5 |
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*/ |
6 |
|
|
7 |
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package jsr166y; |
8 |
< |
import java.util.*; |
8 |
> |
|
9 |
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import java.util.concurrent.*; |
10 |
< |
import java.util.concurrent.atomic.*; |
11 |
< |
import java.util.concurrent.locks.*; |
12 |
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import sun.misc.Unsafe; |
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import java.lang.reflect.*; |
10 |
> |
|
11 |
> |
import java.util.Collection; |
12 |
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|
13 |
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/** |
14 |
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* A thread managed by a {@link ForkJoinPool}. This class is |
15 |
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* subclassable solely for the sake of adding functionality -- there |
16 |
< |
* are no overridable methods dealing with scheduling or |
17 |
< |
* execution. However, you can override initialization and termination |
18 |
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* cleanup methods surrounding the main task processing loop. If you |
19 |
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* do create such a subclass, you will also need to supply a custom |
20 |
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* ForkJoinWorkerThreadFactory to use it in a ForkJoinPool. |
21 |
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* |
16 |
> |
* are no overridable methods dealing with scheduling or execution. |
17 |
> |
* However, you can override initialization and termination methods |
18 |
> |
* surrounding the main task processing loop. If you do create such a |
19 |
> |
* subclass, you will also need to supply a custom {@link |
20 |
> |
* ForkJoinPool.ForkJoinWorkerThreadFactory} to use it in a {@code |
21 |
> |
* ForkJoinPool}. |
22 |
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* |
23 |
> |
* @since 1.7 |
24 |
> |
* @author Doug Lea |
25 |
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*/ |
26 |
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public class ForkJoinWorkerThread extends Thread { |
27 |
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/* |
45 |
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* of tasks. To accomplish this, we shift the CAS arbitrating pop |
46 |
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* vs deq (steal) from being on the indices ("base" and "sp") to |
47 |
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* the slots themselves (mainly via method "casSlotNull()"). So, |
48 |
< |
* both a successful pop and deq mainly entail CAS'ing a nonnull |
48 |
> |
* both a successful pop and deq mainly entail CAS'ing a non-null |
49 |
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* slot to null. Because we rely on CASes of references, we do |
50 |
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* not need tag bits on base or sp. They are simple ints as used |
51 |
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* in any circular array-based queue (see for example ArrayDeque). |
57 |
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* considered individually, is not wait-free. One thief cannot |
58 |
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* successfully continue until another in-progress one (or, if |
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* previously empty, a push) completes. However, in the |
60 |
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* aggregate, we ensure at least probablistic non-blockingness. If |
60 |
> |
