[Kernel] Add per-tensor and per-token AZP epilogues (#5941)

Co-authored-by: Tyler Michael Smith <tyler@neuralmagic.com>
This commit is contained in:
Luka Govedič
2024-08-06 14:17:08 -04:00
committed by GitHub
parent 5c60c8c423
commit 8d59dbb000
11 changed files with 1175 additions and 153 deletions

View File

@@ -73,19 +73,63 @@ struct enable_sm89_to_sm90 : Kernel {
};
/*
* This class provides the common ScaleA and ScaleB descriptors for the
* ScaledEpilogue and ScaledEpilogueBias classes.
* This class provides the common load descriptors for the
* ScaledEpilogue[...] 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>>>;
template <typename T>
using ColOrScalarLoad =
cutlass::epilogue::threadblock::VisitorColOrScalarBroadcast<
OutputTileThreadMap, T, Stride<Int<1>, Int<0>, Int<0>>>;
using ScaleB = cutlass::epilogue::threadblock::VisitorRowOrScalarBroadcast<
OutputTileThreadMap, float, Stride<Int<0>, Int<1>, Int<0>>>;
template <typename T>
using RowOrScalarLoad =
cutlass::epilogue::threadblock::VisitorRowOrScalarBroadcast<
OutputTileThreadMap, T, Stride<Int<0>, Int<1>, Int<0>>>;
template <typename T>
using ColLoad = cutlass::epilogue::threadblock::VisitorColBroadcast<
OutputTileThreadMap, T, Stride<Int<1>, Int<0>, Int<0>>>;
template <typename T>
using RowLoad = cutlass::epilogue::threadblock::VisitorRowBroadcast<
OutputTileThreadMap, T, Stride<Int<0>, Int<1>, Int<0>>>;
template <typename T>
using RowOrZeroLoad =
cutlass::epilogue::threadblock::VisitorRowOrZeroBroadcast<
OutputTileThreadMap, T, Stride<Int<0>, Int<1>, Int<0>>>;
// This utility function constructs the arguments for the load descriptors
// from a tensor. It can handle both row and column, as well as row/column or
// scalar cases.
template <typename Descriptor, typename T>
static auto args_from_tensor(torch::Tensor const& tensor) {
using Arguments = typename Descriptor::Arguments;
auto* data_ptr = static_cast<T*>(tensor.data_ptr());
if constexpr (std::is_same_v<Descriptor, ColOrScalarLoad<T>> ||
std::is_same_v<Descriptor, RowOrScalarLoad<T>>) {
return Arguments{data_ptr, tensor.numel() != 1};
} else {
// it would technically work but no use case as data_ptr is never nullptr
static_assert(!std::is_same_v<Descriptor, RowOrZeroLoad<T>>);
return Arguments{data_ptr};
}
}
// This overload handles the case where there might not be a tensor, in which
// case a nullptr is passed and a constant (0) is used.
template <typename Descriptor, typename T>
static auto args_from_tensor(c10::optional<torch::Tensor> const& tensor) {
static_assert(std::is_same_v<Descriptor, RowOrZeroLoad<T>>);
using Arguments = typename Descriptor::Arguments;
auto* data_ptr = tensor ? static_cast<T*>(tensor->data_ptr()) : nullptr;
return Arguments{data_ptr};
}
};
/*
@@ -110,8 +154,8 @@ struct ScaledEpilogue
private:
using SUPER = ScaledEpilogueBase<ElementD, OutputTileThreadMap>;
using Accum = typename SUPER::Accum;
using ScaleA = typename SUPER::ScaleA;
using ScaleB = typename SUPER::ScaleB;
using ScaleA = typename SUPER::template ColOrScalarLoad<float>;
using ScaleB = typename SUPER::template RowOrScalarLoad<float>;
using Compute0 = cutlass::epilogue::threadblock::VisitorCompute<
cutlass::multiplies, float, float,
@@ -131,28 +175,32 @@ struct ScaledEpilogue
static ArgumentType prepare_args(torch::Tensor const& a_scales,
torch::Tensor const& b_scales) {
using ScaleAArgs = typename ScaleA::Arguments;
using ScaleBArgs = typename ScaleB::Arguments;
auto a_args = SUPER::template args_from_tensor<ScaleA, float>(a_scales);
auto b_args = SUPER::template args_from_tensor<ScaleB, float>(b_scales);
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;
typename EVTCompute0::Arguments evt0_args{b_args};
return ArgumentType{a_args, evt0_args};
}
};
/*
* This epilogue performs the same operation as ScaledEpilogue, but adds a bias.
