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53_Gemm_Scaling_Hardtanh_GELUmodular_functions_base_edit_1

Level 2 • Task 53
import torch
import torch.nn as nn
import torch.nn.functional as F


def module_fn(
    x: torch.Tensor,
    scaling_factor: float,
    hardtanh_min: float,
    hardtanh_max: float,
    weight: torch.Tensor,
    bias: torch.Tensor,
) -> torch.Tensor:
    """
    Applies GEMM, scaling, hardtanh and GELU activation.

    Args:
        x (torch.Tensor): Input tensor of shape (batch_size, in_features)
        scaling_factor (float): Factor to scale the GEMM output
        hardtanh_min (float): Minimum value for hardtanh
        hardtanh_max (float): Maximum value for hardtanh
        weight (torch.Tensor): Weight matrix of shape (out_features, in_features)
        bias (torch.Tensor): Bias vector of shape (out_features)

    Returns:
        torch.Tensor: Output tensor after applying GEMM, scaling, hardtanh and GELU,
            with shape (batch_size, out_features)
    """
    x = F.linear(x, weight, bias)
    x = x * scaling_factor
    x = F.hardtanh(x, min_val=hardtanh_min, max_val=hardtanh_max)
    x = F.gelu(x)
    return x


class Model(nn.Module):
    """
    Model that performs a GEMM, scaling, hardtanh, and GELU activation.
    """

    def __init__(
        self, in_features, out_features, scaling_factor, hardtanh_min, hardtanh_max
    ):
        super(Model, self).__init__()
        gemm = nn.Linear(in_features, out_features)
        self.weight = nn.Parameter(gemm.weight)
        self.bias = nn.Parameter(gemm.bias)
        self.scaling_factor = scaling_factor
        self.hardtanh_min = hardtanh_min
        self.hardtanh_max = hardtanh_max

    def forward(self, x, fn=module_fn):
        return fn(
            x,
            self.scaling_factor,
            self.hardtanh_min,
            self.hardtanh_max,
            self.weight,
            self.bias,
        )


batch_size = 128
in_features = 1024
out_features = 512
scaling_factor = 0.5
hardtanh_min = -2
hardtanh_max = 2


def get_inputs():
    return [torch.randn(batch_size, in_features)]


def get_init_inputs():
    return [in_features, out_features, scaling_factor, hardtanh_min, hardtanh_max]
import torch
import torch.nn as nn

class Model(nn.Module):
    """
    Model that performs a GEMM, scaling, hardtanh, and GELU activation.
    """
    def __init__(self, in_features, out_features, scaling_factor, hardtanh_min, hardtanh_max):
        super(Model, self).__init__()
        self.gemm = nn.Linear(in_features, out_features)
        self.scaling_factor = scaling_factor
        self.hardtanh = nn.Hardtanh(min_val=hardtanh_min, max_val=hardtanh_max)
        self.gelu = nn.GELU()

    def forward(self, x):
        x = self.gemm(x)
        x = x * self.scaling_factor
        x = self.hardtanh(x)
        x = self.gelu(x)
        return x

batch_size = 128
in_features = 1024
out_features = 512
scaling_factor = 0.5
hardtanh_min = -2
hardtanh_max = 2

def get_inputs():
    return [torch.randn(batch_size, in_features)]

def get_init_inputs():
    return [in_features, out_features, scaling_factor, hardtanh_min, hardtanh_max]

Kernel Information

Related Kernels (Level 2, Task 53 • 53_Gemm_Scaling_Hardtanh_GELU)

#include <torch/extension.h>
#include <cuda.h>
#include <cuda_runtime.h>

constexpr int BLOCK_SIZE = 512;

template <typename scalar_t>
__device__ inline scalar_t scale_value(scalar_t val, scalar_t factor) {
    return val * factor;
}

template <typename scalar_t>
__device__ inline scalar_t hard_tanh(scalar_t val, scalar_t min_val, scalar_t max_val) {
    return fminf(fmaxf(val, min_val), max_val);
}

template <typename scalar_t>
__device__ inline scalar_t gelu_activation(scalar_t val) {
    constexpr scalar_t c = (scalar_t)0.044715;
    constexpr scalar_t sqrt_2_over_pi = (scalar_t)0.7978845608028654;
    scalar_t x_cube = val * val * val;
    scalar_t tanh_arg = sqrt_2_over_pi * (val + c * x_cube);
    scalar_t tanh_res = tanh(tanh_arg);
    return 0.5 * val * (1.0 + tanh_res);
}

template <typename scalar_t>
__global__ void optimized_fused_kernel(
    scalar_t* __restrict__ x,
    scalar_t scaling_factor,
    scalar_t hardtanh_min,
    scalar_t hardtanh_max,
    int64_t numel) {
    
    int idx = blockIdx.x * BLOCK_SIZE + threadIdx.x;
    int stride = gridDim.x * BLOCK_SIZE;
    
