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54_Conv2d_Multiply_LeakyReLU_GELUdynamic_block_size_54conv_base

Level 2 • Task 54
import torch
import torch.nn as nn
import torch.nn.functional as F


def module_fn(
    x: torch.Tensor,
    conv_weight: torch.Tensor,
    conv_bias: torch.Tensor,
    multiplier: torch.Tensor,
) -> torch.Tensor:
    """
    Applies convolution, scalar multiplication, LeakyReLU and GELU.

    Args:
        x (torch.Tensor): Input tensor of shape (batch_size, in_channels, height, width)
        conv_weight (torch.Tensor): Convolution weights of shape (out_channels, in_channels, kernel_size, kernel_size)
        conv_bias (torch.Tensor): Convolution bias of shape (out_channels)
        multiplier (torch.Tensor): Learnable scalar of shape (out_channels, 1, 1)

    Returns:
        torch.Tensor: Output tensor after applying convolution, multiplication, LeakyReLU and GELU
    """
    x = F.conv2d(x, conv_weight, bias=conv_bias)
    x = x * multiplier
    x = F.leaky_relu(x)
    x = F.gelu(x)
    return x


class Model(nn.Module):
    """
    Model that performs a convolution, multiplies by a learnable scalar, applies LeakyReLU, and then GELU.
    """

    def __init__(self, in_channels, out_channels, kernel_size, multiplier_shape):
        super(Model, self).__init__()
        conv = nn.Conv2d(in_channels, out_channels, kernel_size)
        self.conv_weight = nn.Parameter(conv.weight)
        self.conv_bias = nn.Parameter(conv.bias)
        self.multiplier = nn.Parameter(torch.randn(multiplier_shape) * 0.02)

    def forward(self, x, fn=module_fn):
        return fn(x, self.conv_weight, self.conv_bias, self.multiplier)


batch_size = 128
in_channels = 3
out_channels = 16
height, width = 32, 32
kernel_size = 3
multiplier_shape = (out_channels, 1, 1)


def get_inputs():
    return [torch.randn(batch_size, in_channels, height, width)]


def get_init_inputs():
    return [in_channels, out_channels, kernel_size, multiplier_shape]
import torch
import torch.nn as nn

class Model(nn.Module):
    """
    Model that performs a convolution, multiplies by a learnable scalar, applies LeakyReLU, and then GELU.
    """
    def __init__(self, in_channels, out_channels, kernel_size, multiplier_shape):
        super(Model, self).__init__()
        self.conv = nn.Conv2d(in_channels, out_channels, kernel_size)
        self.multiplier = nn.Parameter(torch.randn(multiplier_shape) * 0.02) 
        self.leaky_relu = nn.LeakyReLU()

    def forward(self, x):
        x = self.conv(x)
        x = x * self.multiplier
        x = self.leaky_relu(x)
        x = torch.nn.functional.gelu(x)
        return x

batch_size = 128
in_channels = 3
out_channels = 16
height, width = 32, 32
kernel_size = 3
multiplier_shape = (out_channels, 1, 1)

def get_inputs():
    return [torch.randn(batch_size, in_channels, height, width)]

def get_init_inputs():
    return [in_channels, out_channels, kernel_size, multiplier_shape]

Kernel Information

Related Kernels (Level 2, Task 54 • 54_Conv2d_Multiply_LeakyReLU_GELU)

