1 /* 2 * Copyright (c) 2001, 2018, 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/g1/g1BarrierSet.hpp" 27 #include "gc/g1/g1ConcurrentRefine.hpp" 28 #include "gc/g1/g1ConcurrentRefineThread.hpp" 29 #include "gc/shared/suspendibleThreadSet.hpp" 30 #include "logging/log.hpp" 31 #include "memory/resourceArea.hpp" 32 #include "runtime/handles.inline.hpp" 33 #include "runtime/mutexLocker.hpp" 34 35 G1ConcurrentRefineThread::G1ConcurrentRefineThread(G1ConcurrentRefine* cr, uint worker_id) : 36 ConcurrentGCThread(), 37 _worker_id(worker_id), 38 _active(false), 39 _monitor(NULL), 40 _cr(cr), 41 _vtime_accum(0.0) 42 { 43 // Each thread has its own monitor. The i-th thread is responsible for signaling 44 // to thread i+1 if the number of buffers in the queue exceeds a threshold for this 45 // thread. Monitors are also used to wake up the threads during termination. 46 // The 0th (primary) worker is notified by mutator threads and has a special monitor. 47 if (!is_primary()) { 48 _monitor = new Monitor(Mutex::nonleaf, "Refinement monitor", true, 49 Monitor::_safepoint_check_never); 50 } else { 51 _monitor = DirtyCardQ_CBL_mon; 52 } 53 54 // set name 55 set_name("G1 Refine#%d", worker_id); 56 create_and_start(); 57 } 58 59 void G1ConcurrentRefineThread::wait_for_completed_buffers() { 60 MutexLockerEx x(_monitor, Mutex::_no_safepoint_check_flag); 61 while (!should_terminate() && !is_active()) { 62 _monitor->wait(Mutex::_no_safepoint_check_flag); 63 } 64 } 65 66 bool G1ConcurrentRefineThread::is_active() { 67 DirtyCardQueueSet& dcqs = G1BarrierSet::dirty_card_queue_set(); 68 return is_primary() ? dcqs.process_completed_buffers() : _active; 69 } 70 71 void G1ConcurrentRefineThread::activate() { 72 MutexLockerEx x(_monitor, Mutex::_no_safepoint_check_flag); 73 if (!is_primary()) { 74 set_active(true); 75 } else { 76 DirtyCardQueueSet& dcqs = G1BarrierSet::dirty_card_queue_set(); 77 dcqs.set_process_completed(true); 78 } 79 _monitor->notify(); 80 } 81 82 void G1ConcurrentRefineThread::deactivate() { 83 MutexLockerEx x(_monitor, Mutex::_no_safepoint_check_flag); 84 if (!is_primary()) { 85 set_active(false); 86 } else { 87 DirtyCardQueueSet& dcqs = G1BarrierSet::dirty_card_queue_set(); 88 dcqs.set_process_completed(false); 89 } 90 } 91 92 void G1ConcurrentRefineThread::run_service() { 93 _vtime_start = os::elapsedVTime(); 94 95 while (!should_terminate()) { 96 // Wait for work 97 wait_for_completed_buffers(); 98 if (should_terminate()) { 99 break; 100 } 101 102 size_t buffers_processed = 0; 103 log_debug(gc, refine)("Activated worker %d, on threshold: " SIZE_FORMAT ", current: " SIZE_FORMAT, 104 _worker_id, _cr->activation_threshold(_worker_id), 105 G1BarrierSet::dirty_card_queue_set().completed_buffers_num()); 106 107 { 108 SuspendibleThreadSetJoiner sts_join; 109 110 while (!should_terminate()) { 111 if (sts_join.should_yield()) { 112 sts_join.yield(); 113 continue; // Re-check for termination after yield delay. 114 } 115 116 if (!_cr->do_refinement_step(_worker_id)) { 117 break; 118 } 119 ++buffers_processed; 120 } 121 } 122 123 deactivate(); 124 log_debug(gc, refine)("Deactivated worker %d, off threshold: " SIZE_FORMAT 125 ", current: " SIZE_FORMAT ", processed: " SIZE_FORMAT, 126 _worker_id, _cr->deactivation_threshold(_worker_id), 127 G1BarrierSet::dirty_card_queue_set().completed_buffers_num(), 128 buffers_processed); 129 130 if (os::supports_vtime()) { 131 _vtime_accum = (os::elapsedVTime() - _vtime_start); 132 } else { 133 _vtime_accum = 0.0; 134 } 135 } 136 137 log_debug(gc, refine)("Stopping %d", _worker_id); 138 } 139 140 void G1ConcurrentRefineThread::stop_service() { 141 MutexLockerEx x(_monitor, Mutex::_no_safepoint_check_flag); 142 _monitor->notify(); 143 }