1 /* 2 * Copyright (c) 2005, 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 "classfile/systemDictionary.hpp" 27 #include "gc/parallel/objectStartArray.hpp" 28 #include "gc/parallel/parMarkBitMap.inline.hpp" 29 #include "gc/parallel/parallelScavengeHeap.hpp" 30 #include "gc/parallel/psCompactionManager.inline.hpp" 31 #include "gc/parallel/psOldGen.hpp" 32 #include "gc/parallel/psParallelCompact.inline.hpp" 33 #include "gc/shared/taskqueue.inline.hpp" 34 #include "logging/log.hpp" 35 #include "memory/iterator.inline.hpp" 36 #include "oops/access.inline.hpp" 37 #include "oops/compressedOops.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 OopTaskQueueSet* ParCompactionManager::_stack_array = NULL; 47 ParCompactionManager::ObjArrayTaskQueueSet* 48 ParCompactionManager::_objarray_queues = NULL; 49 ObjectStartArray* ParCompactionManager::_start_array = NULL; 50 ParMarkBitMap* ParCompactionManager::_mark_bitmap = NULL; 51 RegionTaskQueueSet* ParCompactionManager::_region_array = NULL; 52 GrowableArray<size_t >* ParCompactionManager::_shadow_region_array = NULL; 53 Monitor* ParCompactionManager::_shadow_region_monitor = NULL; 54 55 ParCompactionManager::ParCompactionManager() : 56 _action(CopyAndUpdate) { 57 58 ParallelScavengeHeap* heap = ParallelScavengeHeap::heap(); 59 60 _old_gen = heap->old_gen(); 61 _start_array = old_gen()->start_array(); 62 63 marking_stack()->initialize(); 64 _objarray_stack.initialize(); 65 _region_stack.initialize(); 66 67 reset_bitmap_query_cache(); 68 } 69 70 void ParCompactionManager::initialize(ParMarkBitMap* mbm) { 71 assert(ParallelScavengeHeap::heap() != NULL, 72 "Needed for initialization"); 73 74 _mark_bitmap = mbm; 75 76 uint parallel_gc_threads = ParallelScavengeHeap::heap()->workers().total_workers(); 77 78 assert(_manager_array == NULL, "Attempt to initialize twice"); 79 _manager_array = NEW_C_HEAP_ARRAY(ParCompactionManager*, parallel_gc_threads+1, mtGC); 80 81 _stack_array = new OopTaskQueueSet(parallel_gc_threads); 82 guarantee(_stack_array != NULL, "Could not allocate stack_array"); 83 _objarray_queues = new ObjArrayTaskQueueSet(parallel_gc_threads); 84 guarantee(_objarray_queues != NULL, "Could not allocate objarray_queues"); 85 _region_array = new RegionTaskQueueSet(parallel_gc_threads); 86 guarantee(_region_array != NULL, "Could not allocate region_array"); 87 88 // Create and register the ParCompactionManager(s) for the worker threads. 89 for(uint i=0; i<parallel_gc_threads; i++) { 90 _manager_array[i] = new ParCompactionManager(); 91 guarantee(_manager_array[i] != NULL, "Could not create ParCompactionManager"); 92 stack_array()->register_queue(i, _manager_array[i]->marking_stack()); 93 _objarray_queues->register_queue(i, &_manager_array[i]->_objarray_stack); 94 region_array()->register_queue(i, _manager_array[i]->region_stack()); 95 } 96 97 // The VMThread gets its own ParCompactionManager, which is not available 98 // for work stealing. 