blitz_stable: src/EDU/oswego/cs/dl/util/concurrent/FJTaskRunner.java annotate

annotate src/EDU/oswego/cs/dl/util/concurrent/FJTaskRunner.java @ 27:511648fa4d64 Version 2.1

Version to 2.1

author	Dan Creswell <dan.creswell@gmail.com>
date	Mon, 04 Jan 2010 13:00:40 +0000
parents	3dc0c5604566
children

rev	line source
0 3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	1 /*
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	2 File: FJTaskRunner.java
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	3
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	4 Originally written by Doug Lea and released into the public domain.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	5 This may be used for any purposes whatsoever without acknowledgment.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	6 Thanks for the assistance and support of Sun Microsystems Labs,
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	7 and everyone contributing, testing, and using this code.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	8
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	9 History:
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	10 Date Who What
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	11 7Jan1999 dl First public release
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	12 13Jan1999 dl correct a stat counter update;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	13 ensure inactive status on run termination;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	14 misc minor cleaup
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	15 14Jan1999 dl Use random starting point in scan;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	16 variable renamings.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	17 18Jan1999 dl Runloop allowed to die on task exception;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	18 remove useless timed join
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	19 22Jan1999 dl Rework scan to allow use of priorities.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	20 6Feb1999 dl Documentation updates.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	21 7Mar1999 dl Add array-based coInvoke
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	22 31Mar1999 dl Revise scan to remove need for NullTasks
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	23 27Apr1999 dl Renamed
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	24 23oct1999 dl Earlier detect of interrupt in scanWhileIdling
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	25 24nov1999 dl Now works on JVMs that do not properly
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	26 implement read-after-write of 2 volatiles.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	27 */
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	28
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	29 package EDU.oswego.cs.dl.util.concurrent;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	30
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	31 import java.util.Random;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	32
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	33 /**
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	34 * Specialized Thread subclass for running FJTasks.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	35 * <p>
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	36 * Each FJTaskRunner keeps FJTasks in a double-ended queue (DEQ).
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	37 * Double-ended queues support stack-based operations
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	38 * push and pop, as well as queue-based operations put and take.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	39 * Normally, threads run their own tasks. But they
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	40 * may also steal tasks from each others DEQs.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	41 * <p>
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	42 * The algorithms are minor variants of those used
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	43 * in <A href="http://supertech.lcs.mit.edu/cilk/"> Cilk</A> and
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	44 * <A href="http://www.cs.utexas.edu/users/hood/"> Hood</A>, and
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	45 * to a lesser extent
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	46 * <A href="http://www.cs.uga.edu/~dkl/filaments/dist.html"> Filaments</A>,
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	47 * but are adapted to work in Java.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	48 * <p>
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	49 * The two most important capabilities are:
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	50 * <ul>
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	51 * <li> Fork a FJTask:
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	52 * <pre>
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	53 * Push task onto DEQ
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	54 * </pre>
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	55 * <li> Get a task to run (for example within taskYield)
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	56 * <pre>
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	57 * If DEQ is not empty,
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	58 * Pop a task and run it.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	59 * Else if any other DEQ is not empty,
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	60 * Take ("steal") a task from it and run it.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	61 * Else if the entry queue for our group is not empty,
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	62 * Take a task from it and run it.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	63 * Else if current thread is otherwise idling
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	64 * If all threads are idling
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	65 * Wait for a task to be put on group entry queue
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	66 * Else
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	67 * Yield or Sleep for a while, and then retry
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	68 * </pre>
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	69 * </ul>
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	70 * The push, pop, and put are designed to only ever called by the
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	71 * current thread, and take (steal) is only ever called by
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	72 * other threads.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	73 * All other operations are composites and variants of these,
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	74 * plus a few miscellaneous bookkeeping methods.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	75 * <p>
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	76 * Implementations of the underlying representations and operations
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	77 * are geared for use on JVMs operating on multiple CPUs (although
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	78 * they should of course work fine on single CPUs as well).
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	79 * <p>
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	80 * A possible snapshot of a FJTaskRunner's DEQ is:
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	81 * <pre>
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	82 * 0 1 2 3 4 5 6 ...
