| 86 |
|
* #forceTermination} is also available to abruptly release waiting |
| 87 |
|
* threads and allow them to terminate. |
| 88 |
|
* |
| 89 |
< |
* <p> <b>Tiering.</b> Phasers may be <em>tiered</em> (i.e., arranged |
| 90 |
< |
* in tree structures) to reduce contention. Phasers with large |
| 91 |
< |
* numbers of parties that would otherwise experience heavy |
| 89 |
> |
* <p> <b>Tiering.</b> Phasers may be <em>tiered</em> (i.e., |
| 90 |
> |
* constructed in tree structures) to reduce contention. Phasers with |
| 91 |
> |
* large numbers of parties that would otherwise experience heavy |
| 92 |
|
* synchronization contention costs may instead be set up so that |
| 93 |
|
* groups of sub-phasers share a common parent. This may greatly |
| 94 |
|
* increase throughput even though it incurs greater per-operation |
| 353 |
|
/** |
| 354 |
|
* Implementation of register, bulkRegister |
| 355 |
|
* |
| 356 |
< |
* @param registrations number to add to both parties and unarrived fields |
| 356 |
> |
* @param registrations number to add to both parties and |
| 357 |
> |
* unarrived fields. Must be greater than zero. |
| 358 |
|
*/ |
| 359 |
|
private int doRegister(int registrations) { |
| 359 |
– |
// assert registrations > 0; |
| 360 |
|
// adjustment to state |
| 361 |
|
long adj = ((long)registrations << PARTIES_SHIFT) | registrations; |
| 362 |
|
final Phaser parent = this.parent; |
| 363 |
|
for (;;) { |
| 364 |
|
long s = (parent == null) ? state : reconcileState(); |
| 365 |
+ |
int parties = (int)s >>> PARTIES_SHIFT; |
| 366 |
|
int phase = (int)(s >>> PHASE_SHIFT); |
| 367 |
|
if (phase < 0) |
| 368 |
|
return phase; |
| 369 |
< |
int parties = (int)s >>> PARTIES_SHIFT; |
| 369 |
< |
if (parties != 0 && ((int)s & UNARRIVED_MASK) == 0) |
| 369 |
> |
else if (parties != 0 && ((int)s & UNARRIVED_MASK) == 0) |
| 370 |
|
internalAwaitAdvance(phase, null); // wait for onAdvance |
| 371 |
|
else if (registrations > MAX_PARTIES - parties) |
| 372 |
|
throw new IllegalStateException(badRegister(s)); |
| 433 |
|
} |
| 434 |
|
|
| 435 |
|
/** |
| 436 |
< |
* Creates a new phaser with the given parent, without any |
| 437 |
< |
* initially registered parties. If parent is non-null this phaser |
| 438 |
< |
* is registered with the parent and its initial phase number is |
| 439 |
< |
* the same as that of parent phaser. |
| 436 |
> |
* Equivalent to {@link #Phaser(Phaser, int) Phaser(parent, 0)}. |
| 437 |
|
* |
| 438 |
|
* @param parent the parent phaser |
| 439 |
|
*/ |
| 443 |
|
|
| 444 |
|
/** |
| 445 |
|
* Creates a new phaser with the given parent and number of |
| 446 |
< |
* registered unarrived parties. If parent is non-null, this phaser |
| 447 |
< |
* is registered with the parent and its initial phase number is |
| 448 |
< |
* the same as that of parent phaser. |
| 446 |
> |
* registered unarrived parties. If parent is non-null, this |
| 447 |
> |
* phaser is registered with the parent and its initial phase |
| 448 |
> |
* number is the same as that of parent phaser. If the number of |
| 449 |
> |
* parties is zero, the parent phaser will not proceed until this |
| 450 |
> |
* child phaser registers parties and advances, or this child |
| 451 |
> |
* phaser deregisters with its parent, or the parent is otherwise |
| 452 |
> |
* terminated. This child Phaser will be deregistered from its |
| 453 |
> |
* parent automatically upon any invocation of the child's {@link |
| 454 |
> |
* #arriveAndDeregister} method that results in the child's number |
| 455 |
> |
* of registered parties becoming zero. (Although rarely |
| 456 |
> |
* appropriate, this child may also explicity deregister from its |
| 457 |
> |
* parent using {@code getParent().arriveAndDeregister()}.) After |
| 458 |
> |
* deregistration, the child cannot re-register. (Instead, you can |
| 459 |
> |
* create a new child Phaser.) |
| 460 |
|
* |
| 461 |
|
* @param parent the parent phaser |
| 462 |
|
* @param parties the number of parties required to trip barrier |
| 473 |
|
this.root = r; |
| 474 |
|
this.evenQ = r.evenQ; |
| 475 |
|
this.oddQ = r.oddQ; |
| 476 |
< |
phase = parent.register(); |
| 476 |
> |
phase = parent.doRegister(1); |
| 477 |
|
} |
| 478 |
|
else { |
| 479 |
|
this.root = this; |
