Thu, 17 Mar 2011 10:32:46 -0700
6668573: CMS: reference processing crash if ParallelCMSThreads > ParallelGCThreads
Summary: Use _max_num_q = max(discovery_degree, processing_degree), and let balance_queues() redistribute from discovery_degree to processing_degree of queues. This should also allow a more dynamic and flexible parallelism policy in the future.
Reviewed-by: jmasa, johnc
duke@435 | 1 | /* |
ysr@2651 | 2 | * Copyright (c) 2002, 2011, Oracle and/or its affiliates. All rights reserved. |
duke@435 | 3 | * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
duke@435 | 4 | * |
duke@435 | 5 | * This code is free software; you can redistribute it and/or modify it |
duke@435 | 6 | * under the terms of the GNU General Public License version 2 only, as |
duke@435 | 7 | * published by the Free Software Foundation. |
duke@435 | 8 | * |
duke@435 | 9 | * This code is distributed in the hope that it will be useful, but WITHOUT |
duke@435 | 10 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
duke@435 | 11 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
duke@435 | 12 | * version 2 for more details (a copy is included in the LICENSE file that |
duke@435 | 13 | * accompanied this code). |
duke@435 | 14 | * |
duke@435 | 15 | * You should have received a copy of the GNU General Public License version |
duke@435 | 16 | * 2 along with this work; if not, write to the Free Software Foundation, |
duke@435 | 17 | * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
duke@435 | 18 | * |
trims@1907 | 19 | * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
trims@1907 | 20 | * or visit www.oracle.com if you need additional information or have any |
trims@1907 | 21 | * questions. |
duke@435 | 22 | * |
duke@435 | 23 | */ |
duke@435 | 24 | |
stefank@2314 | 25 | #ifndef SHARE_VM_UTILITIES_WORKGROUP_HPP |
stefank@2314 | 26 | #define SHARE_VM_UTILITIES_WORKGROUP_HPP |
stefank@2314 | 27 | |
stefank@2314 | 28 | #include "utilities/taskqueue.hpp" |
stefank@2314 | 29 | #ifdef TARGET_OS_FAMILY_linux |
stefank@2314 | 30 | # include "thread_linux.inline.hpp" |
stefank@2314 | 31 | #endif |
stefank@2314 | 32 | #ifdef TARGET_OS_FAMILY_solaris |
stefank@2314 | 33 | # include "thread_solaris.inline.hpp" |
stefank@2314 | 34 | #endif |
stefank@2314 | 35 | #ifdef TARGET_OS_FAMILY_windows |
stefank@2314 | 36 | # include "thread_windows.inline.hpp" |
stefank@2314 | 37 | #endif |
stefank@2314 | 38 | |
ysr@2651 | 39 | // Task class hierarchy: |
ysr@2651 | 40 | // AbstractGangTask |
ysr@2651 | 41 | // AbstractGangTaskWOopQueues |
ysr@2651 | 42 | // |
ysr@2651 | 43 | // Gang/Group class hierarchy: |
ysr@2651 | 44 | // AbstractWorkGang |
ysr@2651 | 45 | // WorkGang |
ysr@2651 | 46 | // FlexibleWorkGang |
ysr@2651 | 47 | // YieldingFlexibleWorkGang (defined in another file) |
ysr@2651 | 48 | // |
ysr@2651 | 49 | // Worker class hierarchy: |
ysr@2651 | 50 | // GangWorker (subclass of WorkerThread) |
ysr@2651 | 51 | // YieldingFlexibleGangWorker (defined in another file) |
ysr@2651 | 52 | |
duke@435 | 53 | // Forward declarations of classes defined here |
duke@435 | 54 | |
duke@435 | 55 | class WorkGang; |
duke@435 | 56 | class GangWorker; |
duke@435 | 57 | class YieldingFlexibleGangWorker; |
duke@435 | 58 | class YieldingFlexibleGangTask; |
duke@435 | 59 | class WorkData; |
jmasa@2188 | 60 | class AbstractWorkGang; |
duke@435 | 61 | |
duke@435 | 62 | // An abstract task to be worked on by a gang. |
