Add first kernel of normalization splitK

include/ck/tensor_operation/gpu/device/impl/device_normalization_splitk_impl.hpp

+// SPDX-License-Identifier: MIT
+// Copyright (c) 2018-2022, Advanced Micro Devices, Inc. All rights reserved.
+
+#pragma once
+
+#include <iostream>
+#include <sstream>
+
+#include "ck/utility/reduction_operator.hpp"
+#include "ck/tensor_operation/gpu/device/matrix_padder.hpp"
+#include "ck/tensor_operation/gpu/device/device_normalization.hpp"
+#include "ck/tensor_operation/gpu/device/device_reduce.hpp"
+#include "ck/tensor_operation/gpu/device/impl/device_reduce_common.hpp"
+#include "ck/tensor_operation/gpu/grid/normalization/gridwise_normalization_splitk_1st.hpp"
+#include "ck/tensor_operation/gpu/grid/gridwise_set_buffer_value.hpp"
+#include "ck/host_utility/device_prop.hpp"
+#include "ck/host_utility/kernel_launch.hpp"
+
+namespace ck {
+template <typename GridwiseWelford1,
+          typename XDataType,
+          typename MeanVarDataType,
+          typename ComputeDataType,
+          typename XGridDesc_M_K,
+          typename MeanVarGridDesc_M_KBlock>
+__global__ void
+kernel_normalizationSplitK1st(const XGridDesc_M_K x_grid_desc_m_k,
+                              const MeanVarGridDesc_M_KBlock mean_var_grid_desc_m_kblock,
+                              index_t num_k_block_tile_iteration,
+                              const XDataType* const __restrict__ p_x_global,
+                              MeanVarDataType* const __restrict__ p_welford_mean,
+                              MeanVarDataType* const __restrict__ p_welford_variance,
+                              int32_t* const __restrict__ p_welford_count)
+{
+    GridwiseWelford1::Run(x_grid_desc_m_k,
+                          mean_var_grid_desc_m_kblock,
+                          num_k_block_tile_iteration,
+                          p_x_global,
+                          p_welford_mean,
+                          p_welford_variance,
+                          p_welford_count);
+};
+} // namespace ck
+
+namespace ck {
+namespace tensor_operation {
+namespace device {
+
+// Y = Normalization(X, Beta, Gamma)
+// M: Invarient length
+// K: Reduce length (Calculate mean and variance along K dimension)
+// eg. Length = [N, C, H, W], reduce dim = [C, H, W]
+// Then, M = N, K = C * H * W
+template <typename XDataType,
+          typename GammaDataType,
+          typename BetaDataType,
+          typename ComputeDataType,
+          typename YDataType,
+          typename YElementwiseOperation,
+          index_t Rank,
+          index_t NumReduceDim,
+          index_t BlockSize,
+          index_t MThreadClusterSize,
+          index_t KThreadClusterSize,
+          index_t MThreadSliceSize,
+          index_t KThreadSliceSize,
+          index_t XYSrcVectorDim,
+          index_t XSrcVectorSize,
+          index_t GammaSrcVectorDim,
+          index_t GammaSrcVectorSize,
+          index_t BetaSrcVectorDim,
+          index_t BetaSrcVectorSize,
+          index_t YDstVectorSize>
+struct DeviceNormalizationSplitKImpl : public DeviceNormalization<XDataType,
+                                                                  GammaDataType,
+                                                                  BetaDataType,
+                                                                  ComputeDataType,
+                                                                  YDataType,
+                                                                  YElementwiseOperation,
+                                                                  Rank,
+                                                                  NumReduceDim>
+{
+    using MeanVarDataType = ComputeDataType;
+
+    static_assert(BlockSize == MThreadClusterSize * KThreadClusterSize);
+    static_assert(
+        ((GammaSrcVectorDim == 0 && MThreadSliceSize % GammaSrcVectorSize == 0) ||
+         (GammaSrcVectorDim == 1 && KThreadSliceSize % GammaSrcVectorSize == 0)),
+        "Invalid thread slice sizes and/or gamma vector sizes configuration, please check!");
+
+    static_assert(
+        ((BetaSrcVectorDim == 0 && MThreadSliceSize % BetaSrcVectorSize == 0) ||
+         (BetaSrcVectorDim == 1 && KThreadSliceSize % BetaSrcVectorSize == 0)),
