chundoong-lab-ta/SamsungDS22/submissions/HW2/hongpooh.kim/mat_mul.cpp

140 lines
3.6 KiB
C++

#include "mat_mul.h"
#include <cstdlib>
#include <cstdio>
#include <pthread.h>
//#define BLOCKSIZE 128 // 200.00 GFLOPS
//#define BLOCKSIZE 64 // 287.41 GFLOPS
#define BLOCKSIZE 32 // 293.77 GFLOPS (290 ~ 295)
//#define BLOCKSIZE 16 // 199.14 GFLOPS
//#define BLOCKSIZE 4 // 69.86 GFLOPS
#define MIN(blk, total) (blk < total ? blk : total)
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, kk;
int pid;
int div;
int div_start, div_end;
pid = *(int *)data;
div = M / num_threads;
div_start = pid * div;
div_end = (pid == num_threads -1) ? M : (pid + 1) * div;
/* 1) original code
for (int i = 0; i < M; ++i) {
for (int j = 0; j < N; ++j) {
for (int k = 0; k < K; ++k) {
C[i * N + j] += A[i * K + k] * B[k * N + j];
}
}
}
*/
/* 2) pthread only
* ./run.sh -v -n 5 -t 1 1024 1024 1024 => 0.678401 GFLOPS
* ./run.sh -v -n 5 -t 2 1024 1024 1024 => 1.356989 GFLOPS
* ./run.sh -v -n 5 -t 3 1024 1024 1024 => 2.008897 GFLOPS
* ./run.sh -v -n 5 -t 4 1024 1024 1024 => 2.702098 GFLOPS
* ./run_performance.sh => Force Terminated (time over: 1 min)
for (int i = div_start; i < div_end; ++i) {
//for (int j = Ndiv_start; j < Ndiv_end ; ++j) {
for (int j = 0; j < N ; ++j) {
int k = 0;
for ( ; k < K; ++k) {
C[i * N + j] += A[i * K + k] * B[k * N + j];
}
}
}
*/
/* 3) prhead + block (final)
* ./run_performance.sh
* #define BLOCKSIZE 128 => 200.00 GFLOPS
* #define BLOCKSIZE 64 => 287.41 GFLOPS
* #define BLOCKSIZE 32 => 293.77 GFLOPS (290 ~ 295), 0.479 sec
* #define BLOCKSIZE 16 => 199.14 GFLOPS
* #define BLOCKSIZE 4 => 69.86 GFLOPS
*
* ./run.sh -v -n 10 -t 40 4096 4096 4096 => 0.411518 sec, 333.980281 GFLOPS
*/
for (kk =0; kk < K; kk += BLOCKSIZE) {
for (i = div_start; i < div_end; i++) {
for(k = kk; k < MIN(kk + BLOCKSIZE, K); k++) {
for (j = 0; j < N; j++) {
C[i * N + j] += A[i * K + k] * B[k * N + j];
}
}
}
}
/* test code - #1
* ./run.sh -v -n 5 -t 40 4096 4096 4096 => 4.808995 sec, 28.579559 GFLOPS
* ./run.sh -v -n 5 -t 20 4096 4096 4096 => time out
for (kk =0; kk < K; kk += BLOCKSIZE) {
for (i = div_start; i < div_end; i++) {
for (j = 0; j < N; j++) {
for(k = kk; k < MIN(kk + BLOCKSIZE, K); k++) {
C[i * N + j] += A[i * K + k] * B[k * N + j];
}
}
}
}
*/
/* test code - #2
* ./run_performance.sh => 4.621823 sec, 29.736956 GFLOPS
for (kk =0; kk < K; kk += BLOCKSIZE) {
for (i = div_start; i < div_end; i++) {
for(k = kk; k < MIN(kk + BLOCKSIZE, K); k++) {
float tmpC = 0;
for (j = 0; j < N; j++) {
//C[i * N + j] += A[i * K + k] * B[k * N + j];
tmpC += A[i * K + k] * B[k * N + j];
}
C[i * N + j] = tmpC;
}
}
}
*/
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
/* single thread ref. code
pthread_t thread;
pthread_create(&thread, NULL, mat_mul_thread, NULL);
pthread_join(thread, NULL);
*/
pthread_t *threads;
threads = (pthread_t *) malloc(sizeof(pthread_t) * num_threads);
for (int i = 0; i < num_threads; i++) {
int *pid = (int *) malloc(sizeof(int));
*pid = i;
pthread_create(&threads[i], NULL, mat_mul_thread, pid);
}
for (int i = 0; i < num_threads; i++) {
pthread_join(threads[i], NULL);
}
}