1 /* 2 * Copyright (c) 2005, 2022, 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/flatArrayKlass.inline.hpp" 38 #include "oops/instanceKlass.inline.hpp" 39 #include "oops/instanceMirrorKlass.inline.hpp" 40 #include "oops/objArrayKlass.inline.hpp" 41 #include "oops/oop.inline.hpp" 42 43 PSOldGen* ParCompactionManager::_old_gen = NULL; 44 ParCompactionManager** ParCompactionManager::_manager_array = NULL; 45 46 ParCompactionManager::OopTaskQueueSet* ParCompactionManager::_oop_task_queues = NULL; 47 ParCompactionManager::ObjArrayTaskQueueSet* ParCompactionManager::_objarray_task_queues = NULL; 48 ParCompactionManager::RegionTaskQueueSet* ParCompactionManager::_region_task_queues = NULL; 49 50 ObjectStartArray* ParCompactionManager::_start_array = NULL; 51 ParMarkBitMap* ParCompactionManager::_mark_bitmap = NULL; 52 GrowableArray<size_t >* ParCompactionManager::_shadow_region_array = NULL; 53 Monitor* ParCompactionManager::_shadow_region_monitor = NULL; 54 55 ParCompactionManager::ParCompactionManager() { 56 57 ParallelScavengeHeap* heap = ParallelScavengeHeap::heap(); 58 59 _old_gen = heap->old_gen(); 60 _start_array = old_gen()->start_array(); 61 62 reset_bitmap_query_cache(); 63 64 _deferred_obj_array = new (mtGC) GrowableArray<HeapWord*>(10, mtGC); 65 } 66 67 void ParCompactionManager::initialize(ParMarkBitMap* mbm) { 68 assert(ParallelScavengeHeap::heap() != NULL, 69 "Needed for initialization"); 70 71 _mark_bitmap = mbm; 72 73 uint parallel_gc_threads = ParallelScavengeHeap::heap()->workers().max_workers(); 74 75 assert(_manager_array == NULL, "Attempt to initialize twice"); 76 _manager_array = NEW_C_HEAP_ARRAY(ParCompactionManager*, parallel_gc_threads, mtGC); 77 78 _oop_task_queues = new OopTaskQueueSet(parallel_gc_threads); 79 _objarray_task_queues = new ObjArrayTaskQueueSet(parallel_gc_threads); 80 _region_task_queues = new RegionTaskQueueSet(parallel_gc_threads); 81 82 // Create and register the ParCompactionManager(s) for the worker threads. 83 for(uint i=0; i<parallel_gc_threads; i++) { 84 _manager_array[i] = new ParCompactionManager(); 85 oop_task_queues()->register_queue(i, _manager_array[i]->marking_stack()); 86 _objarray_task_queues->register_queue(i, &_manager_array[i]->_objarray_stack); 87 region_task_queues()->register_queue(i, _manager_array[i]->region_stack()); 88 } 89 90 assert(ParallelScavengeHeap::heap()->workers().max_workers() != 0, 91 "Not initialized?"); 92 93 _shadow_region_array = new (mtGC) GrowableArray<size_t >(10, mtGC); 94 95 _shadow_region_monitor = new Monitor(Mutex::nosafepoint, "CompactionManager_lock"); 96 } 97 98 void ParCompactionManager::reset_all_bitmap_query_caches() { 99 uint parallel_gc_threads = ParallelScavengeHeap::heap()->workers().max_workers(); 100 for (uint i=0; i<parallel_gc_threads; i++) { 101 _manager_array[i]->reset_bitmap_query_cache(); 102 } 103 } 104 105 void ParCompactionManager::flush_all_string_dedup_requests() { 106 uint parallel_gc_threads = ParallelScavengeHeap::heap()->workers().max_workers(); 107 for (uint i=0; i<parallel_gc_threads; i++) { 108 _manager_array[i]->flush_string_dedup_requests(); 109 } 110 } 111 112 ParCompactionManager* 113 ParCompactionManager::gc_thread_compaction_manager(uint index) { 114 assert(index < ParallelGCThreads, "index out of range"); 115 assert(_manager_array != NULL, "Sanity"); 116 return _manager_array[index]; 117 } 118 119 inline void ParCompactionManager::publish_and_drain_oop_tasks() { 120 oop obj; 121 while (marking_stack()->pop_overflow(obj)) { 122 if (!marking_stack()->try_push_to_taskqueue(obj)) { 123 follow_contents(obj); 124 } 125 } 126 while (marking_stack()->pop_local(obj)) { 127 follow_contents(obj); 128 } 129 } 130 131 bool ParCompactionManager::publish_or_pop_objarray_tasks(ObjArrayTask& task) { 132 while (_objarray_stack.pop_overflow(task)) { 133 if (!