sglang_v0.5.2/flashinfer_0.3.1/csrc/bmm_fp8.cu

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/*
* Copyright (c) 2024 by FlashInfer team.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include <driver_types.h>
#include <flashinfer/gemm/bmm_fp8.cuh>
#include "pytorch_extension_utils.h"
void bmm_fp8(at::Tensor A, at::Tensor B, at::Tensor D, at::Tensor A_scale, at::Tensor B_scale,
at::Tensor workspace_buffer, int64_t cublas_handle) {
TORCH_CHECK(A.is_cuda(), "A must be a CUDA tensor");
TORCH_CHECK(B.is_cuda(), "B must be a CUDA tensor");
TORCH_CHECK(D.is_cuda(), "D must be a CUDA tensor");
TORCH_CHECK(A.dim() == 3, "Expected 3D tensor for A");
TORCH_CHECK(B.dim() == 3, "Expected 3D tensor for B");
TORCH_CHECK(D.dim() == 3, "Expected 3D tensor for D");
TORCH_CHECK(A.size(0) == B.size(0) && A.size(0) == D.size(0), "Batch sizes must match");
TORCH_CHECK(A.size(2) == B.size(1), "Incompatible matrix sizes");
TORCH_CHECK(A.size(1) == D.size(1) && B.size(2) == D.size(2),
"Result tensor has incorrect shape");
// PyTorch is row major by default. cuBLASLt is column major by default.
// We need row major D as expected.
// A ^ T * B = D, so D ^ T = B ^ T * A
DISPATCH_PYTORCH_DTYPE_TO_CTYPE_FP8(B.scalar_type(), b_type, [&] {
return DISPATCH_PYTORCH_DTYPE_TO_CTYPE_FP8(A.scalar_type(), a_type, [&] {
return DISPATCH_PYTORCH_DTYPE_TO_CTYPE_FP16(D.scalar_type(), d_type, [&] {
auto batch_size = A.size(0);
auto m = A.size(1);
auto k = A.size(2);
auto n = B.size(2);
auto lt_handle = reinterpret_cast<cublasLtHandle_t>(cublas_handle);
const c10::cuda::OptionalCUDAGuard device_guard(A.device());
auto stream = at::cuda::getCurrentCUDAStream();
auto status = flashinfer::bmm_fp8::bmm_fp8_internal_cublaslt(
workspace_buffer.data_ptr(), workspace_buffer.numel(),
static_cast<b_type*>(B.data_ptr()), static_cast<a_type*>(A.data_ptr()),
static_cast<d_type*>(D.data_ptr()), batch_size, n, m, k,
static_cast<float*>(B_scale.data_ptr()), static_cast<float*>(A_scale.data_ptr()),
lt_handle, stream);
TORCH_CHECK(status == CUBLAS_STATUS_SUCCESS,
"bmm_fp8_internal_cublaslt failed: ", cublasGetStatusString(status));
return true;
});
});
});
}