+        "Invalid thread slice sizes and/or beta vector sizes configuration, please check!");
+
+    using PassThrough = tensor_operation::element_wise::PassThrough;
+
+    static constexpr auto I0 = Number<0>{};
+    static constexpr auto I1 = Number<1>{};
+
+    static constexpr index_t M_BlockTileSize = MThreadClusterSize * MThreadSliceSize;
+    static constexpr index_t K_BlockTileSize = KThreadClusterSize * KThreadSliceSize;
+
+    static auto MakeSrc2dDescriptor(const std::vector<index_t>& inLengths,
+                                    const std::vector<index_t>& inStrides,
+                                    int kBlockSize,
+                                    int numBlockTileIteration)
+    {
+        constexpr index_t NumInvariantDim  = Rank - NumReduceDim;
+        static constexpr index_t numSrcDim = Rank;
+        static constexpr bool reduceAllDim = (NumInvariantDim == 0);
+
+        const auto tupleSrcLengths = make_tuple_from_array(inLengths, Number<numSrcDim>{});
+        const auto tupleSrcStrides = make_tuple_from_array(inStrides, Number<numSrcDim>{});
+
+        const auto inDesc = make_naive_tensor_descriptor(tupleSrcLengths, tupleSrcStrides);
+
+        const auto in_grid_desc_m_k = [&]() {
+            if constexpr(reduceAllDim)
+            {
+                const auto one_dim_inDesc = transform_tensor_descriptor(
+                    inDesc,
+                    make_tuple(make_merge_transform(tupleSrcLengths)),
+                    make_tuple(typename arithmetic_sequence_gen<0, numSrcDim, 1>::type{}),
+                    make_tuple(Sequence<0>{}));
+
+                return transform_tensor_descriptor(one_dim_inDesc,
+                                                   make_tuple(make_unmerge_transform(make_tuple(
+                                                       1, one_dim_inDesc.GetLength(Number<0>{})))),
+                                                   make_tuple(Sequence<0>{}),
+                                                   make_tuple(Sequence<0, 1>{}));
+            }
+            else
+            {
+                using InvariantDims = typename arithmetic_sequence_gen<0, NumInvariantDim, 1>::type;
+                using ReduceDims = typename arithmetic_sequence_gen<NumInvariantDim, Rank, 1>::type;
+
+                const auto reduceDimLengths =
+                    make_tuple_from_array_and_index_seq(inLengths, ReduceDims{});
+                const auto invariantDimLengths =
+                    make_tuple_from_array_and_index_seq(inLengths, InvariantDims{});
+
+                return transform_tensor_descriptor(
+                    inDesc,
+                    make_tuple(make_merge_transform(invariantDimLengths),
+                               make_merge_transform(reduceDimLengths)),
+                    make_tuple(InvariantDims{}, ReduceDims{}),
+                    make_tuple(Sequence<0>{}, Sequence<1>{}));
+            }
+        }();
+
+        const auto invariantLength = in_grid_desc_m_k.GetLength(Number<0>{});
+        const auto reduceLength    = in_grid_desc_m_k.GetLength(Number<1>{});
+
+        const int reduceSizePerBlock = K_BlockTileSize * numBlockTileIteration;
+        const auto inPad_M =
+            math::integer_least_multiple(invariantLength, M_BlockTileSize) - invariantLength;
+        const auto inPad_K = reduceSizePerBlock * kBlockSize - reduceLength;
+
+        auto in_grid_desc_m_k_padded = transform_tensor_descriptor(
+            in_grid_desc_m_k,
+            make_tuple(make_right_pad_transform(invariantLength, inPad_M),
+                       make_right_pad_transform(reduceLength, inPad_K)),
+            make_tuple(Sequence<0>{}, Sequence<1>{}),
+            make_tuple(Sequence<0>{}, Sequence<1>{}));
+
+        return (in_grid_desc_m_k_padded);
+    };
+
+    template <typename DoPads, index_t MPerTile, index_t KPerTile>
+    static auto MakeMeanVarDescriptor_M_K(index_t M, index_t K)
+    {
+        const auto grid_desc_m_n =
+            make_naive_tensor_descriptor(make_tuple(M, K), make_tuple(K, I1));
+        return PadTensorDescriptor(grid_desc_m_n, make_tuple(MPerTile, KPerTile), DoPads{});
+    }
+
+    template <typename DoPads, index_t MPerTile, index_t KPerTile>
