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90_Conv3d_LeakyReLU_Sum_Clamp_GELUmultidim_indexed_kernel_base

Level 2 • Task 90
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,
    sum_tensor: torch.Tensor,
) -> torch.Tensor:
    """
    Applies 3D convolution, LeakyReLU, tensor addition, clamping and GELU activation.

    Args:
        x (torch.Tensor): Input tensor of shape (batch_size, in_channels, depth, height, width)
        conv_weight (torch.Tensor): 3D convolution weight tensor of shape
            (out_channels, in_channels, kernel_size, kernel_size, kernel_size)
        conv_bias (torch.Tensor): Bias tensor for 3D convolution of shape (out_channels)
        sum_tensor (torch.Tensor): Tensor to add of shape (out_channels, 1, 1, 1)

    Returns:
        torch.Tensor: Output tensor after applying convolution, LeakyReLU, addition,
            clamping and GELU activation
    """
    x = F.conv3d(x, conv_weight, bias=conv_bias)
    x = F.leaky_relu(x, negative_slope=0.2)
    x = x + sum_tensor
    x = torch.clamp(x, min=-1.0, max=1.0)
    x = F.gelu(x)
    return x


class Model(nn.Module):
    """
    Model that performs a 3D convolution, applies LeakyReLU, sums with a tensor, clamps, and applies GELU activation.
    """

    def __init__(self, in_channels, out_channels, kernel_size, sum_tensor_shape):
        super(Model, self).__init__()
        conv = nn.Conv3d(in_channels, out_channels, kernel_size)
        self.conv_weight = conv.weight
        self.conv_bias = conv.bias
        self.sum_tensor = nn.Parameter(torch.randn(sum_tensor_shape) * 0.02)

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


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


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


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

class Model(nn.Module):
    """
    Model that performs a 3D convolution, applies LeakyReLU, sums with a tensor, clamps, and applies GELU activation.
    """
    def __init__(self, in_channels, out_channels, kernel_size, sum_tensor_shape):
        super(Model, self).__init__()
        self.conv = nn.Conv3d(in_channels, out_channels, kernel_size)
        self.sum_tensor = nn.Parameter(torch.randn(sum_tensor_shape)*0.02)

    def forward(self, x):
        x = self.conv(x)
        x = torch.nn.functional.leaky_relu(x, negative_slope=0.2)
        x = x + self.sum_tensor
        x = torch.clamp(x, min=-1.0, max=1.0)
        x = torch.nn.functional.gelu(x)
        return x

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

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

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

Kernel Information

Related Kernels (Level 2, Task 90 • 90_Conv3d_LeakyReLU_Sum_Clamp_GELU)

Rank Kernel Name Runtime (ms) Speedup Native Speedup Compile
🥇 aligned_vectorized_ldg_90_conv3d_edit_1 0.79 1.25 0.66
🥈 aligned_vectorized_ldg_90_conv3d_base 0.80 1.24 0.66
🥉 modular_device_functions_base 0.81 1.21 0.65
🥉 load_balanced_kernel_base_base 0.81 1.21 0.65
5 constant_memory_optimization_base 0.82 1.21 0.65
6 coalesced_mem_access_opt_base 0.82 1.20 0.64
7 atomic_minimal_usage_kernel_opt_base 0.83 1.20 0.64
7 atomic_minimal_usage_kernel_opt_edit_1 0.83 1.20 0.64
9 modular_device_functions_v2_base 0.83 1.20 0.64
10 balanced_workload_distribution_base 0.83 1.19 0.64
11 warp_primitives_based_kernel_edit_1 0.83 1.19 0.63
12 optimized_strided_loop_base_base 0.83 1.19 0.63
13 gridstride_const_base 0.84 1.18 0.63
13 block_size_256_kernel_base 0.84 1.18 0.63
15 warp_divergence_free_base 0.84 1.18 0.63
15 modular_device_functions_base 0.84 1.18 0.63
17 optimized_kernel_combination_base 0.84 1.18 0.63
18 multidim_indexed_kernel_base 0.84 1.18 0.63
18 const_mem_conv3d_leakyrelu_sumclamp_gelu_base 0.84 1.18 0.63
20 90_Conv3d_LeakyReLU_Sum_Clamp_GELU 0.84 1.17 0.63
#include <torch/extension.h>
#include <ATen/ATen.h>
#include <vector>
#include <cmath>