duke@435 | 63 | // You subclass this to supply your own work() method |
apetrusenko@984 | 64 | class AbstractGangTask VALUE_OBJ_CLASS_SPEC { |
duke@435 | 65 | public: |
duke@435 | 66 | // The abstract work method. |
duke@435 | 67 | // The argument tells you which member of the gang you are. |
duke@435 | 68 | virtual void work(int i) = 0; |
duke@435 | 69 | |
jmasa@2188 | 70 | // This method configures the task for proper termination. |
jmasa@2188 | 71 | // Some tasks do not have any requirements on termination |
jmasa@2188 | 72 | // and may inherit this method that does nothing. Some |
jmasa@2188 | 73 | // tasks do some coordination on termination and override |
jmasa@2188 | 74 | // this method to implement that coordination. |
jmasa@2188 | 75 | virtual void set_for_termination(int active_workers) {}; |
jmasa@2188 | 76 | |
duke@435 | 77 | // Debugging accessor for the name. |
duke@435 | 78 | const char* name() const PRODUCT_RETURN_(return NULL;); |
duke@435 | 79 | int counter() { return _counter; } |
duke@435 | 80 | void set_counter(int value) { _counter = value; } |
duke@435 | 81 | int *address_of_counter() { return &_counter; } |
duke@435 | 82 | |
duke@435 | 83 | // RTTI |
duke@435 | 84 | NOT_PRODUCT(virtual bool is_YieldingFlexibleGang_task() const { |
duke@435 | 85 | return false; |
duke@435 | 86 | }) |
duke@435 | 87 | |
duke@435 | 88 | private: |
duke@435 | 89 | NOT_PRODUCT(const char* _name;) |
duke@435 | 90 | // ??? Should a task have a priority associated with it? |
duke@435 | 91 | // ??? Or can the run method adjust priority as needed? |
duke@435 | 92 | int _counter; |
duke@435 | 93 | |
duke@435 | 94 | protected: |
duke@435 | 95 | // Constructor and desctructor: only construct subclasses. |
duke@435 | 96 | AbstractGangTask(const char* name) { |
duke@435 | 97 | NOT_PRODUCT(_name = name); |
duke@435 | 98 | _counter = 0; |
duke@435 | 99 | } |
duke@435 | 100 | virtual ~AbstractGangTask() { } |
duke@435 | 101 | }; |
duke@435 | 102 | |
jmasa@2188 | 103 | class AbstractGangTaskWOopQueues : public AbstractGangTask { |
jmasa@2188 | 104 | OopTaskQueueSet* _queues; |
jmasa@2188 | 105 | ParallelTaskTerminator _terminator; |
jmasa@2188 | 106 | public: |
jmasa@2188 | 107 | AbstractGangTaskWOopQueues(const char* name, OopTaskQueueSet* queues) : |
jmasa@2188 | 108 | AbstractGangTask(name), _queues(queues), _terminator(0, _queues) {} |
jmasa@2188 | 109 | ParallelTaskTerminator* terminator() { return &_terminator; } |
jmasa@2188 | 110 | virtual void set_for_termination(int active_workers) { |
jmasa@2188 | 111 | terminator()->reset_for_reuse(active_workers); |
jmasa@2188 | 112 | } |
jmasa@2188 | 113 | OopTaskQueueSet* queues() { return _queues; } |
jmasa@2188 | 114 | }; |
duke@435 | 115 | |
duke@435 | 116 | // Class AbstractWorkGang: |
duke@435 | 117 | // An abstract class representing a gang of workers. |
duke@435 | 118 | // You subclass this to supply an implementation of run_task(). |
duke@435 | 119 | class AbstractWorkGang: public CHeapObj { |
duke@435 | 120 | // Here's the public interface to this class. |
duke@435 | 121 | public: |
duke@435 | 122 | // Constructor and destructor. |
ysr@777 | 123 | AbstractWorkGang(const char* name, bool are_GC_task_threads, |
ysr@777 | 124 | bool are_ConcurrentGC_threads); |
duke@435 | 125 | ~AbstractWorkGang(); |
duke@435 | 126 | // Run a task, returns when the task is done (or terminated). |