+    static auto MakeCountDescriptor_M_K(index_t M, index_t K)
+    {
+        const auto grid_desc_m_n =
+            make_naive_tensor_descriptor(make_tuple(M, K), make_tuple(I0, I1));
+        return PadTensorDescriptor(grid_desc_m_n, make_tuple(MPerTile, KPerTile), DoPads{});
+    }
+
+    using SrcGridDesc_M_K = decltype(MakeSrc2dDescriptor({1}, {1}, 1, 1));
+    using Welford1MeanVarGridDesc_M_KBlock =
+        decltype(MakeMeanVarDescriptor_M_K<Sequence<true, false>, 1, 1>(1, 1));
+
+    using GridwiseWelford1 = GridwiseNormalizationSplitK1st<XDataType,
+                                                            ComputeDataType,
+                                                            MeanVarDataType,
+                                                            SrcGridDesc_M_K,
+                                                            Welford1MeanVarGridDesc_M_KBlock,
+                                                            BlockSize,
+                                                            MThreadClusterSize,
+                                                            KThreadClusterSize,
+                                                            MThreadSliceSize,
+                                                            KThreadSliceSize,
+                                                            XYSrcVectorDim,
+                                                            XSrcVectorSize>;
+
+    struct Argument : public BaseArgument
+    {
+        Argument(const std::vector<index_t> lengths,
+                 const std::vector<index_t> xStrides,
+                 const std::vector<index_t> gammaStrides,
+                 const std::vector<index_t> betaStrides,
+                 const std::vector<index_t> yStrides,
+                 const std::vector<index_t> reduceDims,
+                 YElementwiseOperation y_elementwise_op,
+                 double epsilon,
+                 const XDataType* p_x,
+                 const GammaDataType* p_gamma,
+                 const BetaDataType* p_beta,
+                 YDataType* p_y)
+            : p_x_(p_x),
+              p_gamma_(p_gamma),
+              p_beta_(p_beta),
+              p_y_(p_y),
+              p_workspace_mean_{nullptr},
+              p_workspace_var_{nullptr},
+              p_workspace_count_{nullptr},
+              y_elementwise_op_(y_elementwise_op)
+        {
+            epsilon_ = static_cast<ComputeDataType>(epsilon);
+
+            Lengths_      = shuffle_tensor_dimensions<Rank, NumReduceDim>(lengths, reduceDims);
+            xStrides_     = shuffle_tensor_dimensions<Rank, NumReduceDim>(xStrides, reduceDims);
+            yStrides_     = shuffle_tensor_dimensions<Rank, NumReduceDim>(yStrides, reduceDims);
+            gammaStrides_ = shuffle_tensor_dimensions<Rank, NumReduceDim>(gammaStrides, reduceDims);
+            betaStrides_  = shuffle_tensor_dimensions<Rank, NumReduceDim>(betaStrides, reduceDims);
+
+            std::tie(MRaw_, KRaw_) = get_2d_lengths<Rank, NumReduceDim>(Lengths_);
+
+            numBlockTileIteration_ = 1;
+            while(true)
+            {
+                int testKGridSize_ =
+                    math::integer_divide_ceil(KRaw_, K_BlockTileSize * numBlockTileIteration_);
+
+                // we want the testKGridSize_ be not more than 128
+                if(testKGridSize_ <= 128)
+                    break;
+
+                ++numBlockTileIteration_;
+            };
+
+            kGridSize_ = math::integer_divide_ceil(KRaw_, K_BlockTileSize * numBlockTileIteration_);
+
+            gridSize_ = math::integer_divide_ceil(MRaw_, M_BlockTileSize) * kGridSize_;
+
+            x_grid_desc_m_k_ =
+                MakeSrc2dDescriptor(Lengths_, xStrides_, kGridSize_, numBlockTileIteration_);
+            gamma_grid_desc_m_k_ =
+                MakeSrc2dDescriptor(Lengths_, gammaStrides_, kGridSize_, numBlockTileIteration_);
+            beta_grid_desc_m_k_ =
+                MakeSrc2dDescriptor(Lengths_, betaStrides_, kGridSize_, numBlockTileIteration_);
+            y_grid_desc_m_k_ =
+                MakeSrc2dDescriptor(Lengths_, yStrides_, kGridSize_, numBlockTileIteration_);
+
+            // We don't need to pad in K dimension for Welford1. Set KPerTile 1.
