follow comments and clean code

paddle/fluid/framework/details/broadcast_op_handle.cc

@@ -22,9 +22,9 @@ namespace details {
 
 void BroadcastOpHandle::RunImpl() {
   if (places_.size() == 1) return;
-  // the input and output may have dummy var.
-  VarHandle *in_var_handle;
 
+  // The input and output may have dummy vars.
+  VarHandle *in_var_handle;
   {
     auto in_var_handles = DynamicCast<VarHandle>(inputs_);
     PADDLE_ENFORCE_EQ(in_var_handles.size(), 1,
@@ -53,23 +53,39 @@ void BroadcastOpHandle::RunImpl() {
 
   Tensor &in_tensor = VariableVisitor::GetMutableTensor(in_var);
 
+  // NOTE(zcd): the Place of input can be get from in_tensor and in_var_handle ,
+  // maybe they are different, because the Place that getting from in_tensor is
+  // determined at runtime, the other is determined at building SSA graph stage.
+  // If they are different, DataTransform should be applied. Currently, it has
+  // not been done yet.
+  for (auto *out_var_handle : out_var_handles) {
+    if (*out_var_handle == *in_var_handle) {
+      continue;
+    }
+    auto &out_p = out_var_handle->place_;
+    auto *out_var = var_scopes.at(out_var_handle->scope_idx_)
+                        ->FindVar(out_var_handle->name_);
+    PADDLE_ENFORCE_NOT_NULL(out_var);
+    PADDLE_ENFORCE_EQ(
+        out_p.which(), in_tensor.place().which(),
+        "Currently, Places of input and output must be all on CPU "
+        "or all on GPU.");
+    VariableVisitor::ShareDimsAndLoD(*in_var, out_var);
+    VariableVisitor::GetMutableTensor(out_var).mutable_data(out_p,
+                                                            in_tensor.type());
+  }
+
   if (platform::is_cpu_place(in_tensor.place())) {
-    for (auto *out : out_var_handles) {
-      if (*out == *in_var_handle) {
+    for (auto *out_var_handle : out_var_handles) {
+      if (*out_var_handle == *in_var_handle) {
         continue;
       }
 
-      auto &out_p = out->place_;
-      auto *out_var = var_scopes.at(out->scope_idx_)->FindVar(out->name_);
-      PADDLE_ENFORCE_NOT_NULL(out_var);
-      PADDLE_ENFORCE_EQ(out_p.which(), in_tensor.place().which(),
-                        "Places must be all on CPU or all on CUDA.");
-
-      VariableVisitor::ShareDimsAndLoD(*in_var, out_var);
-      VariableVisitor::GetMutableTensor(out_var).mutable_data(out_p,
-                                                              in_tensor.type());
-
+      auto &out_p = out_var_handle->place_;
       auto dev_ctx = dev_ctxes_.at(out_p);
+      auto *out_var = var_scopes.at(out_var_handle->scope_idx_)
+                          ->FindVar(out_var_handle->name_);
+
       RunAndRecordEvent(out_p, [in_tensor, out_var, dev_ctx, out_p] {
         paddle::framework::TensorCopy(
             in_tensor, out_p, *dev_ctx,
@@ -78,35 +94,21 @@ void BroadcastOpHandle::RunImpl() {
     }
   } else {
 #ifdef PADDLE_WITH_CUDA
-    PADDLE_ENFORCE(platform::is_gpu_place(in_tensor.place()));
-    VarHandle *out_handle;
-    int root = boost::get<platform::CUDAPlace>(in_tensor.place()).device;
+    VarHandle *out_handle = nullptr;
+    int root_id = boost::get<platform::CUDAPlace>(in_tensor.place()).device;
     std::vector<std::function<void()>> broadcast_calls;
 
-    for (size_t j = 0; j < out_var_handles.size(); ++j) {
-      VarHandle *out_var_handle = out_var_handles[j];
+    for (auto out_var_handle : out_var_handles) {
       Variable *out_var = var_scopes.at(out_var_handle->scope_idx_)
                               ->FindVar(out_var_handle->name_);
 
-      if (*out_var_handle != *in_var_handle) {
-        PADDLE_ENFORCE_NOT_NULL(out_var);
-        PADDLE_ENFORCE_EQ(out_var_handle->place_.which(),
-                          in_tensor.place().which(),
-                          "Places must be all on CPU or all on CUDA.");
-        VariableVisitor::ShareDimsAndLoD(*in_var, out_var);
-        VariableVisitor::GetMutableTensor(out_var).mutable_data(
-            out_var_handle->place_, in_tensor.type());
-      }
+      int dst_id =
+          boost::get<platform::CUDAPlace>(out_var_handle->place_).device;
 
