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package jsr166y; |
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import java.util.concurrent.*; |
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< |
import java.util.concurrent.atomic.*; |
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> |
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> |
import java.util.concurrent.atomic.AtomicReference; |
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import java.util.concurrent.locks.LockSupport; |
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import sun.misc.Unsafe; |
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import java.lang.reflect.*; |
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/** |
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* A reusable synchronization barrier, similar in functionality to a |
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* zero, and advancing when all parties reach the barrier (wrapping |
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* around to zero after reaching {@code Integer.MAX_VALUE}). |
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* |
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< |
* <li> Like a CyclicBarrier, a Phaser may be repeatedly awaited. |
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< |
* Method {@code arriveAndAwaitAdvance} has effect analogous to |
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< |
* {@code CyclicBarrier.await}. However, Phasers separate two |
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< |
* aspects of coordination, that may also be invoked independently: |
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> |
* <li> Like a {@code CyclicBarrier}, a phaser may be repeatedly |
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> |
* awaited. Method {@link #arriveAndAwaitAdvance} has effect |
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> |
* analogous to {@link java.util.concurrent.CyclicBarrier#await |
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> |
* CyclicBarrier.await}. However, phasers separate two aspects of |
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> |
* coordination, which may also be invoked independently: |
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* |
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* <ul> |
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* |
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< |
* <li> Arriving at a barrier. Methods {@code arrive} and |
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* {@code arriveAndDeregister} do not block, but return |
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> |
* <li> Arriving at a barrier. Methods {@link #arrive} and |
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> |
* {@link #arriveAndDeregister} do not block, but return |
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* the phase value current upon entry to the method. |
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* |
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< |
* <li> Awaiting others. Method {@code awaitAdvance} requires an |
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> |
* <li> Awaiting others. Method {@link #awaitAdvance} requires an |
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* argument indicating the entry phase, and returns when the |
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* barrier advances to a new phase. |
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* </ul> |
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* |
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* |
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* <li> Barrier actions, performed by the task triggering a phase |
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< |
* advance while others may be waiting, are arranged by overriding |
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< |
* method {@code onAdvance}, that also controls termination. |
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< |
* Overriding this method may be used to similar but more flexible |
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< |
* effect as providing a barrier action to a CyclicBarrier. |
| 54 |
> |
