BatchNorm backward implementation (#461)

* Implemented batchnorm-backward Blockwise and Multiblock kernels

* Add batchnorm-backward device op

* Add batchnorm-backward host-reference op

* Add batchnorm-backward example

* Parameters renaming in batchnorm backward kernels and device op

* Change in the example to loose the threshold for ScaleDiff checking

* Add comments to explain the implementation of batchnorm-backward

* Parameters renaming again in batchnorm backward kernels

* Improve the expression calculation for performance

* Add batchnorm backward to README

* Add comments to explain inv-variance in batchnorm forward and backward

* Renaming the batchnorm forward training and inferring examples

* Add/update the comments for batchnorm-backward kernels

* Renaming again

* Add block_sync_lds between two consecutive blockwise reductions

* Move common expression 1/N out of the static_for loops

* Add dy_elementwise_op

* Renaming in backward example again

* Add checking for reduceDims in reference_batchnorm_backward

* Update to comments and codes format

* Rename in the comments

* Remove common expression out of the loop in reference_batchnorm_backward_nhwc_c

* Add block_sync_lds() between blockwise reduction again

* Fix comments again

* Remove int8 from batchnorm-forward instances since it is not needed for forward training and could fail test

[ROCm/composable_kernel commit: 44789d992a]
This commit is contained in:
Qianfeng
2022-11-29 10:51:10 +08:00
committed by GitHub
parent b3d1f5f23e
commit 0ef7876035
15 changed files with 3710 additions and 2 deletions

