chundoong-lab-ta/SamsungDS22/submissions/HW6/seong81.kim/mat_mul.cu

214 lines
7.0 KiB
Plaintext
Raw Normal View History

2022-09-29 18:01:45 +09:00
#include "mat_mul.h"
#include <cstdio>
#include <cuda_runtime.h>
#define TS 32
#define WPT 16
#define RTS (TS / WPT)
#define CUDA_CALL(f) \
{ \
cudaError_t err = (f); \
if (err != cudaSuccess) { \
fprintf(stderr, "CUDA error at [%s:%d] %d %s\n", __FILE__, __LINE__, \
err, cudaGetErrorString(err)); \
exit(1); \
} \
}
#define MAX_NUM_GPU 4
int num_devices = 0;
__global__ void sgemm(float *A, float *B, float *C, int M, int N, int K) {
// Thread identifiers
const int row = threadIdx.x; // Local row ID (max: TS)
const int col = threadIdx.y; // Local col ID (max: TS/WPT == RTS)
const int globalRow = (blockDim.x * WPT) * blockIdx.x + row; // Row ID of C (0..M)
const int globalCol = blockDim.y * blockIdx.y + col; // Col ID of C (0..N)
// Local memory to fit a tile of TS*TS elements of A and B
__shared__ float Asub[TS][TS];
__shared__ float Bsub[TS][TS];
// Initialise the accumulation registers
float tempVal[WPT];
for (int w=0; w<WPT; w++)
tempVal[w] = 0.0f;
// Loop over all tiles
const int numTiles = (K + TS - 1) / TS ; // Ceiling to Tile Size
//const int numTiles = (K / TS) + 1 - (K % TS == 0);
for (int t=0; t<numTiles; t++) {
// Load one tile of A and B into local memory
for (int w=0; w<WPT; w++) {
const int tiledRow = TS*t + row;
const int tiledCol = TS*t + col;
const int orgM = globalRow + w*RTS ;
const int orgK = tiledRow + w*RTS ;
// Copy Global A to local
if ( (orgM < M) && (tiledCol < K) )
Asub[row + w*RTS][col] = A[orgM*K + tiledCol] ;
else
Asub[row + w*RTS][col] = 0.0f ;
// Copy Global B to local
if ( (orgK < K) && (globalCol < N) )
Bsub[row + w*RTS][col] = B[orgK*N + globalCol] ;
else
Bsub[row + w*RTS][col] = 0.0f ;
}
// Synchronise to make sure the tile is loaded
//barrier(CLK_LOCAL_MEM_FENCE);
__syncthreads() ;
// Perform the computation for a single tile
for (int k=0; k<TS; k++) {
for (int w=0; w<WPT; w++) {
tempVal[w] += Asub[row + w*RTS][k] * Bsub[k][col];
}
}
// Synchronise before loading the next tile
//barrier(CLK_LOCAL_MEM_FENCE);
__syncthreads() ;
}
// Store the final results in C
for (int w=0; w<WPT; w++) {
const int orgM = globalRow + w*RTS ;
if ( (orgM < M) && (globalCol < N) )
C[orgM * N + globalCol] = tempVal[w];
}
//int i = blockDim.x * blockIdx.x + threadIdx.x;
//int j = blockDim.y * blockIdx.y + threadIdx.y;
//if (i >= M || j >= N)
// return;
//
//C[i * N + j] = 0;
//for (int k = 0; k < K; ++k) {
// C[i * N + j] += A[i * K + k] * B[k * N + j];
//}
}
// Array of device (GPU) pointers
static float *a_d[MAX_NUM_GPU];
static float *b_d[MAX_NUM_GPU];
static float *c_d[MAX_NUM_GPU];
static int M, N, K;
static int M_str[MAX_NUM_GPU], M_siz[MAX_NUM_GPU];
//static int Mbegin[MAX_NUM_GPU], Mend[MAX_NUM_GPU];
void mat_mul(float *_A, float *_B, float *_C, int _M, int _N, int _K) {
// Launch kernel on every GPU
for (int i = 0; i < num_devices; i++) {
dim3 blockDim(TS/WPT, TS, 1);
