lang_Thread::set_priority(thread_object(), NearMaxPriority);
- java_lang_Thread::set_daemon(thread_object());
- thread->set_threadObj(thread_object());
-
- // Start thread
- Threads::add(thread);
- Thread::start(thread);
-
- return thread;
- }
-}
-
-void ReferencePendingListLockerThread::start(JavaThread* thread, TRAPS) {
- ReferencePendingListLockerThread* locker_thread = static_cast<ReferencePendingListLockerThread*>(thread);
- locker_thread->receive_and_handle_messages();
-}
-
-bool ReferencePendingListLockerThread::is_hidden_from_external_view() const {
- return true;
-}
-
-void ReferencePendingListLockerThread::send_message(Message message) {
- assert(message != NONE, "Should not be none");
- MonitorLockerEx ml(&_monitor, Monitor::_no_safepoint_check_flag);
-
- // Wait for completion of current message
- while (_message != NONE) {
- ml.wait(Monitor::_no_safepoint_check_flag);
- }
-
- // Send new message
- _message = message;
- ml.notify_all();
-
- // Wait for completion of new message
- while (_message != NONE) {
- ml.wait(Monitor::_no_safepoint_check_flag);
- }
-}
-
-void ReferencePendingListLockerThread::receive_and_handle_messages() {
- ReferencePendingListLocker pending_list_locker;
- MonitorLockerEx ml(&_monitor);
-
- // Main loop, never terminates
- for (;;) {
- // Wait for message
- while (_message == NONE) {
- ml.wait();
- }
-
- // Handle message
- if (_message == LOCK) {
- pending_list_locker.lock();
- } else if (_message == UNLOCK) {
- pending_list_locker.unlock();
- } else {
- ShouldNotReachHere();
- }
-
- // Clear message
- _message = NONE;
- ml.notify_all();
- }
-}
-
-void ReferencePendingListLockerThread::lock() {
- send_message(LOCK);
-}
-
-void ReferencePendingListLockerThread::unlock() {
- send_message(UNLOCK);
-}
-
-bool ReferencePendingListLocker::_is_initialized = false;
-ReferencePendingListLockerThread* ReferencePendingListLocker::_locker_thread = NULL;
-
-void ReferencePendingListLocker::initialize(bool needs_locker_thread, TRAPS) {
- if (needs_locker_thread) {
- _locker_thread = ReferencePendingListLockerThread::create(CHECK);
- }
-
- _is_initialized = true;
-}
-
-bool ReferencePendingListLocker::is_initialized() {
- return _is_initialized;
-}
-
-bool ReferencePendingListLocker::is_locked_by_self() {
- oop pending_list_lock = java_lang_ref_Reference::pending_list_lock();
- if (pending_list_lock == NULL) {
- return false;
- }
-
- JavaThread* thread = JavaThread::current();
- Handle handle(thread, pending_list_lock);
- return ObjectSynchronizer::current_thread_holds_lock(thread, handle);
-}
-
-void ReferencePendingListLocker::lock() {
- assert(!Heap_lock->owned_by_self(), "Heap_lock must not be owned by requesting thread");
-
- if (Thread::current()->is_Java_thread()) {
- assert(java_lang_ref_Reference::pending_list_lock() != NULL, "Not initialized");
-
- // We may enter this with a pending exception
- PRESERVE_EXCEPTION_MARK;
-
- HandleMark hm;
- Handle handle(THREAD, java_lang_ref_Reference::pending_list_lock());
-
- // Lock
- ObjectSynchronizer::fast_enter(handle, &_basic_lock, false, THREAD);
-
- assert(is_locked_by_self(), "Locking failed");
-
- if (HAS_PENDING_EXCEPTION) {
- CLEAR_PENDING_EXCEPTION;
- }
- } else {
- // Delegate operation to locker thread
- assert(_locker_thread != NULL, "Locker thread not created");
- _locker_thread->lock();
- }
-}
-
-void ReferencePendingListLocker::unlock() {
- if (Thread::current()->is_Java_thread()) {
- assert(java_lang_ref_Reference::pending_list_lock() != NULL, "Not initialized");
-
- // We may enter this with a pending exception
- PRESERVE_EXCEPTION_MARK;
-
- HandleMark hm;
- Handle handle(THREAD, java_lang_ref_Reference::pending_list_lock());
-
- assert(is_locked_by_self(), "Should be locked by self");
-
- // Notify waiters if the pending list is non-empty
- if (java_lang_ref_Reference::pending_list() != NULL) {
- ObjectSynchronizer::notifyall(handle, THREAD);
- }
-
- // Unlock
- ObjectSynchronizer::fast_exit(handle(), &_basic_lock, THREAD);
-
- if (HAS_PENDING_EXCEPTION) {
- CLEAR_PENDING_EXCEPTION;
- }
- } else {
- // Delegate operation to locker thread
- assert(_locker_thread != NULL, "Locker thread not created");
- _locker_thread->unlock();
- }
-}