Robust/src/Benchmarks/Prefetch/SOR/dsm/SORRunner.java

   1 /**************************************************************************
   2  *                                                                         *
   3  *         Java Grande Forum Benchmark Suite - Thread Version 1.0          *
   4  *                                                                         *
   5  *                            produced by                                  *
   6  *                                                                         *
   7  *                  Java Grande Benchmarking Project                       *
   8  *                                                                         *
   9  *                                at                                       *
  10  *                                                                         *
  11  *                Edinburgh Parallel Computing Centre                      *
  12  *                                                                         *
  13  *                email: epcc-javagrande@epcc.ed.ac.uk                     *
  14  *                                                                         *
  15  *      adapted from SciMark 2.0, author Roldan Pozo (pozo@cam.nist.gov)   *
  16  *                                                                         *
  17  *      This version copyright (c) The University of Edinburgh, 2001.      *
  18  *                         All rights reserved.                            *
  19  *                                                                         *
  20  **************************************************************************/
  21
  22 class SORRunner extends Thread {
  23
  24   int id,num_iterations;
  25   double G[][],omega;
  26   long sync[][];
  27   int nthreads;
  28
  29   public SORRunner(int id, double omega, double G[][], int num_iterations,long[][] sync, int nthreads) {
  30     this.id = id;
  31     this.omega=omega;
  32     this.G=G;
  33     this.num_iterations=num_iterations;
  34     this.sync=sync;
  35     this.nthreads = nthreads;
  36   }
  37
  38   public void run() {
  39
  40     int tmpid, M, N, numthreads;
  41     double omega_over_four, one_minus_omega;
  42     atomic {
  43       M = G.length;
  44       N = G[0].length;
  45       omega_over_four = omega * 0.25;
  46       one_minus_omega = 1.0 - omega;
  47       numthreads = nthreads;
  48       tmpid = id;
  49     }
  50
  51     // update interior points
  52     //
  53     int Mm1 = M-1;
  54     int Nm1 = N-1;
  55
  56
  57     int ilow, iupper, slice, tslice, ttslice;
  58
  59     tslice = (Mm1) / 2;
  60     ttslice = (tslice + numthreads-1)/numthreads;
  61     slice = ttslice*2;
  62     ilow=tmpid*slice+1;
  63     iupper = ((tmpid+1)*slice)+1;
  64     if (iupper > Mm1) iupper =  Mm1+1;
  65     if (tmpid == (numthreads-1)) iupper = Mm1+1;
  66
  67     atomic {
  68       for (int p=0; p<2*num_iterations; p++) {
  69         for (int i=ilow+(p%2); i<iupper; i=i+2) {
  70
  71           double [] Gi = G[i];
  72           double [] Gim1 = G[i-1];
  73
  74           if(i == 1) {
  75             double [] Gip1 = G[i+1];
  76
  77             for (int j=1; j<Nm1; j=j+2){
  78               Gi[j] = omega_over_four * (Gim1[j] + Gip1[j] + Gi[j-1]
  79                   + Gi[j+1]) + one_minus_omega * Gi[j];
  80
  81             }
  82           } else if (i == Mm1) {
  83
  84             double [] Gim2 = G[i-2];
  85
  86             for (int j=1; j<Nm1; j=j+2){
  87               if((j+1) != Nm1) {
  88                 Gim1[j+1]=omega_over_four * (Gim2[j+1] + Gi[j+1] + Gim1[j]
  89                     + Gim1[j+2]) + one_minus_omega * Gim1[j+1];
  90               }
  91             }
  92
  93           } else {
  94
  95             double [] Gip1 = G[i+1];
  96             double [] Gim2 = G[i-2];
  97
  98             for (int j=1; j<Nm1; j=j+2){
  99               Gi[j] = omega_over_four * (Gim1[j] + Gip1[j] + Gi[j-1]
 100                   + Gi[j+1]) + one_minus_omega * Gi[j];
 101
 102               if((j+1) != Nm1) {
 103                 Gim1[j+1]=omega_over_four * (Gim2[j+1] + Gi[j+1] + Gim1[j]
 104                     + Gim1[j+2]) + one_minus_omega * Gim1[j+1];
 105               }
 106             }
 107           }
 108
 109         }
 110
 111         // Signal this thread has done iteration
 112         sync[id][0]++;
 113
 114         // Wait for neighbours;
 115         if (id > 0) {
 116           while (sync[id-1][0] < sync[id][0]) ;
 117         }
 118         if (id < nthreads -1) {
 119           while (sync[id+1][0] < sync[id][0]) ;
 120         }
 121       }//end of outer for
 122     }//end of atomic
 123   }//end of run
 124 }