1 /*
2 * Copyright (c) 2005, 2011, 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 #ifndef SHARE_VM_GC_IMPLEMENTATION_PARALLELSCAVENGE_PCTASKS_HPP
26 #define SHARE_VM_GC_IMPLEMENTATION_PARALLELSCAVENGE_PCTASKS_HPP
27
28 #include "gc_implementation/parallelScavenge/gcTaskManager.hpp"
29 #include "gc_implementation/parallelScavenge/psParallelCompact.hpp"
30 #include "gc_implementation/parallelScavenge/psTasks.hpp"
31
32
33 // Tasks for parallel compaction of the old generation
34 //
35 // Tasks are created and enqueued on a task queue. The
36 // tasks for parallel old collector for marking objects
37 // are MarkFromRootsTask and ThreadRootsMarkingTask.
38 //
39 // MarkFromRootsTask's are created
40 // with a root group (e.g., jni_handles) and when the do_it()
41 // method of a MarkFromRootsTask is executed, it starts marking
42 // form it's root group.
43 //
44 // ThreadRootsMarkingTask's are created for each Java thread. When
45 // the do_it() method of a ThreadRootsMarkingTask is executed, it
46 // starts marking from the thread's roots.
47 //
48 // The enqueuing of the MarkFromRootsTask and ThreadRootsMarkingTask
49 // do little more than create the task and put it on a queue. The
50 // queue is a GCTaskQueue and threads steal tasks from this GCTaskQueue.
51 //
52 // In addition to the MarkFromRootsTask and ThreadRootsMarkingTask
53 // tasks there are StealMarkingTask tasks. The StealMarkingTask's
54 // steal a reference from the marking stack of another
55 // thread and transitively marks the object of the reference
56 // and internal references. After successfully stealing a reference
57 // and marking it, the StealMarkingTask drains its marking stack
58 // stack before attempting another steal.
59 //
60 // ThreadRootsMarkingTask
61 //
62 // This task marks from the roots of a single thread. This task
63 // enables marking of thread roots in parallel.
64 //
65
66 class ParallelTaskTerminator;
67
68 class ThreadRootsMarkingTask : public GCTask {
69 private:
70 JavaThread* _java_thread;
71 VMThread* _vm_thread;
72 public:
73 ThreadRootsMarkingTask(JavaThread* root) : _java_thread(root), _vm_thread(NULL) {}
74 ThreadRootsMarkingTask(VMThread* root) : _java_thread(NULL), _vm_thread(root) {}
75
76 char* name() { return (char *)"thread-roots-marking-task"; }
77
78 virtual void do_it(GCTaskManager* manager, uint which);
79 };
80
81
82 //
83 // MarkFromRootsTask
84 //
85 // This task marks from all the roots to all live
86 // objects.
87 //
88 //
89
90 class MarkFromRootsTask : public GCTask {
91 public:
92 enum RootType {
93 universe = 1,
94 jni_handles = 2,
95 threads = 3,
96 object_synchronizer = 4,
97 flat_profiler = 5,
98 management = 6,
99 jvmti = 7,
100 system_dictionary = 8,
101 class_loader_data = 9,
102 code_cache = 10
103 };
104 private:
105 RootType _root_type;
106 public:
107 MarkFromRootsTask(RootType value) : _root_type(value) {}
108
109 char* name() { return (char *)"mark-from-roots-task"; }
110
111 virtual void do_it(GCTaskManager* manager, uint which);
112 };
113
114 //
115 // RefProcTaskProxy
116 //
117 // This task is used as a proxy to parallel reference processing tasks .
118 //
119
120 class RefProcTaskProxy : public GCTask {
121 typedef AbstractRefProcTaskExecutor::ProcessTask ProcessTask;
122 ProcessTask & _rp_task;
123 uint _work_id;
124 public:
125 RefProcTaskProxy(ProcessTask & rp_task, uint work_id)
126 : _rp_task(rp_task),
127 _work_id(work_id)
128 { }
129
130 private:
131 virtual char* name() { return (char *)"Process referents by policy in parallel"; }
132
133 virtual void do_it(GCTaskManager* manager, uint which);
134 };
135
136
137
138 //
139 // RefEnqueueTaskProxy
140 //
141 // This task is used as a proxy to parallel reference processing tasks .
