From 7f5eb53351763e128ec2e1dd3c4f72b17b5fbae0 Mon Sep 17 00:00:00 2001 From: Li Min <11663212+limin2021@users.noreply.github.com> Date: Mon, 23 Aug 2021 15:51:55 +0800 Subject: [PATCH] Refactor the organization of layer_norm cuda impl. (#34883) Refactor the organization of layer_norm cuda impl so that it can be reused in fused attention op. Extract the layer_norm cuda impl form layer_norm_op.cu to layer_norm_kernel.cu.h. Define fused/attention_layer_norm.h, which can be used in fused attention op in next PR. --- .../operators/fused/attention_layer_norm.h | 75 ++ paddle/fluid/operators/layer_norm_kernel.cu.h | 881 ++++++++++++++++++ paddle/fluid/operators/layer_norm_op.cu | 870 +---------------- 3 files changed, 959 insertions(+), 867 deletions(-) create mode 100644 paddle/fluid/operators/fused/attention_layer_norm.h create mode 100644 paddle/fluid/operators/layer_norm_kernel.cu.h diff --git a/paddle/fluid/operators/fused/attention_layer_norm.h b/paddle/fluid/operators/fused/attention_layer_norm.h new file mode 100644 index 00000000000..d234a0f0853 --- /dev/null +++ b/paddle/fluid/operators/fused/attention_layer_norm.h @@ -0,0 +1,75 @@ +/* Copyright (c) 2021 PaddlePaddle Authors. All Rights Reserved. + +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. */ + +#pragma once + +#include "paddle/fluid/operators/layer_norm_kernel.cu.h" + +namespace paddle { +namespace operators { + +template +class AttnLayerNorm { + public: + AttnLayerNorm(const platform::CUDADeviceContext& dev_ctx, float epsilon, + int64_t batch_size, int64_t feature_size) + : dev_ctx_(dev_ctx), + epsilon_(epsilon), + batch_size_(batch_size), + feature_size_(feature_size) {} + + ~AttnLayerNorm() {} + + void ComputeForward(const T* x_data, const LayerNormParamType* scale_data, + const LayerNormParamType* bias_data, T* y_data, + LayerNormParamType* mean_data, + LayerNormParamType* var_data) { + auto stream = dev_ctx_.stream(); + + switch (GetDesiredBlockDim(feature_size_)) { + FIXED_BLOCK_DIM_CASE( + LayerNormForward, + kBlockDim><<>>( + x_data, scale_data, bias_data, y_data, mean_data, var_data, + epsilon_, feature_size_)); + default: + PADDLE_THROW(platform::errors::InvalidArgument( + "Feature_size must be larger than 1")); + break; + } + } + + void ComputeBackward(const T* x_data， const T* y_data, + const LayerNormParamType* scale_data, + const LayerNormParamType* mean_data, + const LayerNormParamType* var_data, T* d_x_data, + LayerNormParamType* d_scale_data, + LayerNormParamType* d_bias_data) { + LayerNormBackward>( + x_data, d_y_data, scale_data, mean_data, var_data, d_x_data, + d_scale_data, d_bias_data, epsilon_, batch_size_, feature_size_, + dev_ctx_); + } + + private: + const platform::CUDADeviceContext& dev_ctx_; + + int64_t batch_size_; + int64_t feature_size_; + + float epsilon_; +}; + +} // namespace operators +} // namespace paddle diff --git a/paddle/fluid/operators/layer_norm_kernel.cu.h b/paddle/fluid/operators/layer_norm_kernel.cu.h new file mode 100644 index 00000000000..37f7e8c5590 --- /dev/null +++ b/paddle/fluid/operators/layer_norm_kernel.cu.h @@ -0,0 +1,881 @@ +/* Copyright (c) 2021 PaddlePaddle Authors. All Rights Reserved. + +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. */ + +#pragma once + +#ifdef __NVCC__ +#include "cub/cub.cuh" +#endif +#ifdef __HIPCC__ +#include +namespace cub = hipcub; +#endif + +#include "paddle/fluid/framework/ddim.h" +#include "paddle/fluid/platform/cuda_device_function.h" +#ifdef PADDLE_WITH_CUDA +#include "paddle/fluid/platform/cudnn_helper.h" +#endif +#ifdef PADDLE_WITH_HIP +#include "paddle/fluid/platform/miopen_helper.h" +#endif + +namespace paddle { +namespace operators { + +using Tensor = framework::Tensor; +using DataLayout = framework::DataLayout; +template +using CudnnDataType = platform::CudnnDataType; +template +using LayerNormParamType = typename CudnnDataType::BatchNormParamType; + +inline static int GetDesiredBlockDim(int64_t block_dim) { +#ifdef __HIPCC__ + const int kMaxBlockDim = 256; + const int lwarpSize = 64; +#else + const int kMaxBlockDim = 512; + const int lwarpSize = 32; +#endif + return block_dim >= kMaxBlockDim ? kMaxBlockDim : lwarpSize; +} + +template +static __forceinline__ __device__ U WarpReduceSum(U val) { + unsigned mask = 0u; + CREATE_SHFL_MASK(mask, true); + for (int offset = warpSize / 2; offset > 0; offset /= 2) { + val += paddle::platform::CudaShuffleDownSync(mask, val, offset); + } + return val; +} + +template +__forceinline__ __device__ U BlockReduceSum(U val, U *shared) { + int lane = threadIdx.x % warpSize; + int wid = threadIdx.x / warpSize; + + val = WarpReduceSum(val); // Each warp performs partial reduction + + __syncthreads(); + if (lane == 0) shared[wid] = val; // Write reduced value to shared memory + + __syncthreads(); // Wait for all partial reductions + // read from shared memory only if that warp existed + val = + (threadIdx.x < blockDim.x / warpSize) ? shared[lane] : static_cast(0); + + if (wid == 0) val = WarpReduceSum(val); // Final reduce within first warp + + return val; +} + +#define FIXED_BLOCK_DIM_CASE_BASE(log2_block_dim, ...) \ + case (1 << (log2_block_dim)): { \ + constexpr auto kBlockDim = (1 << (log2_block_dim)); \ + __VA_ARGS__; \ + } break + +#define FIXED_BLOCK_DIM_CASE(...) \ + FIXED_BLOCK_DIM_CASE_BASE(9, ##__VA_ARGS__); \ + FIXED_BLOCK_DIM_CASE_BASE(8, ##__VA_ARGS__); \ + FIXED_BLOCK_DIM_CASE_BASE(7, ##__VA_ARGS__); \ + FIXED_BLOCK_DIM_CASE_BASE(6, ##__VA_ARGS__); \ + FIXED_BLOCK_DIM_CASE_BASE(5, ##__VA_ARGS__); \ + FIXED_BLOCK_DIM_CASE_BASE(4, ##__VA_ARGS__); \ + FIXED_BLOCK_DIM_CASE_BASE(3, ##__VA_ARGS__); \ + FIXED_BLOCK_DIM_CASE_BASE(2, ##__VA_ARGS__); \ + FIXED_BLOCK_DIM_CASE_BASE(1, ##__VA_ARGS__) + +#define FIXED_BLOCK_DIM_FIXED_BLOCK_NUM_CASE_BASE( \ + log2_block_dim, feature_size, kMaxBlockNum, ...) \ + case (1 << (log2_block_dim)): { \ + for (int64_t i = 0; i < std::ceil(feature_size / (1.0 * kMaxBlockNum)); \ + i++) { \ + int64_t col_offset = i * static_cast(kMaxBlockNum); \ + int block_num = static_cast(std::min( \ + feature_size - col_offset, static_cast(kMaxBlockNum))); \ + constexpr auto kBlockDim = (1 << (log2_block_dim)); \ + __VA_ARGS__; \ + } \ + } break + +#define FIXED_BLOCK_DIM_FIXED_BLOCK_NUM_CASE(feature_size, kMaxBlockNum, ...) \ + FIXED_BLOCK_DIM_FIXED_BLOCK_NUM_CASE_BASE(9, feature_size, kMaxBlockNum, \ + ##__VA_ARGS__); \ + FIXED_BLOCK_DIM_FIXED_BLOCK_NUM_CASE_BASE(8, feature_size, kMaxBlockNum, \ + ##__VA_ARGS__); \ + FIXED_BLOCK_DIM_FIXED_BLOCK_NUM_CASE_BASE(7, feature_size, kMaxBlockNum, \ + ##__VA_ARGS__); \ + FIXED_BLOCK_DIM_FIXED_BLOCK_NUM_CASE_BASE(6, feature_size, kMaxBlockNum, \ + ##__VA_ARGS__); \ + FIXED_BLOCK_DIM_FIXED_BLOCK_NUM_CASE_BASE(5, feature_size, kMaxBlockNum, \ + ##__VA_ARGS__); \ + FIXED_BLOCK_DIM_FIXED_BLOCK_NUM_CASE_BASE(4, feature_size, kMaxBlockNum, \ + ##__VA_ARGS__); \ + FIXED_BLOCK_DIM_FIXED_BLOCK_NUM_CASE_BASE(3, feature_size, kMaxBlockNum, \ + ##__VA_ARGS__); \ + FIXED_BLOCK_DIM_FIXED_BLOCK_NUM_CASE_BASE(2, feature_size, kMaxBlockNum, \ + ##__VA_ARGS__); \ + FIXED_BLOCK_DIM_FIXED_BLOCK_NUM_CASE_BASE(1, feature_size, kMaxBlockNum, \ + ##__VA_ARGS__) + +static __device__ __forceinline__ float real_sqrt(float x) { return sqrtf(x); } +static __device__ __forceinline__ double real_sqrt(double x) { return sqrt(x); } + +template +struct PairForLayerNorm { + __device__ __forceinline__ PairForLayerNorm() {} + __device__ __forceinline__ PairForLayerNorm(const T &first, const T &second) + : first_(first), second_(second) {} + + T first_; + T second_; +}; + +template +struct