_objarray_stack.try_push_to_taskqueue(task)) { 134 return true; 135 } 136 } 137 return false; 138 } 139 140 void ParCompactionManager::follow_marking_stacks() { 141 do { 142 // First, try to move tasks from the overflow stack into the shared buffer, so 143 // that other threads can steal. Otherwise process the overflow stack first. 144 publish_and_drain_oop_tasks(); 145 146 // Process ObjArrays one at a time to avoid marking stack bloat. 147 ObjArrayTask task; 148 if (publish_or_pop_objarray_tasks(task) || 149 _objarray_stack.pop_local(task)) { 150 follow_array((objArrayOop)task.obj(), task.index()); 151 } 152 } while (!marking_stacks_empty()); 153 154 assert(marking_stacks_empty(), "Sanity"); 155 } 156 157 void ParCompactionManager::drain_region_stacks() { 158 do { 159 // Drain overflow stack first so other threads can steal. 160 size_t region_index; 161 while (region_stack()->pop_overflow(region_index)) { 162 PSParallelCompact::fill_and_update_region(this, region_index); 163 } 164 165 while (region_stack()->pop_local(region_index)) { 166 PSParallelCompact::fill_and_update_region(this, region_index); 167 } 168 } while (!region_stack()->is_empty()); 169 } 170 171 void ParCompactionManager::drain_deferred_objects() { 172 while (!_deferred_obj_array->is_empty()) { 173 HeapWord* addr = _deferred_obj_array->pop(); 174 assert(addr != NULL, "expected a deferred object"); 175 PSParallelCompact::update_deferred_object(this, addr); 176 } 177 _deferred_obj_array->clear_and_deallocate(); 178 } 179 180 size_t ParCompactionManager::pop_shadow_region_mt_safe(PSParallelCompact::RegionData* region_ptr) { 181 MonitorLocker ml(_shadow_region_monitor, Mutex::_no_safepoint_check_flag); 182 while (true) { 183 if (!_shadow_region_array->is_empty()) { 184 return _shadow_region_array->pop(); 185 } 186 // Check if the corresponding heap region is available now. 187 // If so, we don't need to get a shadow region anymore, and 188 // we return InvalidShadow to indicate such a case. 189 if (region_ptr->claimed()) { 190 return InvalidShadow; 191 } 192 ml.wait(1); 193 } 194 } 195 196 void ParCompactionManager::push_shadow_region_mt_safe(size_t shadow_region) { 197 MonitorLocker ml(_shadow_region_monitor, Mutex::_no_safepoint_check_flag); 198 _shadow_region_array->push(shadow_region); 199 ml.notify(); 200 } 201 202 void ParCompactionManager::push_shadow_region(size_t shadow_region) { 203 _shadow_region_array->push(shadow_region); 204 } 205 206 void ParCompactionManager::remove_all_shadow_regions() { 207 _shadow_region_array->clear(); 208 } 209 210 void ParCompactionManager::push_deferred_object(HeapWord* addr) { 211 _deferred_obj_array->push(addr); 212 } 213 214 #ifdef ASSERT 215 void ParCompactionManager::verify_all_marking_stack_empty() { 216 uint parallel_gc_threads = ParallelGCThreads; 217 for (uint i = 0; i < parallel_gc_threads; i++) { 218 assert(_manager_array[i]->marking_stacks_empty(), "Marking stack should be empty"); 219 } 220 } 221 222 void ParCompactionManager::verify_all_region_stack_empty() { 223 uint parallel_gc_threads = ParallelGCThreads; 224 for (uint i = 0; i < parallel_gc_threads; i++) { 225 assert(_manager_array[i]->region_stack()->is_empty(), "Region stack should be empty"); 226 } 227 } 228 #endif