1 /* 2 * Copyright (c) 2005, 2021, 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/parallel/objectStartArray.hpp" 27 #include "gc/parallel/parMarkBitMap.inline.hpp" 28 #include "gc/parallel/parallelScavengeHeap.hpp" 29 #include "gc/parallel/psCompactionManager.inline.hpp" 30 #include "gc/parallel/psOldGen.hpp" 31 #include "gc/parallel/psParallelCompact.inline.hpp" 32 #include "gc/shared/taskqueue.inline.hpp" 33 #include "logging/log.hpp" 34 #include "memory/iterator.inline.hpp" 35 #include "oops/access.inline.hpp" 36 #include "oops/compressedOops.inline.hpp" 37 #include "oops/instanceKlass.inline.hpp" 38 #include "oops/instanceMirrorKlass.inline.hpp" 39 #include "oops/objArrayKlass.inline.hpp" 40 #include "oops/oop.inline.hpp" 41 42 PSOldGen* ParCompactionManager::_old_gen = NULL; 43 ParCompactionManager** ParCompactionManager::_manager_array = NULL; 44 45 ParCompactionManager::OopTaskQueueSet* ParCompactionManager::_oop_task_queues = NULL; 46 ParCompactionManager::ObjArrayTaskQueueSet* ParCompactionManager::_objarray_task_queues = NULL; 47 ParCompactionManager::RegionTaskQueueSet* ParCompactionManager::_region_task_queues = NULL; 48 49 ObjectStartArray* ParCompactionManager::_start_array = NULL; 50 ParMarkBitMap* ParCompactionManager::_mark_bitmap = NULL; 51 GrowableArray<size_t >* ParCompactionManager::_shadow_region_array = NULL; 52 Monitor* ParCompactionManager::_shadow_region_monitor = NULL; 53 54 ParCompactionManager::ParCompactionManager() { 55 56 ParallelScavengeHeap* heap = ParallelScavengeHeap::heap(); 57 58 _old_gen = heap->old_gen(); 59 _start_array = old_gen()->start_array(); 60 61 reset_bitmap_query_cache(); 62 } 63 64 void ParCompactionManager::initialize(ParMarkBitMap* mbm) { 65 assert(ParallelScavengeHeap::heap() != NULL, 66 "Needed for initialization"); 67 68 _mark_bitmap = mbm; 69 70 uint parallel_gc_threads = ParallelScavengeHeap::heap()->workers().max_workers(); 71 72 assert(_manager_array == NULL, "Attempt to initialize twice"); 73 _manager_array = NEW_C_HEAP_ARRAY(ParCompactionManager*, parallel_gc_threads, mtGC); 74 75 _oop_task_queues = new OopTaskQueueSet(parallel_gc_threads); 76 _objarray_task_queues = new ObjArrayTaskQueueSet(parallel_gc_threads); 77 _region_task_queues = new RegionTaskQueueSet(parallel_gc_threads); 78 79 // Create and register the ParCompactionManager(s) for the worker threads. 80 for(uint i=0; i<parallel_gc_threads; i++) { 81 _manager_array[i] = new ParCompactionManager(); 82 oop_task_queues()->register_queue(i, _manager_array[i]->marking_stack()); 83 _objarray_task_queues->register_queue(i, &_manager_array[i]->_objarray_stack); 84 region_task_queues()->register_queue(i, _manager_array[i]->region_stack()); 85 } 86 87 assert(ParallelScavengeHeap::heap()->workers().max_workers() != 0, 88 "Not initialized?"); 89 90 _shadow_region_array = new (ResourceObj::C_HEAP, mtGC) GrowableArray<size_t >(10, mtGC); 91 92 _shadow_region_monitor = new Monitor(Mutex::nosafepoint, "CompactionManager_lock"); 93 } 94 95 void ParCompactionManager::reset_all_bitmap_query_caches() { 96 uint parallel_gc_threads = ParallelScavengeHeap::heap()->workers().max_workers(); 97 for (uint i=0; i<parallel_gc_threads; i++) { 98 _manager_array[i]->reset_bitmap_query_cache(); 99 } 100 } 101 102 void ParCompactionManager::flush_all_string_dedup_requests() { 103 uint parallel_gc_threads = ParallelScavengeHeap::heap()->workers().max_workers(); 104 for (uint i=0; i<parallel_gc_threads; i++) { 105 _manager_array[i]->flush_string_dedup_requests(); 