* advance, are arranged by overriding method {@link #onAdvance(int, |
| 55 |
> |
* int)}, which also controls termination. Overriding this method is |
| 56 |
> |
* similar to, but more flexible than, providing a barrier action to a |
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> |
* {@code CyclicBarrier}. |
| 58 |
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* |
| 59 |
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* <li> Phasers may enter a <em>termination</em> state in which all |
| 60 |
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* actions immediately return without updating phaser state or waiting |
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* for advance, and indicating (via a negative phase value) that |
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< |
* execution is complete. Termination is triggered by executing the |
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< |
* overridable {@code onAdvance} method that is invoked each time the |
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< |
* barrier is about to be tripped. When a Phaser is controlling an |
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< |
* action with a fixed number of iterations, it is often convenient to |
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< |
* override this method to cause termination when the current phase |
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< |
* number reaches a threshold. Method {@code forceTermination} is also |
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< |
* available to abruptly release waiting threads and allow them to |
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< |
* terminate. |
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> |
* execution is complete. Termination is triggered when an invocation |
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> |
* of {@code onAdvance} returns {@code true}. When a phaser is |
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> |
* controlling an action with a fixed number of iterations, it is |
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> |
* often convenient to override this method to cause termination when |
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> |
* the current phase number reaches a threshold. Method {@link |
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> |
* #forceTermination} is also available to abruptly release waiting |
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> |
* threads and allow them to terminate. |
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* |
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* <li> Phasers may be tiered to reduce contention. Phasers with large |
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* numbers of parties that would otherwise experience heavy |
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* |
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* <li> By default, {@code awaitAdvance} continues to wait even if |
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* the waiting thread is interrupted. And unlike the case in |
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< |
* CyclicBarriers, exceptions encountered while tasks wait |
| 78 |
> |
* {@code CyclicBarrier}, exceptions encountered while tasks wait |
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* interruptibly or with timeout do not change the state of the |
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* barrier. If necessary, you can perform any associated recovery |
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* within handlers of those exceptions, often after invoking |
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* {@code forceTermination}. |
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* |
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< |
* <li>Phasers ensure lack of starvation when used by ForkJoinTasks. |
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> |
* <li>Phasers may be used to coordinate tasks executing in a {@link |
| 85 |
> |
* ForkJoinPool}, which will ensure sufficient parallelism to execute |
| 86 |
> |
* tasks when others are blocked waiting for a phase to advance. |
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* |