PairForLayerNormAddFunctor { + __device__ __forceinline__ PairForLayerNorm operator()( + const PairForLayerNorm &p1, const PairForLayerNorm &p2) { + return PairForLayerNorm(p1.first_ + p2.first_, p1.second_ + p2.second_); + } +}; + +template +__inline__ __device__ T rsqrt_(const T val) { + return static_cast(1) / sqrt(val); +} + +template <> +__inline__ __device__ float rsqrt_(const float val) { + return rsqrtf(val); +} + +template <> +__inline__ __device__ double rsqrt_(const double val) { + return rsqrt(val); +} + +#if CUDA_ARCH_FP16_SUPPORTED(__CUDA_ARCH__) +template <> +__inline__ __device__ half rsqrt_(const half val) { + return hrsqrt(val); +} +#endif + +template +__global__ void LayerNormForward(const T *x, const U *scale, const U *bias, + T *y, U *mean, U *var, float epsilon, + int64_t feature_size) { + __shared__ U mean_share; + __shared__ U var_share; + __shared__ U shared_mean[32]; // threadIdx.x / warpSize <= kMaxBlockDim / + // warpSize <= 1024/32 = 32; + __shared__ U shared_var[32]; + + int64_t beg_idx = blockIdx.x * feature_size + threadIdx.x; + int64_t end_idx = (blockIdx.x + 1) * feature_size; + + // Step 1: Reduce to calculate mean and var + U mean_val = 0; + U var_val = 0; + for (int64_t i = beg_idx; i < end_idx; i += BlockDim) { + U tmp = static_cast(x[i]); + mean_val += tmp; + var_val += (tmp * tmp); + } + + mean_val = BlockReduceSum(mean_val, shared_mean); + var_val = BlockReduceSum(var_val, shared_var); + + if (threadIdx.x == 0) { + auto scale = static_cast(1.) / static_cast(feature_size); + auto tmp = mean_val * scale; + mean[blockIdx.x] = mean_share = static_cast(tmp); + var_share = static_cast(var_val * scale - mean_share * mean_share); + var_share = var_share > U(0) ? var_share : U(0); + var[blockIdx.x] = var_share; + } + __syncthreads(); + + mean_val = mean_share; + U invvar = rsqrt_(var_share + static_cast(epsilon)); + + // Step 2: Calculate y + if (scale != nullptr) { + if (bias != nullptr) { + for (int64_t i = beg_idx, j = threadIdx.x; i < end_idx; + i += BlockDim, j += BlockDim) { + y[i] = static_cast( + scale[j] * (static_cast(x[i]) - mean_val) * invvar + bias[j]); + } + } else { + for (int64_t i = beg_idx, j = threadIdx.x; i < end_idx; + i += BlockDim, j += BlockDim) { + y[i] = static_cast(scale[j] * (static_cast(x[i]) - mean_val) * + invvar); + } + } + } else { // scale == nullptr + if (bias != nullptr) { + for (int64_t i = beg_idx, j = threadIdx.x; i < end_idx; + i += BlockDim, j += BlockDim) { + y[i] = static_cast((static_cast(x[i]) - mean_val) * invvar + + bias[j]); + } + } else { + for (int64_t i = beg_idx, j = threadIdx.x; i < end_idx; + i += BlockDim, j += BlockDim) { + y[i] = static_cast((static_cast(x[i]) - mean_val) * invvar); + } + } + } +} + +template +__inline__ __device__ void cuLoadAddStridedInputs( + const int64_t i1_block, const int thr_load_row_off, + const int thr_load_col_off, const int i2_off, const int row_stride, + U *warp_buf1, U *warp_buf2, const T *input, const T *dout, + const int64_t i1_end, const int64_t n2, const U *__restrict__ mean, + const U *__restrict__ var, const float epsilon) { + const int64_t i1 = i1_block + thr_load_row_off; + if (i1 >= i1_end) return; + U curr_mean = mean[i1]; + U curr_invvar = rsqrt_(var[i1] + epsilon); + for (int k = 0; k < VPT; ++k) { + const int i2 = i2_off + k; + const int64_t load_idx = i1 * n2 + i2; + const int write_idx = thr_load_row_off * row_stride + thr_load_col_off + k; + if (i2 < n2) { + U curr_input = static_cast(input[load_idx]); + U curr_dout = static_cast(dout[load_idx]); + warp_buf1[write_idx] += curr_dout; + warp_buf2[write_idx] += + curr_dout * (curr_input - curr_mean) * curr_invvar; + } + } +} + +template +__global__ void LayerNormBackwardPartGradGammaBeta( + const T *__restrict__ dout, const T *__restrict__ input, const int64_t n1, + const int64_t n2, const U *__restrict__ mean, const U *__restrict__ var, + float epsilon, U *part_grad_gamma, U *part_grad_beta) { + // VPTX -> value per thread.x, BDIMX -> blockDim.x, BDIMY -> blockDim.y, BDIMX + // -> blockDim.x + // template for compile time optimizations + + constexpr int row_stride = BDIMX + 1; + const int thr_load_col_off = (threadIdx.x * VPTX) & (BDIMX - 1); + const int thr_load_row_off = + (threadIdx.x * VPTX) / BDIMX + threadIdx.y * BDIMY; + const int i2_off = blockIdx.x * BDIMX + thr_load_col_off; + + constexpr int shared_cap = (BDIMX * BDIMY > 2 * VPTX * BDIMY * row_stride) + ? BDIMX * BDIMY + : 2 * VPTX * BDIMY * row_stride; + __shared__ U buf[shared_cap]; + + U *warp_buf1 = reinterpret_cast(buf); + U *warp_buf2 = warp_buf1 + VPTX * BDIMY * row_stride; + + for (int idx = threadIdx.y * blockDim.x + threadIdx.x; + idx < 2 * VPTX * BDIMY * row_stride; idx += BDIMX * BDIMY) { + buf[idx] = U(0); + } + __syncthreads(); + + for (int64_t i1_block = blockIdx.y * BDIMY * VPTX; i1_block < n1; + i1_block += VPTX * BDIMY * gridDim.y) { + cuLoadAddStridedInputs( + i1_block, thr_load_row_off, thr_load_col_off, i2_off, row_stride, + warp_buf1, warp_buf2, input, dout, n1, n2, mean, var, epsilon); + } + __syncthreads(); + + // inter-warp reductions + // sum within each warp + U acc1 = U(0); + U acc2 = U(0); + for (int k = 0; k < VPTX; ++k) { + int row1 = threadIdx.y + k * VPTX; + int idx1 = row1 * row_stride + threadIdx.x; + acc1 += warp_buf1[idx1]; + acc2 += warp_buf2[idx1]; + } + warp_buf1[threadIdx.y * row_stride + threadIdx.x] = acc1; + warp_buf2[threadIdx.y * row_stride + threadIdx.x] = acc2; + __syncthreads(); + // sum all warps + for (int offset = VPTX >> 1; offset > 1; offset >>= 1) { + if (threadIdx.y < offset) { + int row1 = threadIdx.y; + int row2 = threadIdx.y + offset; + int idx1 = row1 * row_stride + threadIdx.x; + int idx2 = row2 * row_stride + threadIdx.x; + warp_buf1[idx1] += warp_buf1[idx2]; + warp_buf2[idx1] += warp_buf2[idx2]; + } + __syncthreads(); + } + int64_t i2 = blockIdx.x * blockDim.x + threadIdx.x; + if (threadIdx.y == 0 && i2 < n2) { + int row1 = threadIdx.y; + int row2 = threadIdx.y + 1; + int idx1 = row1 * row_stride + threadIdx.x; + int idx2 = row2 * row_stride + threadIdx.x; + part_grad_beta[blockIdx.y * n2 + i2] = warp_buf1[idx1] + warp_buf1[idx2]; + part_grad_gamma[blockIdx.y * n2 + i2] = warp_buf2[idx1] + warp_buf2[idx2]; + } +} + +template +__global__ void LayerNormBackwardSumGradGammaBeta( + const U *part_grad_gamma, const U *part_grad_beta, const int part_size, + // const int n1, const int n2, T* grad_gamma, T* grad_beta) { + const int n1, const int n2, U *grad_gamma, U *grad_beta) { + // sum partial gradients for gamma and beta + __shared__ U buf[BDIMX * BDIMY]; + int64_t i2 = blockIdx.x * BDIMX + threadIdx.x; + if (i2 < n2) { + // each warp does sequential reductions until reduced part_size is num_warps + int num_warp_reductions = part_size / BDIMY; + U sum_gamma = U(0); + U sum_beta = U(0); + const U *part_grad_gamma_ptr = + part_grad_gamma + threadIdx.y * num_warp_reductions * n2 + i2; + const U *part_grad_beta_ptr = + part_grad_beta + threadIdx.y * num_warp_reductions * n2 + i2; + for (int warp_offset = 0; warp_offset < num_warp_reductions; + ++warp_offset) { + sum_gamma += part_grad_gamma_ptr[warp_offset * n2]; + sum_beta += part_grad_beta_ptr[warp_offset * n2]; + } + // inter-warp reductions + constexpr int nbsize3 = BDIMX * BDIMY / 2; + for (int offset = BDIMY / 2; offset >= 1; offset /= 2) { + // top half write to shared memory + if (threadIdx.y >= offset && threadIdx.y < 2 * offset) { + const int write_idx = (threadIdx.y - offset) * blockDim.x + threadIdx.x; + buf[write_idx] = sum_gamma; + buf[write_idx + nbsize3] = sum_beta; + } + __syncthreads(); + // bottom half sums + if (threadIdx.y < offset) { + const int read_idx = threadIdx.y * BDIMX + threadIdx.x; + sum_gamma += buf[read_idx]; + sum_beta += buf[read_idx + nbsize3]; + } + __syncthreads(); + } + // write out fully summed gradients + if (threadIdx.y == 0) { + grad_gamma[i2] = sum_gamma; + grad_beta[i2] = sum_beta; + } + } +} + +template +__global__ void LayerNormBackwardComputeGradInput( + const T *__restrict__ dout, const T *__restrict__ input, const int n1, + const int n2, + // const U* __restrict__ mean, const U* __restrict__ var, const float + // epsilon, const T* gamma, + const U *__restrict__ mean, const U *__restrict__ var, const float epsilon, + const U *gamma, T *grad_input) { +#ifdef __HIPCC__ + for (auto i1 = hipBlockIdx_x; i1 < n1; i1 += hipGridDim_x) { +#else + for (auto i1 = blockIdx.x; i1 < n1; i1 += gridDim.x) { +#endif + U sum_loss1 = U(0); + U sum_loss2 = U(0); + const U c_mean = mean[i1]; + const U c_invvar = rsqrt_(var[i1] + epsilon); + const T *k_input = input + i1 * n2; + const T *k_dout = dout + i1 * n2; + constexpr int numx = BDIMX * BDIMY; + const int thrx = threadIdx.x + threadIdx.y * BDIMX; + if (gamma != NULL) { + int l = 4 * thrx; + for (; l + 3 < n2; l += 4 * numx) { + for (int k = 0; k < 4; ++k) { + const U c_h = static_cast(k_input[l + k]); + const U c_loss = static_cast(k_dout[l + k]); + sum_loss1 += c_loss * gamma[l + k]; + sum_loss2 += c_loss * gamma[l + k] * (c_h - c_mean) * c_invvar; + } + } + for (; l < n2; ++l) { + const U c_h = static_cast(k_input[l]); + const U c_loss = static_cast(k_dout[l]); + sum_loss1 += c_loss * gamma[l]; + sum_loss2 += c_loss * gamma[l] * (c_h - c_mean) * c_invvar; + } + } else { + int l = 4 * thrx; + for (; l + 3 < n2; l += 4 * numx) { + for (int k = 0; k < 4; ++k) { + const U c_h = static_cast(k_input[l + k]); + const U c_loss = static_cast(k_dout[l + k]); + sum_loss1 += c_loss; + sum_loss2 += c_loss * (c_h - c_mean) * c_invvar; + } + } + for (; l < n2; ++l) { + const U c_h = static_cast(k_input[l]); + const U c_loss = static_cast(k_dout[l]); + sum_loss1 += c_loss; + sum_loss2 += c_loss * (c_h - c_mean) * c_invvar; + } + } + // intra-warp reductions + for (int mask = BDIMX / 2; mask > 0; mask /= 2) { +#ifdef PADDLE_WITH_HIP + sum_loss1 += __shfl_xor(sum_loss1, mask, + warpSize); // WARP_SHFL_XOR(sum_loss1, mask); + sum_loss2 += __shfl_xor(sum_loss2, mask, + warpSize); // WARP_SHFL_XOR(sum_loss2, mask); +#else + sum_loss1 += + __shfl_xor_sync(0xffffffff, sum_loss1, mask, + warpSize); // WARP_SHFL_XOR(sum_loss1, mask); + sum_loss2 += + __shfl_xor_sync(0xffffffff, sum_loss2, mask, + warpSize); // WARP_SHFL_XOR(sum_loss2, mask); +#endif + } + // inter-warp reductions + if (BDIMY > 1) { + __shared__ U buf[BDIMX * BDIMY]; + for (int offset = BDIMY / 2; offset > 0; offset /= 2) { + // upper half of warps write to shared + if (threadIdx.y >= offset && threadIdx.y < 2 * offset) { + const int wrt_i = (threadIdx.y - offset) * BDIMX + threadIdx.x; + buf[2 * wrt_i] = sum_loss1; + buf[2 * wrt_i + 1] = sum_loss2; + } + __syncthreads(); + // lower half merges + if (threadIdx.y < offset) { + const int read_i = threadIdx.y * blockDim.x + threadIdx.x; + sum_loss1 += buf[2 * read_i]; + sum_loss2 += buf[2 * read_i + 1]; + } + __syncthreads(); + } + if (threadIdx.y == 0) { + buf[2 * threadIdx.x] = sum_loss1; + buf[2 * threadIdx.x + 1] = sum_loss2; + } + __syncthreads(); + if (threadIdx.y != 0) { + sum_loss1 = buf[2 * threadIdx.x]; + sum_loss2 = buf[2 * threadIdx.x + 1]; + } + } + // all threads now have the two sums over l + U fH = (U)n2; + U term1 = (U(1) / fH) * c_invvar; + T *k_grad_input = grad_input + i1 * n2; + if (gamma != NULL) { + for (int l = thrx; l < n2; l += numx) { + const U c_h = static_cast(k_input[l]); + const U c_loss = static_cast(k_dout[l]); + U f_grad_input = fH * c_loss * gamma[l]; + f_grad_input -= sum_loss1; + f_grad_input -= (c_h - c_mean) * c_invvar * sum_loss2; + f_grad_input *= term1; + k_grad_input[l] = static_cast(f_grad_input); + } + } else { + for (int l = thrx; l < n2; l += numx) { + const U c_h = static_cast(k_input[l]); + const U c_loss = static_cast(k_dout[l]); + U f_grad_input = fH * c_loss; + f_grad_input -= sum_loss1; + f_grad_input -= (c_h - c_mean) * c_invvar * sum_loss2; + f_grad_input *= term1; + k_grad_input[l] = static_cast(f_grad_input); + } + } + } +} + +// Make sure that d_scale != nullptr && d_bias != nullptr +// Since d_scale != nullptr, scale would not be nullptr +template +__global__ void LayerNormBackwardGradientAll( + const T *x, const T *d_y, U *d_scale, U *d_bias, T *d_x, const U *mean, + const U *var, const U *scale, float epsilon, int64_t batch_size, + int64_t feature_size, int64_t col_offset) { + int64_t beg_idx = threadIdx.x * feature_size + (blockIdx.x + col_offset); + int64_t end_idx = batch_size * feature_size + (blockIdx.x + col_offset); + int64_t stride = BlockDim * feature_size; + + U d_scale_partial = static_cast(0), d_bias_partial = static_cast(0); + + for (int64_t i = beg_idx; i < end_idx; i += stride) { + int row_idx = i / feature_size; + auto var_val = real_sqrt(static_cast(var[row_idx]) + epsilon); + d_scale_partial += static_cast(d_y[i]) * + (static_cast(x[i]) - mean[row_idx]) / var_val; + d_bias_partial += static_cast(d_y[i]); + if (HasDx) { + d_x[i] = static_cast(static_cast(d_y[i]) * + scale[blockIdx.x + col_offset] / var_val); + } + } + + __shared__ U shared_scale[32]; // threadIdx.x / warpSize <= kMaxBlockDim / + // warpSize <= 1024/32 = 32; + __shared__ U shared_bias[32]; + d_scale_partial = BlockReduceSum(d_scale_partial, shared_scale); + d_bias_partial = BlockReduceSum(d_bias_partial, shared_bias); + + if (threadIdx.x == 0) { + d_scale[blockIdx.x + col_offset] = d_scale_partial; + d_bias[blockIdx.x + col_offset] = d_bias_partial; + } +} + +// Make sure that there is only one true expression: d_scale != nullptr +// or d_bias != nullptr +// Notice: scale may be nullptr +template +__global__ void LayerNormBackwardGradientScaleOrBias( + const T *x, const T *d_y, U *d_scale, U *d_bias, T *d_x, const U *mean, + const U *var, const U *scale, float epsilon, int64_t batch_size, + int64_t feature_size, int col_offset) { + using BlockReduce = cub::BlockReduce; + __shared__ typename BlockReduce::TempStorage temp_storage; + int64_t beg_idx = threadIdx.x * feature_size + blockIdx.x + col_offset; + int64_t end_idx = batch_size * feature_size + blockIdx.x + col_offset; + int stride = BlockDim * feature_size; + U d_scale_or_d_bias_partial = static_cast(0); + + for (int64_t i = beg_idx; i < end_idx; i += stride) { + int row_idx = i / feature_size; + auto var_val = + static_cast(real_sqrt(static_cast(var[row_idx]) + epsilon)); + if (HasDScale) { + d_scale_or_d_bias_partial += static_cast(d_y[i]) * + (static_cast(x[i]) - mean[row_idx]) / + var_val; + } else { // d_bias != nullptr + d_scale_or_d_bias_partial += static_cast(d_y[i]); + } + + if (HasDx) { + if (scale != nullptr) { + d_x[i] = static_cast(static_cast(d_y[i]) * + scale[blockIdx.x + col_offset] / var_val); + } else { + d_x[i] = static_cast(static_cast(d_y[i]) / var_val); + } + } + } + + d_scale_or_d_bias_partial = + BlockReduce(temp_storage).Reduce(d_scale_or_d_bias_partial, cub::Sum()); + + if (threadIdx.x == 0) { + if (HasDScale) { + d_scale[blockIdx.x + col_offset] = d_scale_or_d_bias_partial; + } else { + d_bias[blockIdx.x + col_offset] = d_scale_or_d_bias_partial; + } + } +} + +template +__global__ void LayerNormBackwardPostProcessToCalculateDX( + const T *x, T *d_x, const U *mean, const U *var, float epsilon, + int64_t