distributed_py.cc 22.5 KB
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/* Copyright (c) 2022 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. */

#include <fcntl.h>
#ifdef _POSIX_C_SOURCE
#undef _POSIX_C_SOURCE
#endif

#ifdef _XOPEN_SOURCE
#undef _XOPEN_SOURCE
#endif

#include "paddle/fluid/distributed/collective/ProcessGroup.h"
#include "paddle/fluid/distributed/collective/Types.h"
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#include "paddle/fluid/distributed/collective/reducer.h"
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#include "paddle/fluid/framework/lod_tensor.h"
#include "paddle/fluid/framework/tensor.h"
#include "paddle/fluid/imperative/layer.h"
#include "paddle/fluid/pybind/distributed_py.h"
#include "paddle/fluid/pybind/eager_utils.h"
#include "paddle/phi/api/all.h"

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#if defined(PADDLE_WITH_NCCL) || defined(PADDLE_WITH_RCCL)
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#include "paddle/fluid/distributed/collective/ProcessGroupNCCL.h"
#endif

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#if defined(PADDLE_WITH_ASCEND_CL)
#include "paddle/fluid/distributed/collective/ProcessGroupHCCL.h"
#endif

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#if defined(PADDLE_WITH_CUSTOM_DEVICE)
#include "paddle/fluid/distributed/collective/ProcessGroupCustom.h"
#endif

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#if defined(PADDLE_WITH_GLOO) && defined(PADDLE_WITH_PSCORE) && \
    (defined(PADDLE_WITH_NCCL) || defined(PADDLE_WITH_ASCEND_CL))
#include "paddle/fluid/distributed/collective/ProcessGroupHeter.h"
#endif

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#if defined(PADDLE_WITH_GLOO)
#include "paddle/fluid/distributed/collective/ProcessGroupGloo.h"
#include "paddle/fluid/distributed/store/tcp_store.h"
#endif

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namespace py = pybind11;

namespace paddle {
namespace pybind {

using Tensor = paddle::experimental::Tensor;

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std::shared_ptr<distributed::EagerReducer> CreateEagerReducer(
    py::handle py_tensors,
    const std::vector<std::vector<size_t>> &group_indices,
    const std::vector<bool> &is_sparse_gradient,
    std::shared_ptr<distributed::ProcessGroup> process_group,
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    const std::vector<size_t> &group_size_limits,
    bool find_unused_parameters) {
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  auto params = CastPyArg2VectorOfTensor(py_tensors.ptr(), 0);
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  return std::make_shared<distributed::EagerReducer>(params,
                                                     group_indices,
                                                     is_sparse_gradient,
                                                     process_group,
                                                     group_size_limits,
                                                     find_unused_parameters);
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}

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#if defined(PADDLE_WITH_GLOO)
using ProcessGroupGloo = paddle::distributed::ProcessGroupGloo;
using GlooStore = paddle::distributed::ProcessGroupGloo::GlooStore;
using GlooOptions = paddle::distributed::ProcessGroupGloo::GlooOptions;
#endif

static std::string GLOO_SOCKET_IFNAME_ENV = "GLOO_SOCKET_IFNAME";  // NOLINT

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void BindDistributed(py::module *m) {
  py::enum_<distributed::ReduceOp>(*m, "ReduceOp")
      .value("SUM", distributed::ReduceOp::SUM)
      .value("AVG", distributed::ReduceOp::AVG)
      .value("MAX", distributed::ReduceOp::MAX)
      .value("MIN", distributed::ReduceOp::MIN)
      .value("PRODUCT", distributed::ReduceOp::PRODUCT);

  py::class_<distributed::AllreduceOptions>(*m, "AllreduceOptions")
      .def(py::init<>())
      .def_readwrite("reduce_op", &distributed::AllreduceOptions::reduce_op);

  py::class_<distributed::BroadcastOptions>(*m, "BroadcastOptions")
      .def(py::init<>())
      .def_readwrite("source_rank", &distributed::BroadcastOptions::source_rank)
      .def_readwrite("source_root",
                     &distributed::BroadcastOptions::source_root);

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  py::class_<distributed::BarrierOptions>(*m, "BarrierOptions")
      .def(py::init<>())
      .def_readwrite("place_ids", &distributed::BarrierOptions::place_ids);

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  py::class_<distributed::ReduceOptions>(*m, "ReduceOptions")
      .def(py::init<>())
      .def_readwrite("reduce_op", &distributed::ReduceOptions::reduce_op)
      .def_readwrite("source_root", &distributed::ReduceOptions::root_rank);