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* </ul> |
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* |
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* <p><b>Sample usages:</b> |
| 91 |
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* |
| 92 |
< |
* <p>A Phaser may be used instead of a {@code CountDownLatch} to control |
| 93 |
< |
* a one-shot action serving a variable number of parties. The typical |
| 94 |
< |
* idiom is for the method setting this up to first register, then |
| 95 |
< |
* start the actions, then deregister, as in: |
| 92 |
> |
* <p>A {@code Phaser} may be used instead of a {@code CountDownLatch} |
| 93 |
> |
* to control a one-shot action serving a variable number of |
| 94 |
> |
* parties. The typical idiom is for the method setting this up to |
| 95 |
> |
* first register, then start the actions, then deregister, as in: |
| 96 |
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* |
| 97 |
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* <pre> {@code |
| 98 |
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* void runTasks(List<Runnable> list) { |
| 99 |
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* final Phaser phaser = new Phaser(1); // "1" to register self |
| 100 |
+ |
* // create and start threads |
| 101 |
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* for (Runnable r : list) { |
| 102 |
|
* phaser.register(); |
| 103 |
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* new Thread() { |
| 104 |
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* public void run() { |
| 105 |
|
* phaser.arriveAndAwaitAdvance(); // await all creation |
| 106 |
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* r.run(); |
| 105 |
– |
* phaser.arriveAndDeregister(); // signal completion |
| 107 |
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* } |
| 108 |
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* }.start(); |
| 109 |
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* } |
| 110 |
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* |
| 111 |
< |
* doSomethingOnBehalfOfWorkers(); |
| 112 |
< |
* phaser.arrive(); // allow threads to start |
| 112 |
< |
* int p = phaser.arriveAndDeregister(); // deregister self ... |
| 113 |
< |
* p = phaser.awaitAdvance(p); // ... and await arrival |
| 114 |
< |
* otherActions(); // do other things while tasks execute |
| 115 |
< |
* phaser.awaitAdvance(p); // await final completion |
| 111 |
> |
* // allow threads to start and deregister self |
| 112 |
> |
* phaser.arriveAndDeregister(); |
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* }}</pre> |
| 114 |
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* |
| 115 |
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* <p>One way to cause a set of threads to repeatedly perform actions |
| 137 |
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* phaser.arriveAndDeregister(); // deregister self, don't wait |
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* }}</pre> |
| 139 |
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* |
| 140 |
< |
* <p> To create a set of tasks using a tree of Phasers, |
| 140 |
> |
* <p>To create a set of tasks using a tree of phasers, |
| 141 |
|
* you could use code of the following form, assuming a |
| 142 |
< |
* Task class with a constructor accepting a Phaser that |
| 142 |
> |
* Task class with a constructor accepting a phaser that |
| 143 |
|
* it registers for upon construction: |
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* <pre> {@code |
| 145 |
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* void build(Task[] actions, int lo, int hi, Phaser b) { |
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* |
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* <p><b>Implementation notes</b>: This implementation restricts the |
| 171 |
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* maximum number of parties to 65535. Attempts to register additional |
| 172 |
< |
* parties result in IllegalStateExceptions. However, you can and |
| 172 |
> |
* parties result in {@code IllegalStateException}. However, you can and |
| 173 |
|
* should create tiered phasers to accommodate arbitrarily large sets |
| 174 |
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* of participants. |