duke@435 | 127 | virtual void run_task(AbstractGangTask* task) = 0; |
duke@435 | 128 | // Stop and terminate all workers. |
duke@435 | 129 | virtual void stop(); |
duke@435 | 130 | public: |
duke@435 | 131 | // Debugging. |
duke@435 | 132 | const char* name() const; |
duke@435 | 133 | protected: |
duke@435 | 134 | // Initialize only instance data. |
ysr@777 | 135 | const bool _are_GC_task_threads; |
ysr@777 | 136 | const bool _are_ConcurrentGC_threads; |
duke@435 | 137 | // Printing support. |
duke@435 | 138 | const char* _name; |
duke@435 | 139 | // The monitor which protects these data, |
duke@435 | 140 | // and notifies of changes in it. |
duke@435 | 141 | Monitor* _monitor; |
duke@435 | 142 | // The count of the number of workers in the gang. |
duke@435 | 143 | int _total_workers; |
duke@435 | 144 | // Whether the workers should terminate. |
duke@435 | 145 | bool _terminate; |
duke@435 | 146 | // The array of worker threads for this gang. |
duke@435 | 147 | // This is only needed for cleaning up. |
duke@435 | 148 | GangWorker** _gang_workers; |
duke@435 | 149 | // The task for this gang. |
duke@435 | 150 | AbstractGangTask* _task; |
duke@435 | 151 | // A sequence number for the current task. |
duke@435 | 152 | int _sequence_number; |
duke@435 | 153 | // The number of started workers. |
duke@435 | 154 | int _started_workers; |
duke@435 | 155 | // The number of finished workers. |
duke@435 | 156 | int _finished_workers; |
duke@435 | 157 | public: |
duke@435 | 158 | // Accessors for fields |
duke@435 | 159 | Monitor* monitor() const { |
duke@435 | 160 | return _monitor; |
duke@435 | 161 | } |
duke@435 | 162 | int total_workers() const { |
duke@435 | 163 | return _total_workers; |
duke@435 | 164 | } |
jmasa@2188 | 165 | virtual int active_workers() const { |
jmasa@2188 | 166 | return _total_workers; |
jmasa@2188 | 167 | } |
duke@435 | 168 | bool terminate() const { |
duke@435 | 169 | return _terminate; |
duke@435 | 170 | } |
duke@435 | 171 | GangWorker** gang_workers() const { |
duke@435 | 172 | return _gang_workers; |
duke@435 | 173 | } |
duke@435 | 174 | AbstractGangTask* task() const { |
duke@435 | 175 | return _task; |
duke@435 | 176 | } |
duke@435 | 177 | int sequence_number() const { |
duke@435 | 178 | return _sequence_number; |
duke@435 | 179 | } |
duke@435 | 180 | int started_workers() const { |
duke@435 | 181 | return _started_workers; |
duke@435 | 182 | } |
duke@435 | 183 | int finished_workers() const { |
duke@435 | 184 | return _finished_workers; |
duke@435 | 185 | } |
ysr@777 | 186 | bool are_GC_task_threads() const { |
ysr@777 | 187 | return _are_GC_task_threads; |
ysr@777 | 188 | } |
ysr@777 | 189 | bool are_ConcurrentGC_threads() const { |
ysr@777 | 190 | return _are_ConcurrentGC_threads; |
duke@435 | 191 | } |
duke@435 | 192 | // Predicates. |
duke@435 | 193 | bool is_idle() const { |
duke@435 | 194 | return (task() == NULL); |
duke@435 | 195 | } |
duke@435 | 196 | // Return the Ith gang worker. |
duke@435 | 197 | GangWorker* gang_worker(int i) const; |
duke@435 | 198 | |
duke@435 | 199 | void threads_do(ThreadClosure* tc) const; |
duke@435 | 200 | |
duke@435 | 201 | // Printing |
duke@435 | 202 | void print_worker_threads_on(outputStream *st) const; |
duke@435 | 203 | void print_worker_threads() const { |
duke@435 | 204 | print_worker_threads_on(tty); |
duke@435 | 205 | } |
duke@435 | 206 | |
duke@435 | 207 | protected: |
