1 /*
2 * Copyright (c) 2005, 2010, 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_implementation/parallelScavenge/gcTaskManager.hpp"
28 #include "gc_implementation/parallelScavenge/objectStartArray.hpp"
29 #include "gc_implementation/parallelScavenge/parMarkBitMap.hpp"
30 #include "gc_implementation/parallelScavenge/parallelScavengeHeap.hpp"
31 #include "gc_implementation/parallelScavenge/psCompactionManager.hpp"
32 #include "gc_implementation/parallelScavenge/psOldGen.hpp"
33 #include "gc_implementation/parallelScavenge/psParallelCompact.hpp"
34 #include "oops/objArrayKlass.inline.hpp"
35 #include "oops/oop.hpp"
36 #include "oops/oop.inline.hpp"
37 #include "oops/oop.pcgc.inline.hpp"
38
39 PSOldGen* ParCompactionManager::_old_gen = NULL;
40 ParCompactionManager** ParCompactionManager::_manager_array = NULL;
41 OopTaskQueueSet* ParCompactionManager::_stack_array = NULL;
42 ParCompactionManager::ObjArrayTaskQueueSet*
43 ParCompactionManager::_objarray_queues = NULL;
44 ObjectStartArray* ParCompactionManager::_start_array = NULL;
45 ParMarkBitMap* ParCompactionManager::_mark_bitmap = NULL;
46 RegionTaskQueueSet* ParCompactionManager::_region_array = NULL;
47
48 ParCompactionManager::ParCompactionManager() :
49 _action(CopyAndUpdate) {
50
51 ParallelScavengeHeap* heap = (ParallelScavengeHeap*)Universe::heap();
52 assert(heap->kind() == CollectedHeap::ParallelScavengeHeap, "Sanity");
53
54 _old_gen = heap->old_gen();
55 _start_array = old_gen()->start_array();
56
57 marking_stack()->initialize();
58 _objarray_stack.initialize();
59 region_stack()->initialize();
60
61 // Note that _revisit_klass_stack is allocated out of the
62 // C heap (as opposed to out of ResourceArena).
63 int size =
64 (SystemDictionary::number_of_classes() * 2) * 2 / ParallelGCThreads;
65 _revisit_klass_stack = new (ResourceObj::C_HEAP) GrowableArray<Klass*>(size, true);
66 // From some experiments (#klass/k)^2 for k = 10 seems a better fit, but this will
67 // have to do for now until we are able to investigate a more optimal setting.
68 _revisit_mdo_stack = new (ResourceObj::C_HEAP) GrowableArray<DataLayout*>(size*2, true);
69 }
70
71 ParCompactionManager::~ParCompactionManager() {
72 delete _revisit_klass_stack;
73 delete _revisit_mdo_stack;
74 // _manager_array and _stack_array are statics
75 // shared with all instances of ParCompactionManager
76 // should not be deallocated.
77 }
78
79 void ParCompactionManager::initialize(ParMarkBitMap* mbm) {
80 assert(PSParallelCompact::gc_task_manager() != NULL,
81 "Needed for initialization");
82
83 _mark_bitmap = mbm;
84
85 uint parallel_gc_threads = PSParallelCompact::gc_task_manager()->workers();
86
87 assert(_manager_array == NULL, "Attempt to initialize twice");
88 _manager_array = NEW_C_HEAP_ARRAY(ParCompactionManager*, parallel_gc_threads+1 );
89 guarantee(_manager_array != NULL, "Could not allocate manager_array");
90
91 _stack_array = new OopTaskQueueSet(parallel_gc_threads);
92 guarantee(_stack_array != NULL, "Could not allocate stack_array");
93 _objarray_queues = new ObjArrayTaskQueueSet(parallel_gc_threads);
94 guarantee(_objarray_queues != NULL, "Could not allocate objarray_queues");
95 _region_array = new RegionTaskQueueSet(parallel_gc_threads);
96 guarantee(_region_array != NULL, "Could not allocate region_array");
97
98 // Create and register the ParCompactionManager(s) for the worker threads.
