import torch
import torch.nn as nn
import torch.nn.functional as F
import math
def module_fn(x: torch.Tensor) -> torch.Tensor:
"""
Implementation of the Gaussian Error Linear Units (GELU) activation function currently in Google BERT repo (identical to OpenAI GPT).
Args:
x (torch.Tensor): Input tensor.
Returns:
torch.Tensor: Output tensor.
"""
return (
0.5
* x
* (
1.0
+ torch.tanh(math.sqrt(2.0 / math.pi) * (x + 0.044715 * torch.pow(x, 3.0)))
)
)
class Model(nn.Module):
"""
Implementation of the GELU activation function currently in Google BERT repo (identical to OpenAI GPT).
Reference: Gaussian Error Linear Units (GELU) paper: https://arxiv.org/abs/1606.08415
"""
def __init__(self):
super(Model, self).__init__()
def forward(self, x, fn=module_fn):
return fn(x)
batch_size = 2000
dim = 2000
def get_inputs():
return [torch.randn(batch_size, dim)]
def get_init_inputs():
return []
import torch
import torch.nn as nn
import torch.nn.functional as F
import math
# From https://github.com/karpathy/minGPT/blob/master/mingpt/model.py
class Model(nn.Module):
"""
Implementation of the GELU activation function currently in Google BERT repo (identical to OpenAI GPT).
Reference: Gaussian Error Linear Units (GELU) paper: https://arxiv.org/abs/1606.08415
"""
def __init__(self):
super(Model, self).__init__()
def forward(self, x):
return (
0.5
* x
* (
1.0
+ torch.tanh(
math.sqrt(2.0 / math.pi) * (x + 0.044715 * torch.pow(x, 3.0))
)
)
)
batch_size = 2000
dim = 2000
def get_inputs():
return [torch.randn(batch_size, dim)]
def get_init_inputs():
return []
#include <torch/extension.h>
#include <cuda.h>
#include <cuda_runtime.h>
#include <math.h>
__global__ void gelu_kernel_shared(const float* __restrict__ x, float* __restrict__ y, int n) {
const float sqrt_2_over_pi = 0.7978845608f;
const float coeff = 0.044715f;
extern __shared__ float shared_x[];
const int tid = threadIdx.x;
const int gid = blockIdx.x * blockDim.x * 4 + tid;
// Load data into shared memory
#pragma unroll
for (int i = 0; i < 4; i++) {
const int idx = gid + i * blockDim.x;
if (idx < n) {
shared_x[tid + i * blockDim.x] = x[idx];
}
}
__syncthreads();
// Process elements using shared memory
#pragma unroll
for (int i = 0; i < 4; i++) {
const int idx = gid + i * blockDim.x;
if (idx < n) {
float xi = shared_x[tid + i * blockDim.x];
float x_cubed = xi * xi * xi;
float inner = xi + coeff * x_cubed;
inner *= sqrt_2_over_pi;
float tanh_val = tanhf(inner);
y[idx] = 0.5f * xi * (1.0f + tanh_val);
}
}
}
torch::Tensor gelu_forward(torch::Tensor x) {
TORCH_CHECK(x.is_cuda(), "Input tensor must be on CUDA");
TORCH_CHECK(x.is_contiguous(), "Input tensor must be contiguous");
auto y = torch::empty_like(x);
int n = x.numel();
const int threads = 256;
int blocks = (n + threads * 4 - 1) / (threads * 4);
// Allocate shared memory for the block
size_t shared_mem_size = threads * 4 * sizeof(float);
gelu_kernel_shared<<<blocks, threads, shared_mem_size>>>(
x.data_ptr<float>(),
y.data_ptr<float>(),
n
);
return y;
}
PYBIND11_MODULE(TORCH_EXTENSION_NAME, m) {
m.def("forward", &gelu_forward, "GELU forward CUDA implementation with shared memory");
}
Metric | Value | Unit | Variance | Samples |
---|---|---|---|---|
Executed Ipc Active | 2.852 | inst/cycle | 0.000 | 5 |
Executed Ipc Elapsed | 2.264 | inst/cycle | 0.001 | 5 |
Issue Slots Busy | 71.460 | % | 0.025 | 5 |
Issued Ipc Active | 2.860 | inst/cycle | 0.000 | 5 |
SM Busy | 71.460 | % | 0.025 | 5 |
Memory Throughput | 1360166362187.542 | byte/second | 124489954523502608384.000 | 5 |
Mem Busy | 33.646 | % | 0.084 | 5 |
Max Bandwidth | 40.706 | % | 0.106 | 5 |
L1/TEX Hit Rate | 0.000 | % | 0.000 | 5 |
L2 Hit Rate | 50.362 | % | 0.015 | 5 |
Mem Pipes Busy | 32.346 | % | 0.114 | 5 |
Warp Cycles Per Issued Instruction | 19.090 | cycle | 0.008 | 5 |
Warp Cycles Per Executed Instruction | 19.132 | cycle | 0.008 | 5 |
Avg. Active Threads Per Warp | 25.350 | 0.000 | 5 | |
Avg. Not Predicated Off Threads Per Warp | 24.340 | 0.000 | 5 | |
Max Active Clusters | 0.000 | cluster | 0.000 | 5 |
Max Cluster Size | 8.000 | block | 0.000 | 5 |
Overall GPU Occupancy | 0.000 | % | 0.000 | 5 |
Cluster Occupancy | 0.000 | % | 0.000 | 5 |
Block Limit SM | 32.000 | block | 0.000 | 5 |
Block Limit Registers | 10.000 | block | 0.000 | 5 |