+            mean_var_grid_desc_m_kblock_ =
+                MakeMeanVarDescriptor_M_K<Sequence<true, false>, M_BlockTileSize, 1>(MRaw_,
+                                                                                     kGridSize_);
+        }
+
+        ComputeDataType epsilon_;
+
+        const XDataType* p_x_;
+        const GammaDataType* p_gamma_;
+        const BetaDataType* p_beta_;
+        YDataType* p_y_;
+        void* p_workspace_mean_;
+        void* p_workspace_var_;
+        void* p_workspace_count_;
+
+        std::vector<index_t> Lengths_;
+        std::vector<index_t> xStrides_;
+        std::vector<index_t> gammaStrides_;
+        std::vector<index_t> betaStrides_;
+        std::vector<index_t> yStrides_;
+
+        YElementwiseOperation y_elementwise_op_;
+
+        int kGridSize_;
+        int numBlockTileIteration_;
+        size_t gridSize_;
+
+        SrcGridDesc_M_K x_grid_desc_m_k_;
+        SrcGridDesc_M_K gamma_grid_desc_m_k_;
+        SrcGridDesc_M_K beta_grid_desc_m_k_;
+        SrcGridDesc_M_K y_grid_desc_m_k_;
+
+        Welford1MeanVarGridDesc_M_KBlock mean_var_grid_desc_m_kblock_;
+
+        index_t MRaw_; // invarient length
+        index_t KRaw_; // reduce length
+    };
+
+    struct Invoker : public BaseInvoker
+    {
+        float Run(const Argument& arg, const StreamConfig& stream_config = StreamConfig{})
+        {
+            if(arg.p_workspace_mean_ == nullptr || arg.p_workspace_var_ == nullptr ||
+               arg.p_workspace_count_ == nullptr)
+                throw std::runtime_error("wrong! WorkSpace pointer has not been set");
+
+            auto kernel1 = kernel_normalizationSplitK1st<GridwiseWelford1,
+                                                         XDataType,
+                                                         MeanVarDataType,
+                                                         ComputeDataType,
+                                                         SrcGridDesc_M_K,
+                                                         Welford1MeanVarGridDesc_M_KBlock>;
+
+            float avg_time = 0;
+            avg_time += launch_and_time_kernel(stream_config,
+                                               kernel1,
+                                               dim3(arg.gridSize_),
+                                               dim3(BlockSize),
+                                               0,
+                                               arg.x_grid_desc_m_k_,
+                                               arg.mean_var_grid_desc_m_kblock_,
+                                               arg.numBlockTileIteration_,
+                                               arg.p_x_,
+                                               static_cast<MeanVarDataType*>(arg.p_workspace_mean_),
+                                               static_cast<MeanVarDataType*>(arg.p_workspace_var_),
+                                               static_cast<int32_t*>(arg.p_workspace_count_));
+
+            // TODO - welford2 + elementwise
+
+            return (avg_time);
+        };
+
+        float Run(const BaseArgument* p_arg,
+                  const StreamConfig& stream_config = StreamConfig{}) override
+        {
+            return Run(*dynamic_cast<const Argument*>(p_arg), stream_config);
+        };
+    };
+
+    size_t GetWorkSpaceSize(const BaseArgument* pArg) const override
+    {
+        const Argument* pArg_ = dynamic_cast<const Argument*>(pArg);
+
+        size_t workspace_size = 0;
+
+        int welford_size = pArg_->MRaw_ * pArg_->kGridSize_;
+
+        // workspace for welford intermediate mean
+        workspace_size += welford_size * sizeof(MeanVarDataType) + 64;
+
+        // workspace for welford intermediate variance
+        workspace_size += welford_size * sizeof(MeanVarDataType) + 64;
+
+        // workspace for welford intermediate count
+        workspace_size += pArg_->kGridSize_ * sizeof(int32_t) + 64;
+
+        return (workspace_size);
+    };
+
+    void SetWorkSpacePointer(BaseArgument* pArg, void* p_workspace) const override
+    {
+        Argument* pArg_ = dynamic_cast<Argument*>(pArg);
+
+        pArg_->p_workspace_ = p_workspace;
+
+        int welford_size = pArg_->MRaw_ * pArg_->kGridSize_;
+
+        // setup buffer used for intermediate welford mean
+        pArg_->p_workspace_mean_ = static_cast<char*>(pArg_->p_workspace_);
+
+        index_t mean_space_sz = welford_size * sizeof(MeanVarDataType);
+        mean_space_sz         = math::integer_least_multiple(mean_space_sz, 64);
+
+        // setup buffer used for intermediate welford varirance
+        pArg_->p_workspace_var_ = reinterpret_cast<char*>(pArg_->p_workspace_mean_) + mean_space_sz;
+
+        index_t variance_space_sz = welford_size * sizeof(MeanVarDataType);
+        variance_space_sz         = math::integer_least_multiple(variance_space_sz, 64);
+
+        // setup buffer used for intermediate welford count
+        pArg_->p_workspace_count_ =
+            reinterpret_cast<char*>(pArg_->p_workspace_var_) + variance_space_sz;
