You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.

173 lines
7.0 KiB

#if !defined(TORCH_STABLE_ONLY) && !defined(TORCH_TARGET_VERSION)
#pragma once
#include <ATen/core/Tensor.h>
#include <ATen/TensorUtils.h>
#ifndef AT_PER_OPERATOR_HEADERS
#include <ATen/CPUFunctions.h>
#include <ATen/Functions.h>
#include <ATen/NativeFunctions.h>
#else
#include <ATen/ops/bmm.h>
#include <ATen/ops/empty.h>
#include <ATen/ops/empty_strided.h>
#include <ATen/ops/mm.h>
#endif
namespace at::native {
inline bool check_valid_strides_and_return_transposed(const Tensor& mat) {
IntArrayRef tensor_strides = mat.strides();
IntArrayRef tensor_sizes = mat.sizes();
int end_dim = mat.dim() - 1;
int alignment = 16 / mat.element_size();
TORCH_CHECK(uint64_t(mat.data_ptr()) % 16 ==0, "expected data_ptr to be aligned to 16 bytes\n");
if ((tensor_strides[end_dim - 1] == 1) && (tensor_strides[end_dim] >= std::max<int64_t>(1, tensor_sizes[end_dim - 1]))) {
TORCH_CHECK(tensor_strides[end_dim] % alignment == 0, "strides should be multiple of 16 bytes");
return true;
} else if ((tensor_strides[end_dim] == 1) && (tensor_strides[end_dim - 1] >= std::max<int64_t>(1, tensor_sizes[end_dim]))) {
TORCH_CHECK(tensor_strides[end_dim - 1] % alignment == 0, "strides should be multiple of 16 bytes");
return false;
} else {
TORCH_CHECK(false, "Invalid strides/sizes, got ", mat.strides(), " for strides and ", mat.sizes(), " for sizes");
}
}
inline at::Tensor create_grouped_gemm_output_tensor(const Tensor& mat_a,
const Tensor& mat_b,
const std::optional<at::Tensor>& offs,
c10::ScalarType out_dtype
) {
c10::SmallVector<int64_t, 3> out_size;
const bool a_is_2d = mat_a.dim() == 2;
const bool b_is_2d = mat_b.dim() == 2;
if (a_is_2d) {
if (b_is_2d) {
out_size = {offs->size(0), mat_a.size(0), mat_b.size(1)};
} else {
TORCH_CHECK(offs->size(0) == mat_b.size(0), "matrix batch sizes have to match");
out_size = {mat_a.size(0), mat_b.size(-1)};
}
} else {
if (b_is_2d) {
// this case is not actually encountered for MoE gemms
TORCH_CHECK(offs->size(0) == mat_a.size(0), "matrix batch sizes have to match");
out_size = {mat_a.size(1), mat_b.size(1)};
} else { // regular bmm
TORCH_CHECK(mat_a.size(0) == mat_b.size(0), "batched dimension has to match");
out_size = {mat_a.size(0), mat_a.size(1), mat_b.size(-1)};
}
}
#ifndef USE_ROCM
// For TMA transfers, strides of output tensor have to be either
// 1, or aligned to 16 bytes.
