vllm/csrc/quantization/cutlass_w8a8/scaled_mm_c2x.cuh
2024-08-05 15:13:43 -04:00

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#pragma once
#include <stddef.h>
#include <torch/all.h>
#include <ATen/cuda/CUDAContext.h>
// clang-format will break include orders
// clang-format off
#include "cute/tensor.hpp"
#include "cute/atom/mma_atom.hpp"
#include "cutlass/numeric_types.h"
#include "cutlass/cutlass.h"
#include "cutlass/gemm_coord.h"
#include "cutlass/arch/mma_sm75.h"
#include "cutlass/arch/arch.h"
#include "cutlass/arch/mma.h"
#include "cutlass/gemm/device/gemm.h"
#include "cutlass/gemm/device/gemm_universal_adapter.h"
#include "cutlass/epilogue/threadblock/fusion/visitors.hpp"
#include "cutlass/gemm/kernel/default_gemm_universal_with_visitor.h"
#include "broadcast_load_epilogue_c2x.hpp"
#include "common.hpp"
// clang-format on
using namespace cute;
/*
Epilogue functions can be defined to post-process the output before it is
written to GPU memory.
Epilogues must contain a public type named EVTCompute of type Sm80EVT,
as well as a static prepare_args function that constructs an
EVTCompute::Arguments struct.
*/
namespace vllm {
// Wrappers for the GEMM kernel that is used to guard against compilation on
// architectures that will never use the kernel. The purpose of this is to
// reduce the size of the compiled binary.
// __CUDA_ARCH__ is not defined in host code, so this lets us smuggle the ifdef
// into code that will be executed on the device where it is defined.
template <typename Kernel>
struct enable_sm75_to_sm80 : Kernel {
template <typename... Args>
CUTLASS_DEVICE static void invoke(Args&&... args) {
#if defined __CUDA_ARCH__ && __CUDA_ARCH__ >= 750 && __CUDA_ARCH__ < 800
Kernel::invoke(std::forward<Args>(args)...);
#endif
}
};
template <typename Kernel>
struct enable_sm80_to_sm89 : Kernel {
template <typename... Args>
CUTLASS_DEVICE static void invoke(Args&&... args) {
#if defined __CUDA_ARCH__ && __CUDA_ARCH__ >= 800 && __CUDA_ARCH__ < 890
Kernel::invoke(std::forward<Args>(args)...);
#endif
}
};
template <typename Kernel>
struct enable_sm89_to_sm90 : Kernel {
template <typename... Args>
CUTLASS_DEVICE static void invoke(Args&&... args) {
#if defined __CUDA_ARCH__ && __CUDA_ARCH__ >= 890 && __CUDA_ARCH__ < 900
Kernel::invoke(std::forward<Args>(args)...);
#endif
}
};
/*
* This class provides the common ScaleA and ScaleB descriptors for the
* ScaledEpilogue and ScaledEpilogueBias classes.
*/
template <typename ElementD, typename OutputTileThreadMap>
struct ScaledEpilogueBase {
protected:
using Accum = cutlass::epilogue::threadblock::VisitorAccFetch;
using ScaleA = cutlass::epilogue::threadblock::VisitorColOrScalarBroadcast<
OutputTileThreadMap, float, Stride<Int<1>, Int<0>, Int<0>>>;
using ScaleB = cutlass::epilogue::threadblock::VisitorRowOrScalarBroadcast<
OutputTileThreadMap, float, Stride<Int<0>, Int<1>, Int<0>>>;
};
/*
This epilogue function defines a quantized GEMM operation similar to
torch._scaled_mm.
A and B may be both either int8 or fp8_e4m3. A can be quantized per-tensor or
per-row. B can be quantized per-tensor or per-column.
Any combination of per-tensor and per-row or column is supported.
A and B must have symmetric quantization (zero point == 0).
So the GEMM operation is D = (a_scales * A) (b_scales * B), where the
scales are applied elementwise with numpy-style broadcasting.
ScaleA and ScaleB define the epilogue functions that apply the scales for
the A and B operands respectively. These scales may be either per-tensor or
per row or column.