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  auto ProcessGroup =
      py::class_<distributed::ProcessGroup,
                 std::shared_ptr<distributed::ProcessGroup>>(*m, "ProcessGroup")
          .def("rank", &distributed::ProcessGroup::GetRank)
          .def("size", &distributed::ProcessGroup::GetSize)
          .def("name", &distributed::ProcessGroup::GetBackendName)
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          .def(
              "allreduce",
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              [](distributed::ProcessGroup &self,
                 py::handle py_tensor,
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                 distributed::ReduceOp op) {
                auto tensor = CastPyArg2Tensor(py_tensor.ptr(), 0);
                distributed::AllreduceOptions opts;
                opts.reduce_op = op;
                auto dense =
                    std::dynamic_pointer_cast<phi::DenseTensor>(tensor.impl());
                std::vector<phi::DenseTensor> tensors = {*dense};
                return self.AllReduce(tensors, tensors, opts);
              },
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              py::arg("tensor"),
              py::arg("op") = distributed::ReduceOp::SUM,
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              py::call_guard<py::gil_scoped_release>())

          .def(
              "broadcast",
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              [](distributed::ProcessGroup &self,
                 py::handle py_tensor,
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                 int source_rank) {
                auto tensor = CastPyArg2Tensor(py_tensor.ptr(), 0);
                distributed::BroadcastOptions opts;
                opts.source_rank = source_rank;
                auto dense =
                    std::dynamic_pointer_cast<phi::DenseTensor>(tensor.impl());
                std::vector<phi::DenseTensor> tensors = {*dense};
                return self.Broadcast(tensors, tensors, opts);
              },
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              py::arg("tensor"),
              py::arg("source_rank"),
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              py::call_guard<py::gil_scoped_release>())

          .def(
              "barrier",
              [](distributed::ProcessGroup &self, std::vector<int> place_ids) {
                distributed::BarrierOptions opts;
                opts.place_ids = place_ids;
                return self.Barrier(opts);
              },
              py::arg("place_ids") = std::vector<int>{},
              py::call_guard<py::gil_scoped_release>())

          .def(
              "send",
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              [](distributed::ProcessGroup &self,
                 py::handle py_tensor,
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                 int dst) {
                auto tensor = CastPyArg2Tensor(py_tensor.ptr(), 0);
                auto dense =
                    std::dynamic_pointer_cast<phi::DenseTensor>(tensor.impl());
                std::vector<phi::DenseTensor> tensors = {*dense};
                return self.Send(tensors, dst);
              },
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              py::arg("tensor"),
              py::arg("dst"),
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              py::call_guard<py::gil_scoped_release>())

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          .def(
              "send_partial",
              [](distributed::ProcessGroup &self,
                 py::handle py_tensor,
                 int dst_rank,
                 int nranks,
                 int rank_id) {
                auto tensor = CastPyArg2Tensor(py_tensor.ptr(), 0);
                auto dense =
                    std::dynamic_pointer_cast<phi::DenseTensor>(tensor.impl());
                int numel = (*dense).numel();
                int send_numel = numel / nranks;
                int offset = send_numel * rank_id;
                return self.Send_Partial(*dense, dst_rank, offset, send_numel);
              },
              py::arg("tensor"),
              py::arg("dst"),
              py::arg("num"),
              py::arg("id"),
              py::call_guard<py::gil_scoped_release>())

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          .def(
              "recv",
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              [](distributed::ProcessGroup &self,
                 py::handle py_tensor,
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                 int src) {
                auto tensor = CastPyArg2Tensor(py_tensor.ptr(), 0);
                auto dense =
                    std::dynamic_pointer_cast<phi::DenseTensor>(tensor.impl());
                std::vector<phi::DenseTensor> tensors = {*dense};
                return self.Recv(tensors, src);
              },
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              py::arg("tensor"),
              py::arg("src"),
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              py::call_guard<py::gil_scoped_release>())

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          .def(
              "recv_partial",
              [](distributed::ProcessGroup &self,
                 py::handle py_tensor,
                 int src_rank,
                 int nranks,
                 int rank_id) {
                auto tensor = CastPyArg2Tensor(py_tensor.ptr(), 0);
                auto dense =
                    std::dynamic_pointer_cast<phi::DenseTensor>(tensor.impl());
                int numel = (*dense).numel();
                int recv_numel = numel / nranks;
                int offset = recv_numel * rank_id;
                return self.Recv_Partial(*dense, src_rank, offset, recv_numel);
              },
              py::arg("tensor"),
              py::arg("src"),
              py::arg("num"),
              py::arg("id"),
              py::call_guard<py::gil_scoped_release>())

