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root/jsr166/jsr166/src/jsr166y/ForkJoinWorkerThread.java
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Comparing jsr166/src/jsr166y/ForkJoinWorkerThread.java (file contents):
Revision 1.45 by jsr166, Sat Sep 4 00:08:04 2010 UTC vs.
Revision 1.46 by dl, Sat Sep 4 11:33:53 2010 UTC

# Line 172 | Line 172 | public class ForkJoinWorkerThread extend
172  
173      /**
174       * Maximum work-stealing queue array size.  Must be less than or
175 <     * equal to 1 << 28 to ensure lack of index wraparound. (This
176 <     * is less than usual bounds, because we need leftshift by 3
177 <     * to be in int range).
175 >     * equal to 1 << (31 - width of array entry) to ensure lack of
176 >     * index wraparound. The value is set in the static block
177 >     * at the end of this file after obtaining width.
178       */
179 <    private static final int MAXIMUM_QUEUE_CAPACITY = 1 << 28;
179 >    private static final int MAXIMUM_QUEUE_CAPACITY;
180  
181      /**
182       * The pool this thread works in. Accessed directly by ForkJoinTask.
# Line 230 | Line 230 | public class ForkJoinWorkerThread extend
230      private static final int TRIMMED     = 0x08; // killed while suspended
231  
232      /**
233 <     * Number of steals, transferred and reset in pool callbacks pool
234 <     * when idle Accessed directly by pool.
233 >     * Number of steals. Directly accessed (and reset) by
234 >     * pool.tryAccumulateStealCount when idle.
235       */
236      int stealCount;
237  
# Line 286 | Line 286 | public class ForkJoinWorkerThread extend
286  
287      /**
288       * The task currently being joined, set only when actively trying
289 <     * to helpStealer. Written only by current thread, but read by
290 <     * others.
289 >     * to help other stealers in helpJoinTask. Written only by this
290 >     * thread, but read by others.
291       */
292      private volatile ForkJoinTask<?> currentJoin;
293  
294      /**
295       * The task most recently stolen from another worker (or
296 <     * submission queue).  Written only by current thread, but read by
296 >     * submission queue).  Written only by this thread, but read by
297       * others.
298       */
299      private volatile ForkJoinTask<?> currentSteal;
# Line 349 | Line 349 | public class ForkJoinWorkerThread extend
349      /**
350       * Initializes internal state after construction but before
351       * processing any tasks. If you override this method, you must
352 <     * invoke super.onStart() at the beginning of the method.
352 >     * invoke @code{super.onStart()} at the beginning of the method.
353       * Initialization requires care: Most fields must have legal
354       * default values, to ensure that attempted accesses from other
355       * threads work correctly even before this thread starts
# Line 447 | Line 447 | public class ForkJoinWorkerThread extend
447      }
448  
449      /**
450 <     * If a submission exists, try to activate and run it;
450 >     * If a submission exists, try to activate and run it.
451       *
452       * @return true if ran a task
453       */
454      private boolean tryExecSubmission() {
455          ForkJoinPool p = pool;
456 +        // This loop is needed in case attempt to activate fails, in
457 +        // which case we only retry if there still appears to be a
458 +        // submission.
459          while (p.hasQueuedSubmissions()) {
460              ForkJoinTask<?> t; int a;
461              if (active || // inline p.tryIncrementActiveCount
# Line 562 | Line 565 | public class ForkJoinWorkerThread extend
565  
566      /**
567       * Tries to take a task from the base of own queue. Assumes active
568 <     * status.  Called only by current thread.
568 >     * status.  Called only by this thread.
569       *
570       * @return a task, or null if none
571       */
# Line 585 | Line 588 | public class ForkJoinWorkerThread extend
588  
589      /**
590       * Returns a popped task, or null if empty. Assumes active status.
591 <     * Called only by current thread.
591 >     * Called only by this thread.
592       */
593      private ForkJoinTask<?> popTask() {
594          ForkJoinTask<?>[] q = queue;
# Line 609 | Line 612 | public class ForkJoinWorkerThread extend
612  
613      /**
614       * Specialized version of popTask to pop only if topmost element
615 <     * is the given task. Called only by current thread while
613 <     * active.
615 >     * is the given task. Called only by this thread while active.
616       *
617       * @param t the task. Caller must ensure non-null.
618       */
# Line 1055 | Line 1057 | public class ForkJoinWorkerThread extend
1057      }
1058  
1059      /**
1060 +     * Implements ForJoinTask.getSurplusQueuedTaskCount().
1061       * Returns an estimate of the number of tasks, offset by a
1062       * function of number of idle workers.
1063       *
# Line 1157 | Line 1160 | public class ForkJoinWorkerThread extend
1160          if ((s & (s-1)) != 0)
1161              throw new Error("data type scale not a power of two");
1162          qShift = 31 - Integer.numberOfLeadingZeros(s);
1163 +        MAXIMUM_QUEUE_CAPACITY = 1 << (31 - qShift);
1164      }
1165  
1166      private static long objectFieldOffset(String field, Class<?> klazz) {

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