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	83 * +-----+-----+-----+-----+-----+-----+-----+--
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	84 * \| \| t \| t \| t \| t \| \| \| ... deq array
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	85 * +-----+-----+-----+-----+-----+-----+-----+--
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	86 * ^ ^
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	87 * base top
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	88 * (incremented (incremented
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	89 * on take, on push
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	90 * decremented decremented
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	91 * on put) on pop)
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	92 * </pre>
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	93 * <p>
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	94 * FJTasks are held in elements of the DEQ.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	95 * They are maintained in a bounded array that
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	96 * works similarly to a circular bounded buffer. To ensure
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	97 * visibility of stolen FJTasks across threads, the array elements
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	98 * must be <code>volatile</code>.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	99 * Using volatile rather than synchronizing suffices here since
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	100 * each task accessed by a thread is either one that it
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	101 * created or one that has never seen before. Thus we cannot
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	102 * encounter any staleness problems executing run methods,
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	103 * although FJTask programmers must be still sure to either synch or use
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	104 * volatile for shared data within their run methods.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	105 * <p>
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	106 * However, since there is no way
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	107 * to declare an array of volatiles in Java, the DEQ elements actually
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	108 * hold VolatileTaskRef objects, each of which in turn holds a
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	109 * volatile reference to a FJTask.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	110 * Even with the double-indirection overhead of
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	111 * volatile refs, using an array for the DEQ works out
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	112 * better than linking them since fewer shared
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	113 * memory locations need to be
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	114 * touched or modified by the threads while using the DEQ.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	115 * Further, the double indirection may alleviate cache-line
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	116 * sharing effects (which cannot otherwise be directly dealt with in Java).
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	117 * <p>
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	118 * The indices for the <code>base</code> and <code>top</code> of the DEQ
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	119 * are declared as volatile. The main contention point with
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	120 * multiple FJTaskRunner threads occurs when one thread is trying
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	121 * to pop its own stack while another is trying to steal from it.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	122 * This is handled via a specialization of Dekker's algorithm,
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	123 * in which the popping thread pre-decrements <code>top</code>,
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	124 * and then checks it against <code>base</code>.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	125 * To be conservative in the face of JVMs that only partially
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	126 * honor the specification for volatile, the pop proceeds
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	127 * without synchronization only if there are apparently enough
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	128 * items for both a simultaneous pop and take to succeed.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	129 * It otherwise enters a
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	130 * synchronized lock to check if the DEQ is actually empty,
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	131 * if so failing. The stealing thread
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	132 * does almost the opposite, but is set up to be less likely
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	133 * to win in cases of contention: Steals always run under synchronized
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	134 * locks in order to avoid conflicts with other ongoing steals.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	135 * They pre-increment <code>base</code>, and then check against
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	136 * <code>top</code>. They back out (resetting the base index
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	137 * and failing to steal) if the
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	138 * DEQ is empty or is about to become empty by an ongoing pop.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	139 * <p>
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	140 * A push operation can normally run concurrently with a steal.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	141 * A push enters a synch lock only if the DEQ appears full so must
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	142 * either be resized or have indices adjusted due to wrap-around
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	143 * of the bounded DEQ. The put operation always requires synchronization.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	144 * <p>
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	145 * When a FJTaskRunner thread has no tasks of its own to run,
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	146 * it tries to be a good citizen.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	147 * Threads run at lower priority while scanning for work.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	148 * <p>
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	149 * If the task is currently waiting
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	150 * via yield, the thread alternates scans (starting at a randomly
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	151 * chosen victim) with Thread.yields. This is
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	152 * well-behaved so long as the JVM handles Thread.yield in a
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	153 * sensible fashion. (It need not. Thread.yield is so underspecified
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	154 * that it is legal for a JVM to treat it as a no-op.) This also
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	155 * keeps things well-behaved even if we are running on a uniprocessor
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	156 * JVM using a simple cooperative threading model.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	157 * <p>
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	158 * If a thread needing work is
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	159 * is otherwise idle (which occurs only in the main runloop), and
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	160 * there are no available tasks to steal or poll, it
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	161 * instead enters into a sleep-based (actually timed wait(msec))
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	162 * phase in which it progressively sleeps for longer durations
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	163 * (up to a maximum of FJTaskRunnerGroup.MAX_SLEEP_TIME,
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	164 * currently 100ms) between scans.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	165 * If all threads in the group
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	166 * are idling, they further progress to a hard wait phase, suspending
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	167 * until a new task is entered into the FJTaskRunnerGroup entry queue.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	168 * A sleeping FJTaskRunner thread may be awakened by a new
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	169 * task being put into the group entry queue or by another FJTaskRunner
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	170 * becoming active, but not merely by some DEQ becoming non-empty.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	171 * Thus the MAX_SLEEP_TIME provides a bound for sleep durations
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	172 * in cases where all but one worker thread start sleeping
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	173 * even though there will eventually be work produced
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	174 * by a thread that is taking a long time to place tasks in DEQ.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	175 * These sleep mechanics are handled in the FJTaskRunnerGroup class.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	176 * <p>
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	177 * Composite operations such as taskJoin include heavy
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	178 * manual inlining of the most time-critical operations
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	179 * (mainly FJTask.invoke).
