Files
CS3841/03-MatrixAddition (fork)/matAddFork.c
2023-02-21 18:22:20 -06:00

121 lines
3.0 KiB
C

#include <stdio.h>
#include <stdlib.h>
#include <inttypes.h>
#include <time.h>
#include <fcntl.h>
#include <sys/mman.h>
#include <sys/shm.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <unistd.h>
#define NS_PER_SEC 1000000000
#define MAX 10
static inline uint64_t gettime_ns() {
struct timespec ts;
clock_gettime(CLOCK_REALTIME, &ts);
return ts.tv_sec * NS_PER_SEC + ts.tv_nsec;
}
int main(int argc, char* argv[]) {
// Debug args
//argv[1] = "matrices/matC";
//argv[2] = "matrices/matD";
uint64_t start, end;
int rows, cols;
// Matrix 1
FILE* input1 = fopen(argv[1], "r");
fscanf(input1, "%d", &rows);
fscanf(input1, "%d", &cols);
int * matrix1 = (int *)malloc(rows*cols*sizeof(int));
for(int i = 0; i < rows*cols; i++) {
int value;
fscanf(input1, "%d", &value);
matrix1[i] = value;
}
fclose(input1);
// Matrix 2
FILE* input2 = fopen(argv[2], "r");
fscanf(input2, "%d", &rows);
fscanf(input2, "%d", &cols);
int * matrix2 = (int *)malloc(rows*cols*sizeof(int));
for(int i = 0; i < rows*cols; i++) {
int value;
fscanf(input2, "%d", &value);
matrix2[i] = value;
}
fclose(input2);
// Create shared memory object for result
int shm_fd = shm_open("MATRIX", O_CREAT | O_RDWR, 0666);
if (shm_fd == -1) {
perror("Error creating shared memory object");
exit(1);
}
// Resize shared memory object to fit result
if (ftruncate(shm_fd, rows*cols*sizeof(int))) {
perror("Error resizing shared memory object");
exit(1);
}
// Map shared memory object to C
int *result = mmap(NULL, rows*cols*sizeof(int), PROT_READ | PROT_WRITE, MAP_SHARED, shm_fd, 0);
if (result == MAP_FAILED) {
perror("Error mapping shared memory object to C");
exit(1);
}
// Allocate Memory for pids
int* pids = (int*)malloc(rows*sizeof(pid_t));
// Perform Forked Process Matrix Addition
start = gettime_ns();
for (int i = 0; i < rows; i++) {
pids[i] = fork();
if(pids[i] == -1) {
// Fork error
perror("Error with creating process\n");
return 1;
}
if(pids[i] == 0) {
// Child process
for(int j = 0; j < cols; j++) {
result[i*cols+j] = matrix1[i*cols+j] + matrix2[i*cols+j];
}
//printf("%d",pids[i]);
return 1;
}
}
end = gettime_ns();
for (int i = 0; i < rows; i++) {
waitpid(pids[i], NULL, 0);
}
end = gettime_ns();
// Print result to console
for (int i = 0; i < rows * cols; i++) {
printf("%2d ", result[i]);
if ((i + 1) % cols == 0) {
printf("\n");
}
}
printf("Addition took %" PRIu64 " nanoseconds\n", end - start);
free(matrix1);
free(matrix2);
// Unmap and unlink shared memory object
munmap(result, rows*cols*sizeof(int));
close(shm_fd);
shm_unlink("MATRIX");
}