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          .def(
              "all_gather",
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              [](distributed::ProcessGroup &self,
                 py::handle py_in_tensor,
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                 py::handle py_out_tensor) {
                auto in_tensor = CastPyArg2Tensor(py_in_tensor.ptr(), 0);
                auto out_tensor = CastPyArg2Tensor(py_out_tensor.ptr(), 0);
                auto in_dense = std::dynamic_pointer_cast<phi::DenseTensor>(
                    in_tensor.impl());
                auto out_dense = std::dynamic_pointer_cast<phi::DenseTensor>(
                    out_tensor.impl());
                std::vector<phi::DenseTensor> in_tensors = {*in_dense};
                std::vector<phi::DenseTensor> out_tensors = {*out_dense};
                return self.AllGather(in_tensors, out_tensors);
              },
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              py::arg("in"),
              py::arg("out"),
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              py::call_guard<py::gil_scoped_release>())

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          .def(
              "all_gather_partial",
              [](distributed::ProcessGroup &self,
                 py::handle py_in_tensor,
                 py::handle py_out_tensor,
                 int nranks,
                 int rank_id) {
                auto in_tensor = CastPyArg2Tensor(py_in_tensor.ptr(), 0);
                auto out_tensor = CastPyArg2Tensor(py_out_tensor.ptr(), 0);
                auto in_dense = std::dynamic_pointer_cast<phi::DenseTensor>(
                    in_tensor.impl());
                auto out_dense = std::dynamic_pointer_cast<phi::DenseTensor>(
                    out_tensor.impl());
                std::vector<phi::DenseTensor> in_tensors = {*in_dense};
                std::vector<phi::DenseTensor> out_tensors = {*out_dense};
                int numel = (*in_dense).numel();
                int send_numel = numel / nranks;
                int offset = send_numel * rank_id;
                return self.AllGather_Partial(
                    in_tensors, out_tensors, offset, send_numel);
              },
              py::arg("in"),
              py::arg("out"),
              py::arg("num"),
              py::arg("id"),
              py::call_guard<py::gil_scoped_release>())

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          .def(
              "alltoall",
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              [](distributed::ProcessGroup &self,
                 py::handle py_in_tensor,
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                 py::handle py_out_tensor) {
                auto in_tensor = CastPyArg2Tensor(py_in_tensor.ptr(), 0);
                auto out_tensor = CastPyArg2Tensor(py_out_tensor.ptr(), 0);
                auto in_dense = std::dynamic_pointer_cast<phi::DenseTensor>(
                    in_tensor.impl());
                auto out_dense = std::dynamic_pointer_cast<phi::DenseTensor>(
                    out_tensor.impl());
                std::vector<phi::DenseTensor> in_tensors = {*in_dense};
                std::vector<phi::DenseTensor> out_tensors = {*out_dense};
                return self.AllToAll(in_tensors, out_tensors);
              },
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              py::arg("in"),
              py::arg("out"),
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              py::call_guard<py::gil_scoped_release>())

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          .def(
              "alltoall_single",
              [](distributed::ProcessGroup &self,
                 py::handle py_in_tensor,
                 py::handle py_out_tensor,
                 std::vector<int64_t> in_sizes,
                 std::vector<int64_t> out_sizes) {
                auto in_tensor = CastPyArg2Tensor(py_in_tensor.ptr(), 0);
                auto out_tensor = CastPyArg2Tensor(py_out_tensor.ptr(), 0);
                auto in_dense = std::dynamic_pointer_cast<phi::DenseTensor>(
                    in_tensor.impl());
                auto out_dense = std::dynamic_pointer_cast<phi::DenseTensor>(
                    out_tensor.impl());
                std::vector<phi::DenseTensor> in_tensors = {*in_dense};
                std::vector<phi::DenseTensor> out_tensors = {*out_dense};
                return self.AllToAll_Single(
                    in_tensors, out_tensors, in_sizes, out_sizes);
              },
              py::arg("in"),
              py::arg("out"),
              py::arg("in_sizes"),
              py::arg("out_sizes"),
              py::call_guard<py::gil_scoped_release>())