* This bias can also be used in the per-tensor azp case, where the activation
* zero point (azp) is used to compute an azp correction term,
* which is folded into the bias.
*
* The bias tensor must be per-output channel.
* ScaleA and ScaleB can be per-tensor or per-token/per-channel.
*/
template <typename ElementD, typename OutputTileThreadMap>
struct ScaledEpilogueBias
: private ScaledEpilogueBase<ElementD, OutputTileThreadMap> {
private:
: protected ScaledEpilogueBase<ElementD, OutputTileThreadMap> {
protected:
using SUPER = ScaledEpilogueBase<ElementD, OutputTileThreadMap>;
using Accum = typename SUPER::Accum;
using ScaleA = typename SUPER::ScaleA;
using ScaleB = typename SUPER::ScaleB;
using ScaleA = typename SUPER::template ColOrScalarLoad<float>;
using ScaleB = typename SUPER::template RowOrScalarLoad<float>;
using Bias = typename SUPER::template RowLoad<ElementD>;
using Compute0 = cutlass::epilogue::threadblock::VisitorCompute<
cutlass::multiplies, float, float,
cutlass::FloatRoundStyle::round_to_nearest>;
@@ -164,30 +212,163 @@ struct ScaledEpilogueBias
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;
auto a_args = SUPER::template args_from_tensor<ScaleA, float>(a_scales);
auto b_args = SUPER::template args_from_tensor<ScaleB, float>(b_scales);
auto bias_args = SUPER::template args_from_tensor<Bias, ElementD>(bias);
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_args{b_args};
return ArgumentType{a_args, evt0_args, bias_args};
}
};
typename EVTCompute0::Arguments evt0_compute_args{b_args};
/*
* This epilogue directly supports per-tensor azp in int32 form.
* As opposed to the per-token epilogue below, this epilogue only has an azp_adj
* term, which should already be multiplied with the scalar azp.
* The azp_adj term is a 1D tensor of shape (1,n), computed as azp * J @ B.
*
* This epilogue also supports bias, which remains per-channel.
*/
template <typename ElementD, typename OutputTileThreadMap>
struct ScaledEpilogueBiasAzp
: protected ScaledEpilogueBase<ElementD, OutputTileThreadMap> {
private:
using SUPER = ScaledEpilogueBase<ElementD, OutputTileThreadMap>;
using Accum = typename SUPER::Accum;
using ScaleA = typename SUPER::template ColOrScalarLoad<float>;
using ScaleB = typename SUPER::template RowOrScalarLoad<float>;
using Bias = typename SUPER::template RowOrZeroLoad<ElementD>;
typename EVTCompute::Arguments evt_compute_args{a_args, evt0_compute_args,
bias_args};
return evt_compute_args;
// This is the full AZP term, azp * J @ B, shape (1,n)
using AzpWithAdj = typename SUPER::template RowLoad<int32_t>;
// Compute float(accum - azp_adj), both operands are int32_t
using ComputeAzp = cutlass::epilogue::threadblock::VisitorCompute<
cutlass::minus, float, int32_t,
cutlass::FloatRoundStyle::round_to_nearest>;
using EVTComputeAzp =
cutlass::epilogue::threadblock::Sm80EVT<ComputeAzp, Accum, AzpWithAdj>;
using ComputeScaleB = cutlass::epilogue::threadblock::VisitorCompute<
cutlass::multiplies, float, float,
cutlass::FloatRoundStyle::round_to_nearest>;
using EVTComputeScaleB =
cutlass::epilogue::threadblock::Sm80EVT<ComputeScaleB, ScaleB,
EVTComputeAzp>;
using ComputeScaleBiasA = cutlass::epilogue::threadblock::VisitorCompute<
cutlass::multiply_add, ElementD, float,
cutlass::FloatRoundStyle::round_to_nearest>;
public:
using EVTCompute =
cutlass::epilogue::threadblock::Sm80EVT<ComputeScaleBiasA, ScaleA,
EVTComputeScaleB, Bias>;
using ArgumentType = typename EVTCompute::Arguments;
static ArgumentType prepare_args(torch::Tensor const& a_scales,
torch::Tensor const& b_scales,
torch::Tensor const& azp_adj,
c10::optional<torch::Tensor> const& bias) {
auto a_args = SUPER::template args_from_tensor<ScaleA, float>(a_scales);
auto b_args = SUPER::template args_from_tensor<ScaleB, float>(b_scales);
auto bias_args = SUPER::template args_from_tensor<Bias, ElementD>(bias);
auto azp_adj_args =
SUPER::template args_from_tensor<AzpWithAdj, int32_t>(azp_adj);
typename EVTComputeAzp::Arguments evt_azp_args{{}, azp_adj_args};
typename EVTComputeScaleB::Arguments evt_scale_b_args{b_args, evt_azp_args};
return ArgumentType{a_args, evt_scale_b_args, bias_args};
}
};
/*
* This epilogue supports per-token azp by computing and applying
* the correction term using a rank-1 update. If the term were materialized,
* it would require O(m*n) space, and this way it only requires O(m+n) space.
