115 lines
4.3 KiB
C++
115 lines
4.3 KiB
C++
/******************************************************************************
|
|
* Copyright (c) 2023, Tri Dao.
|
|
******************************************************************************/
|
|
|
|
// Host entry point for the fused RMS-norm + RoPE kernel.
|
|
|
|
#include <ATen/cuda/CUDAContext.h>
|
|
#include <c10/cuda/CUDAGuard.h>
|
|
#include <torch/extension.h>
|
|
#include <vector>
|
|
|
|
#include "fast_hadamard_transform.h"
|
|
|
|
#define CHECK_SHAPE(x, ...) TORCH_CHECK(x.sizes() == torch::IntArrayRef({__VA_ARGS__}), #x " must have shape (" #__VA_ARGS__ ")")
|
|
|
|
template<typename input_t, typename output_t, bool norm_affine>
|
|
void rms_norm_rope_cuda(NormRopeHadamardParamsBase ¶ms, cudaStream_t stream);
|
|
|
|
void set_norm_rope_hadamard_params(NormRopeHadamardParamsBase ¶ms,
|
|
// sizes
|
|
const size_t batch,
|
|
const size_t dim,
|
|
const size_t multiple,
|
|
// device pointers
|
|
const at::Tensor x,
|
|
const at::Tensor cos_freqs,
|
|
const at::Tensor sin_freqs,
|
|
const at::Tensor weights,
|
|
const at::Tensor out,
|
|
|
|
bool norm_affine,
|
|
float scale
|
|
) {
|
|
|
|
// Reset the parameters
|
|
memset(¶ms, 0, sizeof(params));
|
|
|
|
params.batch = batch;
|
|
params.dim = dim;
|
|
params.log_N = int(ceil(std::log2(dim / multiple)));
|
|
|
|
// Set the pointers and strides.
|
|
params.x_ptr = x.data_ptr();
|
|
params.out_ptr = out.data_ptr();
|
|
params.cos_freq_ptr = cos_freqs.data_ptr();
|
|
params.sin_freq_ptr = sin_freqs.data_ptr();
|
|
if (norm_affine){
|
|
params.weights_ptr = weights.data_ptr();
|
|
} else {
|
|
params.weights_ptr = nullptr;
|
|
}
|
|
// All stride are in elements, not bytes.
|
|
params.x_batch_stride = x.stride(0);
|
|
params.out_batch_stride = out.stride(0);
|
|
params.cos_freq_batch_stride = cos_freqs.stride(0);
|
|
params.sin_freq_batch_stride = sin_freqs.stride(0);
|
|
|
|
params.scale = scale;
|
|
|
|
}
|
|
|
|
at::Tensor rms_norm_rope(at::Tensor &x, c10::optional<at::Tensor>& weights_, at::Tensor &cos_freqs, at::Tensor &sin_freqs, bool out_16bit) {
|
|
auto input_type = x.scalar_type();
|
|
float scale = 1.0f; // :D
|
|
TORCH_CHECK(input_type == at::ScalarType::BFloat16);
|
|
TORCH_CHECK(x.is_cuda());
|
|
const auto shapes_og = x.sizes();
|
|
const int dim_og = x.size(-1);
|
|
x = x.reshape({-1, dim_og});
|
|
if (x.stride(-1) != 1) { x = x.contiguous(); }
|
|
const auto sizes = x.sizes();
|
|
const int batch_size = sizes[0];
|
|
cos_freqs = cos_freqs.reshape({-1, dim_og});
|
|
sin_freqs = sin_freqs.reshape({-1, dim_og});
|
|
at::Tensor weights;
|
|
bool norm_affine = false;
|
|
if(weights_.has_value()){
|
|
weights = weights_.value();
|
|
norm_affine = true;
|
|
}
|
|
CHECK_SHAPE(x, batch_size, dim_og);
|
|
TORCH_CHECK(x.stride(1) == 1);
|
|
if (dim_og % 8 != 0) {
|
|
x = torch::nn::functional::pad(x, torch::nn::functional::PadFuncOptions({0, 8 - dim_og % 8}));
|
|
}
|
|
const int dim = x.size(1);
|
|
at::Tensor out;
|
|
if (out_16bit){
|
|
out = torch::empty(x.sizes(), x.options().dtype(torch::kBFloat16));
|
|
} else {
|
|
out = torch::empty(x.sizes(), x.options().dtype(torch::kFloat8_e4m3fn));
|
|
}
|
|
at::cuda::CUDAGuard device_guard{(char)x.get_device()};
|
|
auto stream = at::cuda::getCurrentCUDAStream().stream();
|
|
NormRopeHadamardParamsBase params;
|
|
set_norm_rope_hadamard_params(params, batch_size, dim, 1, x, cos_freqs, sin_freqs, weights, out, norm_affine, scale);
|
|
TORCH_CHECK(dim % 8 == 0, "fast_hadamard_transform only supports hidden dimension divisible by 8 for now");
|
|
TORCH_CHECK(dim <= 32768, "fast_hadamard_transform only supports hidden dimension at most 32768 for now");
|
|
if (norm_affine){
|
|
if (out_16bit){
|
|
rms_norm_rope_cuda<at::BFloat16, at::BFloat16, true>(params, stream);
|
|
} else {
|
|
rms_norm_rope_cuda<at::BFloat16, at::Float8_e4m3fn, true>(params, stream);
|
|
}
|
|
|
|
} else {
|
|
if (out_16bit){
|
|
rms_norm_rope_cuda<at::BFloat16, at::BFloat16, false>(params, stream);
|
|
} else {
|
|
rms_norm_rope_cuda<at::BFloat16, at::Float8_e4m3fn, false>(params, stream);
|
|
}
|
|
}
|
|
return out.reshape(shapes_og);
|
|
}
|