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          .def(
              "reduce",
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              [](distributed::ProcessGroup &self,
                 py::handle py_in_tensor,
                 int dst,
                 distributed::ReduceOp op) {
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                auto in_tensor = CastPyArg2Tensor(py_in_tensor.ptr(), 0);
                distributed::ReduceOptions opts;
                opts.reduce_op = op;
                opts.root_rank = dst;
                auto dense = std::dynamic_pointer_cast<phi::DenseTensor>(
                    in_tensor.impl());
                std::vector<phi::DenseTensor> tensors = {*dense};
                return self.Reduce(tensors, tensors, opts);
              },
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              py::arg("tensor"),
              py::arg("dst"),
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              py::arg("op") = distributed::ReduceOp::SUM,
              py::call_guard<py::gil_scoped_release>())
          .def(
              "scatter",
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              [](distributed::ProcessGroup &self,
                 py::handle py_in_tensor,
                 py::handle py_out_tensor,
                 int src) {
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                auto in_tensor = CastPyArg2Tensor(py_in_tensor.ptr(), 0);
                auto out_tensor = CastPyArg2Tensor(py_out_tensor.ptr(), 0);
                distributed::ScatterOptions opts;
                opts.root_rank = src;
                auto in_dense = std::dynamic_pointer_cast<phi::DenseTensor>(
                    in_tensor.impl());
                auto out_dense = std::dynamic_pointer_cast<phi::DenseTensor>(
                    out_tensor.impl());
                std::vector<phi::DenseTensor> in_tensors = {*in_dense};
                std::vector<phi::DenseTensor> out_tensors = {*out_dense};
                return self.Scatter(in_tensors, out_tensors, opts);
              },
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              py::arg("in"),
              py::arg("out"),
              py::arg("src"),
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              py::call_guard<py::gil_scoped_release>())
          .def(
              "_reduce_scatter_base",
              [](distributed::ProcessGroup &self,
                 py::handle py_out_tensor,
                 py::handle py_in_tensor,
                 distributed::ReduceOp op) {
                auto in_tensor = CastPyArg2Tensor(py_in_tensor.ptr(), 0);
                auto out_tensor = CastPyArg2Tensor(py_out_tensor.ptr(), 0);
                distributed::ReduceScatterOptions opts;
                opts.reduce_op = op;
                auto dense_out = std::dynamic_pointer_cast<phi::DenseTensor>(
                    out_tensor.impl());
                auto dense_in = std::dynamic_pointer_cast<phi::DenseTensor>(
                    in_tensor.impl());
                return self._ReduceScatterBase(*dense_out, *dense_in, opts);
              },
              py::arg("out_tensor"),
              py::arg("in_tensor"),
              py::arg("op") = distributed::ReduceOp::SUM,
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              py::call_guard<py::gil_scoped_release>());
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#if defined(PADDLE_WITH_RCCL) || defined(PADDLE_WITH_NCCL)
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  auto processGroupNCCL =
      py::class_<distributed::ProcessGroupNCCL,
                 std::shared_ptr<distributed::ProcessGroupNCCL>>(
          *m, "ProcessGroupNCCL", ProcessGroup)
          .def(py::init<const std::shared_ptr<distributed::Store> &,
                        int,
                        int,
                        const platform::CUDAPlace &,
                        int>(),
               py::arg("store"),
               py::arg("rank"),
               py::arg("world_size"),
               py::arg("place"),
               py::arg("group_id") = 0,
               py::call_guard<py::gil_scoped_release>());

  processGroupNCCL.def_static(
      "group_start", []() { distributed::ProcessGroupNCCL::GroupStart(); });
  processGroupNCCL.def_static(
      "group_end", []() { distributed::ProcessGroupNCCL::GroupEnd(); });

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#endif
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#if defined(PADDLE_WITH_GLOO) && defined(PADDLE_WITH_PSCORE) && \
    (defined(PADDLE_WITH_NCCL) || defined(PADDLE_WITH_ASCEND_CL))
  py::class_<distributed::ProcessGroupHeter,
             std::shared_ptr<distributed::ProcessGroupHeter>>(
      *m, "ProcessGroupHeter", ProcessGroup)
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      .def(py::init<const std::shared_ptr<distributed::Store> &,
                    int,
                    int,
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#if defined(PADDLE_WITH_ASCEND_CL)
                    const platform::NPUPlace &,
#else
                    const platform::CUDAPlace &,
#endif
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                    int,
                    int,
                    int,
                    int,
                    int,
                    bool,
                    std::string,
                    int,
                    int>(),
           py::arg("store"),
           py::arg("rank"),
           py::arg("world_size"),
           py::arg("place"),
           py::arg("gid") = 0,
           py::arg("local_rank") = 0,
           py::arg("local_size") = 1,
           py::arg("gloo_rank") = 0,
           py::arg("gloo_size") = 1,
           py::arg("with_switch") = false,
           py::arg("switch_endpoint") = "",
           py::arg("src_rank") = "",
           py::arg("dst_rank") = "",
           py::call_guard<py::gil_scoped_release>());
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#endif
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#if defined(PADDLE_WITH_ASCEND_CL)
  py::class_<distributed::ProcessGroupHCCL,
             std::shared_ptr<distributed::ProcessGroupHCCL>>(
      *m, "ProcessGroupHCCL", ProcessGroup)
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      .def(py::init<const std::shared_ptr<distributed::Store> &,
                    int,
                    int,
                    const platform::NPUPlace &,
                    int>(),
           py::arg("store"),
           py::arg("rank"),
           py::arg("world_size"),
           py::arg("place"),
           py::arg("group_id") = 0,
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           py::call_guard<py::gil_scoped_release>());
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#endif