*/
template <typename ElementD, typename OutputTileThreadMap>
struct ScaledEpilogue
: private ScaledEpilogueBase<ElementD, OutputTileThreadMap> {
private:
using SUPER = ScaledEpilogueBase<ElementD, OutputTileThreadMap>;
using Accum = typename SUPER::Accum;
using ScaleA = typename SUPER::ScaleA;
using ScaleB = typename SUPER::ScaleB;
using Compute0 = cutlass::epilogue::threadblock::VisitorCompute<
cutlass::multiplies, float, float,
cutlass::FloatRoundStyle::round_to_nearest>;
using EVTCompute0 =
cutlass::epilogue::threadblock::Sm80EVT<Compute0, ScaleB, Accum>;
using Compute1 = cutlass::epilogue::threadblock::VisitorCompute<
cutlass::multiplies, ElementD, float,
cutlass::FloatRoundStyle::round_to_nearest>;
public:
using EVTCompute =
cutlass::epilogue::threadblock::Sm80EVT<Compute1, ScaleA, EVTCompute0>;
using ArgumentType = typename EVTCompute::Arguments;
static ArgumentType prepare_args(torch::Tensor const& a_scales,
torch::Tensor const& b_scales) {
using ScaleAArgs = typename ScaleA::Arguments;
using ScaleBArgs = typename ScaleB::Arguments;
ScaleBArgs b_args{b_scales.data_ptr<float>(), b_scales.numel() != 1, {}};
ScaleAArgs a_args{a_scales.data_ptr<float>(), a_scales.numel() != 1, {}};
typename EVTCompute0::Arguments evt0_compute_args{b_args};
typename EVTCompute::Arguments evt_compute_args{a_args, evt0_compute_args};
return evt_compute_args;
}
};
template <typename ElementD, typename OutputTileThreadMap>
struct ScaledEpilogueBias
: private ScaledEpilogueBase<ElementD, OutputTileThreadMap> {
private:
using SUPER = ScaledEpilogueBase<ElementD, OutputTileThreadMap>;
using Accum = typename SUPER::Accum;
using ScaleA = typename SUPER::ScaleA;
using ScaleB = typename SUPER::ScaleB;
using Compute0 = cutlass::epilogue::threadblock::VisitorCompute<
cutlass::multiplies, float, float,
cutlass::FloatRoundStyle::round_to_nearest>;
using EVTCompute0 =
cutlass::epilogue::threadblock::Sm80EVT<Compute0, ScaleB, Accum>;
using Compute1 = cutlass::epilogue::threadblock::VisitorCompute<
cutlass::multiply_add, ElementD, float,
cutlass::FloatRoundStyle::round_to_nearest>;
using Bias = cutlass::epilogue::threadblock::VisitorRowBroadcast<
OutputTileThreadMap, ElementD, Stride<Int<0>, Int<1>, Int<0>>>;
public:
using EVTCompute = cutlass::epilogue::threadblock::Sm80EVT<Compute1, ScaleA,
EVTCompute0, Bias>;
using ArgumentType = typename EVTCompute::Arguments;
static ArgumentType prepare_args(torch::Tensor const& a_scales,
torch::Tensor const& b_scales,
torch::Tensor const& bias) {
using ScaleAArgs = typename ScaleA::Arguments;
using ScaleBArgs = typename ScaleB::Arguments;
using BiasArgs = typename Bias::Arguments;
ScaleBArgs b_args{b_scales.data_ptr<float>(), b_scales.numel() != 1, {}};
ScaleAArgs a_args{a_scales.data_ptr<float>(), a_scales.numel() != 1, {}};
BiasArgs bias_args{static_cast<ElementD*>(bias.data_ptr()), {}};
typename EVTCompute0::Arguments evt0_compute_args{b_args};
typename EVTCompute::Arguments evt_compute_args{a_args, evt0_compute_args,
bias_args};
return evt_compute_args;
}
};
template <typename Arch, template <typename> typename ArchGuard,
typename ElementAB_, typename ElementD_,
template <typename, typename> typename Epilogue_, typename TileShape,
typename WarpShape, typename InstructionShape, int32_t MainLoopStages,
typename FP8MathOperator = cutlass::arch::OpMultiplyAdd>
struct cutlass_2x_gemm {
using ElementAB = ElementAB_;
using ElementD = ElementD_;
using ElementAcc =
typename std::conditional<std::is_same_v<ElementAB, int8_t>, int32_t,
float>::type;
using Operator =
typename std::conditional<std::is_same_v<ElementAB, int8_t>,
cutlass::arch::OpMultiplyAddSaturate,
FP8MathOperator>::type;
using OutputTileThreadMap =
cutlass::epilogue::threadblock::OutputTileThreadLayout<