+    };
+
+    bool IsSupportedArgument(const BaseArgument* p_arg) override
+    {
+        const Argument* p_arg_ = dynamic_cast<const Argument*>(p_arg);
+
+        constexpr index_t NumInvariantDim = Rank - NumReduceDim;
+
+        if constexpr(XYSrcVectorDim == 0)
+        {
+            if constexpr(NumInvariantDim == 0)
+            {
+                return false;
+            }
+            else
+            {
+                if(p_arg_->xStrides_[NumInvariantDim - 1] != 1)
+                    return false;
+
+                if(p_arg_->invariant_lowest_length % XSrcVectorSize != 0)
+                    return false;
+            };
+        }
+        else
+        {
+            if(p_arg_->xStrides_[Rank - 1] != 1)
+                return false;
+
+            if(p_arg_->Lengths_[Rank - 1] % XSrcVectorSize != 0)
+                return false;
+        };
+
+        if(p_arg_->Lengths_[Rank - 1] % YDstVectorSize != 0)
+        {
+            return false;
+        }
+
+        // if fastest dim is not reduced
+        if constexpr(GammaSrcVectorDim == 0)
+        {
+            if(p_arg_->gammaStrides_[NumInvariantDim - 1] != 1)
+                return (false);
+
+            if(p_arg_->Lengths_[Rank - 1] % GammaSrcVectorSize != 0)
+                return (false);
+        }
+        else // if fastest dim is reduced
+        {
+            if(p_arg_->gammaStrides_[Rank - 1] != 1)
+                return (false);
+
+            if(p_arg_->Lengths_[Rank - 1] % GammaSrcVectorSize != 0)
+                return (false);
+        }
+
+        // if fastest dim is not reduced
+        if constexpr(BetaSrcVectorDim == 0)
+        {
+            if(p_arg_->betaStrides_[NumInvariantDim - 1] != 1)
+                return (false);
+
+            if(p_arg_->invariant_lowest_length % BetaSrcVectorSize != 0)
+                return (false);
+        }
+        else // if fastest dim is reduced
+        {
+            if(p_arg_->betaStrides_[Rank - 1] != 1)
+                return (false);
+
+            if(p_arg_->Lengths_[Rank - 1] % BetaSrcVectorSize != 0)
+                return (false);
+        }
+
+        return true;
+    };
+
+    std::unique_ptr<BaseArgument>
+    MakeArgumentPointer(const std::vector<index_t> lengths,
+                        const std::vector<index_t> xStrides,
+                        const std::vector<index_t> gammaStrides,
+                        const std::vector<index_t> betaStrides,
+                        const std::vector<index_t> yStrides,
+                        const std::vector<index_t> reduceDims,
+                        double epsilon,
+                        const void* p_x,
+                        const void* p_gamma,
+                        const void* p_beta,
+                        void* p_y,
+                        void* p_saveMean,
+                        void* p_saveInvVar,
+                        YElementwiseOperation y_elementwise_op) override
+    {
+        // TODO
+        // Optional cache of the intermediate results (mean and InvVariance) during the
+        // forward pass could speedup in the backward
+        ignore = p_saveMean;
+        ignore = p_saveInvVar;
+
+        return std::make_unique<Argument>(lengths,
+                                          xStrides,
+                                          gammaStrides,
+                                          betaStrides,
+                                          yStrides,
+                                          reduceDims,
+                                          y_elementwise_op,
+                                          epsilon,
+                                          static_cast<const XDataType*>(p_x),
+                                          static_cast<const GammaDataType*>(p_gamma),
+                                          static_cast<const BetaDataType*>(p_beta),
+                                          static_cast<YDataType*>(p_y));
+    };
+
+    std::unique_ptr<BaseInvoker> MakeInvokerPointer() override
+    {
+        return std::make_unique<Invoker>();
+    };
+
+    std::string GetTypeString() const override
+    {
+        auto str = std::stringstream();
+
+        // clang-format off
+        str << "DeviceNormalizationImpl<" << BlockSize << ",";
+        str << "Cluster_MK_" << MThreadClusterSize << "_" << KThreadClusterSize << ",";
+        str << "Slice_MK_" << MThreadSliceSize << "_" << KThreadSliceSize << ",";
+        str << "XYSrcVectorDim_" << XYSrcVectorDim  << ",";
+        str << "VectorSize_X" << XSrcVectorSize << "_Gamma" << GammaSrcVectorSize << "_Beta" << BetaSrcVectorSize << "_Y" << YDstVectorSize << ">";
+        // clang-format on
+
+        return str.str();
+    }
+};
+
+} // namespace device
+} // namespace tensor_operation
+} // namespace ck

include/ck/tensor_operation/gpu/grid/normalization/gridwise_normalization_splitk_1st.hpp

+// SPDX-License-Identifier: MIT
+// Copyright (c) 2018-2022, Advanced Micro Devices, Inc. All rights reserved.