#if defined(PADDLE_WITH_CUSTOM_DEVICE)
  py::class_<distributed::ProcessGroupCustom,
             std::shared_ptr<distributed::ProcessGroupCustom>>(
      *m, "ProcessGroupCustom", ProcessGroup)
      .def(py::init<const std::shared_ptr<distributed::Store> &,
                    int,
                    int,
                    const platform::CustomPlace &,
                    int>(),
           py::arg("store"),
           py::arg("rank"),
           py::arg("world_size"),
           py::arg("place"),
           py::arg("group_id") = 0,
           py::call_guard<py::gil_scoped_release>());

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#endif

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  py::class_<distributed::ProcessGroup::Task,
             std::shared_ptr<distributed::ProcessGroup::Task>>(*m, "task")
      .def("is_completed", &distributed::ProcessGroup::Task::IsCompleted)
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      .def("wait",
           &distributed::ProcessGroup::Task::Wait,
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           py::arg("timeout") = kWaitTimeout,
           py::call_guard<py::gil_scoped_release>())
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      .def("synchronize",
           &distributed::ProcessGroup::Task::Synchronize,
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           py::call_guard<py::gil_scoped_release>());

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#if defined(PADDLE_WITH_GLOO)
  py::class_<ProcessGroupGloo, std::shared_ptr<ProcessGroupGloo>>(
      *m, "ProcessGroupGloo", ProcessGroup)
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      .def(py::init<const std::shared_ptr<paddle::distributed::Store> &,
                    int,
                    int,
                    const platform::CPUPlace &,
                    int,
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                    std::shared_ptr<GlooOptions> &>(),
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           py::call_guard<py::gil_scoped_release>())
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      .def(py::init([](const std::shared_ptr<paddle::distributed::Store> &store,
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                       int rank,
                       int world_size,
                       const platform::CPUPlace &place,
                       int gid) {
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             auto opts = GlooOptions::create();
             char *ifname = getenv(GLOO_SOCKET_IFNAME_ENV.c_str());
             if (ifname && strlen(ifname) > 1) {
               opts->device = ProcessGroupGloo::createDeviceForInterface(
                   std::string(ifname));
             } else {
               opts->device = ProcessGroupGloo::createDefaultDevice();
             }
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             return std::make_shared<ProcessGroupGloo>(
                 store, rank, world_size, place, gid, opts);
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           }),
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           py::arg("store"),
           py::arg("rank"),
           py::arg("world_size"),
           py::arg("place"),
           py::arg("group_id") = 0,
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           py::call_guard<py::gil_scoped_release>())
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      .def_static("create_default_device",
                  &ProcessGroupGloo::createDefaultDevice);
#endif

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  m->def(
      "eager_assign_group_by_size",
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      [](py::handle py_tensors,
         std::vector<bool> is_sparse_gradient,
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         std::vector<size_t> group_size_limits,
         std::vector<int64_t> tensor_indices) {
        auto tensors = CastPyArg2VectorOfTensor(py_tensors.ptr(), 0);
        return distributed::Eager_AssignGroupBySize(
            tensors, is_sparse_gradient, group_size_limits, tensor_indices);
      },
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      py::arg("tensors"),
      py::arg("is_sparse_gradient"),
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      py::arg("group_size_limits") = std::vector<size_t>{25 * 1024 * 1024},
      py::arg("tensor_indices") = std::vector<int64_t>{},
      py::call_guard<py::gil_scoped_release>());
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  py::class_<distributed::EagerReducer,
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             std::shared_ptr<distributed::EagerReducer>>(
      *m, "EagerReducer", R"DOC()DOC")
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      .def(py::init(&CreateEagerReducer))
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      .def(
          "prepare_for_backward",
          [](distributed::EagerReducer &self, py::handle py_tensors) {
            auto params = CastPyArg2VectorOfTensor(py_tensors.ptr(), 0);
            self.PrepareForBackward(params);
          },
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          py::arg("tensors"),
          py::call_guard<py::gil_scoped_release>());
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}

}  // end namespace pybind
}  // namespace paddle