* aggregate, we ensure at least probabilistic non-blockingness. If |
61 |
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* an attempted steal fails, a thief always chooses a different |
62 |
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* random victim target to try next. So, in order for one thief to |
63 |
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* progress, it suffices for any in-progress deq or new push on |
66 |
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* which gives threads a chance to activate if necessary before |
67 |
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* stealing (see below). |
68 |
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* |
69 |
+ |
* This approach also enables support for "async mode" where local |
70 |
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* task processing is in FIFO, not LIFO order; simply by using a |
71 |
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* version of deq rather than pop when locallyFifo is true (as set |
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* by the ForkJoinPool). This allows use in message-passing |
73 |
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* frameworks in which tasks are never joined. |
74 |
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* |
75 |
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* Efficient implementation of this approach currently relies on |
76 |
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* an uncomfortable amount of "Unsafe" mechanics. To maintain |
77 |
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* correct orderings, reads and writes of variable base require |
82 |
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* push) require store order and CASes (in pop and deq) require |
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* (volatile) CAS semantics. Since these combinations aren't |
84 |
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* supported using ordinary volatiles, the only way to accomplish |
85 |
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* these effciently is to use direct Unsafe calls. (Using external |
85 |
> |
* these efficiently is to use direct Unsafe calls. (Using external |
86 |
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* AtomicIntegers and AtomicReferenceArrays for the indices and |
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* array is significantly slower because of memory locality and |
88 |
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* indirection effects.) Further, performance on most platforms is |
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private static final int MAXIMUM_QUEUE_CAPACITY = 1 << 28; |
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|
146 |
|
/** |
147 |
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* The pool this thread works in. Accessed directly by ForkJoinTask |
147 |
> |
* The pool this thread works in. Accessed directly by ForkJoinTask. |
148 |
|
*/ |
149 |
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final ForkJoinPool pool; |
150 |
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|
172 |
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* Activity status. When true, this worker is considered active. |
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* Must be false upon construction. It must be true when executing |
174 |
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* tasks, and BEFORE stealing a task. It must be false before |
175 |
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* calling pool.sync |
175 |
> |
* calling pool.sync. |
176 |
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*/ |