+
+#pragma once
+
+#include "ck/utility/data_type.hpp"
+#include "ck/utility/math.hpp"
+#include "ck/tensor_operation/gpu/block/blockwise_welford.hpp"
+#include "ck/tensor_operation/gpu/thread/threadwise_welford.hpp"
+#include "ck/tensor_operation/gpu/thread/threadwise_tensor_slice_transfer.hpp"
+#include "ck/tensor_operation/gpu/element/element_wise_operation.hpp"
+
+namespace ck {
+
+template <typename XDataType,
+          typename ComputeDataType,
+          typename MeanVarDataType,
+          typename XGridDesc_M_K,
+          typename MeanVarGridDesc_M_KBlock,
+          index_t BlockSize,
+          index_t MThreadClusterSize,
+          index_t KThreadClusterSize,
+          index_t MThreadSliceSize,
+          index_t KThreadSliceSize,
+          index_t XSrcVectorDim,
+          index_t XSrcVectorSize>
+struct GridwiseNormalizationSplitK1st
+{
+    static_assert((XSrcVectorDim == 0 && MThreadSliceSize % XSrcVectorSize == 0) ||
+                      (XSrcVectorDim == 1 && KThreadSliceSize % XSrcVectorSize == 0),
+                  "Invalid thread slice sizes and/or vector sizes configuration, please check!");
+
+    static constexpr bool reorder_thread_cluster = (XSrcVectorDim == 0);
+
+    static constexpr auto I0 = Number<0>{};
+    static constexpr auto I1 = Number<1>{};
+    static constexpr auto I2 = Number<2>{};
+
+    using ThreadClusterLengths_M_K = Sequence<MThreadClusterSize, KThreadClusterSize>;
+
+    using ThreadBufferDimAccessOrder =
+        typename conditional<reorder_thread_cluster, Sequence<1, 0>, Sequence<0, 1>>::type;
+
+    using ThreadClusterArrangeOrder =
+        typename conditional<reorder_thread_cluster, Sequence<1, 0>, Sequence<0, 1>>::type;
+
+    static constexpr auto thread_cluster_desc =
+        make_cluster_descriptor(ThreadClusterLengths_M_K{}, ThreadClusterArrangeOrder{});
+
+    using ThreadBufferLengths_M_K                = Sequence<MThreadSliceSize, XSrcVectorSize>;
+    static constexpr auto thread_buffer_desc_m_k = make_naive_tensor_descriptor_packed(
+        make_tuple(Number<MThreadSliceSize>{}, Number<XSrcVectorSize>{}));
+
+    using ThreadBufferLengths_M_1 = Sequence<MThreadSliceSize, 1>;
+    static constexpr auto thread_buffer_desc_m_1 =
+        make_naive_tensor_descriptor_packed(make_tuple(Number<MThreadSliceSize>{}, I1));
+
+    using ThreadReduceSrcDesc_M_K = decltype(make_naive_tensor_descriptor_packed(
+        make_tuple(Number<MThreadSliceSize>{}, Number<XSrcVectorSize>{})));
+    using ThreadReduceDstDesc_M =
+        decltype(make_naive_tensor_descriptor_packed(make_tuple(Number<MThreadSliceSize>{})));
+
+    using ThreadwiseWelford =
+        ThreadwiseWelford<ComputeDataType, ThreadReduceSrcDesc_M_K, ThreadReduceDstDesc_M>;
+
+    using BlockwiseWelford = BlockwiseWelford<ComputeDataType,
+                                              BlockSize,
+                                              ThreadClusterLengths_M_K,
+                                              ThreadClusterArrangeOrder,
+                                              false>;
+
+    using PassThroughOp = tensor_operation::element_wise::PassThrough;
+
+    static constexpr index_t M_BlockTileSize     = MThreadClusterSize * MThreadSliceSize;
+    static constexpr index_t K_BlockTileSize     = KThreadClusterSize * KThreadSliceSize;
+    static constexpr index_t K_BlockTileStepSize = KThreadClusterSize * XSrcVectorSize;
+
+    static constexpr auto ThreadBufferNumber = Number<KThreadSliceSize / XSrcVectorSize>{};
+
+    __device__ static int
+    GetKPerThread(int kRaw, int kGridSize, int block_k_cluster_id, int thread_k_cluster_id)
+    {
+        bool is_rightmost_block = block_k_cluster_id == kGridSize - 1;
+
+        if(is_rightmost_block)
+        {
+            int left_kPerBlock = math::integer_divide_ceil(kRaw, kGridSize);
+            int kPerBlock      = kRaw % kGridSize == 0 ? left_kPerBlock : kRaw % left_kPerBlock;
+            int kPerThread =
+                kPerBlock < K_BlockTileSize ? 0 : KThreadSliceSize * (kPerBlock / K_BlockTileSize);