feature_size) { + using BlockReduce = cub::BlockReduce, BlockDim>; + __shared__ typename BlockReduce::TempStorage temp_storage; + __shared__ U d_x_reduce_tmp[2]; + + int64_t beg_idx = blockIdx.x * feature_size + threadIdx.x; + int64_t end_idx = (blockIdx.x + 1) * feature_size; + + U block_mean = mean[blockIdx.x]; + U block_var = var[blockIdx.x]; + U d_x_mean_partial = static_cast(0), d_x_var_partial = static_cast(0); + for (int64_t i = beg_idx; i < end_idx; i += BlockDim) { + d_x_mean_partial += static_cast(d_x[i]); + d_x_var_partial += + static_cast(d_x[i]) * (static_cast(x[i]) - block_mean); + } + + auto pair = + BlockReduce(temp_storage) + .Reduce(PairForLayerNorm(d_x_mean_partial, d_x_var_partial), + PairForLayerNormAddFunctor()); + + if (threadIdx.x == 0) { + d_x_reduce_tmp[0] = static_cast(pair.first_) / feature_size; + d_x_reduce_tmp[1] = + static_cast(pair.second_) / + (feature_size * (static_cast(block_var) + epsilon)); + } + __syncthreads(); + + d_x_mean_partial = d_x_reduce_tmp[0]; + d_x_var_partial = d_x_reduce_tmp[1]; + for (int64_t i = beg_idx; i < end_idx; i += BlockDim) { + d_x[i] -= static_cast(d_x_mean_partial); + d_x[i] -= + static_cast((static_cast(x[i]) - block_mean) * d_x_var_partial); + } +} + +// Here, we only calculate d_x +template +__global__ void LayerNormBackwardGradientOnlyDX(const T *x, const T *d_y, + T *d_x, const U *mean, + const U *var, const U *scale, + float epsilon, + int64_t feature_size) { + using BlockReduce = cub::BlockReduce, BlockDim>; + __shared__ typename BlockReduce::TempStorage temp_storage; + __shared__ U d_x_reduce_tmp[2]; + + int64_t beg_idx = blockIdx.x * feature_size + threadIdx.x; + int64_t end_idx = (blockIdx.x + 1) * feature_size; + + U block_mean = mean[blockIdx.x], block_var = var[blockIdx.x]; + U d_x_mean_partial = static_cast(0), d_x_var_partial = static_cast(0); + for (int64_t i = beg_idx; i < end_idx; i += BlockDim) { + auto var_val = + static_cast(real_sqrt(static_cast(block_var) + epsilon)); + if (scale != nullptr) { + int col_idx = i % feature_size; + d_x[i] = + static_cast(static_cast(d_y[i]) * scale[col_idx] / var_val); + } else { + d_x[i] = static_cast(static_cast(d_y[i]) / var_val); + } + d_x_mean_partial += static_cast(d_x[i]); + d_x_var_partial += + static_cast(d_x[i]) * (static_cast(x[i]) - block_mean); + } + + auto pair = + BlockReduce(temp_storage) + .Reduce(PairForLayerNorm(d_x_mean_partial, d_x_var_partial), + PairForLayerNormAddFunctor()); + + if (threadIdx.x == 0) { + d_x_reduce_tmp[0] = static_cast(pair.first_) / feature_size; + d_x_reduce_tmp[1] = + static_cast(pair.second_) / + (feature_size * (static_cast(block_var) + epsilon)); + } + __syncthreads(); + + d_x_mean_partial = d_x_reduce_tmp[0]; + d_x_var_partial = d_x_reduce_tmp[1]; + for (int64_t i = beg_idx; i < end_idx; i += BlockDim) { + d_x[i] -= static_cast(d_x_mean_partial); + d_x[i] -= + static_cast((static_cast(x[i]) - block_mean) * d_x_var_partial); + } +} + +template +__global__ void LayerNormBackwardWhenBatchSizeIsOne( + const T *x, const T *d_y, T *d_x, U *d_scale, U *d_bias, const U *mean, + const U *var, const U *scale, float epsilon, int64_t feature_size) { + int64_t idx = threadIdx.x + blockIdx.x * blockDim.x; + if (idx < feature_size) { + auto var_val = + static_cast(real_sqrt(static_cast(var[idx]) + epsilon)); + if (d_x != nullptr) { + if (d_scale == nullptr) { + d_x[idx] = static_cast(static_cast(d_y[idx]) / var_val); + } else { + d_x[idx] = + static_cast(static_cast(d_y[idx]) * scale[idx] / var_val); + } + } + + if (d_scale != nullptr) { + d_scale[idx] = static_cast(d_y[idx]) * + (static_cast(x[idx]) - mean[idx]) / var_val; + } + + if (d_bias != nullptr) d_bias[idx] = static_cast(d_y[idx]); + } +} + +template +static void LayerNormBackward(const T *x, const T *d_y, const U *scale, + const U *mean, const U *var, T *d_x, U *d_scale, + U *d_bias, float epsilon, int64_t batch_size, + int64_t feature_size, + const platform::CUDADeviceContext &dev_ctx) { + auto stream = dev_ctx.stream(); +#ifdef __HIPCC__ + const int kMaxBlockDim = 256; +#else + const int kMaxBlockDim = 512; +#endif + const int kMaxBlockNum = 128; + int gradient_flag = ((d_x != nullptr ? 1 : 0) << 2) | + ((d_scale != nullptr ? 1 : 0) << 1) | + ((d_bias != nullptr ? 1 : 0)); + if (gradient_flag == 0) return; + + if (batch_size == 1) { + LayerNormBackwardWhenBatchSizeIsOne< + T, U><<<(feature_size + kMaxBlockDim - 1) / kMaxBlockDim, kMaxBlockDim, + 0, stream>>>(x, d_y, d_x, d_scale, d_bias, mean, var, scale, + epsilon, feature_size); + + if (d_x != nullptr) { + switch (GetDesiredBlockDim(feature_size)) { + FIXED_BLOCK_DIM_CASE(LayerNormBackwardPostProcessToCalculateDX< + T, U, kBlockDim><<<1, kBlockDim, 0, stream>>>( + x, d_x, mean, var, epsilon, feature_size)); + } + } + return; + } + + auto block_dim = GetDesiredBlockDim(batch_size); + switch (gradient_flag) { + case 1: // d_x == nulptr, d_scale == nullptr, d_bias != nullptr + switch (block_dim) { + FIXED_BLOCK_DIM_FIXED_BLOCK_NUM_CASE( + feature_size, kMaxBlockNum, + LayerNormBackwardGradientScaleOrBias< + T, U, kBlockDim, false, + false><<>>( + x, d_y, d_scale, d_bias, d_x, mean, var, scale, epsilon, + batch_size, feature_size, col_offset)); + } + break; + case 2: // d_x == nullptr, d_scale != nullptr, d_bias == nullptr + switch (block_dim) { + FIXED_BLOCK_DIM_FIXED_BLOCK_NUM_CASE( + feature_size, kMaxBlockNum, + LayerNormBackwardGradientScaleOrBias< + T, U, kBlockDim, false, + true><<>>( + x, d_y, d_scale, d_bias, d_x, mean, var, scale, epsilon, + batch_size, feature_size, col_offset)); + } + break; + case 3: // d_x == nullptr, d_scale != nulptr, d_bias != nullptr + switch (block_dim) { + FIXED_BLOCK_DIM_FIXED_BLOCK_NUM_CASE( + feature_size, kMaxBlockNum, + LayerNormBackwardGradientAll< + T, U, kBlockDim, false><<>>( + x, d_y, d_scale, d_bias, d_x, mean, var, scale, epsilon, + batch_size, feature_size, col_offset)); + } + break; + case 4: // d_x != nullptr, d_scale == nullptr, d_bias == nullptr + switch (GetDesiredBlockDim(feature_size)) { + FIXED_BLOCK_DIM_CASE( + LayerNormBackwardGradientOnlyDX< + T, U, kBlockDim><<>>( + x, d_y, d_x, mean, var, scale, epsilon, feature_size)); + } + break; + case 5: // d_x != nulptr, d_scale == nullptr, d_bias != nullptr + switch (block_dim) { + FIXED_BLOCK_DIM_FIXED_BLOCK_NUM_CASE( + feature_size, kMaxBlockNum, + LayerNormBackwardGradientScaleOrBias< + T, U, kBlockDim, true, + false><<>>( + x, d_y, d_scale, d_bias, d_x, mean, var, scale, epsilon, + batch_size, feature_size, col_offset)); + } + switch (GetDesiredBlockDim(feature_size)) { + FIXED_BLOCK_DIM_CASE( + LayerNormBackwardPostProcessToCalculateDX< + T, U, kBlockDim><<>>( + x, d_x, mean, var, epsilon, feature_size)); + } + break; + case 6: // d_x != nullptr, d_scale != nullptr, d_bias == nullptr + switch (block_dim) { + FIXED_BLOCK_DIM_FIXED_BLOCK_NUM_CASE( + feature_size, kMaxBlockNum, + LayerNormBackwardGradientScaleOrBias< + T, U, kBlockDim, true, + true><<>>( + x, d_y, d_scale, d_bias, d_x, mean, var, scale, epsilon, + batch_size, feature_size, col_offset)); + } + switch (GetDesiredBlockDim(feature_size)) { + FIXED_BLOCK_DIM_CASE( + LayerNormBackwardPostProcessToCalculateDX< + T, U, kBlockDim><<>>( + x, d_x, mean, var, epsilon, feature_size)); + } + break; + case 7: // d_x != nullptr, d_scale != nullptr, d_bias != nullptr + { + constexpr int VPT = 4; + constexpr int BDIMX2 = 32; + constexpr int BDIMY2 = 4; + dim3 threads2(BDIMX2, BDIMY2, 1); + constexpr int part_size = BDIMY2 * VPT; + const dim3 blocks2((feature_size + BDIMX2 - 1) / BDIMX2, part_size, 1); + + auto