Sat, 23 Nov 2013 12:25:13 +0100
8028128: Add a type safe alternative for working with counter based data
Reviewed-by: dholmes, egahlin
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 */
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 "utilities/stack.inline.hpp"
39 PSOldGen* ParCompactionManager::_old_gen = NULL;
40 ParCompactionManager** ParCompactionManager::_manager_array = NULL;
42 RegionTaskQueue** ParCompactionManager::_region_list = NULL;
44 OopTaskQueueSet* ParCompactionManager::_stack_array = NULL;
45 ParCompactionManager::ObjArrayTaskQueueSet*
46 ParCompactionManager::_objarray_queues = NULL;
47 ObjectStartArray* ParCompactionManager::_start_array = NULL;
48 ParMarkBitMap* ParCompactionManager::_mark_bitmap = NULL;
49 RegionTaskQueueSet* ParCompactionManager::_region_array = NULL;
51 uint* ParCompactionManager::_recycled_stack_index = NULL;
52 int ParCompactionManager::_recycled_top = -1;
53 int ParCompactionManager::_recycled_bottom = -1;
55 ParCompactionManager::ParCompactionManager() :
56 _action(CopyAndUpdate),
57 _region_stack(NULL),
58 _region_stack_index((uint)max_uintx) {
60 ParallelScavengeHeap* heap = (ParallelScavengeHeap*)Universe::heap();
61 assert(heap->kind() == CollectedHeap::ParallelScavengeHeap, "Sanity");
63 _old_gen = heap->old_gen();
64 _start_array = old_gen()->start_array();
66 marking_stack()->initialize();
67 _objarray_stack.initialize();
68 }
70 ParCompactionManager::~ParCompactionManager() {
71 delete _recycled_stack_index;
72 }
74 void ParCompactionManager::initialize(ParMarkBitMap* mbm) {
75 assert(PSParallelCompact::gc_task_manager() != NULL,
76 "Needed for initialization");
78 _mark_bitmap = mbm;
80 uint parallel_gc_threads = PSParallelCompact::gc_task_manager()->workers();
82 assert(_manager_array == NULL, "Attempt to initialize twice");
83 _manager_array = NEW_C_HEAP_ARRAY(ParCompactionManager*, parallel_gc_threads+1, mtGC);
84 guarantee(_manager_array != NULL, "Could not allocate manager_array");
86 _region_list = NEW_C_HEAP_ARRAY(RegionTaskQueue*,
87 parallel_gc_threads+1, mtGC);
88 guarantee(_region_list != NULL, "Could not initialize promotion manager");
90 _recycled_stack_index = NEW_C_HEAP_ARRAY(uint, parallel_gc_threads, mtGC);
92 // parallel_gc-threads + 1 to be consistent with the number of
93 // compaction managers.
94 for(uint i=0; i<parallel_gc_threads + 1; i++) {
95 _region_list[i] = new RegionTaskQueue();
96 region_list(i)->initialize();
97 }
99 _stack_array = new OopTaskQueueSet(parallel_gc_threads);
100 guarantee(_stack_array != NULL, "Could not allocate stack_array");
101 _objarray_queues = new ObjArrayTaskQueueSet(parallel_gc_threads);
102 guarantee(_objarray_queues != NULL, "Could not allocate objarray_queues");
103 _region_array = new RegionTaskQueueSet(parallel_gc_threads);
104 guarantee(_region_array != NULL, "Could not allocate region_array");
106 // Create and register the ParCompactionManager(s) for the worker threads.
107 for(uint i=0; i<parallel_gc_threads; i++) {
108 _manager_array[i] = new ParCompactionManager();
109 guarantee(_manager_array[i] != NULL, "Could not create ParCompactionManager");
110 stack_array()->register_queue(i, _manager_array[i]->marking_stack());
111 _objarray_queues->register_queue(i, &_manager_array[i]->_objarray_stack);
112 region_array()->register_queue(i, region_list(i));
113 }
115 // The VMThread gets its own ParCompactionManager, which is not available
116 // for work stealing.
117 _manager_array[parallel_gc_threads] = new ParCompactionManager();
118 guarantee(_manager_array[parallel_gc_threads] != NULL,
119 "Could not create ParCompactionManager");
120 assert(PSParallelCompact::gc_task_manager()->workers() != 0,
121 "Not initialized?");
122 }
124 int ParCompactionManager::pop_recycled_stack_index() {
125 assert(_recycled_bottom <= _recycled_top, "list is empty");
126 // Get the next available index
127 if (_recycled_bottom < _recycled_top) {
128 uint cur, next, last;
129 do {
130 cur = _recycled_bottom;
131 next = cur + 1;
132 last = Atomic::cmpxchg(next, &_recycled_bottom, cur);
133 } while (cur != last);
134 return _recycled_stack_index[next];
135 } else {
136 return -1;
137 }
138 }
140 void ParCompactionManager::push_recycled_stack_index(uint v) {
141 // Get the next available index
142 int cur = Atomic::add(1, &_recycled_top);
143 _recycled_stack_index[cur] = v;
144 assert(_recycled_bottom <= _recycled_top, "list top and bottom are wrong");
145 }
147 bool ParCompactionManager::should_update() {
148 assert(action() != NotValid, "Action is not set");
149 return (action() == ParCompactionManager::Update) ||
150 (action() == ParCompactionManager::CopyAndUpdate) ||
151 (action() == ParCompactionManager::UpdateAndCopy);
152 }
154 bool ParCompactionManager::should_copy() {
155 assert(action() != NotValid, "Action is not set");
156 return (action() == ParCompactionManager::Copy) ||
157 (action() == ParCompactionManager::CopyAndUpdate) ||
158 (action() == ParCompactionManager::UpdateAndCopy);
159 }
161 void ParCompactionManager::region_list_push(uint list_index,
162 size_t region_index) {
163 region_list(list_index)->push(region_index);
164 }
166 void ParCompactionManager::verify_region_list_empty(uint list_index) {
167 assert(region_list(list_index)->is_empty(), "Not empty");
168 }
170 ParCompactionManager*
171 ParCompactionManager::gc_thread_compaction_manager(int index) {
172 assert(index >= 0 && index < (int)ParallelGCThreads, "index out of range");
173 assert(_manager_array != NULL, "Sanity");
174 return _manager_array[index];
175 }
177 void ParCompactionManager::follow_marking_stacks() {
178 do {
179 // Drain the overflow stack first, to allow stealing from the marking stack.
180 oop obj;
181 while (marking_stack()->pop_overflow(obj)) {
182 obj->follow_contents(this);
183 }
184 while (marking_stack()->pop_local(obj)) {
185 obj->follow_contents(this);
186 }
188 // Process ObjArrays one at a time to avoid marking stack bloat.
189 ObjArrayTask task;
190 if (_objarray_stack.pop_overflow(task) || _objarray_stack.pop_local(task)) {
191 ObjArrayKlass* k = (ObjArrayKlass*)task.obj()->klass();
192 k->oop_follow_contents(this, task.obj(), task.index());
193 }
194 } while (!marking_stacks_empty());
196 assert(marking_stacks_empty(), "Sanity");
197 }
199 void ParCompactionManager::drain_region_stacks() {
200 do {
201 // Drain overflow stack first so other threads can steal.
202 size_t region_index;
203 while (region_stack()->pop_overflow(region_index)) {
204 PSParallelCompact::fill_and_update_region(this, region_index);
205 }
207 while (region_stack()->pop_local(region_index)) {
208 PSParallelCompact::fill_and_update_region(this, region_index);
209 }
210 } while (!region_stack()->is_empty());
211 }