142 //
143
144 class RefEnqueueTaskProxy: public GCTask {
145 typedef AbstractRefProcTaskExecutor::EnqueueTask EnqueueTask;
146 EnqueueTask& _enq_task;
147 uint _work_id;
148
149 public:
150 RefEnqueueTaskProxy(EnqueueTask& enq_task, uint work_id)
151 : _enq_task(enq_task),
152 _work_id(work_id)
153 { }
154
155 virtual char* name() { return (char *)"Enqueue reference objects in parallel"; }
156 virtual void do_it(GCTaskManager* manager, uint which)
157 {
158 _enq_task.work(_work_id);
159 }
160 };
161
162
163 //
164 // RefProcTaskExecutor
165 //
166 // Task executor is an interface for the reference processor to run
167 // tasks using GCTaskManager.
168 //
169
170 class RefProcTaskExecutor: public AbstractRefProcTaskExecutor {
171 virtual void execute(ProcessTask& task);
172 virtual void execute(EnqueueTask& task);
173 };
174
175
176 //
177 // StealMarkingTask
178 //
179 // This task is used to distribute work to idle threads.
180 //
181
182 class StealMarkingTask : public GCTask {
183 private:
184 ParallelTaskTerminator* const _terminator;
185 private:
186
187 public:
188 char* name() { return (char *)"steal-marking-task"; }
189
190 StealMarkingTask(ParallelTaskTerminator* t);
191
192 ParallelTaskTerminator* terminator() { return _terminator; }
193
194 virtual void do_it(GCTaskManager* manager, uint which);
195 };
196
197 //
198 // StealRegionCompactionTask
199 //
200 // This task is used to distribute work to idle threads.
201 //
202
203 class StealRegionCompactionTask : public GCTask {
204 private:
205 ParallelTaskTerminator* const _terminator;
206 public:
207 StealRegionCompactionTask(ParallelTaskTerminator* t);
208
209 char* name() { return (char *)"steal-region-task"; }
210 ParallelTaskTerminator* terminator() { return _terminator; }
211
212 virtual void do_it(GCTaskManager* manager, uint which);
213 };
214
215 //
216 // UpdateDensePrefixTask
217 //
218 // This task is used to update the dense prefix
219 // of a space.
220 //
221
222 class UpdateDensePrefixTask : public GCTask {
223 private:
224 PSParallelCompact::SpaceId _space_id;
225 size_t _region_index_start;
226 size_t _region_index_end;
227
228 public:
229 char* name() { return (char *)"update-dense_prefix-task"; }
230
231 UpdateDensePrefixTask(PSParallelCompact::SpaceId space_id,
232 size_t region_index_start,
233 size_t region_index_end);
234
235 virtual void do_it(GCTaskManager* manager, uint which);
236 };
237
238 //
239 // DrainStacksCompactionTask
240 //
241 // This task processes regions that have been added to the stacks of each
242 // compaction manager.
243 //
244 // Trying to use one draining thread does not work because there are no
245 // guarantees about which task will be picked up by which thread. For example,
246 // if thread A gets all the preloaded regions, thread A may not get a draining
247 // task (they may all be done by other threads).
248 //
249
250 class DrainStacksCompactionTask : public GCTask {
251 uint _stack_index;
252 uint stack_index() { return _stack_index; }
253 public:
254 DrainStacksCompactionTask(uint stack_index) : GCTask(),
255 _stack_index(stack_index) {};
256 char* name() { return (char *)"drain-region-task"; }
257 virtual void do_it(GCTaskManager* manager, uint which);
258 };
259
260 #endif // SHARE_VM_GC_IMPLEMENTATION_PARALLELSCAVENGE_PCTASKS_HPP