    #pragma unroll 2
    for (; idx < numel; idx += stride) {
        scalar_t val = x[idx];
        val = scale_value(val, scaling_factor);
        val = hard_tanh(val, hardtanh_min, hardtanh_max);
        x[idx] = gelu_activation(val);
    }
}

void fused_activation_cuda(
    torch::Tensor& x,
    double scaling_factor,
    double hardtanh_min,
    double hardtanh_max) {
    
    const auto numel = x.numel();
    const dim3 blocks((numel + BLOCK_SIZE - 1) / BLOCK_SIZE);
    
    AT_DISPATCH_FLOATING_TYPES(x.scalar_type(), "fused_activation_cuda", ([&] {
        optimized_fused_kernel<scalar_t><<<blocks, BLOCK_SIZE>>>(
            x.data_ptr<scalar_t>(),
            (scalar_t)scaling_factor,
            (scalar_t)hardtanh_min,
            (scalar_t)hardtanh_max,
            numel);
    }));
}

torch::Tensor module_fn_forward(
    torch::Tensor x,
    double scaling_factor,
    double hardtanh_min,
    double hardtanh_max,
    torch::Tensor weight,
    torch::Tensor bias) {

    x = x.contiguous().cuda();
    weight = weight.contiguous().cuda();
    bias = bias.contiguous().cuda();

    auto xw = torch::matmul(x, weight.t()) + bias;
    fused_activation_cuda(xw, scaling_factor, hardtanh_min, hardtanh_max);