177 |
|
private boolean active; |
178 |
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|
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|
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/** |
197 |
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* Index of this worker in pool array. Set once by pool before |
198 |
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* running, and accessed directly by pool during cleanup etc |
198 |
> |
* running, and accessed directly by pool during cleanup etc. |
199 |
|
*/ |
200 |
|
int poolIndex; |
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|
|
206 |
|
long lastEventCount; |
207 |
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|
208 |
|
/** |
209 |
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* True if use local fifo, not default lifo, for local polling |
210 |
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*/ |
211 |
+ |
private boolean locallyFifo; |
212 |
+ |
|
213 |
+ |
/** |
214 |
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* Creates a ForkJoinWorkerThread operating in the given pool. |
215 |
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* |
216 |
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* @param pool the pool this thread works in |
217 |
|
* @throws NullPointerException if pool is null |
218 |
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*/ |
223 |
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// Remaining initialization is deferred to onStart |
224 |
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} |
225 |
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|
226 |
< |
// Public access methods |
226 |
> |
// Public access methods |
227 |
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|
228 |
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/** |
229 |
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* Returns the pool hosting this thread |
229 |
> |
* Returns the pool hosting this thread. |
230 |
> |
* |
231 |
|
* @return the pool |
232 |
|
*/ |
233 |
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public ForkJoinPool getPool() { |
240 |
|
* threads (minus one) that have ever been created in the pool. |
241 |
|
* This method may be useful for applications that track status or |
242 |
|
* collect results per-worker rather than per-task. |
243 |
< |
* @return the index number. |
243 |
> |
* |
244 |
> |
* @return the index number |
245 |
|
*/ |
246 |
|
public int getPoolIndex() { |
247 |
|
return poolIndex; |
248 |
|
} |
249 |
|
|
250 |
+ |
/** |
251 |
+ |
* Establishes local first-in-first-out scheduling mode for forked |
252 |
+ |
* tasks that are never joined. |
253 |
+ |
* |
254 |
+ |
* @param async if true, use locally FIFO scheduling |
255 |
+ |
*/ |
256 |
+ |
void setAsyncMode(boolean async) { |
257 |
+ |
locallyFifo = async; |
258 |
+ |
} |
259 |
|
|
260 |
|
// Runstate management |
261 |
|
|
272 |
|
final boolean shutdownNow() { return transitionRunStateTo(TERMINATING); } |
273 |
|
|
274 |
|
/** |
275 |
< |
* Transition to at least the given state. Return true if not |
276 |
< |
* already at least given state. |
275 |
> |
* Transitions to at least the given state. |
276 |
> |
* |
277 |
> |
* @return {@code true} if not already at least at given state |
278 |
|
*/ |
279 |
|
private boolean transitionRunStateTo(int state) { |
280 |
|
for (;;) { |
281 |
|
int s = runState; |
282 |
|
if (s >= state) |
283 |
|
return false; |
284 |
< |
if (_unsafe.compareAndSwapInt(this, runStateOffset, s, state)) |
284 |
> |
if (UNSAFE.compareAndSwapInt(this, runStateOffset, s, state)) |
285 |
|
return true; |
286 |
|
} |
287 |
|
} |
288 |
|
|
289 |
|
/** |
