1 /* 2 * Copyright (c) 2005, 2025, 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 "gc/parallel/objectStartArray.hpp" 26 #include "gc/parallel/parMarkBitMap.inline.hpp" 27 #include "gc/parallel/parallelScavengeHeap.hpp" 28 #include "gc/parallel/psCompactionManager.inline.hpp" 29 #include "gc/parallel/psOldGen.hpp" 30 #include "gc/parallel/psParallelCompact.inline.hpp" 31 #include "gc/shared/partialArraySplitter.inline.hpp" 32 #include "gc/shared/partialArrayState.hpp" 33 #include "gc/shared/preservedMarks.inline.hpp" 34 #include "gc/shared/taskqueue.inline.hpp" 35 #include "logging/log.hpp" 36 #include "memory/iterator.inline.hpp" 37 #include "oops/access.inline.hpp" 38 #include "oops/compressedOops.inline.hpp" 39 #include "oops/instanceKlass.inline.hpp" 40 #include "oops/instanceMirrorKlass.inline.hpp" 41 #include "oops/objArrayKlass.inline.hpp" 42 #include "oops/oop.inline.hpp" 43 44 PSOldGen* ParCompactionManager::_old_gen = nullptr; 45 ParCompactionManager** ParCompactionManager::_manager_array = nullptr; 46 47 ParCompactionManager::PSMarkTasksQueueSet* ParCompactionManager::_marking_stacks = nullptr; 48 ParCompactionManager::RegionTaskQueueSet* ParCompactionManager::_region_task_queues = nullptr; 49 PartialArrayStateManager* ParCompactionManager::_partial_array_state_manager = nullptr; 50 51 ObjectStartArray* ParCompactionManager::_start_array = nullptr; 52 ParMarkBitMap* ParCompactionManager::_mark_bitmap = nullptr; 53 GrowableArray<size_t >* ParCompactionManager::_shadow_region_array = nullptr; 54 Monitor* ParCompactionManager::_shadow_region_monitor = nullptr; 55 56 PreservedMarksSet* ParCompactionManager::_preserved_marks_set = nullptr; 57 58 ParCompactionManager::ParCompactionManager(PreservedMarks* preserved_marks, 59 ReferenceProcessor* ref_processor, 60 uint parallel_gc_threads) 61 :_partial_array_splitter(_partial_array_state_manager, parallel_gc_threads), 62 _mark_and_push_closure(this, ref_processor) { 63 64 ParallelScavengeHeap* heap = ParallelScavengeHeap::heap(); 65 66 _old_gen = heap->old_gen(); 67 _start_array = old_gen()->start_array(); 68 69 _preserved_marks = preserved_marks; 70 _marking_stats_cache = nullptr; 71 } 72 73 void ParCompactionManager::initialize(ParMarkBitMap* mbm) { 74 assert(ParallelScavengeHeap::heap() != nullptr, "Needed for initialization"); 75 assert(PSParallelCompact::ref_processor() != nullptr, "precondition"); 76 assert(ParallelScavengeHeap::heap()->workers().max_workers() != 0, "Not initialized?"); 77 78 _mark_bitmap = mbm; 79 80 uint parallel_gc_threads = ParallelScavengeHeap::heap()->workers().max_workers(); 81 82 assert(_manager_array == nullptr, "Attempt to initialize twice"); 83 _manager_array = NEW_C_HEAP_ARRAY(ParCompactionManager*, parallel_gc_threads, mtGC); 84 85 assert(_partial_array_state_manager == nullptr, "Attempt to initialize twice"); 86 _partial_array_state_manager 87 = new PartialArrayStateManager(parallel_gc_threads); 88 _marking_stacks = new PSMarkTasksQueueSet(parallel_gc_threads); 89 _region_task_queues = new RegionTaskQueueSet(parallel_gc_threads); 90 91 _preserved_marks_set = new PreservedMarksSet(true); 92 _preserved_marks_set->init(parallel_gc_threads); 93 94 // Create and register the ParCompactionManager(s) for the worker threads. 95 for(uint i=0; i<parallel_gc_threads; i++) { 96 _manager_array[i] = new ParCompactionManager(_preserved_marks_set->get(i), 97 PSParallelCompact::ref_processor(), 98 parallel_gc_threads); 99 marking_stacks()->register_queue(i, _manager_array[i]->marking_stack()); 100 region_task_queues()->register_queue(i, _manager_array[i]->region_stack()); 101 } 102 103 _shadow_region_array = new (mtGC) GrowableArray<size_t >(10, mtGC); 104 105 _shadow_region_monitor = new Monitor(Mutex::nosafepoint, "CompactionManager_lock"); 106 } 107 108 void ParCompactionManager::flush_all_string_dedup_requests() { 109 uint parallel_gc_threads = ParallelScavengeHeap::heap()->workers().max_workers(); 110 for (uint i=0; i<parallel_gc_threads; i++) { 111 _manager_array[i]->flush_string_dedup_requests(); 112 } 113 } 114 115 ParCompactionManager* 116 ParCompactionManager::gc_thread_compaction_manager(uint index) { 117 assert(index < ParallelGCThreads, "index out of range"); 118 assert(_manager_array != nullptr, "Sanity"); 119 return _manager_array[index]; 120 } 121 122 void ParCompactionManager::push_objArray(oop obj) { 123 assert(obj->is_objArray(), "precondition"); 124 _mark_and_push_closure.do_klass(obj->klass()); 125 126 objArrayOop obj_array = objArrayOop(obj); 127 size_t array_length = obj_array->length(); 128 size_t initial_chunk_size = 129 _partial_array_splitter.start(&_marking_stack, obj_array, nullptr, array_length); 130 follow_array(obj_array, 0, initial_chunk_size); 131 } 132 133 void ParCompactionManager::process_array_chunk(PartialArrayState* state, bool stolen) { 134 // Access before release by claim(). 