1 /* 2 * Copyright (c) 2001, 2019, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 25 #include "precompiled.hpp" 26 #include "gc/shared/concurrentGCThread.hpp" 27 #include "runtime/atomic.hpp" 28 #include "runtime/init.hpp" 29 #include "runtime/mutexLocker.hpp" 30 #include "runtime/os.hpp" 31 32 ConcurrentGCThread::ConcurrentGCThread() : 33 _should_terminate(false), 34 _has_terminated(false) {} 35 36 void ConcurrentGCThread::create_and_start(ThreadPriority prio) { 37 if (os::create_thread(this, os::cgc_thread)) { 38 os::set_priority(this, prio); 39 os::start_thread(this); 40 } 41 } 42 43 void ConcurrentGCThread::run() { 44 // Setup handle area 45 set_active_handles(JNIHandleBlock::allocate_block()); 46 47 // Wait for initialization to complete 48 wait_init_completed(); 49 50 run_service(); 51 52 // Signal thread has terminated 53 MonitorLocker ml(Terminator_lock); 54 Atomic::release_store(&_has_terminated, true); 55 ml.notify_all(); 56 } 57 58 void ConcurrentGCThread::stop() { 59 assert(!should_terminate(), "Invalid state"); 60 assert(!has_terminated(), "Invalid state"); 61 62 // Signal thread to terminate 63 Atomic::release_store_fence(&_should_terminate, true); 64 65 stop_service(); 66 67 // Wait for thread to terminate 68 MonitorLocker ml(Terminator_lock); 69 while (!_has_terminated) { 70 ml.wait(); 71 } 72 } 73 74 bool ConcurrentGCThread::should_terminate() const { 75 return Atomic::load_acquire(&_should_terminate); 76 } 77 78 bool ConcurrentGCThread::has_terminated() const { 79 return Atomic::load_acquire(&_has_terminated); 80 }