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#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#include <sys/types.h>
#include <sys/times.h>
#include <sys/time.h>
#include <omp.h>
struct timeval2 {
long tv_sec; /* second */
long tv_usec; /* microsecond */
};
void dtime(double *t);
double func1(int kp, int N);
int main(int argc, char *argv[])
{
int i,id,Nthrds,Nprocs,N,k,kp;
double sum[100],tsum;
double stime,etime;
dtime(&stime);
N = 30000000;
k = 0;
#pragma omp parallel shared(k,sum) private(i,id,kp,tsum)
{
id = omp_get_thread_num();
Nthrds = omp_get_num_threads();
Nprocs = omp_get_num_procs();
printf("Nprocs=%2d Nthrds=%2d id=%d\n",Nprocs,Nthrds,id);
kp = id;
k = Nthrds-1;
do {
sum[kp] = func1(kp, N);
printf("id=%2d kp=%2d sum=%15.12f\n",id,kp,sum[kp]);
#pragma omp critical
kp = ++k;
}
while (k<20);
#pragma omp barrier
{
tsum = 0.0;
for (i=0; i<20; i++){
tsum += sum[i];
}
}
printf("tsum=%15.12f\n",tsum);
}
dtime(&etime);
printf("Elapsed time (s)=%15.12f\n",etime-stime);
return 0;
}
double func1(int kp, int N)
{
int i;
double tmp;
tmp = 0.0;
for (i=0; i<N; i++){
tmp += sin((double)(i+kp))+cos((double)(i+2*kp));
}
return tmp;
}
void dtime(double *t)
{
/* real time */
struct timeval timev;
gettimeofday(&timev, NULL);
*t = timev.tv_sec + (double)timev.tv_usec*1e-6;
/* user time + system time */
/*
float tarray[2];
clock_t times(), wall;
struct tms tbuf;
wall = times(&tbuf);
tarray[0] = (float) (tbuf.tms_utime / (float)CLK_TCK);
tarray[1] = (float) (tbuf.tms_stime / (float)CLK_TCK);
*t = (double) (tarray[0]+tarray[1]);
printf("dtime: %lf\n",*t);
*/
}
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