// Inline device function for LeakyReLU
__device__ inline float leaky_relu(float x, float alpha = 0.2f) {
    return (x > 0.0f) ? x : alpha * x;
}

// Inline device function for clamping
__device__ inline float clamp_val(float x, float min_val = -1.0f, float max_val = 1.0f) {
    return fmaxf(fminf(x, max_val), min_val);
}

// Inline device function for GELU activation using tanh approximation
__device__ inline float gelu(float x) {
    float tanh_out = tanhf(0.7978845608f * (x + 0.044715f * x * x * x));
    return x * 0.5f * (1.0f + tanh_out);
}

// CUDA kernel using 3D grid mapping for spatial and (batch,channel,depth) dimensions
__global__ void multi_dim_kernel(
    const float* __restrict__ input,
    const float* __restrict__ sum_tensor,
    float* __restrict__ output,
    int B,
    int C,
    int D,
    int H,
    int W) {

    // Map spatial dimensions (width, height) using blockIdx.x and blockIdx.y
    int w = blockIdx.x * blockDim.x + threadIdx.x;
    int h = blockIdx.y * blockDim.y + threadIdx.y;
    
    // Use gridDim.z to cover combined (B, C, D):
    // Let each grid.z index represent a unique combination of (b, c, d)
    int z_idx = blockIdx.z; // runs from 0 to (B * C * D - 1)
    int d = z_idx % D;       // depth index
    int bc = z_idx / D;      // combined batch and channel index
    int b = bc / C;          // batch index
    int c = bc % C;          // channel index
    
    // Check bounds for spatial dimensions
    if (w < W && h < H) {
        // Compute linear index for contiguous tensor in [B, C, D, H, W] layout
        int idx = (((b * C + c) * D + d) * H + h) * W + w;
        
        float x = input[idx];
        float y = leaky_relu(x);
        y += sum_tensor[c];
        y = clamp_val(y);
        y = gelu(y);
        
        output[idx] = y;
    }
}

// Kernel launcher that sets up a 3D grid mapping the tensor dimensions
void multi_dim_kernel_launcher(torch::Tensor &x, torch::Tensor &sum_tensor) {
    int B = x.size(0);
    int C = x.size(1);
    int D = x.size(2);
    int H = x.size(3);
    int W = x.size(4);

    // Choose block dimensions for the spatial axes
    const int BLOCK_W = 16;
    const int BLOCK_H = 16;
    dim3 block(BLOCK_W, BLOCK_H, 1);

    // Grid dimensions:
    // - grid.x covers width
    // - grid.y covers height
    // - grid.z covers the combined (B, C, D) dimensions
    int grid_x = (W + BLOCK_W - 1) / BLOCK_W;
    int grid_y = (H + BLOCK_H - 1) / BLOCK_H;
    int grid_z = B * C * D;  
    dim3 grid(grid_x, grid_y, grid_z);

    multi_dim_kernel<<<grid, block>>>(
        x.data_ptr<float>(), 
        sum_tensor.data_ptr<float>(), 
        x.data_ptr<float>(), 
        B, C, D, H, W);
    cudaDeviceSynchronize();
}

// Forward function: performs 3D convolution then applies our elementwise CUDA kernel
torch::Tensor forward(
    torch::Tensor x,
    torch::Tensor conv_weight,
    torch::Tensor conv_bias,
    torch::Tensor sum_tensor) {

    TORCH_CHECK(x.is_cuda(), "x must be a CUDA tensor");
    TORCH_CHECK(conv_weight.is_cuda(), "conv_weight must be a CUDA tensor");
    TORCH_CHECK(conv_bias.is_cuda(), "conv_bias must be a CUDA tensor");
    TORCH_CHECK(sum_tensor.is_cuda(), "sum_tensor must be a CUDA tensor");
    TORCH_CHECK(x.scalar_type() == at::kFloat, "x must be float32");

    // Perform 3D convolution
    auto x_conv = at::conv3d(x, conv_weight, conv_bias);

    // Ensure the tensor is contiguous
    auto output = x_conv.contiguous();