    return xw;
}

PYBIND11_MODULE(TORCH_EXTENSION_NAME, m) {
    m.def("forward", &module_fn_forward, "Optimized module function forward (CUDA)");
}
Performance Metrics
Metric Value Unit Variance Samples
Executed Ipc Active 0.564 inst/cycle 0.000 5
Executed Ipc Elapsed 0.176 inst/cycle 0.000 5
Issue Slots Busy 14.718 % 0.127 5
Issued Ipc Active 0.586 inst/cycle 0.000 5
SM Busy 14.718 % 0.127 5
Memory Throughput 80220455514.488 byte/second 4011377984223753728.000 5
Mem Busy 11.108 % 0.106 5
Max Bandwidth 7.192 % 0.026 5
L1/TEX Hit Rate 50.000 % 0.000 5
L2 Hit Rate 82.792 % 0.216 5
Mem Pipes Busy 4.944 % 0.015 5
Warp Cycles Per Issued Instruction 24.120 cycle 0.095 5
Warp Cycles Per Executed Instruction 25.294 cycle 0.103 5
Avg. Active Threads Per Warp 30.290 0.000 5
Avg. Not Predicated Off Threads Per Warp 29.210 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 5.000 block 0.000 5
Block Limit Shared Mem 16.000 block 0.000 5
Block Limit Warps 4.000 block 0.000 5
Theoretical Active Warps per SM 64.000 warp 0.000 5
Theoretical Occupancy 100.000 % 0.000 5
Achieved Occupancy 22.596 % 0.077 5
Achieved Active Warps Per SM 14.458 warp 0.031 5
Analysis Rules
Rule Description
WRN HighPipeUtilization All compute pipelines are under-utilized. Either this kernel is very small or it doesn't issue enough warps per scheduler. Check the Launch Statistics and Scheduler Statistics sections for further details.
INF CPIStall Check the Warp Stall Sampling (All Cycles) table for the top stall locations in your source based on sampling data. The Kernel Profiling Guide (https://docs.nvidia.com/nsight-compute/ProfilingGuide/index.html#metrics-reference) provides more details on each stall reason.
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 (22.6%) 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 346703.14 μs
Device Time 162.69 μs
Self CPU Time 12619.79 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::matmul
CPU Time 337995.77 μs
Device Time 165724.13 μs
Self CPU Time 12610.22 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::mm
CPU Time 325385.56 μs
Device Time 165724.13 μs
Self CPU Time 191485.03 μs
Self Device Time 165724.13 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 532592.61 μs
Device Time 17039.96 μs
Self CPU Time 532592.61 μs
Self Device Time 17039.96 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 489304.76 μs
Device Time 895246.46 μs
Self CPU Time 22282.28 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 467026.79 μs
Device Time 895246.46 μs
Self CPU Time 24717.42 μs
Self Device Time 895246.46 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 895246.46 μs
Self CPU Time 0.00 μs
Self Device Time 895246.46 μs
CPU Memory Usage 0 B
Device Memory Usage 0 B
Self CPU Memory Usage 0 B
Self Device Memory Usage 0 B
Status: Completed
45285 warnings generated when compiling for host.
Suppressed 45326 warnings (45279 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.
/home/robert_sakana_ai/llm_cuda/experiments/20250212_optimize_b5_s4_e1_v2/level_2/task_53/b3_s2_modular_functions_base/edit_1/edit_1.cu:30:5 bugprone-easily-swappable-parameters
30 | scalar_t scaling_factor,
| ^~~~~~~~~~~~~~~~~~~~~~~~
31 | scalar_t hardtanh_min,
| ~~~~~~~~~~~~~~~~~~~~~
/home/robert_sakana_ai/llm_cuda/experiments/20250212_optimize_b5_s4_e1_v2/level_2/task_53/b3_s2_modular_functions_base/edit_1/edit_1.cu:30:14: note: the first parameter in the range is 'scaling_factor'
30 | scalar_t scaling_factor,
| ^~~~~~~~~~~~~~
/home/robert_sakana_ai/llm_cuda/experiments/20250212_optimize_b5_s4_e1_v2/level_2/task_53/b3_s2_modular_functions_base/edit_1/edit_1.cu:31:14: note: the last parameter in the range is 'hardtanh_min'
31 | scalar_t hardtanh_min,
| ^~~~~~~~~~~~
/home/robert_sakana_ai/llm_cuda/experiments/20250212_optimize_b5_s4_e1_v2/level_2/task_53/b3_s2_modular_functions_base/edit_1/edit_1.cu:35:15: warning: narrowing conversion from 'unsigned int' to signed type 'int' is implementation-defined [bugprone-narrowing-conversions]
35 | int idx = blockIdx.x * BLOCK_SIZE + threadIdx.x;
| ^
/home/robert_sakana_ai/llm_cuda/experiments/20250212_optimize_b5_s4_e1_v2/level_2/task_53/b3_s2_modular_functions_base/edit_1/edit_1.cu:36:18: warning: narrowing conversion from 'unsigned int' to signed type 'int' is implementation-defined [bugprone-narrowing-conversions]
36 | int stride = gridDim.x * BLOCK_SIZE;
| ^
/home/robert_sakana_ai/llm_cuda/experiments/20250212_optimize_b5_s4_e1_v2/level_2/task_53/b3_s2_modular_functions_base/edit_1/edit_1.cu:56:5: warning: inside a lambda, '__func__' expands to the name of the function call operator; consider capturing the name of the enclosing function explicitly [bugprone-lambda-function-name]
56 | AT_DISPATCH_FLOATING_TYPES(x.scalar_type(), "fused_activation_cuda", ([&] {
| ^
/home/robert_sakana_ai/miniconda3/envs/llm2cuda/lib/python3.11/site-packages/torch/include/ATen/Dispatch.h:237:34: note: expanded from macro 'AT_DISPATCH_FLOATING_TYPES'
237 | AT_DISPATCH_SWITCH(TYPE, NAME, AT_DISPATCH_CASE_FLOATING_TYPES(__VA_ARGS__))
| ^
/home/robert_sakana_ai/miniconda3/envs/llm2cuda/lib/python3.11/site-packages/torch/include/ATen/Dispatch.h:233:3: note: expanded from macro 'AT_DISPATCH_CASE_FLOATING_TYPES'
233 | AT_DISPATCH_CASE(at::ScalarType::Double, __VA_ARGS__) \
| ^
/home/robert_sakana_ai/miniconda3/envs/llm2cuda/lib/python3.11/site-packages/torch/include/ATen/Dispatch.h:74:3: note: expanded from macro 'AT_DISPATCH_CASE'
74 | AT_PRIVATE_CASE_TYPE_USING_HINT(enum_type, scalar_t, __VA_ARGS__)
| ^
note: (skipping 1 expansions in backtrace; use -fmacro-backtrace-limit=0 to see all)
/home/robert_sakana_ai/miniconda3/envs/llm2cuda/lib/python3.11/site-packages/torch/include/ATen/Dispatch.h:58:7: note: expanded from macro 'AT_PRIVATE_CHECK_SELECTIVE_BUILD'
58 | AT_ERROR( \
| ^
/home/robert_sakana_ai/miniconda3/envs/llm2cuda/lib/python3.11/site-packages/torch/include/c10/util/Exception.h:711:32: note: expanded from macro 'AT_ERROR'
711 | C10_EXPAND_MSVC_WORKAROUND(TORCH_CHECK(false, ::c10::str(__VA_ARGS__))); \
| ^
/home/robert_sakana_ai/miniconda3/envs/llm2cuda/lib/python3.11/site-packages/torch/include/c10/util/Exception.h:536:9: note: expanded from macro 'TORCH_CHECK'
536 | __func__, \
| ^