part_grad_gamma_ptr = + memory::Alloc(dev_ctx, part_size * feature_size * sizeof(U)); + auto part_grad_beta_ptr = + memory::Alloc(dev_ctx, part_size * feature_size * sizeof(U)); + U *part_grad_gamma = reinterpret_cast(part_grad_gamma_ptr->ptr()); + U *part_grad_beta = reinterpret_cast(part_grad_beta_ptr->ptr()); + + LayerNormBackwardPartGradGammaBeta<<>>( + d_y, x, batch_size, feature_size, mean, var, epsilon, part_grad_gamma, + part_grad_beta); // compute part_grad_gamma, beta + + constexpr int BDIMX3 = 32; + constexpr int BDIMY3 = 8; + dim3 threads3(BDIMX3, BDIMY3, 1); + const dim3 blocks3((feature_size + BDIMX2 - 1) / BDIMX2, 1, 1); + LayerNormBackwardSumGradGammaBeta< + T, U, BDIMX3, BDIMY3><<>>( + part_grad_gamma, part_grad_beta, part_size, batch_size, feature_size, + d_scale, d_bias); + + constexpr int BDIMX1 = 32; + constexpr int BDIMY1 = 4; + dim3 threads1(BDIMX1, BDIMY1, 1); + LayerNormBackwardComputeGradInput< + T, U, BDIMX1, BDIMY1><<>>( + d_y, x, batch_size, feature_size, mean, var, epsilon, scale, d_x); + break; + } + default: + break; + } +} + +} // namespace operators +} // namespace paddle diff --git a/paddle/fluid/operators/layer_norm_op.cu b/paddle/fluid/operators/layer_norm_op.cu index 6cd6a524e28..4be0c03f2de 100644 --- a/paddle/fluid/operators/layer_norm_op.cu +++ b/paddle/fluid/operators/layer_norm_op.cu @@ -12,873 +12,13 @@ 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. */ -#ifdef __NVCC__ -#include "cub/cub.cuh" -#endif -#ifdef __HIPCC__ -#include -namespace cub = hipcub; -#endif -#include -#include - -#include "paddle/fluid/framework/ddim.h" +#include "paddle/fluid/operators/layer_norm_kernel.cu.h" #include "paddle/fluid/operators/layer_norm_op.h" #include "paddle/fluid/platform/float16.h" -#ifdef PADDLE_WITH_CUDA -#include "paddle/fluid/platform/cudnn_helper.h" -#endif -#ifdef PADDLE_WITH_HIP -#include "paddle/fluid/platform/miopen_helper.h" -#endif namespace paddle { namespace operators { -using Tensor = framework::Tensor; -using DataLayout = framework::DataLayout; -template -using CudnnDataType = platform::CudnnDataType; -template -using LayerNormParamType = typename CudnnDataType::BatchNormParamType; - -inline static int GetDesiredBlockDim(int64_t block_dim) { -#ifdef __HIPCC__ - const int kMaxBlockDim = 256; - const int lwarpSize = 64; -#else - const int kMaxBlockDim = 512; - const int lwarpSize = 32; -#endif - return block_dim >= kMaxBlockDim ? kMaxBlockDim : lwarpSize; -} - -template -static __forceinline__ __device__ U WarpReduceSum(U val) { - unsigned mask = 0u; - CREATE_SHFL_MASK(mask, true); - for (int offset = warpSize / 2; offset > 0; offset /= 2) { - val += paddle::platform::CudaShuffleDownSync(mask, val, offset); - } - return val; -} - -template -__forceinline__ __device__ U BlockReduceSum(U val, U *shared) { - int lane = threadIdx.x % warpSize; - int wid = threadIdx.x / warpSize; - - val = WarpReduceSum(val); // Each warp performs partial reduction - - __syncthreads(); - if (lane == 0) shared[wid] = val; // Write reduced value to shared memory - - __syncthreads(); // Wait for all partial reductions - // read from shared memory only if that warp existed - val = - (threadIdx.x < blockDim.x / warpSize) ? shared[lane] : static_cast(0); - - if (wid == 0) val = WarpReduceSum(val); // Final reduce within first warp - - return val; -} - -#define FIXED_BLOCK_DIM_CASE_BASE(log2_block_dim, ...) \ - case (1 << (log2_block_dim)): { \ - constexpr auto kBlockDim = (1 << (log2_block_dim)); \ - __VA_ARGS__; \ - } break - -#define FIXED_BLOCK_DIM_CASE(...) \ - FIXED_BLOCK_DIM_CASE_BASE(9, ##__VA_ARGS__); \ - FIXED_BLOCK_DIM_CASE_BASE(8, ##__VA_ARGS__); \ - FIXED_BLOCK_DIM_CASE_BASE(7, ##__VA_ARGS__); \ - FIXED_BLOCK_DIM_CASE_BASE(6, ##__VA_ARGS__); \ - FIXED_BLOCK_DIM_CASE_BASE(5, ##__VA_ARGS__); \ - FIXED_BLOCK_DIM_CASE_BASE(4, ##__VA_ARGS__); \ - FIXED_BLOCK_DIM_CASE_BASE(3, ##__VA_ARGS__); \ - FIXED_BLOCK_DIM_CASE_BASE(2, ##__VA_ARGS__); \ - FIXED_BLOCK_DIM_CASE_BASE(1, ##__VA_ARGS__) - -#define FIXED_BLOCK_DIM_FIXED_BLOCK_NUM_CASE_BASE( \ - log2_block_dim, feature_size, kMaxBlockNum, ...) \ - case (1 << (log2_block_dim)): { \ - for (int64_t i = 0; i < std::ceil(feature_size / (1.0 * kMaxBlockNum)); \ - i++) { \ - int64_t col_offset = i * static_cast(kMaxBlockNum); \ - int block_num = static_cast(std::min( \ - feature_size - col_offset, static_cast(kMaxBlockNum))); \ - constexpr auto kBlockDim = (1 << (log2_block_dim)); \ - __VA_ARGS__; \ - } \ - } break - -#define FIXED_BLOCK_DIM_FIXED_BLOCK_NUM_CASE(feature_size, kMaxBlockNum, ...) \ - FIXED_BLOCK_DIM_FIXED_BLOCK_NUM_CASE_BASE(9, feature_size, kMaxBlockNum, \ - ##__VA_ARGS__); \ - FIXED_BLOCK_DIM_FIXED_BLOCK_NUM_CASE_BASE(8, feature_size, kMaxBlockNum, \ - ##__VA_ARGS__); \ - FIXED_BLOCK_DIM_FIXED_BLOCK_NUM_CASE_BASE(7, feature_size, kMaxBlockNum, \ - ##__VA_ARGS__); \ - FIXED_BLOCK_DIM_FIXED_BLOCK_NUM_CASE_BASE(6, feature_size, kMaxBlockNum, \ - ##__VA_ARGS__); \ - FIXED_BLOCK_DIM_FIXED_BLOCK_NUM_CASE_BASE(5, feature_size, kMaxBlockNum, \ - ##__VA_ARGS__); \ - FIXED_BLOCK_DIM_FIXED_BLOCK_NUM_CASE_BASE(4, feature_size, kMaxBlockNum, \ - ##__VA_ARGS__); \ - FIXED_BLOCK_DIM_FIXED_BLOCK_NUM_CASE_BASE(3, feature_size, kMaxBlockNum, \ - ##__VA_ARGS__); \ - FIXED_BLOCK_DIM_FIXED_BLOCK_NUM_CASE_BASE(2, feature_size, kMaxBlockNum, \ - ##__VA_ARGS__); \ - FIXED_BLOCK_DIM_FIXED_BLOCK_NUM_CASE_BASE(1, feature_size, kMaxBlockNum, \ - ##__VA_ARGS__) - -static __device__ __forceinline__ float real_sqrt(float x) { return sqrtf(x); } -static __device__ __forceinline__ double real_sqrt(double x) { return sqrt(x); } - -template -struct PairForLayerNorm { - __device__ __forceinline__ PairForLayerNorm() {} - __device__ __forceinline__ PairForLayerNorm(const T &first, const T &second) - : first_(first), second_(second) {} - - T first_; - T second_; -}; - -template -struct PairForLayerNormAddFunctor { - __device__ __forceinline__ PairForLayerNorm operator()( - const PairForLayerNorm &p1, const PairForLayerNorm &p2) { - return PairForLayerNorm(p1.first_ + p2.first_, p1.second_ + p2.second_); - } -}; - -template -__inline__ __device__ T rsqrt_(const T val) { - return static_cast(1) / sqrt(val); -} - -template <> -__inline__ __device__ float rsqrt_(const float val) { - return rsqrtf(val); -} - -template <> -__inline__ __device__ double rsqrt_(const double val) { - return rsqrt(val); -} - -#if CUDA_ARCH_FP16_SUPPORTED(__CUDA_ARCH__) -template <> -__inline__ __device__ half rsqrt_(const half val) { - return hrsqrt(val); -} -#endif - -template -__global__ void LayerNormForward(const T *x, const U *scale, const U *bias, - T *y, U *mean, U *var, float epsilon, - int64_t feature_size) { - __shared__ U mean_share; - __shared__ U var_share; - __shared__ U shared_mean[32]; // threadIdx.x / warpSize <= kMaxBlockDim / - // warpSize <= 1024/32 = 32; - __shared__ U shared_var[32]; - - int64_t beg_idx = blockIdx.x * feature_size + threadIdx.x; - int64_t end_idx = (blockIdx.x + 1) * feature_size; - - // Step 1: Reduce to calculate mean and var - U mean_val = 0; - U var_val = 0; - for (int64_t i = beg_idx; i < end_idx; i += BlockDim) { - U tmp = static_cast(x[i]); - mean_val += tmp; - var_val += (tmp * tmp); - } - - mean_val = BlockReduceSum(mean_val, shared_mean); - var_val = BlockReduceSum(var_val, shared_var); - - if (threadIdx.x == 0) { - auto scale = static_cast(1.) / static_cast(feature_size); - auto tmp = mean_val * scale; - mean[blockIdx.x] = mean_share = static_cast(tmp); - var_share = static_cast(var_val * scale - mean_share * mean_share); - var_share = var_share > U(0) ? var_share : U(0); - var[blockIdx.x] = var_share; - } - __syncthreads(); - - mean_val = mean_share; - U invvar = rsqrt_(var_share + static_cast(epsilon)); - - // Step 2: Calculate y - if (scale != nullptr) { - if (bias != nullptr) { - for (int64_t i = beg_idx, j = threadIdx.x; i < end_idx; - i += BlockDim, j += BlockDim) { - y[i] = static_cast( - scale[j] * (static_cast(x[i]) - mean_val) * invvar + bias[j]); - } - } else { - for (int64_t i = beg_idx, j = threadIdx.x; i < end_idx; - i += BlockDim, j += BlockDim) { - y[i] = static_cast(scale[j] * (static_cast(x[i]) - mean_val) * - invvar); - } - } - } else { // scale == nullptr - if (bias != nullptr) { - for (int64_t i = beg_idx, j = threadIdx.x; i < end_idx; - i += BlockDim, j += BlockDim) { - y[i] = static_cast((static_cast(x[i]) - mean_val) * invvar + - bias[j]); - } - } else { - for (int64_t i = beg_idx, j = threadIdx.x; i < end_idx; - i += BlockDim, j += BlockDim) { - y[i] = static_cast((static_cast(x[i]) - mean_val) * invvar); - } - } - } -} - -template -__inline__ __device__ void cuLoadAddStridedInputs( - const int64_t i1_block, const int thr_load_row_off, - const int thr_load_col_off, const int i2_off, const int row_stride, - U *warp_buf1, U *warp_buf2, const T *input, const T *dout, - const int64_t i1_end, const int64_t n2, const U *__restrict__ mean, - const U *__restrict__ var, const float epsilon) { - const int64_t i1 = i1_block + thr_load_row_off; - if (i1 >= i1_end) return; - U curr_mean = mean[i1]; - U curr_invvar = rsqrt_(var[i1] + epsilon); - for (int k = 0; k < VPT; ++k) { - const int i2 = i2_off + k; - const int64_t load_idx = i1 * n2 + i2; - const int write_idx = thr_load_row_off * row_stride + thr_load_col_off + k; - if (i2 < n2) { - U curr_input = static_cast(input[load_idx]); - U curr_dout = static_cast(dout[load_idx]); - warp_buf1[write_idx] += curr_dout; - warp_buf2[write_idx] += - curr_dout * (curr_input - curr_mean) * curr_invvar; - } - } -} - -template -__global__ void LayerNormBackwardPartGradGammaBeta( - const T *__restrict__ dout, const T *__restrict__ input, const int64_t n1, - const int64_t n2, const U *__restrict__ mean, const U *__restrict__ var, - float epsilon, U *part_grad_gamma, U *part_grad_beta) { - // VPTX -> value per thread.x, BDIMX -> blockDim.x, BDIMY -> blockDim.y, BDIMX - // -> blockDim.x - // template for compile time optimizations - - constexpr int row_stride = BDIMX + 1; - const int thr_load_col_off = (threadIdx.x * VPTX) & (BDIMX - 1); - const int thr_load_row_off = - (threadIdx.x * VPTX) / BDIMX + threadIdx.y * BDIMY; - const int i2_off = blockIdx.x * BDIMX + thr_load_col_off; - - constexpr int shared_cap = (BDIMX * BDIMY > 2 * VPTX * BDIMY * row_stride) - ? BDIMX * BDIMY - : 2 * VPTX * BDIMY * row_stride; - __shared__ U buf[shared_cap]; - - U *warp_buf1 = reinterpret_cast(buf); - U *warp_buf2 = warp_buf1 + VPTX * BDIMY * row_stride; - - for (int idx = threadIdx.y * blockDim.x + threadIdx.x; - idx < 2 * VPTX * BDIMY * row_stride; idx += BDIMX * BDIMY) { - buf[idx] = U(0); - } - __syncthreads(); - - for (int64_t i1_block = blockIdx.y * BDIMY * VPTX; i1_block < n1; - i1_block += VPTX * BDIMY * gridDim.y) { - cuLoadAddStridedInputs( - i1_block, thr_load_row_off, thr_load_col_off, i2_off, row_stride, - warp_buf1, warp_buf2, input, dout, n1, n2, mean, var, epsilon); - } - __syncthreads(); - - // inter-warp reductions - // sum within each warp - U acc1 = U(0); - U acc2 = U(0); - for (int k = 0; k < VPTX; ++k) { - int row1 = threadIdx.y + k * VPTX; - int idx1 = row1 * row_stride + threadIdx.x; - acc1 += warp_buf1[idx1]; - acc2 += warp_buf2[idx1]; - } - warp_buf1[threadIdx.y * row_stride + threadIdx.x] = acc1; - warp_buf2[threadIdx.y * row_stride + threadIdx.x] = acc2; - __syncthreads(); - // sum all warps - for (int offset = VPTX >> 1; offset > 1; offset >>= 1) { - if (threadIdx.y < offset) { - int row1 = threadIdx.y; - int row2 = threadIdx.y + offset; - int idx1 = row1 * row_stride + threadIdx.x; - int idx2 = row2 * row_stride + threadIdx.x; - warp_buf1[idx1] += warp_buf1[idx2]; - warp_buf2[idx1] += warp_buf2[idx2]; - } - __syncthreads(); - } - int64_t i2 = blockIdx.x * blockDim.x + threadIdx.x; - if (threadIdx.y == 0 && i2 < n2) { - int row1 = threadIdx.y; - int row2 = threadIdx.y + 1; - int idx1 = row1 * row_stride + threadIdx.x; - int idx2 = row2 * row_stride + threadIdx.x; - part_grad_beta[blockIdx.y * n2 + i2] = warp_buf1[idx1] + warp_buf1[idx2]; - part_grad_gamma[blockIdx.y * n2 + i2] = warp_buf2[idx1] + warp_buf2[idx2]; - } -} - -template -__global__ void LayerNormBackwardSumGradGammaBeta( - const U *part_grad_gamma, const U *part_grad_beta, const int part_size, - // const int n1, const int n2, T* grad_gamma, T* grad_beta) { - const int n1, const int n2, U *grad_gamma, U *grad_beta) { - // sum partial gradients for gamma and beta - __shared__ U buf[BDIMX * BDIMY]; - int64_t i2 = blockIdx.x * BDIMX + threadIdx.x; - if (i2 < n2) { - // each warp does sequential reductions until reduced part_size is num_warps - int num_warp_reductions = part_size / BDIMY; - U sum_gamma = U(0); - U sum_beta = U(0); - const U *part_grad_gamma_ptr = - part_grad_gamma + threadIdx.y * num_warp_reductions * n2 + i2; - const U *part_grad_beta_ptr = - part_grad_beta + threadIdx.y * num_warp_reductions * n2 + i2; - for (int warp_offset = 0; warp_offset < num_warp_reductions; - ++warp_offset) { - sum_gamma += part_grad_gamma_ptr[warp_offset * n2]; - sum_beta += part_grad_beta_ptr[warp_offset * n2]; - } - // inter-warp reductions - constexpr int nbsize3 = BDIMX * BDIMY / 2; - for (int offset = BDIMY / 2; offset >= 1; offset /= 2) { - // top half write to shared memory - if (threadIdx.y >= offset && threadIdx.y < 2 * offset) { - const int write_idx = (threadIdx.y - offset) * blockDim.x + threadIdx.x; - buf[write_idx] = sum_gamma; - buf[write_idx + nbsize3] = sum_beta; - } - __syncthreads(); - // bottom half sums - if (threadIdx.y < offset) { - const int read_idx = threadIdx.y * BDIMX + threadIdx.x; - sum_gamma += buf[read_idx]; - sum_beta += buf[read_idx + nbsize3]; - } - __syncthreads(); - } - // write out fully summed gradients - if (threadIdx.y == 0) { - grad_gamma[i2] = sum_gamma; - grad_beta[i2] = sum_beta; - } - } -} - -template -__global__ void LayerNormBackwardComputeGradInput( - const T *__restrict__ dout, const T *__restrict__ input, const int n1, - const int n2, - // const U* __restrict__ mean, const U* __restrict__ var, const float - // epsilon, const T* gamma, - const U *__restrict__ mean, const U *__restrict__ var, const float epsilon, - const U *gamma, T *grad_input) { -#ifdef __HIPCC__ - for (auto i1 = hipBlockIdx_x; i1 < n1; i1 += hipGridDim_x) { -#else - for (auto i1 = blockIdx.x; i1 < n1; i1 += gridDim.x) { -#endif - U sum_loss1 = U(0); - U sum_loss2 = U(0); - const U c_mean = mean[i1]; - const U c_invvar = rsqrt_(var[i1] + epsilon); - const T *k_input = input + i1 * n2; - const T *k_dout = dout + i1 * n2; - constexpr int numx = BDIMX * BDIMY; - const int thrx = threadIdx.x + threadIdx.y * BDIMX; - if (gamma != NULL) { - int l = 4 * thrx; - for (; l + 3 < n2; l += 4 * numx) { - for (int k = 0; k < 4; ++k) { - const U c_h = static_cast(k_input[l + k]); - const U c_loss = static_cast(k_dout[l + k]); - sum_loss1 += c_loss * gamma[l + k]; - sum_loss2 += c_loss * gamma[l + k] * (c_h - c_mean) * c_invvar; - } - } - for (; l < n2; ++l) { - const U c_h = static_cast(k_input[l]); - const U c_loss = static_cast(k_dout[l]); - sum_loss1 += c_loss * gamma[l]; - sum_loss2 += c_loss * gamma[l] * (c_h - c_mean) * c_invvar; - } - } else { - int l = 4 * thrx; - for (; l + 3 < n2; l += 4 * numx) { - for (int k = 0; k < 4; ++k) { - const U c_h = static_cast(k_input[l + k]); - const U c_loss = static_cast(k_dout[l + k]); - sum_loss1 += c_loss; - sum_loss2 += c_loss * (c_h - c_mean) * c_invvar; - } - } - for (; l < n2; ++l) { - const U c_h = static_cast(k_input[l]); - const U c_loss = static_cast(k_dout[l]); - sum_loss1 += c_loss; - sum_loss2 += c_loss * (c_h - c_mean) * c_invvar; - } - } - // intra-warp reductions - for (int mask = BDIMX / 2; mask > 0; mask /= 2) { -#ifdef PADDLE_WITH_HIP - sum_loss1 += __shfl_xor(sum_loss1, mask, - warpSize); // WARP_SHFL_XOR(sum_loss1, mask); - sum_loss2 += __shfl_xor(sum_loss2, mask, - warpSize); // WARP_SHFL_XOR(sum_loss2, mask); -#else - sum_loss1 += - __shfl_xor_sync(0xffffffff, sum_loss1, mask, - warpSize); // WARP_SHFL_XOR(sum_loss1, mask); - sum_loss2 += - __shfl_xor_sync(0xffffffff, sum_loss2, mask, - warpSize); // WARP_SHFL_XOR(sum_loss2, mask); -#endif - } - // inter-warp reductions - if (BDIMY > 1) { - __shared__ U buf[BDIMX * BDIMY]; - for (int offset = BDIMY / 2; offset > 0; offset /= 2) { - // upper half of warps write to shared - if (threadIdx.y >= offset && threadIdx.y < 2 * offset) { - const int wrt_i = (threadIdx.y - offset) * BDIMX + threadIdx.x; - buf[2 * wrt_i] = sum_loss1; - buf[2 * wrt_i + 1] = sum_loss2; - } - __syncthreads(); - // lower half merges - if (threadIdx.y < offset) { - const int read_i = threadIdx.y * blockDim.x + threadIdx.x; - sum_loss1 += buf[2 * read_i]; - sum_loss2 += buf[2 * read_i + 1]; - } - __syncthreads(); - } - if (threadIdx.y == 0) { - buf[2 * threadIdx.x] = sum_loss1; - buf[2 * threadIdx.x + 1] = sum_loss2; - } - __syncthreads(); - if (threadIdx.y != 0) { - sum_loss1 = buf[2 * threadIdx.x]; - sum_loss2 = buf[2 * threadIdx.x + 1]; - } - } - // all threads now have the two sums over l - U fH = (U)n2; - U term1 = (U(1) / fH) * c_invvar; - T *k_grad_input = grad_input + i1 * n2; - if (gamma != NULL) { - for (int l = thrx; l < n2; l += numx) { - const U c_h = static_cast(k_input[l]); - const U c_loss = static_cast(k_dout[l]); - U f_grad_input = fH * c_loss * gamma[l]; - f_grad_input -= sum_loss1; - f_grad_input -= (c_h - c_mean) * c_invvar * sum_loss2; - f_grad_input *= term1; - k_grad_input[l] = static_cast(f_grad_input); - } - } else { - for (int l = thrx; l < n2; l += numx) { - const U c_h = static_cast(k_input[l]); - const U c_loss = static_cast(k_dout[l]); - U f_grad_input = fH * c_loss; - f_grad_input -= sum_loss1; - f_grad_input -= (c_h - c_mean) * c_invvar * sum_loss2; - f_grad_input *= term1; - k_grad_input[l] = static_cast(f_grad_input); - } - } - } -} - -// Make sure that d_scale != nullptr && d_bias != nullptr -// Since d_scale != nullptr, scale would not be nullptr -template -__global__ void LayerNormBackwardGradientAll( - const T *x, const T *d_y, U *d_scale, U *d_bias, T *d_x, const U *mean, - const U *var, const U *scale, float epsilon, int64_t batch_size, - int64_t feature_size, int64_t col_offset) { - int64_t beg_idx = threadIdx.x * feature_size + (blockIdx.x + col_offset); - int64_t end_idx = batch_size * feature_size + (blockIdx.x + col_offset); - int64_t stride = BlockDim * feature_size; - - U d_scale_partial = static_cast(0), d_bias_partial = static_cast(0); - - for (int64_t i = beg_idx; i < end_idx; i += stride) { - int row_idx = i / feature_size; - auto var_val = real_sqrt(static_cast(var[row_idx]) + epsilon); - d_scale_partial += static_cast(d_y[i]) * - (static_cast(x[i]) - mean[row_idx]) / var_val; - d_bias_partial += static_cast(d_y[i]); - if (HasDx) { - d_x[i] = static_cast(static_cast(d_y[i]) * - scale[blockIdx.x + col_offset] / var_val); - } - } - - __shared__ U shared_scale[32]; // threadIdx.x / warpSize <= kMaxBlockDim / - // warpSize <= 1024/32 = 32; - __shared__ U shared_bias[32]; - d_scale_partial = BlockReduceSum(d_scale_partial, shared_scale); - d_bias_partial = BlockReduceSum(d_bias_partial, shared_bias); - - if (threadIdx.x == 0) { - d_scale[blockIdx.x + col_offset] = d_scale_partial; - d_bias[blockIdx.x + col_offset] = d_bias_partial; - } -} - -// Make sure that there is only one true expression: d_scale != nullptr -// or d_bias != nullptr -// Notice: scale may be nullptr -template -__global__ void LayerNormBackwardGradientScaleOrBias( - const T *x, const T *d_y, U *d_scale, U *d_bias, T *d_x, const U *mean, - const U *var, const U *scale, float epsilon, int64_t batch_size, - int64_t feature_size, int col_offset) { - using BlockReduce = cub::BlockReduce; - __shared__ typename BlockReduce::TempStorage temp_storage; - int64_t beg_idx = threadIdx.x * feature_size + blockIdx.x + col_offset; - int64_t end_idx = batch_size * feature_size + blockIdx.x + col_offset; - int stride = BlockDim * feature_size; - U d_scale_or_d_bias_partial = static_cast(0); - - for (int64_t i = beg_idx; i < end_idx; i += stride) { - int row_idx = i / feature_size; - auto var_val = - static_cast(real_sqrt(static_cast(var[row_idx]) + epsilon)); - if (HasDScale) { - d_scale_or_d_bias_partial += static_cast(d_y[i]) * - (static_cast(x[i]) - mean[row_idx]) / - var_val; - } else { // d_bias != nullptr - d_scale_or_d_bias_partial += static_cast(d_y[i]); - } - - if (HasDx) { - if (scale != nullptr) { - d_x[i] = static_cast(static_cast(d_y[i]) * - scale[blockIdx.x + col_offset] / var_val); - } else { - d_x[i] = static_cast(static_cast(d_y[i]) / var_val); - } - } - } - - d_scale_or_d_bias_partial = - BlockReduce(temp_storage).Reduce(d_scale_or_d_bias_partial, cub::Sum()); - - if (threadIdx.x == 0) { - if (HasDScale) { - d_scale[blockIdx.x + col_offset] = d_scale_or_d_bias_partial; - } else { - d_bias[blockIdx.x + col_offset] = d_scale_or_d_bias_partial; - } - } -} - -template -__global__ void LayerNormBackwardPostProcessToCalculateDX( - const T *x, T *d_x, const U *mean, const U *var, float epsilon, - int64_t feature_size) { - using BlockReduce = cub::BlockReduce, BlockDim>; - __shared__ typename BlockReduce::TempStorage temp_storage; - __shared__ U d_x_reduce_tmp[2]; - - int64_t beg_idx = blockIdx.x * feature_size + threadIdx.x; - int64_t end_idx = (blockIdx.x + 1) * feature_size; - - U block_mean = mean[blockIdx.x]; - U block_var = var[blockIdx.x]; - U d_x_mean_partial = static_cast(0), d_x_var_partial = static_cast(0); - for (int64_t i = beg_idx; i < end_idx; i += BlockDim) { - d_x_mean_partial += static_cast(d_x[i]); - d_x_var_partial += - static_cast(d_x[i]) * (static_cast(x[i]) - block_mean); - } - - auto pair = - BlockReduce(temp_storage) - .Reduce(PairForLayerNorm(d_x_mean_partial, d_x_var_partial), - PairForLayerNormAddFunctor()); - - if (threadIdx.x == 0) { - d_x_reduce_tmp[0] = static_cast(pair.first_) / feature_size; - d_x_reduce_tmp[1] = - static_cast(pair.second_) / - (feature_size * (static_cast(block_var) + epsilon)); - } - __syncthreads(); - - d_x_mean_partial = d_x_reduce_tmp[0]; - d_x_var_partial = d_x_reduce_tmp[1]; - for (int64_t i = beg_idx; i < end_idx; i += BlockDim) { - d_x[i] -= static_cast(d_x_mean_partial); - d_x[i] -= - static_cast((static_cast(x[i]) - block_mean) * d_x_var_partial); - } -} - -// Here, we only calculate d_x -template -__global__ void LayerNormBackwardGradientOnlyDX(const T *x, const T *d_y, - T *d_x, const U *mean, - const U *var, const U *scale, - float epsilon, - int64_t feature_size) { - using BlockReduce = cub::BlockReduce, BlockDim>; - __shared__ typename BlockReduce::TempStorage temp_storage; - __shared__ U d_x_reduce_tmp[2]; - - int64_t beg_idx = blockIdx.x * feature_size + threadIdx.x; - int64_t end_idx = (blockIdx.x + 1) * feature_size; - - U