Rank Kernel Name Runtime (ms) Speedup Native Speedup Compile
🥇 54_Conv2d_Multiply_LeakyReLU_GELU 0.04 1.28 1.44
🥇 balanced_workload_distribution_base 0.04 1.28 1.44
🥇 warp_divergence_optimized_base 0.04 1.28 1.44
🥇 optimized_block_size_128_base 0.04 1.28 1.44
🥇 optimized_convolution_with_tunable_blocksize_base 0.04 1.28 1.44
🥇 direct_3d_indexing_opt_base 0.04 1.28 1.44
🥇 direct_3d_indexing_base 0.04 1.28 1.44
🥇 unroll_loops_54conv_edit_1 0.04 1.28 1.44
🥇 dynamic_block_size_54conv_base 0.04 1.28 1.44
🥇 threadblock_3d_mapping_base 0.04 1.28 1.44
🥇 balanced_thread_distribution_base 0.04 1.28 1.44
🥇 branchless_no_divergence_54conv_base 0.04 1.28 1.44
🥇 modular_device_functions_base 0.04 1.28 1.44
🥇 tile_based_2d_indexing_base 0.04 1.28 1.44
15 combined_conv_act_base 0.04 1.25 1.40
15 optimized_stride_loop_base 0.04 1.25 1.40
15 unroll_loops_54conv_base 0.04 1.25 1.40
15 54_Conv2d_Multiply_LeakyReLU_GELU_warp_divergence_reduction_base 0.04 1.25 1.40
15 dynamic_block_size_54conv_edit_1 0.04 1.25 1.40
15 modular_device_functions_edit_1 0.04 1.25 1.40
#include <torch/extension.h>
#include <cuda.h>
#include <cuda_runtime.h>
#include <vector>
#include <cmath>
#include <stdio.h>

// Device function: GELU approximation
__device__ __forceinline__ float gelu(float x) {
    const float k0 = 0.7978845608028654f; // sqrt(2/pi)
    return 0.5f * x * (1.0f + tanhf(k0 * (x + 0.044715f * x * x * x)));
}

// CUDA kernel that performs convolution, scalar multiplication, LeakyReLU and GELU.
// - input: [batch_size, in_channels, input_h, input_w]
// - weight: [out_channels, in_channels, kernel_size, kernel_size]
// - bias: [out_channels]
// - multiplier: [out_channels] (broadcast over spatial dims)
// - output: [batch_size, out_channels, output_h, output_w]
__global__ void conv_forward_kernel(
    const float* __restrict__ input,
    const float* __restrict__ weight,
    const float* __restrict__ bias,
    const float* __restrict__ multiplier,
    float* __restrict__ output,
    int batch_size,
    int in_channels,
    int input_h,
    int input_w,
    int out_channels,
    int kernel_size,
    int output_h,
    int output_w
) {
    int idx = blockIdx.x * blockDim.x + threadIdx.x;
    int total = batch_size * out_channels * output_h * output_w;
    int stride = blockDim.x * gridDim.x;
    
    // Grid-stride loop to cover all output elements.
    for (int index = idx; index < total; index += stride) {
        // Calculate indices for output: (n, oc, oh, ow)
        int ow = index % output_w;
        int tmp = index / output_w;
        int oh = tmp % output_h;
        tmp = tmp / output_h;
        int oc = tmp % out_channels;
        int n = tmp / out_channels;

        // Start with the bias for output channel oc.
        float sum = bias[oc];
        
        // Convolution: iterate over input channels and kernel window.
        for (int ic = 0; ic < in_channels; ic++) {
            for (int i = 0; i < kernel_size; i++) {
                for (int j = 0; j < kernel_size; j++) {
                    int in_h = oh + i; // stride = 1, no padding
                    int in_w = ow + j;
                    int input_index = ((n * in_channels + ic) * input_h + in_h) * input_w + in_w;
                    int weight_index = ((oc * in_channels + ic) * kernel_size + i) * kernel_size + j;
                    sum += input[input_index] * weight[weight_index];
                }
            }
        }
        
        // Multiply with the channel-specific multiplier
        sum *= multiplier[oc];
        
        // Apply LeakyReLU activation (negative slope = 0.01)
        sum = (sum > 0.0f) ? sum : 0.01f * sum;
        
        // Apply GELU activation
        float out_val = gelu(sum);
        
        output[index] = out_val;
    }
}

// C++ interface (to be called from Python)
// Added parameter 'block_size' to allow experimentation with different block sizes (e.g., 32, 64, 128, 256, 512).
torch::Tensor forward_cuda(
    torch::Tensor input,
    torch::Tensor conv_weight,
    torch::Tensor conv_bias,
    torch::Tensor multiplier,
    int block_size = 256  // Default block size
) {
    // Get input dimensions
    const int batch_size = input.size(0);
    const int in_channels = input.size(1);
    const int input_h = input.size(2);
    const int input_w = input.size(3);
    