const auto last_dim = out_size.size() - 1;
const auto alignment = 16 / c10::elementSize(out_dtype);
const int64_t size_padded = (out_size[last_dim] + alignment - 1) / alignment * alignment;
std::vector<int64_t> out_stride;
if (a_is_2d != b_is_2d) {
out_stride = {size_padded, 1};
} else {
out_stride = {out_size[1] * size_padded, size_padded, 1};
}
return at::empty_strided(out_size, out_stride, mat_a.options().dtype(out_dtype));
#else
return at::empty(out_size, mat_a.options().dtype(out_dtype));
#endif
}
inline void _grouped_mm_validate_inputs(const Tensor& mat_a, const Tensor& mat_b,
const std::optional<at::Tensor>& offs,
const std::optional<at::Tensor>& bias,
std::optional<c10::ScalarType> out_dtype) {
TORCH_CHECK((mat_a.dtype() == at::kBFloat16) || (mat_a.dtype() == at::kFloat) || (mat_a.dtype() == at::kHalf), "Expected mat_a to be Float32, BFloat16 or Float16 matrix, got ", mat_a.scalar_type());
TORCH_CHECK((mat_b.dtype() == at::kBFloat16) || (mat_b.dtype() == at::kFloat) || (mat_b.dtype() == at::kHalf), "Expected mat_b to be Float32, BFloat16 or Float16 matrix, got ", mat_b.scalar_type());
TORCH_CHECK(mat_a.dim() == 2 || mat_a.dim() == 3, "mat_a has to be 2 or 3d");
TORCH_CHECK(mat_b.dim() == 2 || mat_b.dim() == 3, "mat_b has to be 2 or 3d");
const bool a_is_2d = mat_a.dim() == 2;
const bool b_is_2d = mat_b.dim() == 2;
if (!a_is_2d || !b_is_2d) {
TORCH_CHECK(mat_a.size(-1) == mat_b.size(-2), "contraction dimension of mat_a and mat_b must match");
}
// check that the strides are valid, the fn will throw an error if not
check_valid_strides_and_return_transposed(mat_a);
check_valid_strides_and_return_transposed(mat_b);
TORCH_CHECK(offs.has_value() == (a_is_2d || b_is_2d), "Have to provide offsets if there is a 2d matrix, or no offset if both matrices are 3d");
if (offs.has_value()) {
TORCH_CHECK(offs->dim() == 1, "offs has to be 1D");
TORCH_CHECK(offs->dtype() == at::kInt, "Offsets have to be int32");
}
TORCH_CHECK(!bias.has_value(), "Bias not supported yet");
}
inline c10::ScalarType _resolve_grouped_mm_out_dtype(const Tensor& mat_a, const Tensor& mat_b,
std::optional<c10::ScalarType> out_dtype) {
const auto out_dtype_ = out_dtype.value_or(mat_a.scalar_type());
// TODO(future PR): enable float32 output dtype for bfloat16 and float16 inputs
TORCH_CHECK(out_dtype_ == mat_a.dtype(), "Grouped gemm output dtype must match `mat_a` dtype");
return out_dtype_;
}
inline void _grouped_mm_fallback(const Tensor& mat_a, const Tensor& mat_b,
const std::optional<at::Tensor>& offs,
const std::optional<at::Tensor>& bias,
std::optional<c10::ScalarType> out_dtype,
Tensor out) {
LOG(INFO) << "fallback path for `torch._grouped_mm`, performance may not be optimal";
const bool a_is_2d = mat_a.dim() == 2;
const bool b_is_2d = mat_b.dim() == 2;
if (a_is_2d && !b_is_2d) {
// 2d x 3d with offsets
int group_start_idx = 0;
auto offs_cpu = offs.value().cpu();
for (int group_idx = 0; group_idx < offs_cpu.size(0); group_idx++) {
int group_end_idx = offs_cpu[group_idx].item<int>();
auto mat_a_slice = mat_a.slice(0, group_start_idx, group_end_idx);
auto out_slice = out.slice(0, group_start_idx, group_end_idx);
at::mm_out(out_slice, mat_a_slice, mat_b[group_idx]);
group_start_idx = group_end_idx;
}
} else if (!a_is_2d && b_is_2d) {
// 3d x 2d with offsets
int group_start_idx = 0;
auto offs_cpu = offs.value().cpu();
for (int group_idx = 0; group_idx < offs_cpu.size(0); group_idx++) {
int group_end_idx = offs_cpu[group_idx].item<int>();
auto mat_b_slice = mat_b.slice(1, group_start_idx, group_end_idx);
auto out_slice = out.slice(1, group_start_idx, group_end_idx);
at::mm_out(out_slice, mat_a[group_idx], mat_b_slice);
group_start_idx = group_end_idx;
}
} else if (a_is_2d && b_is_2d) {
// 2d x 2d with offsets
int group_start_idx = 0;
auto offs_cpu = offs.value().cpu();
for (int group_idx = 0; group_idx < offs_cpu.size(0); group_idx++) {
int group_end_idx = offs_cpu[group_idx].item<int>();
auto mat_a_slice = mat_a.slice(1, group_start_idx, group_end_idx);
auto mat_b_slice = mat_b.slice(0, group_start_idx, group_end_idx);
auto out_slice = out[group_idx];
at::mm_out(out_slice, mat_a_slice, mat_b_slice);
group_start_idx = group_end_idx;
}
} else {
// 3d x 3d without offsets - regular bmm
at::bmm_out(out, mat_a, mat_b);
}
}
} // namespace at::native
#else
#error "This file should not be included when either TORCH_STABLE_ONLY or TORCH_TARGET_VERSION is defined."
#endif // !defined(TORCH_STABLE_ONLY) && !defined(TORCH_TARGET_VERSION)