290 |
< |
* Try to set status to active; fail on contention |
290 |
> |
* Tries to set status to active; fails on contention. |
291 |
|
*/ |
292 |
|
private boolean tryActivate() { |
293 |
|
if (!active) { |
299 |
|
} |
300 |
|
|
301 |
|
/** |
302 |
< |
* Try to set status to active; fail on contention |
302 |
> |
* Tries to set status to inactive; fails on contention. |
303 |
|
*/ |
304 |
|
private boolean tryInactivate() { |
305 |
|
if (active) { |
311 |
|
} |
312 |
|
|
313 |
|
/** |
314 |
< |
* Computes next value for random victim probe. Scans don't |
314 |
> |
* Computes next value for random victim probe. Scans don't |
315 |
|
* require a very high quality generator, but also not a crummy |
316 |
< |
* one. Marsaglia xor-shift is cheap and works well. |
316 |
> |
* one. Marsaglia xor-shift is cheap and works well. |
317 |
|
*/ |
318 |
|
private static int xorShift(int r) { |
319 |
< |
r ^= r << 1; |
320 |
< |
r ^= r >>> 3; |
321 |
< |
r ^= r << 10; |
297 |
< |
return r; |
319 |
> |
r ^= (r << 13); |
320 |
> |
r ^= (r >>> 17); |
321 |
> |
return r ^ (r << 5); |
322 |
|
} |
323 |
|
|
324 |
|
// Lifecycle methods |
342 |
|
} |
343 |
|
|
344 |
|
/** |
345 |
< |
* Execute tasks until shut down. |
345 |
> |
* Executes tasks until shut down. |
346 |
|
*/ |
347 |
|
private void mainLoop() { |
348 |
|
while (!isShutdown()) { |
349 |
|
ForkJoinTask<?> t = pollTask(); |
350 |
< |
if (t != null || (t = pollSubmission()) != null) |
350 |
> |
if (t != null || (t = pollSubmission()) != null) |
351 |
|
t.quietlyExec(); |
352 |
|
else if (tryInactivate()) |
353 |
|
pool.sync(this); |
374 |
|
} |
375 |
|
|
376 |
|
/** |
377 |
< |
* Perform cleanup associated with termination of this worker |
377 |
> |
* Performs cleanup associated with termination of this worker |
378 |
|
* thread. If you override this method, you must invoke |
379 |
< |
* super.onTermination at the end of the overridden method. |
379 |
> |
* {@code super.onTermination} at the end of the overridden method. |
380 |
|
* |
381 |
|
* @param exception the exception causing this thread to abort due |
382 |
< |
* to an unrecoverable error, or null if completed normally. |
382 |
> |
* to an unrecoverable error, or {@code null} if completed normally |
383 |
|
*/ |
384 |
|
protected void onTermination(Throwable exception) { |
385 |
|
// Execute remaining local tasks unless aborting or terminating |
386 |
< |
while (exception == null && !pool.isTerminating() && base != sp) { |
386 |
> |
while (exception == null && pool.isProcessingTasks() && base != sp) { |
387 |
|
try { |
388 |
|
ForkJoinTask<?> t = popTask(); |
389 |
|
if (t != null) |
390 |
|
t.quietlyExec(); |
391 |
< |
} catch(Throwable ex) { |
391 |
> |
} catch (Throwable ex) { |
392 |
|
exception = ex; |
393 |
|
} |
394 |
|
} |
395 |
|
// Cancel other tasks, transition status, notify pool, and |
396 |
|
// propagate exception to uncaught exception handler |
397 |
|
try { |
398 |
< |
do;while (!tryInactivate()); // ensure inactive |
399 |
< |
cancelTasks(); |
398 |
> |
do {} while (!tryInactivate()); // ensure inactive |
399 |
> |
cancelTasks(); |
400 |
|
runState = TERMINATED; |
401 |
|
pool.workerTerminated(this); |
402 |
|
} catch (Throwable ex) { // Shouldn't ever happen |
408 |
|
} |
409 |
|
} |
410 |
|
|
411 |
< |
// Intrinsics-based support for queue operations. |
411 |
> |
// Intrinsics-based support for queue operations. |
412 |
|
|
413 |
|
/** |
414 |
< |
* Add in store-order the given task at given slot of q to |
415 |
< |
* null. Caller must ensure q is nonnull and index is in range. |
414 |
> |
* Adds in store-order the given task at given slot of q to null. |
415 |
> |
* Caller must ensure q is non-null and index is in range. |