    // Get convolution parameters
    const int out_channels = conv_weight.size(0);
    const int kernel_size = conv_weight.size(2);
    const int output_h = input_h - kernel_size + 1;
    const int output_w = input_w - kernel_size + 1;
    
    // Allocate output tensor
    auto output = torch::empty({batch_size, out_channels, output_h, output_w}, input.options());
    
    // Calculate the total number of elements to process
    const int total_elements = batch_size * out_channels * output_h * output_w;
    int blocks = (total_elements + block_size - 1) / block_size;
    
    // Launch CUDA kernel with the specified block size
    conv_forward_kernel<<<blocks, block_size>>>(
        input.data_ptr<float>(),
        conv_weight.data_ptr<float>(),
        conv_bias.data_ptr<float>(),
        multiplier.data_ptr<float>(),
        output.data_ptr<float>(),
        batch_size,
        in_channels,
        input_h,
        input_w,
        out_channels,
        kernel_size,
        output_h,
        output_w
    );
    
    // Check for kernel launch errors
    cudaError_t err = cudaGetLastError();
    if (err != cudaSuccess) {
        printf("CUDA kernel failed: %s\n", cudaGetErrorString(err));
    }
    
    return output;
}

PYBIND11_MODULE(TORCH_EXTENSION_NAME, m) {
    m.def("forward", &forward_cuda, "Convolution, scalar multiplication, LeakyReLU and GELU (CUDA) with dynamic block size",
          py::arg("input"),
          py::arg("conv_weight"),
          py::arg("conv_bias"),
          py::arg("multiplier"),
          py::arg("block_size") = 256);
}
Performance Metrics
Metric Value Unit Variance Samples
Executed Ipc Active 3.174 inst/cycle 0.000 5
Executed Ipc Elapsed 2.948 inst/cycle 0.000 5
Issue Slots Busy 79.524 % 0.011 5
Issued Ipc Active 3.182 inst/cycle 0.000 5
SM Busy 79.524 % 0.011 5
Memory Throughput 35465307694.476 byte/second 18267120055705660.000 5
Mem Busy 53.260 % 0.051 5
Max Bandwidth 36.386 % 0.024 5
L1/TEX Hit Rate 87.932 % 0.000 5
L2 Hit Rate 92.528 % 0.058 5
Mem Pipes Busy 35.864 % 0.023 5
Warp Cycles Per Issued Instruction 16.718 cycle 0.000 5
Warp Cycles Per Executed Instruction 16.758 cycle 0.000 5
Avg. Active Threads Per Warp 32.000 0.000 5
Avg. Not Predicated Off Threads Per Warp 29.300 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 8.000 block 0.000 5
Block Limit Shared Mem 32.000 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 83.396 % 0.007 5
Achieved Active Warps Per SM 53.372 warp 0.003 5
Analysis Rules
Rule Description
INF HighPipeUtilization ALU is the highest-utilized pipeline (45.3%) based on active cycles, taking into account the rates of its different instructions. It executes integer and logic 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 (83.3%) 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.
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.
Operation / Metric Value Unit
aten::to
CPU Time 273281.13 μs
Device Time 81.41 μs
Self CPU Time 60.83 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 273220.31 μs
Device Time 81.41 μs
Self CPU Time 115.35 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 272733.99 μs
Device Time 0.00 μs
Self CPU Time 135.75 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 272196.69 μs
Device Time 0.00 μs
Self CPU Time 272196.69 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 634183.26 μs
Device Time 14806.58 μs
Self CPU Time 634183.26 μs
Self Device Time 14806.58 μs
CPU Memory Usage 0 B
Device Memory Usage 0 B
Self CPU Memory Usage 0 B
Self Device Memory Usage 0 B
conv_forward_kernel(float const*, float const*, float const*, float const*, float*, int, int, int, int, int, int, int, int)
CPU Time 0.00 μs
