1 /*
2 * Copyright (c) 2005, 2013, 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.inline.hpp"
36 #include "oops/oop.pcgc.inline.hpp"
37 #include "runtime/atomic.inline.hpp"
38 #include "utilities/stack.inline.hpp"
39
40 PSOldGen* ParCompactionManager::_old_gen = NULL;
41 ParCompactionManager** ParCompactionManager::_manager_array = NULL;
42
43 RegionTaskQueue** ParCompactionManager::_region_list = NULL;
44
45 OopTaskQueueSet* ParCompactionManager::_stack_array = NULL;
46 ParCompactionManager::ObjArrayTaskQueueSet*
47 ParCompactionManager::_objarray_queues = NULL;
48 ObjectStartArray* ParCompactionManager::_start_array = NULL;
49 ParMarkBitMap* ParCompactionManager::_mark_bitmap = NULL;
50 RegionTaskQueueSet* ParCompactionManager::_region_array = NULL;
51
52 uint* ParCompactionManager::_recycled_stack_index = NULL;
53 int ParCompactionManager::_recycled_top = -1;
54 int ParCompactionManager::_recycled_bottom = -1;
55
56 ParCompactionManager::ParCompactionManager() :
57 _action(CopyAndUpdate),
58 _region_stack(NULL),
59 _region_stack_index((uint)max_uintx) {
60
61 ParallelScavengeHeap* heap = (ParallelScavengeHeap*)Universe::heap();
62 assert(heap->kind() == CollectedHeap::ParallelScavengeHeap, "Sanity");
63
64 _old_gen = heap->old_gen();
65 _start_array = old_gen()->start_array();
66
67 marking_stack()->initialize();
68 _objarray_stack.initialize();
69 }
70
71 ParCompactionManager::~ParCompactionManager() {
72 delete _recycled_stack_index;
73 }
74
75 void ParCompactionManager::initialize(ParMarkBitMap* mbm) {
76 assert(PSParallelCompact::gc_task_manager() != NULL,
77 "Needed for initialization");
78
79 _mark_bitmap = mbm;
80
81 uint parallel_gc_threads = PSParallelCompact::gc_task_manager()->workers();
82
83 assert(_manager_array == NULL, "Attempt to initialize twice");
84 _manager_array = NEW_C_HEAP_ARRAY(ParCompactionManager*, parallel_gc_threads+1, mtGC);
85 guarantee(_manager_array != NULL, "Could not allocate manager_array");
86
87 _region_list = NEW_C_HEAP_ARRAY(RegionTaskQueue*,
88 parallel_gc_threads+1, mtGC);
89 guarantee(_region_list != NULL, "Could not initialize promotion manager");
90
91 _recycled_stack_index = NEW_C_HEAP_ARRAY(uint, parallel_gc_threads, mtGC);
92
93 // parallel_gc-threads + 1 to be consistent with the number of
94 // compaction managers.
95 for(uint i=0; i<parallel_gc_threads + 1; i++) {
96 _region_list[i] = new RegionTaskQueue();
97 region_list(i)->initialize();
98 }
99
100 _stack_array = new OopTaskQueueSet(parallel_gc_threads);
101 guarantee(_stack_array != NULL, "Could not allocate stack_array");
102 _objarray_queues = new ObjArrayTaskQueueSet(parallel_gc_threads);
103 guarantee(_objarray_queues != NULL, "Could not allocate objarray_queues");
104 _region_array = new RegionTaskQueueSet(parallel_gc_threads);
105 guarantee(_region_array != NULL, "Could not allocate region_array");
106
107 // Create and register the ParCompactionManager(s) for the worker threads.
108 for(uint i=0; i<parallel_gc_threads; i++) {
109 _manager_array[i] = new ParCompactionManager();
110 guarantee(_manager_array[i] != NULL, "Could not create ParCompactionManager");
111 stack_array()->register_queue(i, _manager_array[i]->marking_stack());
112 _objarray_queues->register_queue(i, &_manager_array[i]->_objarray_stack);
113 region_array()->register_queue(i, region_list(i));
114 }
115
116 // The VMThread gets its own ParCompactionManager, which is not available
117 // for work stealing.