99 for(uint i=0; i<parallel_gc_threads; i++) {
100 _manager_array[i] = new ParCompactionManager();
101 guarantee(_manager_array[i] != NULL, "Could not create ParCompactionManager");
102 stack_array()->register_queue(i, _manager_array[i]->marking_stack());
103 _objarray_queues->register_queue(i, &_manager_array[i]->_objarray_stack);
104 region_array()->register_queue(i, _manager_array[i]->region_stack());
105 }
106
107 // The VMThread gets its own ParCompactionManager, which is not available
108 // for work stealing.
109 _manager_array[parallel_gc_threads] = new ParCompactionManager();
110 guarantee(_manager_array[parallel_gc_threads] != NULL,
111 "Could not create ParCompactionManager");
112 assert(PSParallelCompact::gc_task_manager()->workers() != 0,
113 "Not initialized?");
114 }
115
116 bool ParCompactionManager::should_update() {
117 assert(action() != NotValid, "Action is not set");
118 return (action() == ParCompactionManager::Update) ||
119 (action() == ParCompactionManager::CopyAndUpdate) ||
120 (action() == ParCompactionManager::UpdateAndCopy);
121 }
122
123 bool ParCompactionManager::should_copy() {
124 assert(action() != NotValid, "Action is not set");
125 return (action() == ParCompactionManager::Copy) ||
126 (action() == ParCompactionManager::CopyAndUpdate) ||
127 (action() == ParCompactionManager::UpdateAndCopy);
128 }
129
130 bool ParCompactionManager::should_verify_only() {
131 assert(action() != NotValid, "Action is not set");
132 return action() == ParCompactionManager::VerifyUpdate;
133 }
134
135 bool ParCompactionManager::should_reset_only() {
136 assert(action() != NotValid, "Action is not set");
137 return action() == ParCompactionManager::ResetObjects;
138 }
139
140 ParCompactionManager*
141 ParCompactionManager::gc_thread_compaction_manager(int index) {
142 assert(index >= 0 && index < (int)ParallelGCThreads, "index out of range");
143 assert(_manager_array != NULL, "Sanity");
144 return _manager_array[index];
145 }
146
147 void ParCompactionManager::reset() {
148 for(uint i=0; i<ParallelGCThreads+1; i++) {
149 manager_array(i)->revisit_klass_stack()->clear();
150 manager_array(i)->revisit_mdo_stack()->clear();
151 }
152 }
153
154 void ParCompactionManager::follow_marking_stacks() {
155 do {
156 // Drain the overflow stack first, to allow stealing from the marking stack.
157 oop obj;
158 while (marking_stack()->pop_overflow(obj)) {
159 obj->follow_contents(this);
160 }
161 while (marking_stack()->pop_local(obj)) {
162 obj->follow_contents(this);
163 }
164
165 // Process ObjArrays one at a time to avoid marking stack bloat.
166 ObjArrayTask task;
167 if (_objarray_stack.pop_overflow(task)) {
168 objArrayKlass* const k = (objArrayKlass*)task.obj()->blueprint();
169 k->oop_follow_contents(this, task.obj(), task.index());
170 } else if (_objarray_stack.pop_local(task)) {
171 objArrayKlass* const k = (objArrayKlass*)task.obj()->blueprint();
172 k->oop_follow_contents(this, task.obj(), task.index());
173 }
174 } while (!marking_stacks_empty());
175
176 assert(marking_stacks_empty(), "Sanity");
177 }
178
179 void ParCompactionManager::drain_region_stacks() {
180 do {
181 // Drain overflow stack first so other threads can steal.
182 size_t region_index;
183 while (region_stack()->pop_overflow(region_index)) {
184 PSParallelCompact::fill_and_update_region(this, region_index);
185 }
186
187 while (region_stack()->pop_local(region_index)) {
188 PSParallelCompact::fill_and_update_region(this, region_index);
189 }
190 } while (!region_stack()->is_empty());
191 }
192
193 #ifdef ASSERT
194 bool ParCompactionManager::stacks_have_been_allocated() {
195 return (revisit_klass_stack()->data_addr() != NULL &&
196 revisit_mdo_stack()->data_addr() != NULL);
197 }
198 #endif