block_mean = mean[blockIdx.x], block_var = var[blockIdx.x]; - U d_x_mean_partial = static_cast(0), d_x_var_partial = static_cast(0); - for (int64_t i = beg_idx; i < end_idx; i += BlockDim) { - auto var_val = - static_cast(real_sqrt(static_cast(block_var) + epsilon)); - if (scale != nullptr) { - int col_idx = i % feature_size; - d_x[i] = - static_cast(static_cast(d_y[i]) * scale[col_idx] / var_val); - } else { - d_x[i] = static_cast(static_cast(d_y[i]) / var_val); - } - d_x_mean_partial += static_cast(d_x[i]); - d_x_var_partial += - static_cast(d_x[i]) * (static_cast(x[i]) - block_mean); - } - - auto pair = - BlockReduce(temp_storage) - .Reduce(PairForLayerNorm(d_x_mean_partial, d_x_var_partial), - PairForLayerNormAddFunctor()); - - if (threadIdx.x == 0) { - d_x_reduce_tmp[0] = static_cast(pair.first_) / feature_size; - d_x_reduce_tmp[1] = - static_cast(pair.second_) / - (feature_size * (static_cast(block_var) + epsilon)); - } - __syncthreads(); - - d_x_mean_partial = d_x_reduce_tmp[0]; - d_x_var_partial = d_x_reduce_tmp[1]; - for (int64_t i = beg_idx; i < end_idx; i += BlockDim) { - d_x[i] -= static_cast(d_x_mean_partial); - d_x[i] -= - static_cast((static_cast(x[i]) - block_mean) * d_x_var_partial); - } -} - -template -__global__ void LayerNormBackwardWhenBatchSizeIsOne( - const T *x, const T *d_y, T *d_x, U *d_scale, U *d_bias, const U *mean, - const U *var, const U *scale, float epsilon, int64_t feature_size) { - int64_t idx = threadIdx.x + blockIdx.x * blockDim.x; - if (idx < feature_size) { - auto var_val = - static_cast(real_sqrt(static_cast(var[idx]) + epsilon)); - if (d_x != nullptr) { - if (d_scale == nullptr) { - d_x[idx] = static_cast(static_cast(d_y[idx]) / var_val); - } else { - d_x[idx] = - static_cast(static_cast(d_y[idx]) * scale[idx] / var_val); - } - } - - if (d_scale != nullptr) { - d_scale[idx] = static_cast(d_y[idx]) * - (static_cast(x[idx]) - mean[idx]) / var_val; - } - - if (d_bias != nullptr) d_bias[idx] = static_cast(d_y[idx]); - } -} - -template -static void LayerNormBackward(const T *x, const T *d_y, const U *scale, - const U *mean, const U *var, T *d_x, U *d_scale, - U *d_bias, float epsilon, int64_t batch_size, - int64_t feature_size, - const framework::ExecutionContext &ctx) { - auto &dev_ctx = ctx.cuda_device_context(); - auto stream = dev_ctx.stream(); -#ifdef __HIPCC__ - const int kMaxBlockDim = 256; -#else - const int kMaxBlockDim = 512; -#endif - const int kMaxBlockNum = 128; - int gradient_flag = ((d_x != nullptr ? 1 : 0) << 2) | - ((d_scale != nullptr ? 1 : 0) << 1) | - ((d_bias != nullptr ? 1 : 0)); - if (gradient_flag == 0) return; - - if (batch_size == 1) { - LayerNormBackwardWhenBatchSizeIsOne< - T, U><<<(feature_size + kMaxBlockDim - 1) / kMaxBlockDim, kMaxBlockDim, - 0, stream>>>(x, d_y, d_x, d_scale, d_bias, mean, var, scale, - epsilon, feature_size); - - if (d_x != nullptr) { - switch (GetDesiredBlockDim(feature_size)) { - FIXED_BLOCK_DIM_CASE(LayerNormBackwardPostProcessToCalculateDX< - T, U, kBlockDim><<<1, kBlockDim, 0, stream>>>( - x, d_x, mean, var, epsilon, feature_size)); - } - } - return; - } - - auto block_dim = GetDesiredBlockDim(batch_size); - switch (gradient_flag) { - case 1: // d_x == nulptr, d_scale == nullptr, d_bias != nullptr - switch (block_dim) { - FIXED_BLOCK_DIM_FIXED_BLOCK_NUM_CASE( - feature_size, kMaxBlockNum, - LayerNormBackwardGradientScaleOrBias< - T, U, kBlockDim, false, - false><<>>( - x, d_y, d_scale, d_bias, d_x, mean, var, scale, epsilon, - batch_size, feature_size, col_offset)); - } - break; - case 2: // d_x == nullptr, d_scale != nullptr, d_bias == nullptr - switch (block_dim) { - FIXED_BLOCK_DIM_FIXED_BLOCK_NUM_CASE( - feature_size, kMaxBlockNum, - LayerNormBackwardGradientScaleOrBias< - T, U, kBlockDim, false, - true><<>>( - x, d_y, d_scale, d_bias, d_x, mean, var, scale, epsilon, - batch_size, feature_size, col_offset)); - } - break; - case 3: // d_x == nullptr, d_scale != nulptr, d_bias != nullptr - switch (block_dim) { - FIXED_BLOCK_DIM_FIXED_BLOCK_NUM_CASE( - feature_size, kMaxBlockNum, - LayerNormBackwardGradientAll< - T, U, kBlockDim, false><<>>( - x, d_y, d_scale, d_bias, d_x, mean, var, scale, epsilon, - batch_size, feature_size, col_offset)); - } - break; - case 4: // d_x != nullptr, d_scale == nullptr, d_bias == nullptr - switch (GetDesiredBlockDim(feature_size)) { - FIXED_BLOCK_DIM_CASE( - LayerNormBackwardGradientOnlyDX< - T, U, kBlockDim><<>>( - x, d_y, d_x, mean, var, scale, epsilon, feature_size)); - } - break; - case 5: // d_x != nulptr, d_scale == nullptr, d_bias != nullptr - switch (block_dim) { - FIXED_BLOCK_DIM_FIXED_BLOCK_NUM_CASE( - feature_size, kMaxBlockNum, - LayerNormBackwardGradientScaleOrBias< - T, U, kBlockDim, true, - false><<>>( - x, d_y, d_scale, d_bias, d_x, mean, var, scale, epsilon, - batch_size, feature_size, col_offset)); - } - switch (GetDesiredBlockDim(feature_size)) { - FIXED_BLOCK_DIM_CASE( - LayerNormBackwardPostProcessToCalculateDX< - T, U, kBlockDim><<>>( - x, d_x, mean, var, epsilon, feature_size)); - } - break; - case 6: // d_x != nullptr, d_scale != nullptr, d_bias == nullptr - switch (block_dim) { - FIXED_BLOCK_DIM_FIXED_BLOCK_NUM_CASE( - feature_size, kMaxBlockNum, - LayerNormBackwardGradientScaleOrBias< - T, U, kBlockDim, true, - true><<>>( - x, d_y, d_scale, d_bias, d_x, mean, var, scale, epsilon, - batch_size, feature_size, col_offset)); - } - switch (GetDesiredBlockDim(feature_size)) { - FIXED_BLOCK_DIM_CASE( - LayerNormBackwardPostProcessToCalculateDX< - T, U, kBlockDim><<>>( - x, d_x, mean, var, epsilon, feature_size)); - } - break; - case 7: // d_x != nullptr, d_scale != nullptr, d_bias != nullptr - { - constexpr int VPT = 4; - constexpr int BDIMX2 = 32; - constexpr int BDIMY2 = 4; - dim3 threads2(BDIMX2, BDIMY2, 1); - constexpr int part_size = BDIMY2 * VPT; - const dim3 blocks2((feature_size + BDIMX2 - 1) / BDIMX2, part_size, 1); - - auto part_grad_gamma_ptr = - memory::Alloc(dev_ctx, part_size * feature_size * sizeof(U)); - auto part_grad_beta_ptr = - memory::Alloc(dev_ctx, part_size * feature_size * sizeof(U)); - U *part_grad_gamma = reinterpret_cast(part_grad_gamma_ptr->ptr()); - U *part_grad_beta = reinterpret_cast(part_grad_beta_ptr->ptr()); - - LayerNormBackwardPartGradGammaBeta<<>>( - d_y, x, batch_size, feature_size, mean, var, epsilon, part_grad_gamma, - part_grad_beta); // compute part_grad_gamma, beta - - constexpr int BDIMX3 = 32; - constexpr int BDIMY3 = 8; - dim3 threads3(BDIMX3, BDIMY3, 1); - const dim3 blocks3((feature_size + BDIMX2 - 1) / BDIMX2, 1, 1); - LayerNormBackwardSumGradGammaBeta< - T, U, BDIMX3, BDIMY3><<>>( - part_grad_gamma, part_grad_beta, part_size, batch_size, feature_size, - d_scale, d_bias); - - constexpr int BDIMX1 = 32; - constexpr int BDIMY1 = 4; - dim3 threads1(BDIMX1, BDIMY1, 1); - LayerNormBackwardComputeGradInput< - T, U, BDIMX1, BDIMY1><<>>( - d_y, x, batch_size, feature_size, mean, var, epsilon, scale, d_x); - break; - } - default: - break; - } -} - template void LayerNormDirectCUDAFunctor::operator()(gpuStream_t stream, const T *input, @@ -986,16 +126,12 @@ class LayerNormGradKernel LayerNormBackward(x_data, d_y_data, scale_data, mean_data, var_data, d_x_data, d_scale_data, d_bias_data, epsilon, - batch_size, feature_size, ctx); + batch_size, feature_size, + ctx.cuda_device_context()); } }; template class LayerNormDirectCUDAFunctor; - -#undef FIXED_BLOCK_DIM_FIXED_BLOCK_NUM_CASE_BASE -#undef FIXED_BLOCK_DIM_FIXED_BLOCK_NUM_CASE -#undef FIXED_BLOCK_DIM_CASE_BASE -#undef FIXED_BLOCK_DIM_CASE } // namespace operators } // namespace paddle -- GitLab