dim3 gridDim( (M_siz[i] + TS - 1) / TS, (N + TS - 1) / TS, 1);
//dim3 gridDim( (Mend[i] - Mbegin[i] +TS - 1) / TS, (N + TS - 1) / TS, 1);
CUDA_CALL( cudaSetDevice(i) );
sgemm<<<gridDim, blockDim>>>(a_d[i], b_d[i], c_d[i], M_siz[i], N, K);
}
// DO NOT REMOVE; NEEDED FOR TIME MEASURE
for (int i = 0; i < num_devices; i++) {
CUDA_CALL( cudaDeviceSynchronize() );
}
}
void mat_mul_init(float *A, float *B, float *C, int _M, int _N, int _K) {
M = _M, N = _N, K = _K;
CUDA_CALL( cudaGetDeviceCount(&num_devices) );
printf("Using %d devices\n", num_devices);
for (int i = 0; i < num_devices; i++) {
cudaDeviceProp prop;
CUDA_CALL( cudaGetDeviceProperties(&prop, i) );
// Try printing more detailed information here
printf("[GPU %d] %s\n", i, prop.name);
}
if (num_devices <= 0) {
printf("No CUDA device found. Aborting\n");
exit(1);
}
// Setup problem size for each GPU
M_str [0] = 0 ;
M_siz [0] = M / num_devices ;
int mod = M % num_devices ;
if (mod != 0)
M_siz[0] = M_siz[0] + mod ;
// Assign Remained Device
for (int i = 1 ; i < num_devices ; i++){
M_str[i] = M_str[i - 1] + M_siz[i - 1];
if (i == num_devices - 1) { // Last Device
M_siz[i] = M - M_str[i] ;
} else {
M_siz[i] = M / num_devices ;
}
}
//for (int i = 0; i < num_devices; i++) {
// Mbegin[i] = (M / num_devices) * i;
// Mend[i] = (M / num_devices) * (i + 1);
//}
//Mend[num_devices - 1] = M;
// Allocate device memory for each GPU
for (int i = 0; i < num_devices; i++) {
CUDA_CALL( cudaSetDevice(i) );
CUDA_CALL( cudaMalloc(&a_d[i], M_siz[i] * K * sizeof(float)) );
CUDA_CALL( cudaMalloc(&b_d[i], K * N * sizeof(float)) );
CUDA_CALL( cudaMalloc(&c_d[i], M_siz[i] * N * sizeof(float)) );
//CUDA_CALL( cudaMalloc(&a_d[i], (Mend[i] - Mbegin[i]) * K * sizeof(float)) );
//CUDA_CALL( cudaMalloc(&b_d[i], K * N * sizeof(float)) );
//CUDA_CALL( cudaMalloc(&c_d[i], (Mend[i] - Mbegin[i]) * N * sizeof(float)) );
}
// Upload A and B matrix to every GPU
for (int i = 0; i < num_devices; i++) {
CUDA_CALL( cudaMemcpy(a_d[i], &A[M_str[i] * K], M_siz[i] * K * sizeof(float), cudaMemcpyHostToDevice) );
CUDA_CALL( cudaMemcpy(b_d[i], B , K * N * sizeof(float), cudaMemcpyHostToDevice) );
//CUDA_CALL( cudaMemcpy(a_d[i], A + Mbegin[i] * K,
// (Mend[i] - Mbegin[i]) * K * sizeof(float),
// cudaMemcpyHostToDevice) );
//CUDA_CALL( cudaMemcpy(b_d[i], B, K * N * sizeof(float), cudaMemcpyHostToDevice) );
}
// DO NOT REMOVE; NEEDED FOR TIME MEASURE
for (int i = 0; i < num_devices; i++) {
CUDA_CALL( cudaDeviceSynchronize() );
}
}
void mat_mul_final(float *A, float *B, float *C, int M, int N, int K) {
// Do any post-matmul cleanup work here.
// Download C matrix from GPUs
for (int i = 0; i < num_devices; i++) {
CUDA_CALL( cudaMemcpy(&C[M_str[i] * N], c_d[i], M_siz[i] * N * sizeof(float), cudaMemcpyDeviceToHost) );
//CUDA_CALL( cudaMemcpy(C + Mbegin[i] * N, c_d[i],
// (Mend[i] - Mbegin[i]) * N * sizeof(float),
// cudaMemcpyDeviceToHost) );
}
// DO NOT REMOVE; NEEDED FOR TIME MEASURE
for (int i = 0; i < num_devices; i++) {
CUDA_CALL( cudaDeviceSynchronize() );
}
}