Mercurial > hg > truffle
annotate src/share/vm/gc_implementation/parallelScavenge/pcTasks.hpp @ 453:c96030fff130
6684579: SoftReference processing can be made more efficient
Summary: For current soft-ref clearing policies, we can decide at marking time if a soft-reference will definitely not be cleared, postponing the decision of whether it will definitely be cleared to the final reference processing phase. This can be especially beneficial in the case of concurrent collectors where the marking is usually concurrent but reference processing is usually not.
Reviewed-by: jmasa
| author | ysr |
|---|---|
| date | Thu, 20 Nov 2008 16:56:09 -0800 |
| parents | 81cd571500b0 |
| children | ad8c8ca4ab0f |
| rev | line source |
|---|---|
| 0 | 1 /* |
| 2 * Copyright 2005-2007 Sun Microsystems, Inc. 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, | |
| 20 * CA 95054 USA or visit www.sun.com if you need additional information or | |
| 21 * have any questions. | |
| 22 * | |
| 23 */ | |
| 24 | |
| 25 | |
| 26 // Tasks for parallel compaction of the old generation | |
| 27 // | |
| 28 // Tasks are created and enqueued on a task queue. The | |
| 29 // tasks for parallel old collector for marking objects | |
| 30 // are MarkFromRootsTask and ThreadRootsMarkingTask. | |
| 31 // | |
| 32 // MarkFromRootsTask's are created | |
| 33 // with a root group (e.g., jni_handles) and when the do_it() | |
| 34 // method of a MarkFromRootsTask is executed, it starts marking | |
| 35 // form it's root group. | |
| 36 // | |
| 37 // ThreadRootsMarkingTask's are created for each Java thread. When | |
| 38 // the do_it() method of a ThreadRootsMarkingTask is executed, it | |
| 39 // starts marking from the thread's roots. | |
| 40 // | |
| 41 // The enqueuing of the MarkFromRootsTask and ThreadRootsMarkingTask | |
| 42 // do little more than create the task and put it on a queue. The | |
| 43 // queue is a GCTaskQueue and threads steal tasks from this GCTaskQueue. | |
| 44 // | |
| 45 // In addition to the MarkFromRootsTask and ThreadRootsMarkingTask | |
| 46 // tasks there are StealMarkingTask tasks. The StealMarkingTask's | |
| 47 // steal a reference from the marking stack of another | |
| 48 // thread and transitively marks the object of the reference | |
| 49 // and internal references. After successfully stealing a reference | |
| 50 // and marking it, the StealMarkingTask drains its marking stack | |
| 51 // stack before attempting another steal. | |
| 52 // | |
| 53 // ThreadRootsMarkingTask | |
| 54 // | |
| 55 // This task marks from the roots of a single thread. This task | |
| 56 // enables marking of thread roots in parallel. | |
| 57 // | |
| 58 | |
| 59 class ParallelTaskTerminator; | |
| 60 | |
| 61 class ThreadRootsMarkingTask : public GCTask { | |
| 62 private: | |
| 63 JavaThread* _java_thread; | |
| 64 VMThread* _vm_thread; | |
| 65 public: | |
| 66 ThreadRootsMarkingTask(JavaThread* root) : _java_thread(root), _vm_thread(NULL) {} | |
| 67 ThreadRootsMarkingTask(VMThread* root) : _java_thread(NULL), _vm_thread(root) {} | |
| 68 | |
| 69 char* name() { return (char *)"thread-roots-marking-task"; } | |
| 70 | |
| 71 virtual void do_it(GCTaskManager* manager, uint which); | |
| 72 }; | |
| 73 | |
| 74 | |
| 75 // | |
| 76 // MarkFromRootsTask | |
| 77 // | |
