GPUCodeForces/S1/uucoco_#7/MinkowskiDistance_cuda.py

148 lines
4.2 KiB
Python

import torch
import torch.nn as nn
from torch.utils.cpp_extension import load_inline
N, C, H, W = 32, 64, 56, 56
EPS = 1e-6
assert (C * H * W) % 4 == 0, "Instance size (C*H*W) must be a multiple of 4"
class ModelNew(nn.Module):
def __init__(self, p=3.0):
super().__init__()
self.p = float(p)
self.eps = EPS
self.blocks_per_instance = 16
self._compile_cuda_kernel()
def _compile_cuda_kernel(self):
cpp_source = """
#include <torch/extension.h>
void minkowski_sum_cuda(
torch::Tensor x,
torch::Tensor y,
torch::Tensor out,
float p,
int N,
int D,
int blocks_per_instance);
"""
cuda_source = """
#include <cuda_runtime.h>
#include <cmath>
#define WARP_SIZE 32
__inline__ __device__ float warp_reduce_sum(float val) {
for (int offset = WARP_SIZE / 2; offset > 0; offset /= 2) {
val += __shfl_down_sync(0xffffffff, val, offset);
}
return val;
}
__inline__ __device__ float block_reduce_sum(float val) {
__shared__ float shared[32];
int lane = threadIdx.x % WARP_SIZE;
int wid = threadIdx.x / WARP_SIZE;
val = warp_reduce_sum(val);
if (lane == 0) shared[wid] = val;
__syncthreads();
val = (threadIdx.x < blockDim.x / WARP_SIZE) ? shared[lane] : 0.0f;
if (wid == 0) val = warp_reduce_sum(val);
return val;
}
__global__ void minkowski_sum_kernel(
const float* __restrict__ x,
const float* __restrict__ y,
float* __restrict__ out,
float p,
int N,
int D_vec
) {
int n_idx = blockIdx.x;
int stride = blockDim.x * gridDim.y;
int d_start = blockIdx.y * blockDim.x + threadIdx.x;
int offset_base = n_idx * D_vec * 4;
const float4* x4_ptr = reinterpret_cast<const float4*>(x + offset_base);
const float4* y4_ptr = reinterpret_cast<const float4*>(y + offset_base);
float local_sum = 0.0f;
for (int i = d_start; i < D_vec; i += stride) {
float4 vx = x4_ptr[i];
float4 vy = y4_ptr[i];
local_sum += powf(fabsf(vx.x - vy.x), p);
local_sum += powf(fabsf(vx.y - vy.y), p);
local_sum += powf(fabsf(vx.z - vy.z), p);
local_sum += powf(fabsf(vx.w - vy.w), p);
}
float block_sum = block_reduce_sum(local_sum);
if (threadIdx.x == 0) {
atomicAdd(&out[n_idx], block_sum);
}
}
void minkowski_sum_cuda(
torch::Tensor x,
torch::Tensor y,
torch::Tensor out,
float p,
int N,
int D,
int blocks_per_instance)
{
dim3 blocks(N, blocks_per_instance);
dim3 threads(256);
int D_vec = D / 4;
minkowski_sum_kernel<<<blocks, threads>>>(
x.data_ptr<float>(),
y.data_ptr<float>(),
out.data_ptr<float>(),
p,
N,
D_vec
);
}
"""
self.op = load_inline(
name='minkowski_cuda_opt_v2',
cpp_sources=cpp_source,
cuda_sources=cuda_source,
functions=['minkowski_sum_cuda'],
extra_cuda_cflags=['-O3', '--use_fast_math'],
verbose=False
)
def forward(self, x: torch.Tensor, y: torch.Tensor) -> torch.Tensor:
if not x.is_cuda: x = x.cuda()
if not y.is_cuda: y = y.cuda()
x = x.contiguous()
y = y.contiguous()
N, C, H, W = x.size()
D = C * H * W
out = torch.zeros(N, device=x.device, dtype=x.dtype)
self.op.minkowski_sum_cuda(
x,
y,
out,
self.p,
N,
D,
self.blocks_per_instance
)
return torch.pow(out + self.eps, 1.0 / self.p)