forked from ccf-ai-infra/GPUCodeForces
48 lines
1.3 KiB
Python
48 lines
1.3 KiB
Python
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import torch
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from torch.utils.cpp_extension import load_inline
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# Swish激活函数的CUDA实现 (x * sigmoid(x))
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swish_source = """
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#include <torch/extension.h>
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#include <cuda_runtime.h>
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__global__ void swish_kernel(const float* x, float* y, int size) {
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int idx = blockIdx.x * blockDim.x + threadIdx.x;
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if (idx < size) {
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// 高效计算Swish: x * (1 / (1 + exp(-x)))
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float val = x[idx];
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float sigmoid = 1.0f / (1.0f + expf(-val));
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y[idx] = val * sigmoid;
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}
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}
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torch::Tensor swish_cuda(torch::Tensor x) {
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auto size = x.numel();
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auto y = torch::empty_like(x);
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const int block_size = 256;
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int num_blocks = (size + block_size - 1) / block_size;
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swish_kernel<<<num_blocks, block_size>>>(x.data_ptr<float>(), y.data_ptr<float>(), size);
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return y;
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}
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"""
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swish_cpp_source = """
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torch::Tensor swish_cuda(torch::Tensor x);
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"""
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# 编译内联CUDA代码
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swish = load_inline(
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name="swish",
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cpp_sources=swish_cpp_source,
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cuda_sources=swish_source,
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functions=["swish_cuda"],
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verbose=True
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)
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class ModelNew(torch.nn.Module):
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def __init__(self):
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super(ModelNew, self).__init__()
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self.swish = swish # 包含自定义Swish算子的模块
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def forward(self, x):
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return self.swish.swish_cuda(x)
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