Device Time 259177.32 μs
Self CPU Time 0.00 μs
Self Device Time 259177.32 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 19900.72 μs
Device Time 28907.56 μs
Self CPU Time 19900.72 μs
Self Device Time 28907.56 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 219910.49 μs
Device Time 556300.08 μs
Self CPU Time 12885.56 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 207026.92 μs
Device Time 556300.08 μs
Self CPU Time 15366.92 μs
Self Device Time 556300.08 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 556300.08 μs
Self CPU Time 0.00 μs
Self Device Time 556300.08 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
45293 warnings generated when compiling for host.
Suppressed 45325 warnings (45278 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_54/b4_s0_dynamic_block_size_54conv/base/base.cu:22:5 bugprone-easily-swappable-parameters
22 | const float* __restrict__ weight,
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
23 | const float* __restrict__ bias,
| ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
24 | const float* __restrict__ multiplier,
| ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/home/robert_sakana_ai/llm_cuda/experiments/20250212_optimize_b5_s4_e1_v2/level_2/task_54/b4_s0_dynamic_block_size_54conv/base/base.cu:22:31: note: the first parameter in the range is 'weight'
22 | const float* __restrict__ weight,
| ^~~~~~
/home/robert_sakana_ai/llm_cuda/experiments/20250212_optimize_b5_s4_e1_v2/level_2/task_54/b4_s0_dynamic_block_size_54conv/base/base.cu:24:31: note: the last parameter in the range is 'multiplier'
24 | const float* __restrict__ multiplier,
| ^~~~~~~~~~
/home/robert_sakana_ai/llm_cuda/experiments/20250212_optimize_b5_s4_e1_v2/level_2/task_54/b4_s0_dynamic_block_size_54conv/base/base.cu:26:5: warning: 2 adjacent parameters of 'conv_forward_kernel' of similar type ('int') are easily swapped by mistake [bugprone-easily-swappable-parameters]
26 | int batch_size,
| ^~~~~~~~~~~~~~~
27 | int in_channels,
| ~~~~~~~~~~~~~~~
/home/robert_sakana_ai/llm_cuda/experiments/20250212_optimize_b5_s4_e1_v2/level_2/task_54/b4_s0_dynamic_block_size_54conv/base/base.cu:26:9: note: the first parameter in the range is 'batch_size'
26 | int batch_size,
| ^~~~~~~~~~
/home/robert_sakana_ai/llm_cuda/experiments/20250212_optimize_b5_s4_e1_v2/level_2/task_54/b4_s0_dynamic_block_size_54conv/base/base.cu:27:9: note: the last parameter in the range is 'in_channels'
27 | int in_channels,
| ^~~~~~~~~~~
/home/robert_sakana_ai/llm_cuda/experiments/20250212_optimize_b5_s4_e1_v2/level_2/task_54/b4_s0_dynamic_block_size_54conv/base/base.cu:29:5: warning: 3 adjacent parameters of 'conv_forward_kernel' of similar type ('int') are easily swapped by mistake [bugprone-easily-swappable-parameters]
29 | int input_w,
| ^~~~~~~~~~~~
30 | int out_channels,
| ~~~~~~~~~~~~~~~~~
31 | int kernel_size,
| ~~~~~~~~~~~~~~~
/home/robert_sakana_ai/llm_cuda/experiments/20250212_optimize_b5_s4_e1_v2/level_2/task_54/b4_s0_dynamic_block_size_54conv/base/base.cu:29:9: note: the first parameter in the range is 'input_w'
29 | int input_w,
| ^~~~~~~
/home/robert_sakana_ai/llm_cuda/experiments/20250212_optimize_b5_s4_e1_v2/level_2/task_54/b4_s0_dynamic_block_size_54conv/base/base.cu:31:9: note: the last parameter in the range is 'kernel_size'
31 | int kernel_size,
| ^~~~~~~~~~~
/home/robert_sakana_ai/llm_cuda/experiments/20250212_optimize_b5_s4_e1_v2/level_2/task_54/b4_s0_dynamic_block_size_54conv/base/base.cu:35:15: warning: narrowing conversion from 'unsigned int' to signed type 'int' is implementation-defined [bugprone-narrowing-conversions]
35 | int idx = blockIdx.x * blockDim.x + threadIdx.x;
| ^