118 _manager_array[parallel_gc_threads] = new ParCompactionManager();
119 guarantee(_manager_array[parallel_gc_threads] != NULL,
120 "Could not create ParCompactionManager");
121 assert(PSParallelCompact::gc_task_manager()->workers() != 0,
122 "Not initialized?");
123 }
124
125 int ParCompactionManager::pop_recycled_stack_index() {
126 assert(_recycled_bottom <= _recycled_top, "list is empty");
127 // Get the next available index
128 if (_recycled_bottom < _recycled_top) {
129 uint cur, next, last;
130 do {
131 cur = _recycled_bottom;
132 next = cur + 1;
133 last = Atomic::cmpxchg(next, &_recycled_bottom, cur);
134 } while (cur != last);
135 return _recycled_stack_index[next];
136 } else {
137 return -1;
138 }
139 }
140
141 void ParCompactionManager::push_recycled_stack_index(uint v) {
142 // Get the next available index
143 int cur = Atomic::add(1, &_recycled_top);
144 _recycled_stack_index[cur] = v;
145 assert(_recycled_bottom <= _recycled_top, "list top and bottom are wrong");
146 }
147
148 bool ParCompactionManager::should_update() {
149 assert(action() != NotValid, "Action is not set");
150 return (action() == ParCompactionManager::Update) ||
151 (action() == ParCompactionManager::CopyAndUpdate) ||
152 (action() == ParCompactionManager::UpdateAndCopy);
153 }
154
155 bool ParCompactionManager::should_copy() {
156 assert(action() != NotValid, "Action is not set");
157 return (action() == ParCompactionManager::Copy) ||
158 (action() == ParCompactionManager::CopyAndUpdate) ||
159 (action() == ParCompactionManager::UpdateAndCopy);
160 }
161
162 void ParCompactionManager::region_list_push(uint list_index,
163 size_t region_index) {
164 region_list(list_index)->push(region_index);
165 }
166
167 void ParCompactionManager::verify_region_list_empty(uint list_index) {
168 assert(region_list(list_index)->is_empty(), "Not empty");
169 }
170
171 ParCompactionManager*
172 ParCompactionManager::gc_thread_compaction_manager(int index) {
173 assert(index >= 0 && index < (int)ParallelGCThreads, "index out of range");
174 assert(_manager_array != NULL, "Sanity");
175 return _manager_array[index];
176 }
177
178 void ParCompactionManager::follow_marking_stacks() {
179 do {
180 // Drain the overflow stack first, to allow stealing from the marking stack.
181 oop obj;
182 while (marking_stack()->pop_overflow(obj)) {
183 obj->follow_contents(this);
184 }
185 while (marking_stack()->pop_local(obj)) {
186 obj->follow_contents(this);
187 }
188
189 // Process ObjArrays one at a time to avoid marking stack bloat.
190 ObjArrayTask task;
191 if (_objarray_stack.pop_overflow(task) || _objarray_stack.pop_local(task)) {
192 ObjArrayKlass* k = (ObjArrayKlass*)task.obj()->klass();
193 k->oop_follow_contents(this, task.obj(), task.index());
194 }
195 } while (!marking_stacks_empty());
196
197 assert(marking_stacks_empty(), "Sanity");
198 }
199
200 void ParCompactionManager::drain_region_stacks() {
201 do {
202 // Drain overflow stack first so other threads can steal.
203 size_t region_index;
204 while (region_stack()->pop_overflow(region_index)) {
205 PSParallelCompact::fill_and_update_region(this, region_index);
206 }
207
208 while (region_stack()->pop_local(region_index)) {
209 PSParallelCompact::fill_and_update_region(this, region_index);
210 }
211 } while (!region_stack()->is_empty());
212 }