| 78 // This task marks from all the roots to all live | |
| 79 // objects. | |
| 80 // | |
| 81 // | |
| 82 | |
| 83 class MarkFromRootsTask : public GCTask { | |
| 84 public: | |
| 85 enum RootType { | |
| 86 universe = 1, | |
| 87 jni_handles = 2, | |
| 88 threads = 3, | |
| 89 object_synchronizer = 4, | |
| 90 flat_profiler = 5, | |
| 91 management = 6, | |
| 92 jvmti = 7, | |
| 93 system_dictionary = 8, | |
| 94 vm_symbols = 9, | |
| 95 reference_processing = 10 | |
| 96 }; | |
| 97 private: | |
| 98 RootType _root_type; | |
| 99 public: | |
| 100 MarkFromRootsTask(RootType value) : _root_type(value) {} | |
| 101 | |
| 102 char* name() { return (char *)"mark-from-roots-task"; } | |
| 103 | |
| 104 virtual void do_it(GCTaskManager* manager, uint which); | |
| 105 }; | |
| 106 | |
| 107 // | |
| 108 // RefProcTaskProxy | |
| 109 // | |
| 110 // This task is used as a proxy to parallel reference processing tasks . | |
| 111 // | |
| 112 | |
| 113 class RefProcTaskProxy : public GCTask { | |
| 114 typedef AbstractRefProcTaskExecutor::ProcessTask ProcessTask; | |
| 115 ProcessTask & _rp_task; | |
| 116 uint _work_id; | |
| 117 public: | |
| 118 RefProcTaskProxy(ProcessTask & rp_task, uint work_id) | |
| 119 : _rp_task(rp_task), | |
| 120 _work_id(work_id) | |
| 121 { } | |
| 122 | |
| 123 private: | |
| 124 virtual char* name() { return (char *)"Process referents by policy in parallel"; } | |
| 125 | |
| 126 virtual void do_it(GCTaskManager* manager, uint which); | |
| 127 }; | |
| 128 | |
| 129 | |
| 130 | |
| 131 // | |
| 132 // RefEnqueueTaskProxy | |
| 133 // | |
| 134 // This task is used as a proxy to parallel reference processing tasks . | |
| 135 // | |
| 136 | |
| 137 class RefEnqueueTaskProxy: public GCTask { | |
| 138 typedef AbstractRefProcTaskExecutor::EnqueueTask EnqueueTask; | |
| 139 EnqueueTask& _enq_task; | |
| 140 uint _work_id; | |
| 141 | |
| 142 public: | |
| 143 RefEnqueueTaskProxy(EnqueueTask& enq_task, uint work_id) | |
| 144 : _enq_task(enq_task), | |
| 145 _work_id(work_id) | |
| 146 { } | |
| 147 | |
| 148 virtual char* name() { return (char *)"Enqueue reference objects in parallel"; } | |
| 149 virtual void do_it(GCTaskManager* manager, uint which) | |
| 150 { | |
| 151 _enq_task.work(_work_id); | |
| 152 } | |
| 153 }; | |
| 154 | |
| 155 | |
| 156 // | |
| 157 // RefProcTaskExecutor | |
| 158 // | |
| 159 // Task executor is an interface for the reference processor to run | |
| 160 // tasks using GCTaskManager. | |
| 161 // | |
| 162 | |
| 163 class RefProcTaskExecutor: public AbstractRefProcTaskExecutor { | |
| 164 virtual void execute(ProcessTask& task); | |
| 165 virtual void execute(EnqueueTask& task); | |
| 166 }; | |
| 167 | |
| 168 | |
| 169 // | |
| 170 // StealMarkingTask | |
| 171 // | |
| 172 // This task is used to distribute work to idle threads. | |
| 173 // | |
| 174 | |
| 175 class StealMarkingTask : public GCTask { | |
| 176 private: | |
| 177 ParallelTaskTerminator* const _terminator; | |
| 178 private: | |
| 179 | |
| 180 public: | |
| 181 char* name() { return (char *)"steal-marking-task"; } | |
| 182 | |
| 183 StealMarkingTask(ParallelTaskTerminator* t); | |
| 184 | |
| 185 ParallelTaskTerminator* terminator() { return _terminator; } | |
| 186 | |
| 187 virtual void do_it(GCTaskManager* manager, uint which); | |
| 188 }; | |