duke@435 | 208 | friend class GangWorker; |
duke@435 | 209 | friend class YieldingFlexibleGangWorker; |
duke@435 | 210 | // Note activation and deactivation of workers. |
duke@435 | 211 | // These methods should only be called with the mutex held. |
duke@435 | 212 | void internal_worker_poll(WorkData* data) const; |
duke@435 | 213 | void internal_note_start(); |
duke@435 | 214 | void internal_note_finish(); |
duke@435 | 215 | }; |
duke@435 | 216 | |
duke@435 | 217 | class WorkData: public StackObj { |
duke@435 | 218 | // This would be a struct, but I want accessor methods. |
duke@435 | 219 | private: |
duke@435 | 220 | bool _terminate; |
duke@435 | 221 | AbstractGangTask* _task; |
duke@435 | 222 | int _sequence_number; |
duke@435 | 223 | public: |
duke@435 | 224 | // Constructor and destructor |
duke@435 | 225 | WorkData() { |
duke@435 | 226 | _terminate = false; |
duke@435 | 227 | _task = NULL; |
duke@435 | 228 | _sequence_number = 0; |
duke@435 | 229 | } |
duke@435 | 230 | ~WorkData() { |
duke@435 | 231 | } |
duke@435 | 232 | // Accessors and modifiers |
duke@435 | 233 | bool terminate() const { return _terminate; } |
duke@435 | 234 | void set_terminate(bool value) { _terminate = value; } |
duke@435 | 235 | AbstractGangTask* task() const { return _task; } |
duke@435 | 236 | void set_task(AbstractGangTask* value) { _task = value; } |
duke@435 | 237 | int sequence_number() const { return _sequence_number; } |
duke@435 | 238 | void set_sequence_number(int value) { _sequence_number = value; } |
duke@435 | 239 | |
duke@435 | 240 | YieldingFlexibleGangTask* yf_task() const { |
duke@435 | 241 | return (YieldingFlexibleGangTask*)_task; |
duke@435 | 242 | } |
duke@435 | 243 | }; |
duke@435 | 244 | |
duke@435 | 245 | // Class WorkGang: |
duke@435 | 246 | class WorkGang: public AbstractWorkGang { |
duke@435 | 247 | public: |
duke@435 | 248 | // Constructor |
ysr@777 | 249 | WorkGang(const char* name, int workers, |
ysr@777 | 250 | bool are_GC_task_threads, bool are_ConcurrentGC_threads); |
duke@435 | 251 | // Run a task, returns when the task is done (or terminated). |
duke@435 | 252 | virtual void run_task(AbstractGangTask* task); |
jmasa@2188 | 253 | void run_task(AbstractGangTask* task, uint no_of_parallel_workers); |
jmasa@2188 | 254 | // Allocate a worker and return a pointer to it. |
jmasa@2188 | 255 | virtual GangWorker* allocate_worker(int which); |
jmasa@2188 | 256 | // Initialize workers in the gang. Return true if initialization |
jmasa@2188 | 257 | // succeeded. The type of the worker can be overridden in a derived |
jmasa@2188 | 258 | // class with the appropriate implementation of allocate_worker(). |
jmasa@2188 | 259 | bool initialize_workers(); |
duke@435 | 260 | }; |
duke@435 | 261 | |
duke@435 | 262 | // Class GangWorker: |
duke@435 | 263 | // Several instances of this class run in parallel as workers for a gang. |
duke@435 | 264 | class GangWorker: public WorkerThread { |
duke@435 | 265 | public: |
duke@435 | 266 | // Constructors and destructor. |
duke@435 | 267 | GangWorker(AbstractWorkGang* gang, uint id); |
duke@435 | 268 | |
duke@435 | 269 | // The only real method: run a task for the gang. |
duke@435 | 270 | virtual void run(); |
duke@435 | 271 | // Predicate for Thread |
duke@435 | 272 | virtual bool is_GC_task_thread() const; |
ysr@777 | 273 | virtual bool is_ConcurrentGC_thread() const; |
duke@435 | 274 | // Printing |
duke@435 | 275 | void print_on(outputStream* st) const; |
