chundoong-lab-ta/SamsungDS22/submissions/HW2/ys798.choi/mat_mul.cpp

73 lines
1.4 KiB
C++

#include "mat_mul.h"
#include <cstdlib>
#include <cstdio>
#include <pthread.h>
#include <algorithm>
#define BLOCK_SIZE 32
static float *A, *B, *C;
static int M, N, K;
static int num_threads;
static void* mat_mul_thread(void *data) {
// TODO: parallelize & optimize matrix multiplication
int i,j,k;
int kk;
int Bsize = BLOCK_SIZE;
int id = *(int*)data;
int slice = M / num_threads;
int start_ptr = slice * id;
int end_ptr = (id == (num_threads-1)) ? M : (id+1) * slice;
float A_mac;
for (kk = 0; kk < K; kk += Bsize)
{
for (i = start_ptr; i < end_ptr; ++i)
{
for (k = kk; k < std::min(kk + Bsize, K); ++k)
{
A_mac = A[i*K+k];
for (j = 0; j < N; ++j)
{
C[i*N+j] += A_mac * B[k*N+j];
}
}
}
}
return NULL;
}
void mat_mul(float *_A, float *_B, float *_C, int _M, int _N, int _K, int _num_threads) {
A = _A, B = _B, C = _C;
M = _M, N = _N, K = _K;
num_threads = _num_threads;
// TODO: create '_num_threads' pthreads
int i;
pthread_t *pthreads;
pthreads = (pthread_t*) malloc(sizeof(pthread_t) * num_threads);
for (i=0; i<num_threads; i++)
{
int * thread_id = (int *) malloc(sizeof(int));
// tID = i;
// thread_id = &tID;
*thread_id = i; //init
pthread_create(&pthreads[i], NULL, mat_mul_thread, thread_id);
}
for (i = 0; i < num_threads; i++)
{
pthread_join(pthreads[i], NULL);
}
free(pthreads);
}