| 189 | |
| 190 // | |
|
375
81cd571500b0
6725697: par compact - rename class ChunkData to RegionData
jcoomes
parents:
0
diff
changeset
|
191 // StealRegionCompactionTask |
| 0 | 192 // |
| 193 // This task is used to distribute work to idle threads. | |
| 194 // | |
| 195 | |
|
375
81cd571500b0
6725697: par compact - rename class ChunkData to RegionData
jcoomes
parents:
0
diff
changeset
|
196 class StealRegionCompactionTask : public GCTask { |
| 0 | 197 private: |
| 198 ParallelTaskTerminator* const _terminator; | |
| 199 public: | |
|
375
81cd571500b0
6725697: par compact - rename class ChunkData to RegionData
jcoomes
parents:
0
diff
changeset
|
200 StealRegionCompactionTask(ParallelTaskTerminator* t); |
| 0 | 201 |
|
375
81cd571500b0
6725697: par compact - rename class ChunkData to RegionData
jcoomes
parents:
0
diff
changeset
|
202 char* name() { return (char *)"steal-region-task"; } |
| 0 | 203 ParallelTaskTerminator* terminator() { return _terminator; } |
| 204 | |
| 205 virtual void do_it(GCTaskManager* manager, uint which); | |
| 206 }; | |
| 207 | |
| 208 // | |
| 209 // UpdateDensePrefixTask | |
| 210 // | |
| 211 // This task is used to update the dense prefix | |
| 212 // of a space. | |
| 213 // | |
| 214 | |
| 215 class UpdateDensePrefixTask : public GCTask { | |
| 216 private: | |
| 217 PSParallelCompact::SpaceId _space_id; | |
|
375
81cd571500b0
6725697: par compact - rename class ChunkData to RegionData
jcoomes
parents:
0
diff
changeset
|
218 size_t _region_index_start; |
|
81cd571500b0
6725697: par compact - rename class ChunkData to RegionData
jcoomes
parents:
0
diff
changeset
|
219 size_t _region_index_end; |
| 0 | 220 |
| 221 public: | |
| 222 char* name() { return (char *)"update-dense_prefix-task"; } | |
| 223 | |
| 224 UpdateDensePrefixTask(PSParallelCompact::SpaceId space_id, | |
|
375
81cd571500b0
6725697: par compact - rename class ChunkData to RegionData
jcoomes
parents:
0
diff
changeset
|
225 size_t region_index_start, |
|
81cd571500b0
6725697: par compact - rename class ChunkData to RegionData
jcoomes
parents:
0
diff
changeset
|
226 size_t region_index_end); |
| 0 | 227 |
| 228 virtual void do_it(GCTaskManager* manager, uint which); | |
| 229 }; | |
| 230 | |
| 231 // | |
| 232 // DrainStacksCompactionTask | |
| 233 // | |
|
375
81cd571500b0
6725697: par compact - rename class ChunkData to RegionData
jcoomes
parents:
0
diff
changeset
|
234 // This task processes regions that have been added to the stacks of each |
| 0 | 235 // compaction manager. |
| 236 // | |
| 237 // Trying to use one draining thread does not work because there are no | |
| 238 // guarantees about which task will be picked up by which thread. For example, | |
|
375
81cd571500b0
6725697: par compact - rename class ChunkData to RegionData
jcoomes
parents:
0
diff
changeset
|
239 // if thread A gets all the preloaded regions, thread A may not get a draining |
| 0 | 240 // task (they may all be done by other threads). |
| 241 // | |
| 242 | |
| 243 class DrainStacksCompactionTask : public GCTask { | |
| 244 public: | |
|
375
81cd571500b0
6725697: par compact - rename class ChunkData to RegionData
jcoomes
parents:
0
diff
changeset
|
245 char* name() { return (char *)"drain-region-task"; } |
| 0 | 246 virtual void do_it(GCTaskManager* manager, uint which); |
| 247 }; |