View File

@@ -0,0 +1,319 @@
// SPDX-License-Identifier: MIT
// Copyright (c) 2018-2022, Advanced Micro Devices, Inc. All rights reserved.
#pragma once
#include <iostream>
#include <sstream>
#include <algorithm>
#include "ck/tensor_operation/gpu/device/device_batchnorm_backward.hpp"
namespace ck {
namespace tensor_operation {
namespace host {
template <typename XDataType,
typename DyDataType,
typename DxDataType,
typename AccDataType,
typename ScaleDataType,
typename BiasDataType,
typename MeanVarDataType,
typename DyElementwiseOp>
struct ReferenceBatchNormBwd_Input_N_H_W_C_Output_C
: public device::DeviceBatchNormBwd<4, 3, DyElementwiseOp>
{
struct Argument : public device::BaseArgument
{
Argument(const std::array<index_t, 4> xyLengths,
const std::array<index_t, 4> xStrides,
const std::array<index_t, 4> dyStrides,
const std::array<index_t, 4> dxStrides,
const std::array<int, 3> reduceDims,
const std::array<ck::index_t, 1> bnScaleBiasMeanVarLengths,
const std::array<ck::index_t, 1> bnScaleStrides,
const std::array<ck::index_t, 1> bnBiasStrides,
const std::array<ck::index_t, 1> bnMeanVarStrides,
const XDataType* p_x,
const DyDataType* p_dy,
const ScaleDataType* p_scale,
const MeanVarDataType* p_savedMean,
const MeanVarDataType* p_savedInvVar,
double epsilon,
const DyElementwiseOp dy_elementwise_op,
DxDataType* p_dx,
ScaleDataType* p_dscale,
BiasDataType* p_dbias)
: p_x_(p_x),
p_dy_(p_dy),
p_scale_(p_scale),
p_savedMean_(p_savedMean),
p_savedInvVar_(p_savedInvVar),
epsilon_(epsilon),
dy_elementwise_op_(dy_elementwise_op),
p_dx_(p_dx),
p_dscale_(p_dscale),
p_dbias_(p_dbias)
{
ignore = xStrides;
ignore = dyStrides;
ignore = dxStrides;
ignore = bnScaleStrides;
ignore = bnBiasStrides;
ignore = bnMeanVarStrides;
if(xyLengths.size() != 4 || bnScaleBiasMeanVarLengths.size() != 1 ||
bnScaleBiasMeanVarLengths[0] != xyLengths[3])
throw std::runtime_error("Invalid tensor dimensions!");
if(reduceDims[0] != 0 || reduceDims[1] != 1 || reduceDims[2] != 2)
throw std::runtime_error("Invalid reduce dimensions!");
n_ = xyLengths[0];
h_ = xyLengths[1];
w_ = xyLengths[2];
c_ = xyLengths[3];
haveSavedMeanInvVar_ = (p_savedMean != nullptr && p_savedInvVar != nullptr);
}
const XDataType* p_x_;
const DyDataType* p_dy_;
const ScaleDataType* p_scale_;
const MeanVarDataType* p_savedMean_;
const MeanVarDataType* p_savedInvVar_;
double epsilon_;
const DyElementwiseOp dy_elementwise_op_;
DxDataType* p_dx_;
ScaleDataType* p_dscale_;
BiasDataType* p_dbias_;
bool haveSavedMeanInvVar_;
index_t n_, h_, w_, c_;
};
struct Invoker : public device::BaseInvoker
{
float Run(const Argument& arg)
{
auto thread_reduce_func = [&](auto iC) {
AccDataType reduceSize = type_convert<AccDataType>(arg.n_) *
type_convert<AccDataType>(arg.h_) *
type_convert<AccDataType>(arg.w_);
index_t offset_C = iC;
AccDataType mean;
AccDataType invVar;
if(arg.haveSavedMeanInvVar_)
{
mean = arg.p_savedMean_[offset_C];
invVar = arg.p_savedInvVar_[offset_C];
}
else
{
AccDataType meansquare;
meansquare = type_convert<AccDataType>(0.0f);
mean = type_convert<AccDataType>(0.0f);
// compute mean, meanquare, variance, inv-variance
for(index_t iN = 0; iN < arg.n_; iN++)
{
index_t offset_N = iN * arg.h_ * arg.w_ * arg.c_;
for(index_t iH = 0; iH < arg.h_; iH++)
{
index_t offset_H = iH * arg.w_ * arg.c_;
for(index_t iW = 0; iW < arg.w_; iW++)
{
index_t offset_W = iW * arg.c_;
auto offset = offset_N + offset_H + offset_W + offset_C;
AccDataType x = type_convert<AccDataType>(arg.p_x_[offset]);
mean += x;
meansquare += x * x;
};
}
};
mean = mean / reduceSize;
meansquare = meansquare / reduceSize;
AccDataType variance = meansquare - mean * mean;
invVar = type_convert<AccDataType>(1.0f) /
std::sqrt(type_convert<AccDataType>(arg.epsilon_) + variance);
};
AccDataType dbias = type_convert<AccDataType>(0.0f); // Sum on NHW of dy
AccDataType dscale = type_convert<AccDataType>(0.0f); // Sum on NHW of dy * norm_x
// 1) calculate dy * (x - mean) * inv-variance
// 2) calculate sum(dy) on NHW dimensions
// 3) calculate sum(dy * norm_x) on NHW dimensions