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	180 * This opens up a few opportunities for further hand-optimizations.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	181 * Until Java compilers get a lot smarter, these tweaks
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	182 * improve performance significantly enough for task-intensive
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	183 * programs to be worth the poorer maintainability and code duplication.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	184 * <p>
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	185 * Because they are so fragile and performance-sensitive, nearly
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	186 * all methods are declared as final. However, nearly all fields
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	187 * and methods are also declared as protected, so it is possible,
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	188 * with much care, to extend functionality in subclasses. (Normally
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	189 * you would also need to subclass FJTaskRunnerGroup.)
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	190 * <p>
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	191 * None of the normal java.lang.Thread class methods should ever be called
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	192 * on FJTaskRunners. For this reason, it might have been nicer to
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	193 * declare FJTaskRunner as a Runnable to run within a Thread. However,
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	194 * this would have complicated many minor logistics. And since
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	195 * no FJTaskRunner methods should normally be called from outside the
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	196 * FJTask and FJTaskRunnerGroup classes either, this decision doesn't impact
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	197 * usage.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	198 * <p>
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	199 * You might think that layering this kind of framework on top of
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	200 * Java threads, which are already several levels removed from raw CPU
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	201 * scheduling on most systems, would lead to very poor performance.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	202 * But on the platforms
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	203 * tested, the performance is quite good.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	204 * <p>[<a href="http://gee.cs.oswego.edu/dl/classes/EDU/oswego/cs/dl/util/concurrent/intro.html"> Introduction to this package. </a>]
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	205 * @see FJTask
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	206 * @see FJTaskRunnerGroup
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	207 **/
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	208
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	209 public class FJTaskRunner extends Thread {
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	210
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	211 / The group of which this FJTaskRunner is a member /
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	212 protected final FJTaskRunnerGroup group;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	213
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	214 /**
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	215 * Constructor called only during FJTaskRunnerGroup initialization
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	216 **/
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	217
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	218 protected FJTaskRunner(FJTaskRunnerGroup g) {
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	219 group = g;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	220 victimRNG = new Random(System.identityHashCode(this));
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	221 runPriority = getPriority();
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	222 setDaemon(true);
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	223 }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	224
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	225 /**
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	226 * Return the FJTaskRunnerGroup of which this thread is a member
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	227 **/
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	228
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	229 protected final FJTaskRunnerGroup getGroup() { return group; }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	230
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	231
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	232 /* ------------ DEQ Representation ------------------- */
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	233
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	234
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	235 /**
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	236 * FJTasks are held in an array-based DEQ with INITIAL_CAPACITY
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	237 * elements. The DEQ is grown if necessary, but default value is
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	238 * normally much more than sufficient unless there are
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	239 * user programming errors or questionable operations generating
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	240 * large numbers of Tasks without running them.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	241 * Capacities must be a power of two.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	242 **/
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	243
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	244 protected static final int INITIAL_CAPACITY = 4096;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	245
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	246 /**
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	247 * The maximum supported DEQ capacity.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	248 * When exceeded, FJTaskRunner operations throw Errors
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	249 **/
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	250
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	251 protected static final int MAX_CAPACITY = 1 << 30;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	252
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	253 /**
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	254 * An object holding a single volatile reference to a FJTask.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	255 **/
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	256
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	257 protected final static class VolatileTaskRef {
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	258 / The reference /
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	259 protected volatile FJTask ref;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	260
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	261 / Set the reference /
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	262 protected final void put(FJTask r) { ref = r; }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	263 / Return the reference /
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	264 protected final FJTask get() { return ref; }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	265 / Return the reference and clear it /
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	266 protected final FJTask take() { FJTask r = ref; ref = null; return r; }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	267
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	268 /**
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	269 * Initialization utility for constructing arrays.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	270 * Make an array of given capacity and fill it with
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	271 * VolatileTaskRefs.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	272 **/
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	273 protected static VolatileTaskRef[] newArray(int cap) {
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	274 VolatileTaskRef[] a = new VolatileTaskRef[cap];
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	275 for (int k = 0; k < cap; k++) a[k] = new VolatileTaskRef();
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	276 return a;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	277 }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	278
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	279 }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	280
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	281 /**
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	282 * The DEQ array.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	283 **/
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	284
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	285 protected VolatileTaskRef[] deq = VolatileTaskRef.newArray(INITIAL_CAPACITY);