| 175 |
|
* |
| 208 |
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private static final int phaseMask = 0x7fffffff; |
| 209 |
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|
| 210 |
|
private static int unarrivedOf(long s) { |
| 211 |
< |
return (int)(s & ushortMask); |
| 211 |
> |
return (int) (s & ushortMask); |
| 212 |
|
} |
| 213 |
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|
| 214 |
|
private static int partiesOf(long s) { |
| 215 |
< |
return ((int)s) >>> 16; |
| 215 |
> |
return ((int) s) >>> 16; |
| 216 |
|
} |
| 217 |
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|
| 218 |
|
private static int phaseOf(long s) { |
| 219 |
< |
return (int)(s >>> 32); |
| 219 |
> |
return (int) (s >>> 32); |
| 220 |
|
} |
| 221 |
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|
| 222 |
|
private static int arrivedOf(long s) { |
| 224 |
|
} |
| 225 |
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|
| 226 |
|
private static long stateFor(int phase, int parties, int unarrived) { |
| 227 |
< |
return ((((long)phase) << 32) | (((long)parties) << 16) | |
| 228 |
< |
(long)unarrived); |
| 227 |
> |
return ((((long) phase) << 32) | (((long) parties) << 16) | |
| 228 |
> |
(long) unarrived); |
| 229 |
|
} |
| 230 |
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|
| 231 |
|
private static long trippedStateFor(int phase, int parties) { |
| 232 |
< |
long lp = (long)parties; |
| 233 |
< |
return (((long)phase) << 32) | (lp << 16) | lp; |
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> |
long lp = (long) parties; |
| 233 |
> |
return (((long) phase) << 32) | (lp << 16) | lp; |
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} |
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|
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/** |
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private final Phaser parent; |
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|
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/** |
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< |
* The root of Phaser tree. Equals this if not in a tree. Used to |
| 250 |
> |
* The root of phaser tree. Equals this if not in a tree. Used to |
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* support faster state push-down. |
| 252 |
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*/ |
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private final Phaser root; |
| 263 |
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private final AtomicReference<QNode> oddQ = new AtomicReference<QNode>(); |
| 264 |
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|
| 265 |
|
private AtomicReference<QNode> queueFor(int phase) { |
| 266 |
< |
return (phase & 1) == 0? evenQ : oddQ; |
| 266 |
> |
return ((phase & 1) == 0) ? evenQ : oddQ; |
| 267 |
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} |
| 268 |
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|
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/** |
| 271 |
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* root if necessary. |
| 272 |
|
*/ |
| 273 |
|
private long getReconciledState() { |
| 274 |
< |
return parent == null? state : reconcileState(); |
| 274 |
> |
return (parent == null) ? state : reconcileState(); |
| 275 |
|
} |
| 276 |
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|
| 277 |
|
/** |
| 298 |
|
} |
| 299 |
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|
| 300 |
|
/** |
| 301 |
< |
* Creates a new Phaser without any initially registered parties, |
| 301 |
> |
* Creates a new phaser without any initially registered parties, |
| 302 |
|
* initial phase number 0, and no parent. Any thread using this |
| 303 |
< |
* Phaser will need to first register for it. |
| 303 |
> |
* phaser will need to first register for it. |
| 304 |
|
*/ |
| 305 |
|
public Phaser() { |
| 306 |
|
this(null); |
| 307 |
|
} |
| 308 |
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|
| 309 |
|
/** |
| 310 |
< |
* Creates a new Phaser with the given numbers of registered |
| 310 |
> |
* Creates a new phaser with the given numbers of registered |
| 311 |
|
* unarrived parties, initial phase number 0, and no parent. |
| 312 |
|
* |
| 313 |
|
* @param parties the number of parties required to trip barrier |
| 319 |
|