/home/robert_sakana_ai/llm_cuda/experiments/20250212_optimize_b5_s4_e1_v2/level_2/task_54/b4_s0_dynamic_block_size_54conv/base/base.cu:37:18: warning: narrowing conversion from 'unsigned int' to signed type 'int' is implementation-defined [bugprone-narrowing-conversions]
37 | int stride = blockDim.x * gridDim.x;
| ^
/home/robert_sakana_ai/llm_cuda/experiments/20250212_optimize_b5_s4_e1_v2/level_2/task_54/b4_s0_dynamic_block_size_54conv/base/base.cu:81:19: warning: the parameter 'input' is copied for each invocation but only used as a const reference; consider making it a const reference [performance-unnecessary-value-param]
81 | torch::Tensor input,
| ^
| const &
/home/robert_sakana_ai/llm_cuda/experiments/20250212_optimize_b5_s4_e1_v2/level_2/task_54/b4_s0_dynamic_block_size_54conv/base/base.cu:82:19: warning: the parameter 'conv_weight' is copied for each invocation but only used as a const reference; consider making it a const reference [performance-unnecessary-value-param]
82 | torch::Tensor conv_weight,
| ^
| const &
/home/robert_sakana_ai/llm_cuda/experiments/20250212_optimize_b5_s4_e1_v2/level_2/task_54/b4_s0_dynamic_block_size_54conv/base/base.cu:83:19: warning: the parameter 'conv_bias' is copied for each invocation but only used as a const reference; consider making it a const reference [performance-unnecessary-value-param]
83 | torch::Tensor conv_bias,
| ^
| const &
/home/robert_sakana_ai/llm_cuda/experiments/20250212_optimize_b5_s4_e1_v2/level_2/task_54/b4_s0_dynamic_block_size_54conv/base/base.cu:84:19: warning: the parameter 'multiplier' is copied for each invocation but only used as a const reference; consider making it a const reference [performance-unnecessary-value-param]
84 | torch::Tensor multiplier,
| ^
| const &
/home/robert_sakana_ai/llm_cuda/experiments/20250212_optimize_b5_s4_e1_v2/level_2/task_54/b4_s0_dynamic_block_size_54conv/base/base.cu:88:28: warning: narrowing conversion from 'int64_t' (aka 'long') to signed type 'int' is implementation-defined [bugprone-narrowing-conversions]
88 | const int batch_size = input.size(0);
| ^
/home/robert_sakana_ai/llm_cuda/experiments/20250212_optimize_b5_s4_e1_v2/level_2/task_54/b4_s0_dynamic_block_size_54conv/base/base.cu:89:29: warning: narrowing conversion from 'int64_t' (aka 'long') to signed type 'int' is implementation-defined [bugprone-narrowing-conversions]
89 | const int in_channels = input.size(1);
| ^
/home/robert_sakana_ai/llm_cuda/experiments/20250212_optimize_b5_s4_e1_v2/level_2/task_54/b4_s0_dynamic_block_size_54conv/base/base.cu:90:25: warning: narrowing conversion from 'int64_t' (aka 'long') to signed type 'int' is implementation-defined [bugprone-narrowing-conversions]
90 | const int input_h = input.size(2);
| ^
/home/robert_sakana_ai/llm_cuda/experiments/20250212_optimize_b5_s4_e1_v2/level_2/task_54/b4_s0_dynamic_block_size_54conv/base/base.cu:91:25: warning: narrowing conversion from 'int64_t' (aka 'long') to signed type 'int' is implementation-defined [bugprone-narrowing-conversions]
91 | const int input_w = input.size(3);
| ^
/home/robert_sakana_ai/llm_cuda/experiments/20250212_optimize_b5_s4_e1_v2/level_2/task_54/b4_s0_dynamic_block_size_54conv/base/base.cu:94:30: warning: narrowing conversion from 'int64_t' (aka 'long') to signed type 'int' is implementation-defined [bugprone-narrowing-conversions]
94 | const int out_channels = conv_weight.size(0);
| ^
/home/robert_sakana_ai/llm_cuda/experiments/20250212_optimize_b5_s4_e1_v2/level_2/task_54/b4_s0_dynamic_block_size_54conv/base/base.cu:95:29: warning: narrowing conversion from 'int64_t' (aka 'long') to signed type 'int' is implementation-defined [bugprone-narrowing-conversions]
95 | const int kernel_size = conv_weight.size(2);
| ^