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	286
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	287 / Current size of the task DEQ /
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	288 protected int deqSize() { return deq.length; }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	289
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	290 /**
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	291 * Current top of DEQ. Generally acts just like a stack pointer in an
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	292 * array-based stack, except that it circularly wraps around the
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	293 * array, as in an array-based queue. The value is NOT
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	294 * always kept within <code>0 ... deq.length</code> though.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	295 * The current top element is always at <code>top & (deq.length-1)</code>.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	296 * To avoid integer overflow, top is reset down
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	297 * within bounds whenever it is noticed to be out out bounds;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	298 * at worst when it is at <code>2 * deq.length</code>.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	299 **/
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	300 protected volatile int top = 0;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	301
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	302
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	303 /**
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	304 * Current base of DEQ. Acts like a take-pointer in an
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	305 * array-based bounded queue. Same bounds and usage as top.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	306 **/
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	307
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	308 protected volatile int base = 0;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	309
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	310
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	311 /**
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	312 * An extra object to synchronize on in order to
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	313 * achieve a memory barrier.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	314 **/
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	315
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	316 protected final Object barrier = new Object();
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	317
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	318 /* ------------ Other BookKeeping ------------------- */
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	319
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	320 /**
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	321 * Record whether current thread may be processing a task
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	322 * (i.e., has been started and is not in an idle wait).
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	323 * Accessed, under synch, ONLY by FJTaskRunnerGroup, but the field is
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	324 * stored here for simplicity.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	325 **/
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	326
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	327 protected boolean active = false;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	328
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	329 / Random starting point generator for scan() /
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	330 protected final Random victimRNG;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	331
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	332
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	333 / Priority to use while scanning for work /
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	334 protected int scanPriority = FJTaskRunnerGroup.DEFAULT_SCAN_PRIORITY;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	335
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	336 / Priority to use while running tasks /
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	337 protected int runPriority;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	338
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	339 /**
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	340 * Set the priority to use while scanning.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	341 * We do not bother synchronizing access, since
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	342 * by the time the value is needed, both this FJTaskRunner
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	343 * and its FJTaskRunnerGroup will
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	344 * necessarily have performed enough synchronization
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	345 * to avoid staleness problems of any consequence.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	346 **/
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	347 protected void setScanPriority(int pri) { scanPriority = pri; }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	348
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	349
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	350 /**
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	351 * Set the priority to use while running tasks.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	352 * Same usage and rationale as setScanPriority.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	353 **/
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	354 protected void setRunPriority(int pri) { runPriority = pri; }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	355
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	356 /**
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	357 * Compile-time constant for statistics gathering.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	358 * Even when set, reported values may not be accurate
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	359 * since all are read and written without synchronization.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	360 **/
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	361
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	362
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	363
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	364 static final boolean COLLECT_STATS = true;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	365 // static final boolean COLLECT_STATS = false;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	366
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	367
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	368 // for stat collection
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	369
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	370 / Total number of tasks run /
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	371 protected int runs = 0;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	372
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	373 / Total number of queues scanned for work /
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	374 protected int scans = 0;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	375
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	376 / Total number of tasks obtained via scan /
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	377 protected int steals = 0;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	378
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	379
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	380
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	381
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	382 /* ------------ DEQ operations ------------------- */
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	383
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	384
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	385 /**
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	386 * Push a task onto DEQ.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	387 * Called ONLY by current thread.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	388 **/
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	389
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	390 protected final void push(final FJTask r) {
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	391 int t = top;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	392
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	393 /*
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	394 This test catches both overflows and index wraps. It doesn't
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	395 really matter if base value is in the midst of changing in take.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	396 As long as deq length is < 2^30, we are guaranteed to catch wrap in
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	397 time since base can only be incremented at most length times
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	398 between pushes (or puts).