for(index_t iN = 0; iN < arg.n_; iN++)
{
index_t offset_N = iN * arg.h_ * arg.w_ * arg.c_;
for(index_t iH = 0; iH < arg.h_; iH++)
{
index_t offset_H = iH * arg.w_ * arg.c_;
for(index_t iW = 0; iW < arg.w_; iW++)
{
index_t offset_W = iW * arg.c_;
auto offset = offset_N + offset_H + offset_W + offset_C;
AccDataType x = type_convert<AccDataType>(arg.p_x_[offset]);
AccDataType norm_x = (x - mean) * invVar;
AccDataType dy = type_convert<AccDataType>(arg.p_dy_[offset]);
arg.dy_elementwise_op_(dy, dy);
dbias += dy;
dscale += norm_x * dy;
};
}
};
arg.p_dscale_[offset_C] = type_convert<ScaleDataType>(dscale);
arg.p_dbias_[offset_C] = type_convert<BiasDataType>(dbias);
AccDataType scale = type_convert<AccDataType>(arg.p_scale_[offset_C]);
AccDataType multiplier =
type_convert<AccDataType>(1.0f) / reduceSize * invVar * scale;
// 1) calculate tmp = dscale * (x - mean) * inv-variance
// 2) calculate dx = 1/nhw * inv-variance * scale * (nhw * dy - dbias - tmp)
for(index_t iN = 0; iN < arg.n_; iN++)
{
index_t offset_N = iN * arg.h_ * arg.w_ * arg.c_;
for(index_t iH = 0; iH < arg.h_; iH++)
{
index_t offset_H = iH * arg.w_ * arg.c_;
for(index_t iW = 0; iW < arg.w_; iW++)
{
index_t offset_W = iW * arg.c_;
auto offset = offset_N + offset_H + offset_W + offset_C;
AccDataType x = type_convert<AccDataType>(arg.p_x_[offset]);
AccDataType norm_x = (x - mean) * invVar;
AccDataType dy = type_convert<AccDataType>(arg.p_dy_[offset]);
arg.dy_elementwise_op_(dy, dy);
AccDataType tmpVal = norm_x * dscale;
AccDataType dx = multiplier * (reduceSize * dy - dbias - tmpVal);
arg.p_dx_[offset] = type_convert<XDataType>(dx);
};
}
};
};
std::size_t num_thread = std::thread::hardware_concurrency();
std::size_t work_per_thread = (arg.c_ + num_thread - 1) / num_thread;
std::vector<joinable_thread> threads(num_thread);
for(std::size_t it = 0; it < num_thread; ++it)
{
std::size_t ic_begin = it * work_per_thread;
std::size_t ic_end = std::min(static_cast<int>((it + 1) * work_per_thread), arg.c_);
auto f = [=] {
for(std::size_t ic = ic_begin; ic < ic_end; ++ic)
{
thread_reduce_func(ic);
}
};
threads[it] = joinable_thread(f);
}
return (0.0f);
};
float Run(const device::BaseArgument* p_arg,
const StreamConfig& /*stream_config*/ = StreamConfig{}) override
{
return Run(*dynamic_cast<const Argument*>(p_arg));
};
};
bool IsSupportedArgument(const device::BaseArgument* p_arg) override
{
(void)p_arg;
return (true);
};
std::unique_ptr<device::BaseArgument>
MakeArgumentPointer(const std::array<index_t, 4> xyLengths,
const std::array<index_t, 4> xStrides,
const std::array<index_t, 4> dyStrides,
const std::array<index_t, 4> dxStrides,
const std::array<int, 3> reduceDims,
const std::array<ck::index_t, 1> bnScaleBiasMeanVarLengths,
const std::array<ck::index_t, 1> bnScaleStrides,
const std::array<ck::index_t, 1> bnBiasStrides,
const std::array<ck::index_t, 1> bnMeanVarStrides,
const void* p_x,
const void* p_dy,
const void* p_scale,
const void* p_savedMean,
const void* p_savedInvVar,
double epsilon,
const DyElementwiseOp dy_elementwise_op,
void* p_dx,
void* p_dscale,
void* p_dbias) override
{
return std::make_unique<Argument>(xyLengths,
xStrides,
dyStrides,
dxStrides,
reduceDims,
bnScaleBiasMeanVarLengths,
bnScaleStrides,
bnBiasStrides,
bnMeanVarStrides,
static_cast<const XDataType*>(p_x),
static_cast<const DyDataType*>(p_dy),
static_cast<const ScaleDataType*>(p_scale),
static_cast<const MeanVarDataType*>(p_savedMean),
static_cast<const MeanVarDataType*>(p_savedInvVar),
epsilon,
dy_elementwise_op,
static_cast<DxDataType*>(p_dx),
static_cast<ScaleDataType*>(p_dscale),
static_cast<BiasDataType*>(p_dbias));
};
std::unique_ptr<device::BaseInvoker> MakeInvokerPointer() override
{
return std::make_unique<Invoker>();
};
std::string GetTypeString() const override
{
auto str = std::stringstream();
// clang-format off
str << "Reference_BatchNorm_Backward_NHWC_C<" << std::endl;
// clang-format on
return str.str();
}
};
} // namespace host
} // namespace tensor_operation
} // namespace ck