} |
| 320 |
|
|
| 321 |
|
/** |
| 322 |
< |
* Creates a new Phaser with the given parent, without any |
| 322 |
> |
* Creates a new phaser with the given parent, without any |
| 323 |
|
* initially registered parties. If parent is non-null this phaser |
| 324 |
|
* is registered with the parent and its initial phase number is |
| 325 |
|
* the same as that of parent phaser. |
| 339 |
|
} |
| 340 |
|
|
| 341 |
|
/** |
| 342 |
< |
* Creates a new Phaser with the given parent and numbers of |
| 342 |
> |
* Creates a new phaser with the given parent and numbers of |
| 343 |
|
* registered unarrived parties. If parent is non-null, this phaser |
| 344 |
|
* is registered with the parent and its initial phase number is |
| 345 |
|
* the same as that of parent phaser. |
| 438 |
|
if (par == null) { // directly trip |
| 439 |
|
if (casState |
| 440 |
|
(s, |
| 441 |
< |
trippedStateFor(onAdvance(phase, parties)? -1 : |
| 441 |
> |
trippedStateFor(onAdvance(phase, parties) ? -1 : |
| 442 |
|
((phase + 1) & phaseMask), parties))) { |
| 443 |
|
releaseWaiters(phase); |
| 444 |
|
break; |
| 461 |
|
} |
| 462 |
|
|
| 463 |
|
/** |
| 464 |
< |
* Arrives at the barrier, and deregisters from it, without |
| 465 |
< |
* waiting for others. Deregistration reduces number of parties |
| 464 |
> |
* Arrives at the barrier and deregisters from it without waiting |
| 465 |
> |
* for others. Deregistration reduces the number of parties |
| 466 |
|
* required to trip the barrier in future phases. If this phaser |
| 467 |
|
* has a parent, and deregistration causes this phaser to have |
| 468 |
< |
* zero parties, this phaser is also deregistered from its parent. |
| 468 |
> |
* zero parties, this phaser also arrives at and is deregistered |
| 469 |
> |
* from its parent. |
| 470 |
|
* |
| 471 |
|
* @return the current barrier phase number upon entry to |
| 472 |
|
* this method, or a negative value if terminated |
| 500 |
|
if (unarrived == 0) { |
| 501 |
|
if (casState |
| 502 |
|
(s, |
| 503 |
< |
trippedStateFor(onAdvance(phase, parties)? -1 : |
| 503 |
> |
trippedStateFor(onAdvance(phase, parties) ? -1 : |
| 504 |
|
((phase + 1) & phaseMask), parties))) { |
| 505 |
|
releaseWaiters(phase); |
| 506 |
|
break; |
| 519 |
|
|
| 520 |
|
/** |
| 521 |
|
* Arrives at the barrier and awaits others. Equivalent in effect |
| 522 |
< |
* to {@code awaitAdvance(arrive())}. If you instead need to |
| 523 |
< |
* await with interruption of timeout, and/or deregister upon |
| 524 |
< |
* arrival, you can arrange them using analogous constructions. |
| 522 |
> |
* to {@code awaitAdvance(arrive())}. If you need to await with |
| 523 |
> |
* interruption or timeout, you can arrange this with an analogous |
| 524 |
> |
* construction using one of the other forms of the awaitAdvance |
| 525 |
> |
* method. If instead you need to deregister upon arrival use |
| 526 |
> |
* {@code arriveAndDeregister}. |
| 527 |
|
* |
| 528 |
|
* @return the phase on entry to this method |
| 529 |
|
* @throws IllegalStateException if not terminated and the number |
| 534 |
|
} |
| 535 |
|
|
| 536 |
|
/** |
| 537 |
< |
* Awaits the phase of the barrier to advance from the given |
| 538 |
< |
* value, or returns immediately if argument is negative or this |
| 539 |
< |
* barrier is terminated. |
| 537 |
> |
* Awaits the phase of the barrier to advance from the given phase |
| 538 |
> |
* value, returning immediately if the current phase of the |
| 539 |
> |
* barrier is not equal to the given phase value or this barrier |
| 540 |
> |
* is terminated. |
| 541 |
|
* |
| 542 |
|
* @param phase the phase on entry to this method |
| 543 |
|
* @return the phase on exit from this method |
| 556 |
|
} |
| 557 |
|
|
| 558 |
|
/** |
| 559 |
< |
* Awaits the phase of the barrier to advance from the given |
| 560 |
< |
* value, or returns immediately if argument is negative or this |
| 561 |
< |
* barrier is terminated, or throws InterruptedException if |
| 562 |
< |
* interrupted while waiting. |
| 559 |
> |
* Awaits the phase of the barrier to advance from the given phase |
| 560 |
> |
* value, throwing {@code InterruptedException} if interrupted while |
| 561 |
> |
* waiting, or returning immediately if the current phase of the |
| 562 |
> |
* barrier is not equal to the given phase value or this barrier |
