chundoong-lab-ta/SHPC2022/hw4_answer/riemannsum/main.c

89 lines
2.2 KiB
C

#include <getopt.h>
#include <math.h>
#include <mpi.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include "riemannsum.h"
#include "util.h"
static int num_intervals = 8;
static int threads_per_process = 8;
static int mpi_rank, mpi_world_size;
static void print_help(const char *prog_name) {
if (mpi_rank == 0) {
printf("Usage: %s [-h] [-t threads_per_process] N\n", prog_name);
printf("Options:\n");
printf(" -h : print this page.\n");
printf(" -t : number of threads per process (default: 8).\n");
printf(" N : number of intervals (default: 8)\n");
}
}
static void parse_opt(int argc, char **argv) {
int c;
while ((c = getopt(argc, argv, "pvht:n:")) != -1) {
switch (c) {
case 't':
threads_per_process = atoi(optarg);
break;
case 'h':
default:
print_help(argv[0]);
MPI_Finalize();
exit(0);
}
}
for (int i = optind, j = 0; i < argc; ++i, ++j) {
switch (j) {
case 0:
num_intervals = atoi(argv[i]);
break;
default:
break;
}
}
if (mpi_rank == 0) {
printf("Options:\n");
printf(" Number of intervals: %d\n", num_intervals);
printf(" Number of threads per process: %d\n", threads_per_process);
printf("\n");
}
}
int main(int argc, char **argv) {
MPI_Init(&argc, &argv);
MPI_Comm_rank(MPI_COMM_WORLD, &mpi_rank);
MPI_Comm_size(MPI_COMM_WORLD, &mpi_world_size);
char processor_name[MPI_MAX_PROCESSOR_NAME];
int name_len;
MPI_Get_processor_name(processor_name, &name_len);
printf("(%s) Hello world, rank %d out of %d\n", processor_name, mpi_rank,
mpi_world_size);
MPI_Barrier(MPI_COMM_WORLD);
parse_opt(argc, argv);
MPI_Barrier(MPI_COMM_WORLD);
double pi_estimate =
riemannsum(num_intervals, mpi_rank, mpi_world_size, threads_per_process);
MPI_Barrier(MPI_COMM_WORLD);
if (mpi_rank == 0) {
printf("[rank %d] Estimated PI value: %.10f\n", mpi_rank, pi_estimate);
printf("[rank %d] Relative error: %.4e\n", mpi_rank,
(pi_estimate - M_PI) / M_PI);
printf("[rank %d] Validation: ", mpi_rank);
check_riemannsum(num_intervals, pi_estimate);
}
MPI_Finalize();
return 0;
}