135 oop obj = state->source(); 136 PartialArraySplitter::Claim claim = 137 _partial_array_splitter.claim(state, &_marking_stack, stolen); 138 follow_array(objArrayOop(obj), claim._start, claim._end); 139 } 140 141 void ParCompactionManager::follow_marking_stacks() { 142 ScannerTask task; 143 do { 144 // First, try to move tasks from the overflow stack into the shared buffer, so 145 // that other threads can steal. Otherwise process the overflow stack first. 146 while (marking_stack()->pop_overflow(task)) { 147 if (!marking_stack()->try_push_to_taskqueue(task)) { 148 follow_contents(task, false); 149 } 150 } 151 while (marking_stack()->pop_local(task)) { 152 follow_contents(task, false); 153 } 154 } while (!marking_stack_empty()); 155 156 assert(marking_stack_empty(), "Sanity"); 157 } 158 159 void ParCompactionManager::drain_region_stacks() { 160 do { 161 // Drain overflow stack first so other threads can steal. 162 size_t region_index; 163 while (region_stack()->pop_overflow(region_index)) { 164 PSParallelCompact::fill_and_update_region(this, region_index); 165 } 166 167 while (region_stack()->pop_local(region_index)) { 168 PSParallelCompact::fill_and_update_region(this, region_index); 169 } 170 } while (!region_stack()->is_empty()); 171 } 172 173 size_t ParCompactionManager::pop_shadow_region_mt_safe(PSParallelCompact::RegionData* region_ptr) { 174 MonitorLocker ml(_shadow_region_monitor, Mutex::_no_safepoint_check_flag); 175 while (true) { 176 if (!_shadow_region_array->is_empty()) { 177 return _shadow_region_array->pop(); 178 } 179 // Check if the corresponding heap region is available now. 180 // If so, we don't need to get a shadow region anymore, and 181 // we return InvalidShadow to indicate such a case. 182 if (region_ptr->claimed()) { 183 return InvalidShadow; 184 } 185 ml.wait(1); 186 } 187 } 188 189 void ParCompactionManager::push_shadow_region_mt_safe(size_t shadow_region) { 190 MonitorLocker ml(_shadow_region_monitor, Mutex::_no_safepoint_check_flag); 191 _shadow_region_array->push(shadow_region); 192 ml.notify(); 193 } 194 195 void ParCompactionManager::push_shadow_region(size_t shadow_region) { 196 _shadow_region_array->push(shadow_region); 197 } 198 199 void ParCompactionManager::remove_all_shadow_regions() { 200 _shadow_region_array->clear(); 201 } 202 203 204 #if TASKQUEUE_STATS 205 void ParCompactionManager::print_and_reset_taskqueue_stats() { 206 marking_stacks()->print_and_reset_taskqueue_stats("Marking Stacks"); 207 208 auto get_pa_stats = [&](uint i) { 209 return _manager_array[i]->partial_array_task_stats(); 210 }; 211 PartialArrayTaskStats::log_set(ParallelGCThreads, get_pa_stats, 212 "Partial Array Task Stats"); 213 uint parallel_gc_threads = ParallelScavengeHeap::heap()->workers().max_workers(); 214 for (uint i = 0; i < parallel_gc_threads; ++i) { 215 get_pa_stats(i)->reset(); 216 } 217 } 218 219 PartialArrayTaskStats* ParCompactionManager::partial_array_task_stats() { 220 return _partial_array_splitter.stats(); 221 } 222 #endif // TASKQUEUE_STATS 223 224 #ifdef ASSERT 225 void ParCompactionManager::verify_all_marking_stack_empty() { 226 uint parallel_gc_threads = ParallelGCThreads; 227 for (uint i = 0; i < parallel_gc_threads; i++) { 228 assert(_manager_array[i]->marking_stack_empty(), "Marking stack should be empty"); 229 } 230 } 231 232 void ParCompactionManager::verify_all_region_stack_empty() { 233 uint parallel_gc_threads = ParallelGCThreads; 234 for (uint i = 0; i < parallel_gc_threads; i++) { 235 assert(_manager_array[i]->region_stack()->is_empty(), "Region stack should be empty"); 236 } 237 } 238 #endif --- EOF ---