416 |
|
*/ |
417 |
|
private static void setSlot(ForkJoinTask<?>[] q, int i, |
418 |
< |
ForkJoinTask<?> t){ |
419 |
< |
_unsafe.putOrderedObject(q, (i << qShift) + qBase, t); |
418 |
> |
ForkJoinTask<?> t) { |
419 |
> |
UNSAFE.putOrderedObject(q, (i << qShift) + qBase, t); |
420 |
|
} |
421 |
|
|
422 |
|
/** |
423 |
< |
* CAS given slot of q to null. Caller must ensure q is nonnull |
423 |
> |
* CAS given slot of q to null. Caller must ensure q is non-null |
424 |
|
* and index is in range. |
425 |
|
*/ |
426 |
|
private static boolean casSlotNull(ForkJoinTask<?>[] q, int i, |
427 |
|
ForkJoinTask<?> t) { |
428 |
< |
return _unsafe.compareAndSwapObject(q, (i << qShift) + qBase, t, null); |
428 |
> |
return UNSAFE.compareAndSwapObject(q, (i << qShift) + qBase, t, null); |
429 |
|
} |
430 |
|
|
431 |
|
/** |
432 |
|
* Sets sp in store-order. |
433 |
|
*/ |
434 |
|
private void storeSp(int s) { |
435 |
< |
_unsafe.putOrderedInt(this, spOffset, s); |
435 |
> |
UNSAFE.putOrderedInt(this, spOffset, s); |
436 |
|
} |
437 |
|
|
438 |
|
// Main queue methods |
439 |
|
|
440 |
|
/** |
441 |
|
* Pushes a task. Called only by current thread. |
442 |
< |
* @param t the task. Caller must ensure nonnull |
442 |
> |
* |
443 |
> |
* @param t the task. Caller must ensure non-null. |
444 |
|
*/ |
445 |
|
final void pushTask(ForkJoinTask<?> t) { |
446 |
|
ForkJoinTask<?>[] q = queue; |
457 |
|
/** |
458 |
|
* Tries to take a task from the base of the queue, failing if |
459 |
|
* either empty or contended. |
460 |
< |
* @return a task, or null if none or contended. |
460 |
> |
* |
461 |
> |
* @return a task, or null if none or contended |
462 |
|
*/ |
463 |
< |
private ForkJoinTask<?> deqTask() { |
463 |
> |
final ForkJoinTask<?> deqTask() { |
464 |
|
ForkJoinTask<?> t; |
465 |
|
ForkJoinTask<?>[] q; |
466 |
|
int i; |
476 |
|
} |
477 |
|
|
478 |
|
/** |
479 |
+ |
* Tries to take a task from the base of own queue, activating if |
480 |
+ |
* necessary, failing only if empty. Called only by current thread. |
481 |
+ |
* |
482 |
+ |
* @return a task, or null if none |
483 |
+ |
*/ |
484 |
+ |
final ForkJoinTask<?> locallyDeqTask() { |
485 |
+ |
int b; |
486 |
+ |
while (sp != (b = base)) { |
487 |
+ |
if (tryActivate()) { |
488 |
+ |
ForkJoinTask<?>[] q = queue; |
489 |
+ |
int i = (q.length - 1) & b; |
490 |
+ |
ForkJoinTask<?> t = q[i]; |
491 |
+ |
if (t != null && casSlotNull(q, i, t)) { |
492 |
+ |
base = b + 1; |
493 |
+ |
return t; |
494 |
+ |
} |
495 |
+ |
} |
496 |
+ |
} |
497 |
+ |
return null; |
498 |
+ |
} |
499 |
+ |
|
500 |
+ |
/** |
501 |
|
* Returns a popped task, or null if empty. Ensures active status |
502 |
< |
* if nonnull. Called only by current thread. |
502 |
> |
* if non-null. Called only by current thread. |
503 |
|
*/ |
504 |
|
final ForkJoinTask<?> popTask() { |
505 |
|
int s = sp; |
522 |
|
* Specialized version of popTask to pop only if |
523 |
|
* topmost element is the given task. Called only |
524 |
|
* by current thread while active. |
525 |
< |
* @param t the task. Caller must ensure nonnull |
525 |
> |
* |
526 |
> |
* @param t the task. Caller must ensure non-null. |
527 |
|
*/ |
528 |
|
final boolean unpushTask(ForkJoinTask<?> t) { |
529 |
|
ForkJoinTask<?>[] q = queue; |
537 |
|
} |
538 |
|
|
539 |
|
/** |
540 |
< |
* Returns next task to pop. |
540 |
> |
* Returns next task or null if empty or contended |
541 |
|
*/ |
542 |
|
final ForkJoinTask<?> peekTask() { |
543 |
|
ForkJoinTask<?>[] q = queue; |
544 |
< |
return q == null? null : q[(sp - 1) & (q.length - 1)]; |
544 |
> |
if (q == null) |
545 |
> |
return null; |
546 |
> |
int mask = q.length - 1; |
547 |
> |
int i = locallyFifo ? base : (sp - 1); |
