xgboost/rabit/src/engine.cc
Andrew Ziem 3e7e426b36
Fix spelling in documents (#6948)
* Update roxygen2 doc.

Co-authored-by: fis <jm.yuan@outlook.com>
2021-05-11 20:44:36 +08:00

130 lines
3.6 KiB
C++

/*!
* Copyright (c) 2014 by Contributors
* \file engine.cc
* \brief this file governs which implementation of engine we are actually using
* provides an singleton of engine interface
*
* \author Tianqi Chen, Ignacio Cano, Tianyi Zhou
*/
#include <rabit/base.h>
#include <dmlc/thread_local.h>
#include <memory>
#include "rabit/internal/engine.h"
#include "allreduce_base.h"
namespace rabit {
namespace engine {
// singleton sync manager
#ifndef RABIT_USE_BASE
#ifndef RABIT_USE_MOCK
using Manager = AllreduceBase;
#else
typedef AllreduceMock Manager;
#endif // RABIT_USE_MOCK
#else
typedef AllreduceBase Manager;
#endif // RABIT_USE_BASE
/*! \brief entry to to easily hold returning information */
struct ThreadLocalEntry {
/*! \brief stores the current engine */
std::unique_ptr<Manager> engine;
/*! \brief whether init has been called */
bool initialized{false};
/*! \brief constructor */
ThreadLocalEntry() = default;
};
// define the threadlocal store.
using EngineThreadLocal = dmlc::ThreadLocalStore<ThreadLocalEntry>;
/*! \brief intiialize the synchronization module */
bool Init(int argc, char *argv[]) {
ThreadLocalEntry* e = EngineThreadLocal::Get();
if (e->engine.get() == nullptr) {
e->initialized = true;
e->engine.reset(new Manager());
return e->engine->Init(argc, argv);
} else {
return true;
}
}
/*! \brief finalize syncrhonization module */
bool Finalize() {
ThreadLocalEntry* e = EngineThreadLocal::Get();
if (e->engine.get() != nullptr) {
if (e->engine->Shutdown()) {
e->engine.reset(nullptr);
e->initialized = false;
return true;
} else {
return false;
}
} else {
return true;
}
}
/*! \brief singleton method to get engine */
IEngine *GetEngine() {
// un-initialized default manager.
static AllreduceBase default_manager;
ThreadLocalEntry* e = EngineThreadLocal::Get();
IEngine* ptr = e->engine.get();
if (ptr == nullptr) {
utils::Check(!e->initialized, "the rabit has not been initialized");
return &default_manager;
} else {
return ptr;
}
}
// perform in-place allgather, on sendrecvbuf
void Allgather(void *sendrecvbuf_, size_t total_size,
size_t slice_begin,
size_t slice_end,
size_t size_prev_slice) {
GetEngine()->Allgather(sendrecvbuf_, total_size, slice_begin,
slice_end, size_prev_slice);
}
// perform in-place allreduce, on sendrecvbuf
void Allreduce_(void *sendrecvbuf, // NOLINT
size_t type_nbytes,
size_t count,
IEngine::ReduceFunction red,
mpi::DataType,
mpi::OpType ,
IEngine::PreprocFunction prepare_fun,
void *prepare_arg) {
GetEngine()->Allreduce(sendrecvbuf, type_nbytes, count, red, prepare_fun,
prepare_arg);
}
// code for reduce handle
ReduceHandle::ReduceHandle() = default;
ReduceHandle::~ReduceHandle() = default;
int ReduceHandle::TypeSize(const MPI::Datatype &dtype) {
return static_cast<int>(dtype.type_size);
}
void ReduceHandle::Init(IEngine::ReduceFunction redfunc, size_t ) {
utils::Assert(redfunc_ == nullptr, "cannot initialize reduce handle twice");
redfunc_ = redfunc;
}
void ReduceHandle::Allreduce(void *sendrecvbuf,
size_t type_nbytes, size_t count,
IEngine::PreprocFunction prepare_fun,
void *prepare_arg) {
utils::Assert(redfunc_ != nullptr, "must initialize handle to call AllReduce");
GetEngine()->Allreduce(sendrecvbuf, type_nbytes, count,
redfunc_, prepare_fun, prepare_arg);
}
} // namespace engine
} // namespace rabit