| 563 |
> |
* is terminated. |
| 564 |
|
* |
| 565 |
|
* @param phase the phase on entry to this method |
| 566 |
|
* @return the phase on exit from this method |
| 580 |
|
} |
| 581 |
|
|
| 582 |
|
/** |
| 583 |
< |
* Awaits the phase of the barrier to advance from the given value |
| 584 |
< |
* or the given timeout elapses, or returns immediately if |
| 585 |
< |
* argument is negative or this barrier is terminated. |
| 583 |
> |
* Awaits the phase of the barrier to advance from the given phase |
| 584 |
> |
* value or the given timeout to elapse, throwing |
| 585 |
> |
* {@code InterruptedException} if interrupted while waiting, or |
| 586 |
> |
* returning immediately if the current phase of the barrier is not |
| 587 |
> |
* equal to the given phase value or this barrier is terminated. |
| 588 |
|
* |
| 589 |
|
* @param phase the phase on entry to this method |
| 590 |
+ |
* @param timeout how long to wait before giving up, in units of |
| 591 |
+ |
* {@code unit} |
| 592 |
+ |
* @param unit a {@code TimeUnit} determining how to interpret the |
| 593 |
+ |
* {@code timeout} parameter |
| 594 |
|
* @return the phase on exit from this method |
| 595 |
|
* @throws InterruptedException if thread interrupted while waiting |
| 596 |
|
* @throws TimeoutException if timed out while waiting |
| 597 |
|
*/ |
| 598 |
< |
public int awaitAdvanceInterruptibly(int phase, long timeout, TimeUnit unit) |
| 598 |
> |
public int awaitAdvanceInterruptibly(int phase, |
| 599 |
> |
long timeout, TimeUnit unit) |
| 600 |
|
throws InterruptedException, TimeoutException { |
| 601 |
|
if (phase < 0) |
| 602 |
|
return phase; |
| 645 |
|
} |
| 646 |
|
|
| 647 |
|
/** |
| 639 |
– |
* Returns {@code true} if the current phase number equals the given phase. |
| 640 |
– |
* |
| 641 |
– |
* @param phase the phase |
| 642 |
– |
* @return {@code true} if the current phase number equals the given phase |
| 643 |
– |
*/ |
| 644 |
– |
public final boolean hasPhase(int phase) { |
| 645 |
– |
return phaseOf(getReconciledState()) == phase; |
| 646 |
– |
} |
| 647 |
– |
|
| 648 |
– |
/** |
| 648 |
|
* Returns the number of parties registered at this barrier. |
| 649 |
|
* |
| 650 |
|
* @return the number of parties |
| 674 |
|
} |
| 675 |
|
|
| 676 |
|
/** |
| 677 |
< |
* Returns the parent of this phaser, or null if none. |
| 677 |
> |
* Returns the parent of this phaser, or {@code null} if none. |
| 678 |
|
* |
| 679 |
< |
* @return the parent of this phaser, or null if none |
| 679 |
> |
* @return the parent of this phaser, or {@code null} if none |
| 680 |
|
*/ |
| 681 |
|
public Phaser getParent() { |
| 682 |
|
return parent; |
| 705 |
|
* Overridable method to perform an action upon phase advance, and |
| 706 |
|
* to control termination. This method is invoked whenever the |
| 707 |
|
* barrier is tripped (and thus all other waiting parties are |
| 708 |
< |
* dormant). If it returns true, then, rather than advance the |
| 709 |
< |
* phase number, this barrier will be set to a final termination |
| 710 |
< |
* state, and subsequent calls to {@code isTerminated} will |
| 711 |
< |
* return true. |
| 708 |
> |
* dormant). If it returns {@code true}, then, rather than advance |
| 709 |
> |
* the phase number, this barrier will be set to a final |
| 710 |
> |
* termination state, and subsequent calls to {@link #isTerminated} |
| 711 |
> |
* will return true. |
| 712 |
|
* |
| 713 |
< |
* <p> The default version returns true when the number of |
| 713 |
> |
* <p>The default version returns {@code true} when the number of |
| 714 |
|
* registered parties is zero. Normally, overrides that arrange |
| 715 |
|
* termination for other reasons should also preserve this |
| 716 |
|
* property. |
| 717 |
|
* |
| 718 |
< |
* <p> You may override this method to perform an action with side |
| 718 |
> |
* <p>You may override this method to perform an action with side |
| 719 |
|
* effects visible to participating tasks, but it is in general |
| 720 |
|
* only sensible to do so in designs where all parties register |
| 721 |
< |
* before any arrive, and all {@code awaitAdvance} at each phase. |
| 722 |
< |
* Otherwise, you cannot ensure lack of interference. In |
| 723 |
< |
* particular, this method may be invoked more than once per |
| 725 |
< |
