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2026-07-13 13:18:33 +08:00

222 lines
7.2 KiB
C++

// Copyright (c) Microsoft Corporation.
// SPDX-License-Identifier: Apache-2.0
// DeepSpeed Team
#include <torch/extension.h>
#include <cassert>
#include <cmath>
#include <functional>
#include <iostream>
#include <map>
#include <memory>
#include <type_traits>
#include <unordered_map>
#include "cpu_lion.h"
using namespace std::string_literals;
static std::unordered_map<int, std::shared_ptr<void>> s_optimizers;
// C++ interface
template <typename ds_params_precision_t, typename ds_state_precision_t>
void Lion_Optimizer::Step_1(ds_params_precision_t* _params,
ds_params_precision_t* grads,
ds_state_precision_t* _exp_avg,
size_t _param_size)
{
size_t rounded_size = 0;
#if defined(__AVX512__) or defined(__AVX256__)
Step_AVX<1>(&rounded_size, _params, grads, _exp_avg, _param_size);
#endif
if (_param_size > rounded_size) {
float betta1_minus1 = 1 - _betta1;
float betta2_minus1 = 1 - _betta2;
float alpha = _alpha;
float after_decay = 1 - alpha * _weight_decay;
for (size_t t = rounded_size; t < _param_size; t += TILE) {
size_t copy_size = TILE;
if ((t + TILE) > _param_size) copy_size = _param_size - t;
size_t offset = copy_size + t;
#pragma omp parallel for
for (size_t k = t; k < offset; k++) {
float grad = (float)grads[k];
float param = (float)_params[k];
float momentum = _exp_avg[k];
float tmp = momentum * _betta1;
tmp = grad * betta1_minus1 + tmp;
// Rely on portable C++ methods to manipulate the sign bit of a floating-point
// number.
tmp = -std::copysignf(alpha, tmp);
if (_weight_decay > 0) {
param = param * after_decay + tmp;
} else {
param = param + tmp;
}
momentum = momentum * _betta2;
momentum = grad * betta2_minus1 + momentum;
_params[k] = param;
_exp_avg[k] = momentum;
}
}
}
}
template <typename ds_params_precision_t, typename ds_state_precision_t>
void Lion_Optimizer::Step_4(ds_params_precision_t* _params,
ds_params_precision_t* grads,
ds_state_precision_t* _exp_avg,
size_t _param_size)
{
size_t rounded_size = 0;
#if defined(__AVX512__) or defined(__AVX256__)
Step_AVX<4>(&rounded_size, _params, grads, _exp_avg, _param_size);
#endif
if (_param_size > rounded_size)
Step_1((_params + rounded_size),
(grads + rounded_size),
(_exp_avg + rounded_size),
(_param_size - rounded_size));
}
int create_lion_optimizer(int optimizer_id,
float alpha,
float betta1,
float betta2,
float weight_decay,
bool should_log)
{
auto opt = std::make_shared<Lion_Optimizer>(alpha, betta1, betta2, weight_decay);
s_optimizers[optimizer_id] = opt;
if (should_log) {
std::string avx_type = "";
#if defined(__AVX512__)
avx_type = "AVX512";
#else
#if defined(__AVX256__)
avx_type = "AVX2";
#else
avx_type = "scalar";
#endif
#endif
printf("Lion Optimizer #%d is created with %s arithmetic capability.\n",
optimizer_id,
avx_type.c_str());
printf("Config: alpha=%f, betas=(%f, %f), weight_decay=%f\n",
alpha,
betta1,
betta2,
weight_decay);
}
return 0;
}
template <typename ds_params_precision_t, typename ds_state_precision_t>
void Lion_Optimizer::Step_8(ds_params_precision_t* _params,
ds_params_precision_t* grads,
ds_state_precision_t* _exp_avg,
size_t _param_size)
{
size_t rounded_size = 0;
#if defined(__AVX512__) or defined(__AVX256__)
Step_AVX<8>(&rounded_size, _params, grads, _exp_avg, _param_size);
#endif
if (_param_size > rounded_size)
Step_4((_params + rounded_size),
(grads + rounded_size),
(_exp_avg + rounded_size),
(_param_size - rounded_size));
}
template <typename ds_params_precision_t, typename ds_state_precision_t>
void step_invoker(std::shared_ptr<Lion_Optimizer> opt,
void* _params,
void* grads,
void* _exp_avg,
size_t _param_size)
{
opt->Step_8((ds_params_precision_t*)(_params),
(ds_params_precision_t*)(grads),
(ds_state_precision_t*)(_exp_avg),
_param_size);
}
std::map<std::tuple<c10::ScalarType, c10::ScalarType>,
std::function<void(std::shared_ptr<Lion_Optimizer>, void*, void*, void*, size_t)>>
invokers;
// Fill map with template functions for each type
template <class ds_params_precision_t, class ds_state_precision_t>
void create_invoker()
{
invokers[std::tuple(c10::CppTypeToScalarType<ds_params_precision_t>(),
c10::CppTypeToScalarType<ds_state_precision_t>())] =
step_invoker<ds_params_precision_t, ds_state_precision_t>;
}
struct InvokerInitializer {
InvokerInitializer()
{
create_invoker<c10::Half, float>();
create_invoker<c10::Half, c10::Half>();
create_invoker<c10::BFloat16, float>();
create_invoker<c10::BFloat16, c10::BFloat16>();
create_invoker<float, float>();
}
} _invoker_initializer;
void invoke(std::shared_ptr<Lion_Optimizer> opt,
torch::Tensor& params,
torch::Tensor& grads,
torch::Tensor& exp_avg,
size_t param_size)
{
c10::ScalarType params_type = at::typeMetaToScalarType(params.options().dtype());
c10::ScalarType state_type = at::typeMetaToScalarType(exp_avg.options().dtype());
auto it = invokers.find(std::tuple(params_type, state_type));
if (it == invokers.end()) {
throw std::runtime_error("Lion optimizer with param type "s + c10::toString(params_type) +
" and state type "s + c10::toString(state_type) +
" is not supported on current hardware"s);
}
it->second(opt, params.data_ptr(), grads.data_ptr(), exp_avg.data_ptr(), param_size);
}
int ds_lion_step(int optimizer_id,
size_t step,
float lr,
float beta1,
float beta2,
float weight_decay,
torch::Tensor& params,
torch::Tensor& grads,
torch::Tensor& exp_avg)
{
auto params_c = params.contiguous();
auto grads_c = grads.contiguous();
auto exp_avg_c = exp_avg.contiguous();
std::shared_ptr<Lion_Optimizer> opt =
std::static_pointer_cast<Lion_Optimizer>(s_optimizers[optimizer_id]);
opt->IncrementStep(step, beta1, beta2);
opt->update_state(lr, weight_decay);
invoke(opt, params_c, grads_c, exp_avg_c, params_c.numel());
return 0;
}
int destroy_lion_optimizer(int optimizer_id)
{
s_optimizers.erase(optimizer_id);
return 0;
}