548 |
> |
return q[i & mask]; |
549 |
|
} |
550 |
|
|
551 |
|
/** |
607 |
|
ForkJoinWorkerThread v = ws[mask & idx]; |
608 |
|
if (v == null || v.sp == v.base) { |
609 |
|
if (probes <= mask) |
610 |
< |
idx = (probes++ < 0)? r : (idx + 1); |
610 |
> |
idx = (probes++ < 0) ? r : (idx + 1); |
611 |
|
else |
612 |
|
break; |
613 |
|
} |
623 |
|
} |
624 |
|
|
625 |
|
/** |
626 |
< |
* Pops or steals a task |
626 |
> |
* Gets and removes a local or stolen task. |
627 |
> |
* |
628 |
|
* @return a task, if available |
629 |
|
*/ |
630 |
|
final ForkJoinTask<?> pollTask() { |
631 |
< |
ForkJoinTask<?> t = popTask(); |
631 |
> |
ForkJoinTask<?> t = locallyFifo ? locallyDeqTask() : popTask(); |
632 |
|
if (t == null && (t = scan()) != null) |
633 |
|
++stealCount; |
634 |
|
return t; |
635 |
|
} |
636 |
|
|
637 |
|
/** |
638 |
+ |
* Gets a local task. |
639 |
+ |
* |
640 |
+ |
* @return a task, if available |
641 |
+ |
*/ |
642 |
+ |
final ForkJoinTask<?> pollLocalTask() { |
643 |
+ |
return locallyFifo ? locallyDeqTask() : popTask(); |
644 |
+ |
} |
645 |
+ |
|
646 |
+ |
/** |
647 |
|
* Returns a pool submission, if one exists, activating first. |
648 |
+ |
* |
649 |
|
* @return a submission, if available |
650 |
|
*/ |
651 |
|
private ForkJoinTask<?> pollSubmission() { |
671 |
|
} |
672 |
|
|
673 |
|
/** |
674 |
< |
* Get and clear steal count for accumulation by pool. Called |
674 |
> |
* Drains tasks to given collection c. |
675 |
> |
* |
676 |
> |
* @return the number of tasks drained |
677 |
> |
*/ |
678 |
> |
final int drainTasksTo(Collection<? super ForkJoinTask<?>> c) { |
679 |
> |
int n = 0; |
680 |
> |
ForkJoinTask<?> t; |
681 |
> |
while (base != sp && (t = deqTask()) != null) { |
682 |
> |
c.add(t); |
683 |
> |
++n; |
684 |
> |
} |
685 |
> |
return n; |
686 |
> |
} |
687 |
> |
|
688 |
> |
/** |
689 |
> |
* Gets and clears steal count for accumulation by pool. Called |
690 |
|
* only when known to be idle (in pool.sync and termination). |
691 |
|
*/ |
692 |
|
final int getAndClearStealCount() { |
696 |
|
} |
697 |
|
|
698 |
|
/** |
699 |
< |
* Returns true if at least one worker in the given array appears |
700 |
< |
* to have at least one queued task. |
699 |
> |
* Returns {@code true} if at least one worker in the given array |
700 |
> |
* appears to have at least one queued task. |
701 |
> |
* |
702 |
|
* @param ws array of workers |
703 |
|
*/ |
704 |
|
static boolean hasQueuedTasks(ForkJoinWorkerThread[] ws) { |
721 |
|
* Returns an estimate of the number of tasks in the queue. |
722 |
|
*/ |
723 |
|
final int getQueueSize() { |
724 |
< |
int n = sp - base; |
725 |
< |
return n < 0? 0 : n; // suppress momentarily negative values |
724 |
> |
// suppress momentarily negative values |
725 |
> |
return Math.max(0, sp - base); |
726 |
|
} |
727 |
|
|
728 |
|
/** |
735 |
|
} |
736 |
|
|
737 |
|
/** |
738 |
< |
* Scan, returning early if joinMe done |
738 |
> |
* Scans, returning early if joinMe done. |
739 |
|
*/ |
740 |
|
final ForkJoinTask<?> scanWhileJoining(ForkJoinTask<?> joinMe) { |
741 |
|
ForkJoinTask<?> t = pollTask(); |
745 |
|
} |
746 |
|
return t; |
747 |
|
} |
748 |
< |
|
748 |
> |
|
749 |
|
/** |
750 |
< |
* Runs tasks until pool isQuiescent |
750 |
> |
* Runs tasks until {@code pool.isQuiescent()}. |
751 |
|
*/ |
752 |
|
final void helpQuiescePool() { |
753 |
|
for (;;) { |
754 |
|
ForkJoinTask<?> t = pollTask(); |
755 |
< |
if (t != null) |
755 |
> |
if (t != null) |
756 |
|
t.quietlyExec(); |
757 |
|
else if (tryInactivate() && pool.isQuiescent()) |
758 |
|
break; |
759 |
|
} |
760 |
< |
do;while (!tryActivate()); // re-activate on exit |
760 |
> |
do {} while (!tryActivate()); // re-activate on exit |