* transition if other parties successfully register while the |
| 726 |
< |
* invocation of this method is in progress, thus postponing the |
| 727 |
< |
* transition until those parties also arrive, re-triggering this |
| 728 |
< |
* method. |
| 721 |
> |
* before any arrive, and all {@link #awaitAdvance} at each phase. |
| 722 |
> |
* Otherwise, you cannot ensure lack of interference from other |
| 723 |
> |
* parties during the invocation of this method. |
| 724 |
|
* |
| 725 |
|
* @param phase the phase number on entering the barrier |
| 726 |
|
* @param registeredParties the current number of registered parties |
| 925 |
|
return p; |
| 926 |
|
} |
| 927 |
|
|
| 928 |
< |
// Temporary Unsafe mechanics for preliminary release |
| 934 |
< |
private static Unsafe getUnsafe() throws Throwable { |
| 935 |
< |
try { |
| 936 |
< |
return Unsafe.getUnsafe(); |
| 937 |
< |
} catch (SecurityException se) { |
| 938 |
< |
try { |
| 939 |
< |
return java.security.AccessController.doPrivileged |
| 940 |
< |
(new java.security.PrivilegedExceptionAction<Unsafe>() { |
| 941 |
< |
public Unsafe run() throws Exception { |
| 942 |
< |
return getUnsafePrivileged(); |
| 943 |
< |
}}); |
| 944 |
< |
} catch (java.security.PrivilegedActionException e) { |
| 945 |
< |
throw e.getCause(); |
| 946 |
< |
} |
| 947 |
< |
} |
| 948 |
< |
} |
| 928 |
> |
// Unsafe mechanics |
| 929 |
|
|
| 930 |
< |
private static Unsafe getUnsafePrivileged() |
| 931 |
< |
throws NoSuchFieldException, IllegalAccessException { |
| 932 |
< |
Field f = Unsafe.class.getDeclaredField("theUnsafe"); |
| 953 |
< |
f.setAccessible(true); |
| 954 |
< |
return (Unsafe) f.get(null); |
| 955 |
< |
} |
| 930 |
> |
private static final sun.misc.Unsafe UNSAFE = getUnsafe(); |
| 931 |
> |
private static final long stateOffset = |
| 932 |
> |
objectFieldOffset("state", Phaser.class); |
| 933 |
|
|
| 934 |
< |
private static long fieldOffset(String fieldName) |
| 935 |
< |
throws NoSuchFieldException { |
| 959 |
< |
return UNSAFE.objectFieldOffset |
| 960 |
< |
(Phaser.class.getDeclaredField(fieldName)); |
| 934 |
> |
private final boolean casState(long cmp, long val) { |
| 935 |
> |
return UNSAFE.compareAndSwapLong(this, stateOffset, cmp, val); |
| 936 |
|
} |
| 937 |
|
|
| 938 |
< |
static final Unsafe UNSAFE; |
| 964 |
< |
static final long stateOffset; |
| 965 |
< |
|
| 966 |
< |
static { |
| 938 |
> |
private static long objectFieldOffset(String field, Class<?> klazz) { |
| 939 |
|
try { |
| 940 |
< |
UNSAFE = getUnsafe(); |
| 941 |
< |
stateOffset = fieldOffset("state"); |
| 942 |
< |
} catch (Throwable e) { |
| 943 |
< |
throw new RuntimeException("Could not initialize intrinsics", e); |
| 940 |
> |
return UNSAFE.objectFieldOffset(klazz.getDeclaredField(field)); |
| 941 |
> |
} catch (NoSuchFieldException e) { |
| 942 |
> |
// Convert Exception to corresponding Error |
| 943 |
> |
NoSuchFieldError error = new NoSuchFieldError(field); |
| 944 |
> |
error.initCause(e); |
| 945 |
> |
throw error; |
| 946 |
|
} |
| 947 |
|
} |
| 948 |
|
|
| 949 |
< |
final boolean casState(long cmp, long val) { |
| 950 |
< |
return UNSAFE.compareAndSwapLong(this, stateOffset, cmp, val); |
| 949 |
> |
/** |
| 950 |
> |
* Returns a sun.misc.Unsafe. Suitable for use in a 3rd party package. |
| 951 |
> |
* Replace with a simple call to Unsafe.getUnsafe when integrating |
| 952 |
> |
* into a jdk. |
| 953 |
> |
* |
| 954 |
> |
* @return a sun.misc.Unsafe |
| 955 |
> |
*/ |
| 956 |
> |
private static sun.misc.Unsafe getUnsafe() { |
| 957 |
> |
try { |
| 958 |
> |
return sun.misc.Unsafe.getUnsafe(); |
| 959 |
> |
} catch (SecurityException se) { |
| 960 |
> |
try { |
| 961 |
> |
return java.security.AccessController.doPrivileged |
| 962 |
> |
(new java.security |
| 963 |
> |
.PrivilegedExceptionAction<sun.misc.Unsafe>() { |
| 964 |
> |
public sun.misc.Unsafe run() throws Exception { |
| 965 |
> |
java.lang.reflect.Field f = sun.misc |
| 966 |
> |
.Unsafe.class.getDeclaredField("theUnsafe"); |
| 967 |
> |
f.setAccessible(true); |
| 968 |
> |
return (sun.misc.Unsafe) f.get(null); |
| 969 |
> |
}}); |
| 970 |
> |
} catch (java.security.PrivilegedActionException e) { |
| 971 |
> |
throw new RuntimeException("Could not initialize intrinsics", |
| 972 |
> |
e.getCause()); |
| 973 |
> |
} |
| 974 |
> |
} |
| 975 |
|
} |
| 976 |
|
} |