106 } 107 } 108 109 ParCompactionManager* 110 ParCompactionManager::gc_thread_compaction_manager(uint index) { 111 assert(index < ParallelGCThreads, "index out of range"); 112 assert(_manager_array != NULL, "Sanity"); 113 return _manager_array[index]; 114 } 115 116 inline void ParCompactionManager::publish_and_drain_oop_tasks() { 117 oop obj; 118 while (marking_stack()->pop_overflow(obj)) { 119 if (!marking_stack()->try_push_to_taskqueue(obj)) { 120 follow_contents(obj); 121 } 122 } 123 while (marking_stack()->pop_local(obj)) { 124 follow_contents(obj); 125 } 126 } 127 128 bool ParCompactionManager::publish_or_pop_objarray_tasks(ObjArrayTask& task) { 129 while (_objarray_stack.pop_overflow(task)) { 130 if (!_objarray_stack.try_push_to_taskqueue(task)) { 131 return true; 132 } 133 } 134 return false; 135 } 136 137 void ParCompactionManager::follow_marking_stacks() { 138 do { 139 // First, try to move tasks from the overflow stack into the shared buffer, so 140 // that other threads can steal. Otherwise process the overflow stack first. 141 publish_and_drain_oop_tasks(); 142 143 // Process ObjArrays one at a time to avoid marking stack bloat. 144 ObjArrayTask task; 145 if (publish_or_pop_objarray_tasks(task) || 146 _objarray_stack.pop_local(task)) { 147 follow_array((objArrayOop)task.obj(), task.index()); 148 } 149 } while (!marking_stacks_empty()); 150 151 assert(marking_stacks_empty(), "Sanity"); 152 } 153 154 void ParCompactionManager::drain_region_stacks() { 155 do { 156 // Drain overflow stack first so other threads can steal. 157 size_t region_index; 158 while (region_stack()->pop_overflow(region_index)) { 159 PSParallelCompact::fill_and_update_region(this, region_index); 160 } 161 162 while (region_stack()->pop_local(region_index)) { 163 PSParallelCompact::fill_and_update_region(this, region_index); 164 } 165 } while (!region_stack()->is_empty()); 166 } 167 168 size_t ParCompactionManager::pop_shadow_region_mt_safe(PSParallelCompact::RegionData* region_ptr) { 169 MonitorLocker ml(_shadow_region_monitor, Mutex::_no_safepoint_check_flag); 170 while (true) { 171 if (!_shadow_region_array->is_empty()) { 172 return _shadow_region_array->pop(); 173 } 174 // Check if the corresponding heap region is available now. 175 // If so, we don't need to get a shadow region anymore, and 176 // we return InvalidShadow to indicate such a case. 177 if (region_ptr->claimed()) { 178 return InvalidShadow; 179 } 180 ml.wait(1); 181 } 182 } 183 184 void ParCompactionManager::push_shadow_region_mt_safe(size_t shadow_region) { 185 MonitorLocker ml(_shadow_region_monitor, Mutex::_no_safepoint_check_flag); 186 _shadow_region_array->push(shadow_region); 187 ml.notify(); 188 } 189 190 void ParCompactionManager::push_shadow_region(size_t shadow_region) { 191 _shadow_region_array->push(shadow_region); 192 } 193 194 void ParCompactionManager::remove_all_shadow_regions() { 195 _shadow_region_array->clear(); 196 } 197 198 #ifdef ASSERT 199 void ParCompactionManager::verify_all_marking_stack_empty() { 200 uint parallel_gc_threads = ParallelGCThreads; 201 for (uint i = 0; i < parallel_gc_threads; i++) { 202 assert(_manager_array[i]->marking_stacks_empty(), "Marking stack should be empty"); 203 } 204 } 205 206 void ParCompactionManager::verify_all_region_stack_empty() { 207 uint parallel_gc_threads = ParallelGCThreads; 208 for (uint i = 0; i < parallel_gc_threads; i++) { 209 assert(_manager_array[i]->region_stack()->is_empty(), "Region stack should be empty"); 210 } 211 } 212 #endif