duke@435 | 276 | virtual void print() const { print_on(tty); } |
duke@435 | 277 | protected: |
duke@435 | 278 | AbstractWorkGang* _gang; |
duke@435 | 279 | |
duke@435 | 280 | virtual void initialize(); |
duke@435 | 281 | virtual void loop(); |
duke@435 | 282 | |
duke@435 | 283 | public: |
duke@435 | 284 | AbstractWorkGang* gang() const { return _gang; } |
duke@435 | 285 | }; |
duke@435 | 286 | |
jmasa@2188 | 287 | class FlexibleWorkGang: public WorkGang { |
jmasa@2188 | 288 | protected: |
jmasa@2188 | 289 | int _active_workers; |
jmasa@2188 | 290 | public: |
jmasa@2188 | 291 | // Constructor and destructor. |
jmasa@2188 | 292 | FlexibleWorkGang(const char* name, int workers, |
jmasa@2188 | 293 | bool are_GC_task_threads, |
jmasa@2188 | 294 | bool are_ConcurrentGC_threads) : |
jmasa@2188 | 295 | WorkGang(name, workers, are_GC_task_threads, are_ConcurrentGC_threads) { |
jmasa@2188 | 296 | _active_workers = ParallelGCThreads; |
jmasa@2188 | 297 | }; |
jmasa@2188 | 298 | // Accessors for fields |
jmasa@2188 | 299 | virtual int active_workers() const { return _active_workers; } |
jmasa@2188 | 300 | void set_active_workers(int v) { _active_workers = v; } |
jmasa@2188 | 301 | }; |
jmasa@2188 | 302 | |
jmasa@2188 | 303 | // Work gangs in garbage collectors: 2009-06-10 |
jmasa@2188 | 304 | // |
jmasa@2188 | 305 | // SharedHeap - work gang for stop-the-world parallel collection. |
jmasa@2188 | 306 | // Used by |
jmasa@2188 | 307 | // ParNewGeneration |
jmasa@2188 | 308 | // CMSParRemarkTask |
jmasa@2188 | 309 | // CMSRefProcTaskExecutor |
jmasa@2188 | 310 | // G1CollectedHeap |
jmasa@2188 | 311 | // G1ParFinalCountTask |
jmasa@2188 | 312 | // ConcurrentMark |
jmasa@2188 | 313 | // CMSCollector |
jmasa@2188 | 314 | |
duke@435 | 315 | // A class that acts as a synchronisation barrier. Workers enter |
duke@435 | 316 | // the barrier and must wait until all other workers have entered |
duke@435 | 317 | // before any of them may leave. |
duke@435 | 318 | |
duke@435 | 319 | class WorkGangBarrierSync : public StackObj { |
duke@435 | 320 | protected: |
duke@435 | 321 | Monitor _monitor; |
duke@435 | 322 | int _n_workers; |
duke@435 | 323 | int _n_completed; |
ysr@777 | 324 | bool _should_reset; |
duke@435 | 325 | |
ysr@777 | 326 | Monitor* monitor() { return &_monitor; } |
ysr@777 | 327 | int n_workers() { return _n_workers; } |
ysr@777 | 328 | int n_completed() { return _n_completed; } |
ysr@777 | 329 | bool should_reset() { return _should_reset; } |
duke@435 | 330 | |
ysr@777 | 331 | void zero_completed() { _n_completed = 0; } |
ysr@777 | 332 | void inc_completed() { _n_completed++; } |
ysr@777 | 333 | |
ysr@777 | 334 | void set_should_reset(bool v) { _should_reset = v; } |
duke@435 | 335 | |
duke@435 | 336 | public: |
duke@435 | 337 | WorkGangBarrierSync(); |
duke@435 | 338 | WorkGangBarrierSync(int n_workers, const char* name); |
duke@435 | 339 | |
duke@435 | 340 | // Set the number of workers that will use the barrier. |
duke@435 | 341 | // Must be called before any of the workers start running. |
duke@435 | 342 | void set_n_workers(int n_workers); |
duke@435 | 343 | |
duke@435 | 344 | // Enter the barrier. A worker that enters the barrier will |
duke@435 | 345 | // not be allowed to leave until all other threads have |
duke@435 | 346 | // also entered the barrier. |
duke@435 | 347 | void enter(); |
duke@435 | 348 | }; |
duke@435 | 349 | |