    // Launch the CUDA kernel with multi-dimensional grid and block indexing
    multi_dim_kernel_launcher(output, sum_tensor);

    return output;
}

PYBIND11_MODULE(TORCH_EXTENSION_NAME, m) {
    m.def("forward", &forward, "Multi-dim indexed Conv3d LeakyReLU Sum Clamp GELU forward (CUDA)");
}
Performance Metrics
Metric Value Unit Variance Samples
Executed Ipc Active 3.140 inst/cycle 0.000 5
Executed Ipc Elapsed 3.090 inst/cycle 0.000 5
Issue Slots Busy 78.502 % 0.006 5
Issued Ipc Active 3.140 inst/cycle 0.000 5
SM Busy 78.502 % 0.006 5
Memory Throughput 1214948389363.868 byte/second 3520433275614237696.000 5
Mem Busy 29.408 % 0.003 5
Max Bandwidth 38.926 % 0.004 5
L1/TEX Hit Rate 53.216 % 0.000 5
L2 Hit Rate 68.916 % 0.010 5
Mem Pipes Busy 49.738 % 0.007 5
Warp Cycles Per Issued Instruction 15.736 cycle 0.000 5
Warp Cycles Per Executed Instruction 15.738 cycle 0.001 5
Avg. Active Threads Per Warp 27.670 0.000 5
Avg. Not Predicated Off Threads Per Warp 24.960 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 16.000 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 78.120 % 0.000 5
Achieved Active Warps Per SM 49.996 warp 0.000 5
Analysis Rules
Rule Description
INF HighPipeUtilization ALU is the highest-utilized pipeline (54.3%) 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.
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 (78.1%) 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 470000.28 μs
Device Time 2732.40 μs
Self CPU Time 54.30 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 469945.98 μs
Device Time 2732.40 μs
Self CPU Time 118.99 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 466748.89 μs
Device Time 0.00 μs
Self CPU Time 132.53 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::conv3d
CPU Time 444392.00 μs
Device Time 4829856.74 μs
Self CPU Time 14329.86 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::convolution
CPU Time 430062.14 μs
Device Time 4829856.74 μs
Self CPU Time 20919.79 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::_convolution
CPU Time 409142.36 μs
Device Time 4829856.74 μs
Self CPU Time 40295.99 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::cudnn_convolution
CPU Time 281167.91 μs
Device Time 4187134.79 μs
Self CPU Time 203679.04 μs
Self Device Time 4187134.79 μs
CPU Memory Usage 0 B
Device Memory Usage 0 B
Self CPU Memory Usage 0 B
Self Device Memory Usage 0 B
sm80_xmma_fprop_implicit_gemm_indexed_f32f32_f32f32_f32_nchwkcrs_nchw_tilesize32x32x8_stage3_warpsize1x2x1_g1_ffma_aligna4_alignc4_execute_kernel__5x_cudnn
CPU Time 0.00 μs
Device Time 4187132.17 μs
Self CPU Time 0.00 μs
Self Device Time 4187132.17 μs
CPU Memory Usage 0 B
Device Memory Usage 0 B
Self CPU Memory Usage 0 B
Self Device Memory Usage 0 B
cudaDeviceSynchronize
CPU Time 5983533.02 μs
Device Time 106911.04 μs
Self CPU Time 5983533.02 μs
Self Device Time 106911.04 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
45289 warnings generated when compiling for host.
Suppressed 45324 warnings (45277 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/20250203_optimize_b10_s4_e0_sweep/level_2/task_90/b6_s3_multidim_indexed_kernel/base/base.cu:24:5 bugprone-easily-swappable-parameters
24 | const float* __restrict__ input,
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
25 | const float* __restrict__ sum_tensor,
| ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/home/robert_sakana_ai/llm_cuda/experiments/20250203_optimize_b10_s4_e0_sweep/level_2/task_90/b6_s3_multidim_indexed_kernel/base/base.cu:24:31: note: the first parameter in the range is 'input'
24 | const float* __restrict__ input,
| ^~~~~
/home/robert_sakana_ai/llm_cuda/experiments/20250203_optimize_b10_s4_e0_sweep/level_2/task_90/b6_s3_multidim_indexed_kernel/base/base.cu:25:31: note: the last parameter in the range is 'sum_tensor'
25 | const float* __restrict__ sum_tensor,
| ^~~~~~~~~~