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	399 */
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	400
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	401 if (t < (base & (deq.length-1)) + deq.length) {
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	402
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	403 deq[t & (deq.length-1)].put(r);
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	404 top = t + 1;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	405 }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	406
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	407 else // isolate slow case to increase chances push is inlined
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	408 slowPush(r); // check overflow and retry
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	409 }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	410
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	411
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	412 /**
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	413 * Handle slow case for push
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	414 **/
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	415
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	416 protected synchronized void slowPush(final FJTask r) {
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	417 checkOverflow();
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	418 push(r); // just recurse -- this one is sure to succeed.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	419 }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	420
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	421
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	422 /**
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	423 * Enqueue task at base of DEQ.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	424 * Called ONLY by current thread.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	425 * This method is currently not called from class FJTask. It could be used
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	426 * as a faster way to do FJTask.start, but most users would
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	427 * find the semantics too confusing and unpredictable.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	428 **/
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	429
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	430 protected final synchronized void put(final FJTask r) {
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	431 for (;;) {
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	432 int b = base - 1;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	433 if (top < b + deq.length) {
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	434
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	435 int newBase = b & (deq.length-1);
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	436 deq[newBase].put(r);
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	437 base = newBase;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	438
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	439 if (b != newBase) { // Adjust for index underflow
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	440 int newTop = top & (deq.length-1);
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	441 if (newTop < newBase) newTop += deq.length;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	442 top = newTop;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	443 }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	444 return;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	445 }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	446 else {
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	447 checkOverflow();
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	448 // ... and retry
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	449 }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	450 }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	451 }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	452
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	453 /**
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	454 * Return a popped task, or null if DEQ is empty.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	455 * Called ONLY by current thread.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	456 * <p>
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	457 * This is not usually called directly but is
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	458 * instead inlined in callers. This version differs from the
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	459 * cilk algorithm in that pop does not fully back down and
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	460 * retry in the case of potential conflict with take. It simply
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	461 * rechecks under synch lock. This gives a preference
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	462 * for threads to run their own tasks, which seems to
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	463 * reduce flailing a bit when there are few tasks to run.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	464 **/
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	465
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	466 protected final FJTask pop() {
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	467 /*
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	468 Decrement top, to force a contending take to back down.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	469 */
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	470
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	471 int t = --top;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	472
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	473 /*
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	474 To avoid problems with JVMs that do not properly implement
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	475 read-after-write of a pair of volatiles, we conservatively
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	476 grab without lock only if the DEQ appears to have at least two
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	477 elements, thus guaranteeing that both a pop and take will succeed,
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	478 even if the pre-increment in take is not seen by current thread.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	479 Otherwise we recheck under synch.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	480 */
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	481
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	482 if (base + 1 < t)
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	483 return deq[t & (deq.length-1)].take();
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	484 else
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	485 return confirmPop(t);
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	486
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	487 }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	488
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	489
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	490 /**
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	491 * Check under synch lock if DEQ is really empty when doing pop.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	492 * Return task if not empty, else null.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	493 **/
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	494
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	495 protected final synchronized FJTask confirmPop(int provisionalTop) {
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	496 if (base <= provisionalTop)
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	497 return deq[provisionalTop & (deq.length-1)].take();
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	498 else { // was empty
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	499 /*
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	500 Reset DEQ indices to zero whenever it is empty.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	501 This both avoids unnecessary calls to checkOverflow
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	502 in push, and helps keep the DEQ from accumulating garbage
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	503 */
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	504
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	505 top = base = 0;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	506 return null;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	507 }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	508 }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	509
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	510
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	511 /**
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	512 * Take a task from the base of the DEQ.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	513 * Always called by other threads via scan()
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	514 **/
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	515
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	516
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	517 protected final synchronized FJTask take() {
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	518
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	519 /*
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	520 Increment base in order to suppress a contending pop
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	521 */
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	522
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	523 int b = base++;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	524
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	525 if (b < top)
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	526 return confirmTake(b);
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	527 else {
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	528 // back out
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	529 base = b;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	530 return null;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	531 }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	532 }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	533
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	534
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	535 /**
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	536 * double-check a potential take
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	537 **/
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	538
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	539 protected FJTask confirmTake(int oldBase) {
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	540
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	541 /*
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	542 Use a second (guaranteed uncontended) synch
