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1 /******************************************************************************
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2 * FILE: omp_workshare1.c
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3 * DESCRIPTION:
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4 * OpenMP Example - Loop Work-sharing - C/C++ Version
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5 * In this example, the iterations of a loop are scheduled dynamically
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6 * across the team of threads. A thread will perform CHUNK iterations
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7 * at a time before being scheduled for the next CHUNK of work.
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8 * AUTHOR: Blaise Barney 5/99
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9 * LAST REVISED: 04/06/05
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10 ******************************************************************************/
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11 #include <omp.h>
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12 #include <stdio.h>
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13 #include <stdlib.h>
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14 #define CHUNKSIZE 10
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15 #define N 100
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16
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17 int main (int argc, char *argv[]) {
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18
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19 int nthreads, tid, i, chunk;
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20 float a[N], b[N], c[N];
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21
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22 /* Some initializations */
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23 for (i=0; i < N; i++)
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24 a[i] = b[i] = i * 1.0;
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25 chunk = CHUNKSIZE;
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26
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27 #pragma omp parallel shared(a,b,c,nthreads,chunk) private(i,tid)
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28 {
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29 tid = omp_get_thread_num();
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30 if (tid == 0)
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31 {
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32 nthreads = omp_get_num_threads();
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33 printf("Number of threads = %d\n", nthreads);
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34 }
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35 printf("Thread %d starting...\n",tid);
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36
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37 #pragma omp for schedule(dynamic,chunk)
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38 for (i=0; i<N; i++)
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39 {
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40 c[i] = a[i] + b[i];
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41 printf("Thread %d: c[%d]= %f\n",tid,i,c[i]);
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42 }
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43
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44 } /* end of parallel section */
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45
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46 return 0;
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47 }
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