/home/robert_sakana_ai/llm_cuda/experiments/20250203_optimize_b10_s4_e0_sweep/level_2/task_90/b6_s3_multidim_indexed_kernel/base/base.cu:27:5: warning: 2 adjacent parameters of 'multi_dim_kernel' of similar type ('int') are easily swapped by mistake [bugprone-easily-swappable-parameters]
27 | int B,
| ^~~~~~
28 | int C,
| ~~~~~
/home/robert_sakana_ai/llm_cuda/experiments/20250203_optimize_b10_s4_e0_sweep/level_2/task_90/b6_s3_multidim_indexed_kernel/base/base.cu:27:9: note: the first parameter in the range is 'B'
27 | int B,
| ^
/home/robert_sakana_ai/llm_cuda/experiments/20250203_optimize_b10_s4_e0_sweep/level_2/task_90/b6_s3_multidim_indexed_kernel/base/base.cu:28:9: note: the last parameter in the range is 'C'
28 | int C,
| ^
/home/robert_sakana_ai/llm_cuda/experiments/20250203_optimize_b10_s4_e0_sweep/level_2/task_90/b6_s3_multidim_indexed_kernel/base/base.cu:34:13: warning: narrowing conversion from 'unsigned int' to signed type 'int' is implementation-defined [bugprone-narrowing-conversions]
34 | int w = blockIdx.x * blockDim.x + threadIdx.x;
| ^
/home/robert_sakana_ai/llm_cuda/experiments/20250203_optimize_b10_s4_e0_sweep/level_2/task_90/b6_s3_multidim_indexed_kernel/base/base.cu:35:13: warning: narrowing conversion from 'unsigned int' to signed type 'int' is implementation-defined [bugprone-narrowing-conversions]
35 | int h = blockIdx.y * blockDim.y + threadIdx.y;
| ^
/home/robert_sakana_ai/llm_cuda/experiments/20250203_optimize_b10_s4_e0_sweep/level_2/task_90/b6_s3_multidim_indexed_kernel/base/base.cu:39:17: warning: narrowing conversion from 'unsigned int' to signed type 'int' is implementation-defined [bugprone-narrowing-conversions]
39 | int z_idx = blockIdx.z; // runs from 0 to (B * C * D - 1)
| ^
/home/robert_sakana_ai/llm_cuda/experiments/20250203_optimize_b10_s4_e0_sweep/level_2/task_90/b6_s3_multidim_indexed_kernel/base/base.cu:62:13: warning: narrowing conversion from 'int64_t' (aka 'long') to signed type 'int' is implementation-defined [bugprone-narrowing-conversions]
62 | int B = x.size(0);
| ^
/home/robert_sakana_ai/llm_cuda/experiments/20250203_optimize_b10_s4_e0_sweep/level_2/task_90/b6_s3_multidim_indexed_kernel/base/base.cu:63:13: warning: narrowing conversion from 'int64_t' (aka 'long') to signed type 'int' is implementation-defined [bugprone-narrowing-conversions]
63 | int C = x.size(1);
| ^
/home/robert_sakana_ai/llm_cuda/experiments/20250203_optimize_b10_s4_e0_sweep/level_2/task_90/b6_s3_multidim_indexed_kernel/base/base.cu:64:13: warning: narrowing conversion from 'int64_t' (aka 'long') to signed type 'int' is implementation-defined [bugprone-narrowing-conversions]
64 | int D = x.size(2);
| ^
/home/robert_sakana_ai/llm_cuda/experiments/20250203_optimize_b10_s4_e0_sweep/level_2/task_90/b6_s3_multidim_indexed_kernel/base/base.cu:65:13: warning: narrowing conversion from 'int64_t' (aka 'long') to signed type 'int' is implementation-defined [bugprone-narrowing-conversions]
65 | int H = x.size(3);
| ^
/home/robert_sakana_ai/llm_cuda/experiments/20250203_optimize_b10_s4_e0_sweep/level_2/task_90/b6_s3_multidim_indexed_kernel/base/base.cu:66:13: warning: narrowing conversion from 'int64_t' (aka 'long') to signed type 'int' is implementation-defined [bugprone-narrowing-conversions]
66 | int W = x.size(4);
| ^
/home/robert_sakana_ai/llm_cuda/experiments/20250203_optimize_b10_s4_e0_sweep/level_2/task_90/b6_s3_multidim_indexed_kernel/base/base.cu:92:19: warning: the parameter 'x' is copied for each invocation but only used as a const reference; consider making it a const reference [performance-unnecessary-value-param]
92 | torch::Tensor x,
| ^
| const &
/home/robert_sakana_ai/llm_cuda/experiments/20250203_optimize_b10_s4_e0_sweep/level_2/task_90/b6_s3_multidim_indexed_kernel/base/base.cu:93:19: 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]
93 | torch::Tensor conv_weight,
| ^
| const &