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	543 to serve as a barrier in case JVM does not
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	544 properly process read-after-write of 2 volatiles
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	545 */
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	546
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	547 synchronized(barrier) {
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	548 if (oldBase < top) {
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	549 /*
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	550 We cannot call deq[oldBase].take here because of possible races when
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	551 nulling out versus concurrent push operations. Resulting
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	552 accumulated garbage is swept out periodically in
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	553 checkOverflow, or more typically, just by keeping indices
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	554 zero-based when found to be empty in pop, which keeps active
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	555 region small and constantly overwritten.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	556 */
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	557
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	558 return deq[oldBase & (deq.length-1)].get();
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	559 }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	560 else {
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	561 base = oldBase;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	562 return null;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	563 }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	564 }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	565 }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	566
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	567
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	568 /**
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	569 * Adjust top and base, and grow DEQ if necessary.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	570 * Called only while DEQ synch lock being held.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	571 * We don't expect this to be called very often. In most
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	572 * programs using FJTasks, it is never called.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	573 **/
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	574
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	575 protected void checkOverflow() {
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	576 int t = top;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	577 int b = base;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	578
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	579 if (t - b < deq.length-1) { // check if just need an index reset
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	580
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	581 int newBase = b & (deq.length-1);
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	582 int newTop = top & (deq.length-1);
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	583 if (newTop < newBase) newTop += deq.length;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	584 top = newTop;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	585 base = newBase;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	586
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	587 /*
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	588 Null out refs to stolen tasks.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	589 This is the only time we can safely do it.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	590 */
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	591
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	592 int i = newBase;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	593 while (i != newTop && deq[i].ref != null) {
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	594 deq[i].ref = null;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	595 i = (i - 1) & (deq.length-1);
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	596 }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	597
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	598 }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	599 else { // grow by doubling array
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	600
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	601 int newTop = t - b;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	602 int oldcap = deq.length;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	603 int newcap = oldcap * 2;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	604
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	605 if (newcap >= MAX_CAPACITY)
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	606 throw new Error("FJTask queue maximum capacity exceeded");
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	607
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	608 VolatileTaskRef[] newdeq = new VolatileTaskRef[newcap];
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	609
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	610 // copy in bottom half of new deq with refs from old deq
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	611 for (int j = 0; j < oldcap; ++j) newdeq[j] = deq[b++ & (oldcap-1)];
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	612
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	613 // fill top half of new deq with new refs
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	614 for (int j = oldcap; j < newcap; ++j) newdeq[j] = new VolatileTaskRef();
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	615
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	616 deq = newdeq;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	617 base = 0;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	618 top = newTop;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	619 }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	620 }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	621
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	622
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	623 /* ------------ Scheduling ------------------- */
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	624
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	625
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	626 /**
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	627 * Do all but the pop() part of yield or join, by
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	628 * traversing all DEQs in our group looking for a task to
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	629 * steal. If none, it checks the entry queue.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	630 * <p>
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	631 * Since there are no good, portable alternatives,
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	632 * we rely here on a mixture of Thread.yield and priorities
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	633 * to reduce wasted spinning, even though these are
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	634 * not well defined. We are hoping here that the JVM
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	635 * does something sensible.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	636 * @param waitingFor if non-null, the current task being joined
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	637 **/
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	638
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	639 protected void scan(final FJTask waitingFor) {
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	640
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	641 FJTask task = null;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	642
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	643 // to delay lowering priority until first failure to steal
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	644 boolean lowered = false;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	645
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	646 /*
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	647 Circularly traverse from a random start index.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	648
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	649 This differs slightly from cilk version that uses a random index
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	650 for each attempted steal.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	651 Exhaustive scanning might impede analytic tractablity of
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	652 the scheduling policy, but makes it much easier to deal with
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	653 startup and shutdown.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	654 */
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	655
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	656 FJTaskRunner[] ts = group.getArray();
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	657 int idx = victimRNG.nextInt(ts.length);
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	658
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	659 for (int i = 0; i < ts.length; ++i) {
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	660
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	661 FJTaskRunner t = ts[idx];
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	662 if (++idx >= ts.length) idx = 0; // circularly traverse
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	663
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	664 if (t != null && t != this) {
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	665
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	666 if (waitingFor != null && waitingFor.isDone()) {
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	667 break;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	668 }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	669 else {
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	670 if (COLLECT_STATS) ++scans;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	671 task = t.take();
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	672 if (task != null) {
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	673 if (COLLECT_STATS) ++steals;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	674 break;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	675 }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	676 else if (isInterrupted()) {
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	677 break;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	678 }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	679 else if (!lowered) { // if this is first fail, lower priority
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	680 lowered = true;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	681 setPriority(scanPriority);