duke@435 | 350 | // A class to manage claiming of subtasks within a group of tasks. The |
duke@435 | 351 | // subtasks will be identified by integer indices, usually elements of an |
duke@435 | 352 | // enumeration type. |
duke@435 | 353 | |
duke@435 | 354 | class SubTasksDone: public CHeapObj { |
duke@435 | 355 | jint* _tasks; |
duke@435 | 356 | int _n_tasks; |
duke@435 | 357 | int _n_threads; |
duke@435 | 358 | jint _threads_completed; |
duke@435 | 359 | #ifdef ASSERT |
jmasa@2188 | 360 | volatile jint _claimed; |
duke@435 | 361 | #endif |
duke@435 | 362 | |
duke@435 | 363 | // Set all tasks to unclaimed. |
duke@435 | 364 | void clear(); |
duke@435 | 365 | |
duke@435 | 366 | public: |
duke@435 | 367 | // Initializes "this" to a state in which there are "n" tasks to be |
duke@435 | 368 | // processed, none of the which are originally claimed. The number of |
duke@435 | 369 | // threads doing the tasks is initialized 1. |
duke@435 | 370 | SubTasksDone(int n); |
duke@435 | 371 | |
duke@435 | 372 | // True iff the object is in a valid state. |
duke@435 | 373 | bool valid(); |
duke@435 | 374 | |
jmasa@2188 | 375 | // Get/set the number of parallel threads doing the tasks to "t". Can only |
duke@435 | 376 | // be called before tasks start or after they are complete. |
jmasa@2188 | 377 | int n_threads() { return _n_threads; } |
jmasa@2188 | 378 | void set_n_threads(int t); |
duke@435 | 379 | |
duke@435 | 380 | // Returns "false" if the task "t" is unclaimed, and ensures that task is |
duke@435 | 381 | // claimed. The task "t" is required to be within the range of "this". |
duke@435 | 382 | bool is_task_claimed(int t); |
duke@435 | 383 | |
duke@435 | 384 | // The calling thread asserts that it has attempted to claim all the |
duke@435 | 385 | // tasks that it will try to claim. Every thread in the parallel task |
duke@435 | 386 | // must execute this. (When the last thread does so, the task array is |
duke@435 | 387 | // cleared.) |
duke@435 | 388 | void all_tasks_completed(); |
duke@435 | 389 | |
duke@435 | 390 | // Destructor. |
duke@435 | 391 | ~SubTasksDone(); |
duke@435 | 392 | }; |
duke@435 | 393 | |
duke@435 | 394 | // As above, but for sequential tasks, i.e. instead of claiming |
duke@435 | 395 | // sub-tasks from a set (possibly an enumeration), claim sub-tasks |
duke@435 | 396 | // in sequential order. This is ideal for claiming dynamically |
duke@435 | 397 | // partitioned tasks (like striding in the parallel remembered |
duke@435 | 398 | // set scanning). Note that unlike the above class this is |
duke@435 | 399 | // a stack object - is there any reason for it not to be? |
duke@435 | 400 | |
duke@435 | 401 | class SequentialSubTasksDone : public StackObj { |
duke@435 | 402 | protected: |
duke@435 | 403 | jint _n_tasks; // Total number of tasks available. |
duke@435 | 404 | jint _n_claimed; // Number of tasks claimed. |
jmasa@2188 | 405 | // _n_threads is used to determine when a sub task is done. |
jmasa@2188 | 406 | // See comments on SubTasksDone::_n_threads |
duke@435 | 407 | jint _n_threads; // Total number of parallel threads. |
duke@435 | 408 | jint _n_completed; // Number of completed threads. |
duke@435 | 409 | |
duke@435 | 410 | void clear(); |
duke@435 | 411 | |
duke@435 | 412 | public: |
jmasa@2188 | 413 | SequentialSubTasksDone() { |
jmasa@2188 | 414 | clear(); |
jmasa@2188 | 415 | } |
duke@435 | 416 | ~SequentialSubTasksDone() {} |