+            int kPerBlockTail = kPerBlock - kPerThread * KThreadClusterSize;
+
+            if(kPerBlockTail > 0)
+            {
+                static_for<0, ThreadBufferNumber, 1>{}([&](auto i) {
+                    int thread_max_len =
+                        (thread_k_cluster_id + 1) * XSrcVectorSize + K_BlockTileStepSize * i;
+                    int delta = thread_max_len - kPerBlockTail;
+                    delta     = math::clamp(thread_max_len - kPerBlockTail, 0, XSrcVectorSize);
+                    kPerThread += XSrcVectorSize - delta;
+                });
+            }
+
+            return kPerThread;
+        }
+        else
+        {
+            int kPerBlock = math::integer_divide_ceil(kRaw, kGridSize);
+            return KThreadSliceSize * (kPerBlock / K_BlockTileSize);
+        }
+    }
+
+    // Calculate mean and variance by welford along k dimension
+    __device__ static void Run(const XGridDesc_M_K& x_grid_desc_m_k,
+                               const MeanVarGridDesc_M_KBlock& mean_var_grid_desc_m_kblock,
+                               index_t num_k_block_tile_iteration,
+                               const XDataType* const __restrict__ p_x_global,
+                               MeanVarDataType* const p_mean_global,
+                               MeanVarDataType* const p_variance_global,
+                               int32_t* const p_welford_count_global)
+    {
+        auto x_thread_buf = generate_tuple(
+            [&](auto) {
+                return StaticBuffer<AddressSpaceEnum::Vgpr,
+                                    ComputeDataType,
+                                    MThreadSliceSize * XSrcVectorSize,
+                                    true>{};
+            },
+            Number<ThreadBufferNumber>{});
+
+        StaticBuffer<AddressSpaceEnum::Vgpr, ComputeDataType, MThreadSliceSize, true>
+            mean_thread_buf;
+        StaticBuffer<AddressSpaceEnum::Vgpr, ComputeDataType, MThreadSliceSize, true>
+            var_thread_buf;
+
+        const index_t thread_local_id = get_thread_local_1d_id();
+        const index_t block_global_id = get_block_1d_id();
+
+        const index_t k_grid_size        = mean_var_grid_desc_m_kblock.GetLength(I1);
+        const index_t block_m_cluster_id = block_global_id / k_grid_size;
+        const index_t block_k_cluster_id = block_global_id % k_grid_size;
+
+        const auto thread_cluster_idx =
+            thread_cluster_desc.CalculateBottomIndex(make_multi_index(thread_local_id));
+
+        const auto thread_m_cluster_id = thread_cluster_idx[I0];
+        const auto thread_k_cluster_id = thread_cluster_idx[I1];
+
+        const index_t reduceSizePerBlock = K_BlockTileSize * num_k_block_tile_iteration;
+
+        auto threadwise_x_load = ThreadwiseTensorSliceTransfer_v2<XDataType,
+                                                                  ComputeDataType,
+                                                                  XGridDesc_M_K,
+                                                                  decltype(thread_buffer_desc_m_k),
+                                                                  ThreadBufferLengths_M_K,
+                                                                  ThreadBufferDimAccessOrder,
+                                                                  XSrcVectorDim,
+                                                                  XSrcVectorSize,
+                                                                  1,
+                                                                  true>(
+            x_grid_desc_m_k,
+            make_multi_index(
+                block_m_cluster_id * M_BlockTileSize + thread_m_cluster_id * MThreadSliceSize,
+                block_k_cluster_id * reduceSizePerBlock + thread_k_cluster_id * XSrcVectorSize));
+
+        auto mean_var_count_store_index = make_multi_index(
+            block_m_cluster_id * M_BlockTileSize + thread_m_cluster_id * MThreadSliceSize,