761 |
|
} |
762 |
|
|
763 |
< |
// Temporary Unsafe mechanics for preliminary release |
763 |
> |
// Unsafe mechanics |
764 |
> |
|
765 |
> |
private static final sun.misc.Unsafe UNSAFE = getUnsafe(); |
766 |
> |
private static final long spOffset = |
767 |
> |
objectFieldOffset("sp", ForkJoinWorkerThread.class); |
768 |
> |
private static final long runStateOffset = |
769 |
> |
objectFieldOffset("runState", ForkJoinWorkerThread.class); |
770 |
> |
private static final long qBase; |
771 |
> |
private static final int qShift; |
772 |
|
|
685 |
– |
static final Unsafe _unsafe; |
686 |
– |
static final long baseOffset; |
687 |
– |
static final long spOffset; |
688 |
– |
static final long runStateOffset; |
689 |
– |
static final long qBase; |
690 |
– |
static final int qShift; |
773 |
|
static { |
774 |
+ |
qBase = UNSAFE.arrayBaseOffset(ForkJoinTask[].class); |
775 |
+ |
int s = UNSAFE.arrayIndexScale(ForkJoinTask[].class); |
776 |
+ |
if ((s & (s-1)) != 0) |
777 |
+ |
throw new Error("data type scale not a power of two"); |
778 |
+ |
qShift = 31 - Integer.numberOfLeadingZeros(s); |
779 |
+ |
} |
780 |
+ |
|
781 |
+ |
private static long objectFieldOffset(String field, Class<?> klazz) { |
782 |
+ |
try { |
783 |
+ |
return UNSAFE.objectFieldOffset(klazz.getDeclaredField(field)); |
784 |
+ |
} catch (NoSuchFieldException e) { |
785 |
+ |
// Convert Exception to corresponding Error |
786 |
+ |
NoSuchFieldError error = new NoSuchFieldError(field); |
787 |
+ |
error.initCause(e); |
788 |
+ |
throw error; |
789 |
+ |
} |
790 |
+ |
} |
791 |
+ |
|
792 |
+ |
/** |
793 |
+ |
* Returns a sun.misc.Unsafe. Suitable for use in a 3rd party package. |
794 |
+ |
* Replace with a simple call to Unsafe.getUnsafe when integrating |
795 |
+ |
* into a jdk. |
796 |
+ |
* |
797 |
+ |
* @return a sun.misc.Unsafe |
798 |
+ |
*/ |
799 |
+ |
private static sun.misc.Unsafe getUnsafe() { |
800 |
|
try { |
801 |
< |
if (ForkJoinWorkerThread.class.getClassLoader() != null) { |
802 |
< |
Field f = Unsafe.class.getDeclaredField("theUnsafe"); |
803 |
< |
f.setAccessible(true); |
804 |
< |
_unsafe = (Unsafe)f.get(null); |
801 |
> |
return sun.misc.Unsafe.getUnsafe(); |
802 |
> |
} catch (SecurityException se) { |
803 |
> |
try { |
804 |
> |
return java.security.AccessController.doPrivileged |
805 |
> |
(new java.security |
806 |
> |
.PrivilegedExceptionAction<sun.misc.Unsafe>() { |
807 |
> |
public sun.misc.Unsafe run() throws Exception { |
808 |
> |
java.lang.reflect.Field f = sun.misc |
809 |
> |
.Unsafe.class.getDeclaredField("theUnsafe"); |
810 |
> |
f.setAccessible(true); |
811 |
> |
return (sun.misc.Unsafe) f.get(null); |
812 |
> |
}}); |
813 |
> |
} catch (java.security.PrivilegedActionException e) { |
814 |
> |
throw new RuntimeException("Could not initialize intrinsics", |
815 |
> |
e.getCause()); |
816 |
|
} |
698 |
– |
else |
699 |
– |
_unsafe = Unsafe.getUnsafe(); |
700 |
– |
baseOffset = _unsafe.objectFieldOffset |
701 |
– |
(ForkJoinWorkerThread.class.getDeclaredField("base")); |
702 |
– |
spOffset = _unsafe.objectFieldOffset |
703 |
– |
(ForkJoinWorkerThread.class.getDeclaredField("sp")); |
704 |
– |
runStateOffset = _unsafe.objectFieldOffset |
705 |
– |
(ForkJoinWorkerThread.class.getDeclaredField("runState")); |
706 |
– |
qBase = _unsafe.arrayBaseOffset(ForkJoinTask[].class); |
707 |
– |
int s = _unsafe.arrayIndexScale(ForkJoinTask[].class); |
708 |
– |
if ((s & (s-1)) != 0) |
709 |
– |
throw new Error("data type scale not a power of two"); |
710 |
– |
qShift = 31 - Integer.numberOfLeadingZeros(s); |
711 |
– |
} catch (Exception e) { |
712 |
– |
throw new RuntimeException("Could not initialize intrinsics", e); |
817 |
|
} |
818 |
|
} |
819 |
|
} |