99 _manager_array[parallel_gc_threads] = new ParCompactionManager(); 100 guarantee(_manager_array[parallel_gc_threads] != NULL, 101 "Could not create ParCompactionManager"); 102 assert(ParallelScavengeHeap::heap()->workers().total_workers() != 0, 103 "Not initialized?"); 104 105 _shadow_region_array = new (ResourceObj::C_HEAP, mtInternal) GrowableArray<size_t >(10, true); 106 107 _shadow_region_monitor = new Monitor(Mutex::barrier, "CompactionManager monitor", 108 Mutex::_allow_vm_block_flag, Monitor::_safepoint_check_never); 109 } 110 111 void ParCompactionManager::reset_all_bitmap_query_caches() { 112 uint parallel_gc_threads = ParallelScavengeHeap::heap()->workers().total_workers(); 113 for (uint i=0; i<=parallel_gc_threads; i++) { 114 _manager_array[i]->reset_bitmap_query_cache(); 115 } 116 } 117 118 bool ParCompactionManager::should_update() { 119 assert(action() != NotValid, "Action is not set"); 120 return (action() == ParCompactionManager::Update) || 121 (action() == ParCompactionManager::CopyAndUpdate) || 122 (action() == ParCompactionManager::UpdateAndCopy); 123 } 124 125 bool ParCompactionManager::should_copy() { 126 assert(action() != NotValid, "Action is not set"); 127 return (action() == ParCompactionManager::Copy) || 128 (action() == ParCompactionManager::CopyAndUpdate) || 129 (action() == ParCompactionManager::UpdateAndCopy); 130 } 131 132 ParCompactionManager* 133 ParCompactionManager::gc_thread_compaction_manager(uint index) { 134 assert(index < ParallelGCThreads, "index out of range"); 135 assert(_manager_array != NULL, "Sanity"); 136 return _manager_array[index]; 137 } 138 139 void ParCompactionManager::follow_marking_stacks() { 140 do { 141 // Drain the overflow stack first, to allow stealing from the marking stack. 142 oop obj; 143 while (marking_stack()->pop_overflow(obj)) { 144 follow_contents(obj); 145 } 146 while (marking_stack()->pop_local(obj)) { 147 follow_contents(obj); 148 } 149 150 // Process ObjArrays one at a time to avoid marking stack bloat. 151 ObjArrayTask task; 152 if (_objarray_stack.pop_overflow(task) || _objarray_stack.pop_local(task)) { 153 follow_array((objArrayOop)task.obj(), task.index()); 154 } 155 } while (!marking_stacks_empty()); 156 157 assert(marking_stacks_empty(), "Sanity"); 158 } 159 160 void ParCompactionManager::drain_region_stacks() { 161 do { 162 // Drain overflow stack first so other threads can steal. 163 size_t region_index; 164 while (region_stack()->pop_overflow(region_index)) { 165 PSParallelCompact::fill_and_update_region(this, region_index); 166 } 167 168 while (region_stack()->pop_local(region_index)) { 169 PSParallelCompact::fill_and_update_region(this, region_index); 170 } 171 } while (!region_stack()->is_empty()); 172 } 173 174 size_t ParCompactionManager::pop_shadow_region_mt_safe(PSParallelCompact::RegionData* region_ptr) { 175 MonitorLocker ml(_shadow_region_monitor, Mutex::_no_safepoint_check_flag); 176 while (true) { 177 if (!_shadow_region_array->is_empty()) { 178 return _shadow_region_array->pop(); 179 } 180 // Check if the corresponding heap region is available now. 181 // If so, we don't need to get a shadow region anymore, and 182 // we return InvalidShadow to indicate such a case. 183 if (region_ptr->claimed()) { 184 return InvalidShadow; 185 } 186 ml.wait(1); 187 } 188 } 189 190 void ParCompactionManager::push_shadow_region_mt_safe(size_t shadow_region) { 191 MonitorLocker ml(_shadow_region_monitor, Mutex::_no_safepoint_check_flag); 192 _shadow_region_array->push(shadow_region); 193 ml.notify(); 194 } 195 196 void ParCompactionManager::push_shadow_region(size_t shadow_region) { 197 _shadow_region_array->push(shadow_region); 198 } 199 200 void ParCompactionManager::remove_all_shadow_regions() { 201 _shadow_region_array->clear(); 202 }