duke@435 | 417 | |
duke@435 | 418 | // True iff the object is in a valid state. |
duke@435 | 419 | bool valid(); |
duke@435 | 420 | |
duke@435 | 421 | // number of tasks |
duke@435 | 422 | jint n_tasks() const { return _n_tasks; } |
duke@435 | 423 | |
jmasa@2188 | 424 | // Get/set the number of parallel threads doing the tasks to t. |
duke@435 | 425 | // Should be called before the task starts but it is safe |
duke@435 | 426 | // to call this once a task is running provided that all |
duke@435 | 427 | // threads agree on the number of threads. |
jmasa@2188 | 428 | int n_threads() { return _n_threads; } |
jmasa@2188 | 429 | void set_n_threads(int t) { _n_threads = t; } |
duke@435 | 430 | |
duke@435 | 431 | // Set the number of tasks to be claimed to t. As above, |
duke@435 | 432 | // should be called before the tasks start but it is safe |
duke@435 | 433 | // to call this once a task is running provided all threads |
duke@435 | 434 | // agree on the number of tasks. |
duke@435 | 435 | void set_n_tasks(int t) { _n_tasks = t; } |
duke@435 | 436 | |
duke@435 | 437 | // Returns false if the next task in the sequence is unclaimed, |
duke@435 | 438 | // and ensures that it is claimed. Will set t to be the index |
duke@435 | 439 | // of the claimed task in the sequence. Will return true if |
duke@435 | 440 | // the task cannot be claimed and there are none left to claim. |
duke@435 | 441 | bool is_task_claimed(int& t); |
duke@435 | 442 | |
duke@435 | 443 | // The calling thread asserts that it has attempted to claim |
duke@435 | 444 | // all the tasks it possibly can in the sequence. Every thread |
duke@435 | 445 | // claiming tasks must promise call this. Returns true if this |
duke@435 | 446 | // is the last thread to complete so that the thread can perform |
duke@435 | 447 | // cleanup if necessary. |
duke@435 | 448 | bool all_tasks_completed(); |
duke@435 | 449 | }; |
ysr@777 | 450 | |
ysr@777 | 451 | // Represents a set of free small integer ids. |
ysr@777 | 452 | class FreeIdSet { |
ysr@777 | 453 | enum { |
ysr@777 | 454 | end_of_list = -1, |
ysr@777 | 455 | claimed = -2 |
ysr@777 | 456 | }; |
ysr@777 | 457 | |
ysr@777 | 458 | int _sz; |
ysr@777 | 459 | Monitor* _mon; |
ysr@777 | 460 | |
ysr@777 | 461 | int* _ids; |
ysr@777 | 462 | int _hd; |
ysr@777 | 463 | int _waiters; |
ysr@777 | 464 | int _claimed; |
ysr@777 | 465 | |
ysr@777 | 466 | static bool _safepoint; |
ysr@777 | 467 | typedef FreeIdSet* FreeIdSetPtr; |
ysr@777 | 468 | static const int NSets = 10; |
ysr@777 | 469 | static FreeIdSetPtr _sets[NSets]; |
ysr@777 | 470 | static bool _stat_init; |
ysr@777 | 471 | int _index; |
ysr@777 | 472 | |
ysr@777 | 473 | public: |
ysr@777 | 474 | FreeIdSet(int sz, Monitor* mon); |
ysr@777 | 475 | ~FreeIdSet(); |
ysr@777 | 476 | |
ysr@777 | 477 | static void set_safepoint(bool b); |
ysr@777 | 478 | |
ysr@777 | 479 | // Attempt to claim the given id permanently. Returns "true" iff |
ysr@777 | 480 | // successful. |
ysr@777 | 481 | bool claim_perm_id(int i); |
ysr@777 | 482 | |
ysr@777 | 483 | // Returns an unclaimed parallel id (waiting for one to be released if |
ysr@777 | 484 | // necessary). Returns "-1" if a GC wakes up a wait for an id. |
ysr@777 | 485 | int claim_par_id(); |
ysr@777 | 486 | |
ysr@777 | 487 | void release_par_id(int id); |
ysr@777 | 488 | }; |
stefank@2314 | 489 | |
stefank@2314 | 490 | #endif // SHARE_VM_UTILITIES_WORKGROUP_HPP |