TileShape, WarpShape, float, 4, 1 /* epilogue stages */
>;
using Epilogue = Epilogue_<ElementD, OutputTileThreadMap>;
using EVTCompute = typename Epilogue::EVTCompute;
using D = cutlass::epilogue::threadblock::VisitorAuxStore<
OutputTileThreadMap, ElementD, cutlass::FloatRoundStyle::round_to_nearest,
Stride<int64_t, Int<1>, Int<0>>>;
using EVTD = cutlass::epilogue::threadblock::Sm80EVT<D, EVTCompute>;
// clang-format off
using RowMajor = typename cutlass::layout::RowMajor;
using ColumnMajor = typename cutlass::layout::ColumnMajor;
using KernelType =
ArchGuard<typename cutlass::gemm::kernel::DefaultGemmWithVisitor<
ElementAB, RowMajor, cutlass::ComplexTransform::kNone, 16,
ElementAB, ColumnMajor, cutlass::ComplexTransform::kNone, 16,
float, cutlass::layout::RowMajor, 4,
ElementAcc, float, cutlass::arch::OpClassTensorOp,
Arch,
TileShape, WarpShape, InstructionShape,
EVTD,
cutlass::gemm::threadblock::ThreadblockSwizzleStreamK,
MainLoopStages, Operator,
1 /* epilogue stages */
>::GemmKernel>;
// clang-format on
using Op = cutlass::gemm::device::GemmUniversalAdapter<KernelType>;
};
template <typename Gemm, typename... EpilogueArgs>
inline void cutlass_gemm_caller(torch::Tensor& out, torch::Tensor const& a,
torch::Tensor const& b,
EpilogueArgs&&... epilogue_params) {
using ElementAB = typename Gemm::ElementAB;
using ElementD = typename Gemm::ElementD;
int32_t m = a.size(0);
int32_t n = b.size(1);
int32_t k = a.size(1);
cutlass::gemm::GemmCoord problem_size{m, n, k};
int64_t lda = a.stride(0);
int64_t ldb = b.stride(1);
int64_t ldc = out.stride(0);
using StrideC = Stride<int64_t, Int<1>, Int<0>>;
StrideC c_stride{ldc, Int<1>{}, Int<0>{}};
auto a_ptr = static_cast<ElementAB const*>(a.data_ptr());
auto b_ptr = static_cast<ElementAB const*>(b.data_ptr());
auto c_ptr = static_cast<ElementD*>(out.data_ptr());
typename Gemm::D::Arguments d_args{c_ptr, c_stride};
using Epilogue = typename Gemm::Epilogue;
auto evt_args =
Epilogue::prepare_args(std::forward<EpilogueArgs>(epilogue_params)...);
typename Gemm::EVTD::Arguments epilogue_args{
evt_args,
d_args,
};
typename Gemm::Op::Arguments args{
cutlass::gemm::GemmUniversalMode::kGemmSplitKParallel, // universal mode
problem_size, // problem size
1, // batch count
epilogue_args,
a_ptr,
b_ptr,
nullptr,
nullptr,
0,
0,
0,
0,
lda,
ldb,
ldc,
ldc};
// Launch the CUTLASS GEMM kernel.
typename Gemm::Op gemm_op;
size_t workspace_size = gemm_op.get_workspace_size(args);
auto const workspace_options =
torch::TensorOptions().dtype(torch::kUInt8).device(a.device());
auto workspace = torch::empty(workspace_size, workspace_options);
auto stream = at::cuda::getCurrentCUDAStream(a.get_device());
CUTLASS_CHECK(gemm_op.can_implement(args));
cutlass::Status status = gemm_op(args, workspace.data_ptr(), stream);
CUTLASS_CHECK(status);
}
template <typename Gemm, typename FallbackGemm, typename... EpilogueArgs>
inline void fallback_cutlass_gemm_caller(torch::Tensor& out,
torch::Tensor const& a,
torch::Tensor const& b,
EpilogueArgs&&... args) {
// In some cases, the GPU isn't able to accommodate the
// shared memory requirements of the Gemm. In such cases, use
// the FallbackGemm instead.
static const int max_shared_mem_per_block_opt_in =
get_cuda_max_shared_memory_per_block_opt_in(0);
size_t const gemm_shared_mem_size =
sizeof(typename Gemm::KernelType::SharedStorage);
size_t const fallback_gemm_shared_mem_size =
sizeof(typename FallbackGemm::KernelType::SharedStorage);
if (gemm_shared_mem_size <= max_shared_mem_per_block_opt_in) {
return cutlass_gemm_caller<Gemm>(out, a, b,
std::forward<EpilogueArgs>(args)...);
} else {
TORCH_CHECK(fallback_gemm_shared_mem_size <=
max_shared_mem_per_block_opt_in);
return cutlass_gemm_caller<FallbackGemm>(
out, a, b, std::forward<EpilogueArgs>(args)...);
}
}
} // namespace vllm