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	682 }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	683 else { // otherwise we are at low priority; just yield
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	684 yield();
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	685 }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	686 }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	687 }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	688
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	689 }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	690
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	691 if (task == null) {
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	692 if (COLLECT_STATS) ++scans;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	693 task = group.pollEntryQueue();
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	694 if (COLLECT_STATS) if (task != null) ++steals;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	695 }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	696
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	697 if (lowered) setPriority(runPriority);
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	698
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	699 if (task != null && !task.isDone()) {
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	700 if (COLLECT_STATS) ++runs;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	701 task.run();
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	702 task.setDone();
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	703 }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	704
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	705 }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	706
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	707 /**
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	708 * Same as scan, but called when current thread is idling.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	709 * It repeatedly scans other threads for tasks,
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	710 * sleeping while none are available.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	711 * <p>
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	712 * This differs from scan mainly in that
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	713 * since there is no reason to return to recheck any
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	714 * condition, we iterate until a task is found, backing
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	715 * off via sleeps if necessary.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	716 **/
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	717
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	718 protected void scanWhileIdling() {
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	719 FJTask task = null;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	720
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	721 boolean lowered = false;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	722 long iters = 0;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	723
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	724 FJTaskRunner[] ts = group.getArray();
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	725 int idx = victimRNG.nextInt(ts.length);
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	726
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	727 do {
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	728 for (int i = 0; i < ts.length; ++i) {
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	729
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	730 FJTaskRunner t = ts[idx];
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	731 if (++idx >= ts.length) idx = 0; // circularly traverse
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	732
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	733 if (t != null && t != this) {
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	734 if (COLLECT_STATS) ++scans;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	735
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	736 task = t.take();
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	737 if (task != null) {
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	738 if (COLLECT_STATS) ++steals;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	739 if (lowered) setPriority(runPriority);
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	740 group.setActive(this);
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	741 break;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	742 }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	743 }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	744 }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	745
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	746 if (task == null) {
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	747 if (isInterrupted())
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	748 return;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	749
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	750 if (COLLECT_STATS) ++scans;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	751 task = group.pollEntryQueue();
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	752
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	753 if (task != null) {
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	754 if (COLLECT_STATS) ++steals;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	755 if (lowered) setPriority(runPriority);
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	756 group.setActive(this);
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	757 }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	758 else {
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	759 ++iters;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	760 // Check here for yield vs sleep to avoid entering group synch lock
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	761 if (iters >= group.SCANS_PER_SLEEP) {
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	762 group.checkActive(this, iters);
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	763 if (isInterrupted())
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	764 return;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	765 }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	766 else if (!lowered) {
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	767 lowered = true;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	768 setPriority(scanPriority);
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	769 }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	770 else {
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	771 yield();
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	772 }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	773 }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	774 }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	775 } while (task == null);
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	776
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	777
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	778 if (!task.isDone()) {
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	779 if (COLLECT_STATS) ++runs;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	780 task.run();
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	781 task.setDone();
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	782 }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	783
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	784 }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	785
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	786 /* ------------ composite operations ------------------- */
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	787
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	788
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	789 /**
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	790 * Main runloop
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	791 **/
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	792
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	793 public void run() {
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	794 try{
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	795 while (!interrupted()) {
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	796
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	797 FJTask task = pop();
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	798 if (task != null) {
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	799 if (!task.isDone()) {
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	800 // inline FJTask.invoke
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	801 if (COLLECT_STATS) ++runs;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	802 task.run();
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	803 task.setDone();
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	804 }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	805 }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	806 else
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	807 scanWhileIdling();
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	808 }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	809 }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	810 finally {
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	811 group.setInactive(this);
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	812 }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	813 }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	814
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	815 /**
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	816 * Execute a task in this thread. Generally called when current task
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	817 * cannot otherwise continue.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	818 **/
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	819
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	820
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	821 protected final void taskYield() {
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	822 FJTask task = pop();
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	823 if (task != null) {
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	824 if (!task.isDone()) {
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	825 if (COLLECT_STATS) ++runs;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	826 task.run();
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	827 task.setDone();
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	828 }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	829 }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	830 else
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	831 scan(null);
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	832 }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	833
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	834
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	835 /**
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	836 * Process tasks until w is done.