* The azp term is a 1D tensor of shape (m,1), and represents the unscaled zero
* point for each row of A.
* The azp_adj term is a 1D tensor of shape (1,n), computed as J @ B.
*
* This epilogue also supports bias, which remains per-channel.
*/
template <typename ElementD, typename OutputTileThreadMap>
struct ScaledEpilogueBiasAzpToken
: protected ScaledEpilogueBase<ElementD, OutputTileThreadMap> {
private:
using SUPER = ScaledEpilogueBase<ElementD, OutputTileThreadMap>;
using Accum = typename SUPER::Accum;
using ScaleA = typename SUPER::template ColOrScalarLoad<float>;
using ScaleB = typename SUPER::template RowOrScalarLoad<float>;
using Bias = typename SUPER::template RowOrZeroLoad<ElementD>;
// Per-token azp term, shape (m,1)
using Azp = typename SUPER::template ColLoad<int32_t>;
// This is the AZP adjustment term, J @ B, shape (1,n)
using AzpAdj = typename SUPER::template RowLoad<int32_t>;
// Compute azp * azp_adj
using ComputeAzp = cutlass::epilogue::threadblock::VisitorCompute<
cutlass::multiplies, int32_t, int32_t,
cutlass::FloatRoundStyle::round_to_nearest>;
using EVTComputeAzp =
cutlass::epilogue::threadblock::Sm80EVT<ComputeAzp, Azp, AzpAdj>;
// Compute float(accum - azp*azp_adj), all operands are int32_t
using ComputeAcc = cutlass::epilogue::threadblock::VisitorCompute<
cutlass::minus, float, int32_t,
cutlass::FloatRoundStyle::round_to_nearest>;
using EVTComputeAcc =
cutlass::epilogue::threadblock::Sm80EVT<ComputeAcc, Accum, EVTComputeAzp>;
using ComputeScaleB = cutlass::epilogue::threadblock::VisitorCompute<
cutlass::multiplies, float, float,
cutlass::FloatRoundStyle::round_to_nearest>;
using EVTComputeScaleB =
cutlass::epilogue::threadblock::Sm80EVT<ComputeScaleB, ScaleB,
EVTComputeAcc>;
using ComputeScaleBiasA = cutlass::epilogue::threadblock::VisitorCompute<
cutlass::multiply_add, ElementD, float,
cutlass::FloatRoundStyle::round_to_nearest>;
public:
using EVTCompute =
cutlass::epilogue::threadblock::Sm80EVT<ComputeScaleBiasA, ScaleA,
EVTComputeScaleB, Bias>;
using ArgumentType = typename EVTCompute::Arguments;
static ArgumentType prepare_args(torch::Tensor const& a_scales,
torch::Tensor const& b_scales,
torch::Tensor const& azp_adj,
torch::Tensor const& azp,
c10::optional<torch::Tensor> const& bias) {
auto a_args = SUPER::template args_from_tensor<ScaleA, float>(a_scales);
auto b_args = SUPER::template args_from_tensor<ScaleB, float>(b_scales);
auto bias_args = SUPER::template args_from_tensor<Bias, ElementD>(bias);
auto azp_args = SUPER::template args_from_tensor<Azp, int32_t>(azp);
auto azp_adj_args =
SUPER::template args_from_tensor<AzpAdj, int32_t>(azp_adj);
typename EVTComputeAzp::Arguments evt_azp_args{azp_args, azp_adj_args};
typename EVTComputeAcc::Arguments evt_acc_args{{}, evt_azp_args};
typename EVTComputeScaleB::Arguments evt_scale_b_args{b_args, evt_acc_args};
return ArgumentType{a_args, evt_scale_b_args, bias_args};
}
};