+            block_k_cluster_id);
+
+        auto threadwise_welford_mean_var_store =
+            ThreadwiseTensorSliceTransfer_v1r3<ComputeDataType,
+                                               MeanVarDataType,
+                                               decltype(thread_buffer_desc_m_1),
+                                               MeanVarGridDesc_M_KBlock,
+                                               PassThroughOp,
+                                               ThreadBufferLengths_M_1,
+                                               Sequence<0, 1>,
+                                               1,
+                                               1,
+                                               InMemoryDataOperationEnum::Set,
+                                               1,
+                                               true>(
+                mean_var_grid_desc_m_kblock, mean_var_count_store_index, PassThroughOp{});
+
+        constexpr auto thread_copy_fwd_step_m_k = make_multi_index(0, K_BlockTileStepSize);
+
+        const auto x_global_val_buf = make_dynamic_buffer<AddressSpaceEnum::Global>(
+            p_x_global, x_grid_desc_m_k.GetElementSpaceSize());
+
+        auto mean_global_val_buf = make_dynamic_buffer<AddressSpaceEnum::Global>(
+            p_mean_global, mean_var_grid_desc_m_kblock.GetElementSpaceSize());
+
+        auto var_global_val_buf = make_dynamic_buffer<AddressSpaceEnum::Global>(
+            p_variance_global, mean_var_grid_desc_m_kblock.GetElementSpaceSize());
+
+        auto threadwise_welford = ThreadwiseWelford();
+        int kRaw                = x_grid_desc_m_k.GetTransforms()[I2].GetUpperLengths()[I0];
+        threadwise_welford.max_count_ =
+            GetKPerThread(kRaw, k_grid_size, block_k_cluster_id, thread_k_cluster_id);
+
+        static_for<0, MThreadSliceSize, 1>{}([&](auto I) {
+            mean_thread_buf(I) = type_convert<ComputeDataType>(0.0f);
+            var_thread_buf(I)  = type_convert<ComputeDataType>(0.0f);
+        });
+
+        for(index_t reducedTiles = 0; reducedTiles < num_k_block_tile_iteration; ++reducedTiles)
+        {
+            static_for<0, ThreadBufferNumber, 1>{}([&](auto i) {
+                threadwise_x_load.Run(x_grid_desc_m_k,
+                                      x_global_val_buf,
+                                      thread_buffer_desc_m_k,
+                                      make_tuple(I0, I0),
+                                      x_thread_buf(i));
+                threadwise_x_load.MoveSrcSliceWindow(x_grid_desc_m_k, thread_copy_fwd_step_m_k);
+                threadwise_welford.Run(x_thread_buf[i], mean_thread_buf, var_thread_buf);
+            });
+        }
+
+        static_for<0, MThreadSliceSize, 1>{}([&](auto I) {
+            if constexpr(I > 0)
+                block_sync_lds();
+
+            int count = threadwise_welford.cur_count_;
+            BlockwiseWelford::Run(mean_thread_buf(I), var_thread_buf(I), count);
+        });
+
+        if(thread_k_cluster_id == 0)
+        {
+            threadwise_welford_mean_var_store.Run(thread_buffer_desc_m_1,
+                                                  make_tuple(I0, I0),
+                                                  mean_thread_buf,
+                                                  mean_var_grid_desc_m_kblock,
+                                                  mean_global_val_buf);
+
+            threadwise_welford_mean_var_store.Run(thread_buffer_desc_m_1,
+                                                  make_tuple(I0, I0),
+                                                  var_thread_buf,
+                                                  mean_var_grid_desc_m_kblock,
+                                                  var_global_val_buf);
+
+            if(block_m_cluster_id == 0 && thread_m_cluster_id == 0)
+                p_welford_count_global[block_k_cluster_id] = threadwise_welford.cur_count_;
+        }
+    }
+};
+
+} // namespace ck