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	837 * Equivalent to <code>while(!w.isDone()) taskYield(); </code>
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	838 **/
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	839
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	840 protected final void taskJoin(final FJTask w) {
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	841
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	842 while (!w.isDone()) {
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	843
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	844 FJTask task = pop();
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	845 if (task != null) {
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	846 if (!task.isDone()) {
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	847 if (COLLECT_STATS) ++runs;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	848 task.run();
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	849 task.setDone();
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	850 if (task == w) return; // fast exit if we just ran w
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	851 }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	852 }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	853 else
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	854 scan(w);
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	855 }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	856 }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	857
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	858 /**
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	859 * A specialized expansion of
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	860 * <code> w.fork(); invoke(v); w.join(); </code>
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	861 **/
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	862
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	863
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	864 protected final void coInvoke(final FJTask w, final FJTask v) {
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	865
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	866 // inline push
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	867
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	868 int t = top;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	869 if (t < (base & (deq.length-1)) + deq.length) {
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	870
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	871 deq[t & (deq.length-1)].put(w);
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	872 top = t + 1;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	873
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	874 // inline invoke
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	875
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	876 if (!v.isDone()) {
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	877 if (COLLECT_STATS) ++runs;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	878 v.run();
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	879 v.setDone();
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	880 }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	881
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	882 // inline taskJoin
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	883
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	884 while (!w.isDone()) {
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	885 FJTask task = pop();
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	886 if (task != null) {
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	887 if (!task.isDone()) {
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	888 if (COLLECT_STATS) ++runs;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	889 task.run();
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	890 task.setDone();
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	891 if (task == w) return; // fast exit if we just ran w
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	892 }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	893 }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	894 else
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	895 scan(w);
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	896 }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	897 }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	898
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	899 else // handle non-inlinable cases
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	900 slowCoInvoke(w, v);
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	901 }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	902
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	903
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	904 /**
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	905 * Backup to handle noninlinable cases of coInvoke
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	906 **/
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	907
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	908 protected void slowCoInvoke(final FJTask w, final FJTask v) {
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	909 push(w); // let push deal with overflow
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	910 FJTask.invoke(v);
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	911 taskJoin(w);
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	912 }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	913
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	914
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	915 /**
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	916 * Array-based version of coInvoke
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	917 **/
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	918
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	919 protected final void coInvoke(FJTask[] tasks) {
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	920 int nforks = tasks.length - 1;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	921
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	922 // inline bulk push of all but one task
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	923
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	924 int t = top;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	925
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	926 if (nforks >= 0 && t + nforks < (base & (deq.length-1)) + deq.length) {
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	927 for (int i = 0; i < nforks; ++i) {
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	928 deq[t++ & (deq.length-1)].put(tasks[i]);
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	929 top = t;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	930 }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	931
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	932 // inline invoke of one task
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	933 FJTask v = tasks[nforks];
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	934 if (!v.isDone()) {
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	935 if (COLLECT_STATS) ++runs;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	936 v.run();
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	937 v.setDone();
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	938 }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	939
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	940 // inline taskJoins
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	941
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	942 for (int i = 0; i < nforks; ++i) {
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	943 FJTask w = tasks[i];
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	944 while (!w.isDone()) {
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	945
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	946 FJTask task = pop();
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	947 if (task != null) {
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	948 if (!task.isDone()) {
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	949 if (COLLECT_STATS) ++runs;
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	950 task.run();
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	951 task.setDone();
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	952 }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	953 }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	954 else
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	955 scan(w);
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	956 }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	957 }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	958 }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	959
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	960 else // handle non-inlinable cases
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	961 slowCoInvoke(tasks);
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	962 }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	963
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	964 /**
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	965 * Backup to handle atypical or noninlinable cases of coInvoke
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	966 **/
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	967
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	968 protected void slowCoInvoke(FJTask[] tasks) {
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	969 for (int i = 0; i < tasks.length; ++i) push(tasks[i]);
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	970 for (int i = 0; i < tasks.length; ++i) taskJoin(tasks[i]);
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	971 }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	972
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	973 }
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet. Dan Creswell <dan.creswell@gmail.com> parents: diff changeset	974

Mercurial > hg > blitz_stable

annotate src/EDU/oswego/cs/dl/util/concurrent/FJTaskRunner.java @ 27:511648fa4d64 Version 2.1