Block Limit Shared Mem | 20.000 | block | 0.000 | 5 |
Block Limit Warps | 8.000 | block | 0.000 | 5 |
Theoretical Active Warps per SM | 64.000 | warp | 0.000 | 5 |
Theoretical Occupancy | 100.000 | % | 0.000 | 5 |
Achieved Occupancy | 85.626 | % | 0.006 | 5 |
Achieved Active Warps Per SM | 54.800 | warp | 0.003 | 5 |
Rule | Description |
---|---|
INF HighPipeUtilization | FMA is the highest-utilized pipeline (31.6%) based on active cycles, taking into account the rates of its different instructions. It executes 32-bit floating point (FADD, FMUL, FMAD, ...) and integer (IMUL, IMAD) operations. It is well-utilized, but should not be a bottleneck. |
WRN Occupancy | This kernel's theoretical occupancy is not impacted by any block limit. The difference between calculated theoretical (100.0%) and measured achieved occupancy (85.6%) can be the result of warp scheduling overheads or workload imbalances during the kernel execution. Load imbalances can occur between warps within a block as well as across blocks of the same kernel. See the CUDA Best Practices Guide (https://docs.nvidia.com/cuda/cuda-c-best-practices-guide/index.html#occupancy) for more details on optimizing occupancy. |
Operation / Metric | Value | Unit |
---|---|---|
aten::to | ||
CPU Time | 596227.59 | μs |
Device Time | 1562.02 | μs |
Self CPU Time | 41.82 | μs |
Self Device Time | 0.00 | μs |
CPU Memory Usage | 0 | B |
Device Memory Usage | 0 | B |
Self CPU Memory Usage | 0 | B |
Self Device Memory Usage | 0 | B |
aten::_to_copy | ||
CPU Time | 596185.77 | μs |
Device Time | 1562.02 | μs |
Self CPU Time | 105.73 | μs |
Self Device Time | 0.00 | μs |
CPU Memory Usage | 0 | B |
Device Memory Usage | 0 | B |
Self CPU Memory Usage | 0 | B |
Self Device Memory Usage | 0 | B |
aten::empty_strided | ||
CPU Time | 612907.76 | μs |
Device Time | 0.00 | μs |
Self CPU Time | 16876.48 | μs |
Self Device Time | 0.00 | μs |
CPU Memory Usage | 0 | B |
Device Memory Usage | 0 | B |
Self CPU Memory Usage | 0 | B |
Self Device Memory Usage | 0 | B |
cudaDeviceGetStreamPriorityRange | ||
CPU Time | 590394.31 | μs |
Device Time | 0.00 | μs |
Self CPU Time | 590394.31 | μs |
Self Device Time | 0.00 | μs |
CPU Memory Usage | 0 | B |
Device Memory Usage | 0 | B |
Self CPU Memory Usage | 0 | B |
Self Device Memory Usage | 0 | B |
cudaLaunchKernel | ||
CPU Time | 538657.61 | μs |
Device Time | 20807.95 | μs |
Self CPU Time | 538657.61 | μs |
Self Device Time | 20807.95 | μs |
CPU Memory Usage | 0 | B |
Device Memory Usage | 0 | B |
Self CPU Memory Usage | 0 | B |
Self Device Memory Usage | 0 | B |
gelu_kernel_shared(float const*, float*, int) | ||
CPU Time | 0.00 | μs |
Device Time | 104542.62 | μs |
Self CPU Time | 0.00 | μs |
Self Device Time | 104542.62 | μs |
CPU Memory Usage | 0 | B |
Device Memory Usage | 0 | B |
Self CPU Memory Usage | 0 | B |
Self Device Memory Usage | 0 | B |
cudaEventRecord | ||
CPU Time | 18399.08 | μs |
Device Time | 40191.97 | μs |
Self CPU Time | 18399.08 | μs |
Self Device Time | 40191.97 | μs |
CPU Memory Usage | 0 | B |
Device Memory Usage | 0 | B |
Self CPU Memory Usage | 0 | B |
Self Device Memory Usage | 0 | B |
aten::zero_ | ||
CPU Time | 83305.24 | μs |
Device Time | 596310.49 | μs |
Self CPU Time | 13034.94 | μs |
Self Device Time | 0.00 | μs |
CPU Memory Usage | 0 | B |
Device Memory Usage | 0 | B |
Self CPU Memory Usage | 0 | B |
Self Device Memory Usage | 0 | B |
aten::fill_ | ||
CPU Time | 70271.55 | μs |
Device Time | 596310.49 | μs |
Self CPU Time | 15149.01 | μs |
Self Device Time | 596310.49 | μs |
CPU Memory Usage | 0 | B |
Device Memory Usage | 0 | B |
Self CPU Memory Usage | 0 | B |
Self Device Memory Usage | 0 | B |
void at::native::vectorized_elementwise_kernel<4, at::native::FillFunctor<int>, at::detail::Array<char*, 1> >(int, at::native::FillFunctor<int>, at::detail::Array<char*, 1>) | ||
CPU Time | 0.00 | μs |
Device Time | 596310.49 | μs |
Self CPU Time | 0.00 | μs |
Self Device Time | 596310.49 | μs |
CPU Memory Usage | 0 | B |
Device Memory Usage | 0 | B |
Self CPU Memory Usage | 0 | B |
Self Device Memory Usage | 0 | B |
45281 warnings generated when compiling for host. Suppressed 45321 warnings (45274 in non-user code, 47 NOLINT). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well.