-      auto out_p = out_var_handle->place_;
-      int dev_id = boost::get<platform::CUDAPlace>(out_p).device;
-
-      auto &nccl_ctx = nccl_ctxs_->at(dev_id);
-      auto stream = nccl_ctx.stream();
-      auto comm = nccl_ctx.comm_;
+      auto &nccl_ctx = nccl_ctxs_->at(dst_id);
 
       void *send_recv_buffer = nullptr;
-      if (root == dev_id) {
+      if (root_id == dst_id) {
         send_recv_buffer = const_cast<void *>(in_tensor.data<void>());
         out_handle = out_var_handle;
       } else {
@@ -116,11 +118,13 @@ void BroadcastOpHandle::RunImpl() {
       }
 
       int type = platform::ToNCCLDataType(in_tensor.type());
-      broadcast_calls.emplace_back([=] {
-        PADDLE_ENFORCE(platform::dynload::ncclBcast(
-            send_recv_buffer, in_tensor.numel(),
-            static_cast<ncclDataType_t>(type), root, comm, stream));
-      });
+      size_t numel = static_cast<size_t>(in_tensor.numel());
+      broadcast_calls.emplace_back(
+          [send_recv_buffer, numel, type, root_id, &nccl_ctx] {
+            PADDLE_ENFORCE(platform::dynload::ncclBcast(
+                send_recv_buffer, numel, static_cast<ncclDataType_t>(type),
+                root_id, nccl_ctx.comm_, nccl_ctx.stream()));
+          });
     }
 
     this->RunAndRecordEvent([&] {
@@ -130,6 +134,7 @@ void BroadcastOpHandle::RunImpl() {
           call();
         }
       }
+      // TODO(zcd): Maybe the unequal operator is not appropriate here.
       if (*out_handle != *in_var_handle) {
         auto out_var = var_scopes.at(in_var_handle->scope_idx_)
                            ->FindVar(out_var_handles[0]->name_);
@@ -140,7 +145,7 @@ void BroadcastOpHandle::RunImpl() {
       }
     });
 #else
-    PADDLE_THROW("CUDA is not support.");
+    PADDLE_THROW("CUDA is not enabled.");
 #endif
   }
 }

paddle/fluid/framework/details/gather_op_handle.cc

@@ -36,7 +36,6 @@ void GatherOpHandle::RunImpl() {
   VarHandle *out_var_handle;
   {
     auto out_var_handles = DynamicCast<VarHandle>(outputs_);
-
     PADDLE_ENFORCE_EQ(out_var_handles.size(), 1,
                       "The number of output should be one.");
     out_var_handle = out_var_handles.front();
@@ -51,43 +50,39 @@ void GatherOpHandle::RunImpl() {
   auto pre_in_var =
       var_scopes.at(in_0_handle->scope_idx_)->FindVar(in_0_handle->name_);
   PADDLE_ENFORCE_NOT_NULL(pre_in_var);
+
   PADDLE_ENFORCE(pre_in_var->IsType<framework::SelectedRows>(),
                  "Currently, gather_op only can gather SelectedRows.");
 
   // Wait input done, this Wait is asynchronous operation
   WaitInputVarGenerated(in_var_handles);
 
+  auto &pre_in_value = pre_in_var->Get<framework::SelectedRows>();
   std::vector<int64_t> out_rows;
   std::vector<Tensor> in_tensors;
 
-  auto &pre_in_value = pre_in_var->Get<framework::SelectedRows>();
-  // gather the inputs
+  // Gather the inputs
   for (auto *in_handle : in_var_handles) {
     auto *in_var =
         var_scopes.at(in_handle->scope_idx_)->FindVar(in_handle->name_);
     PADDLE_ENFORCE_NOT_NULL(in_var);
+    VariableVisitor::EnforceShapeAndDTypeEQ(*in_var, *pre_in_var);
 
     auto &in_sr_value = in_var->Get<framework::SelectedRows>();
 
-    PADDLE_ENFORCE_EQ(in_sr_value.place().which(), pre_in_value.place().which(),
-                      "Places must be all on CPU or all on GPU.");
-    PADDLE_ENFORCE_EQ(in_sr_value.value().type(), pre_in_value.value().type(),
-                      "The type of input is not consistent.");
-    PADDLE_ENFORCE_EQ(in_sr_value.height(), pre_in_value.height(),
-                      "The height of inputs is not consistent.");
-    PADDLE_ENFORCE_EQ(in_sr_value.GetCompleteDims(),
-                      pre_in_value.GetCompleteDims(),
-                      "The dims of inputs is not consistent.");
-
     auto &in_sr_rows = in_sr_value.rows();
     out_rows.insert(out_rows.end(), in_sr_rows.begin(), in_sr_rows.end());
     in_tensors.emplace_back(in_sr_value.value());
   }
 
-  // write the output
+  // TODO(zcd): The Place of var_handle is determined at building SSA graph
+  // stage, while the Place of var is determined at runtime. If they are
+  // different, DataTransform should be applied. Currently, it has not been done
+  // yet.
   auto &out_place = out_var_handle->place_;
   PADDLE_ENFORCE_EQ(out_place.which(), pre_in_value.place().which(),
-                    "Places must be all on CPU or all on GPU.");
+                    "Currently, Places of input and output must be all on CPU "
+                    "or all on GPU.");
   auto out_var =
       var_scopes.at(out_var_handle->scope_idx_)->FindVar(out_var_handle->name_);
   PADDLE_ENFORCE_NOT_NULL(out_var);
@@ -97,19 +92,18 @@ void GatherOpHandle::RunImpl() {
   size_t rows = out_rows.size();
   DDim out_dim = pre_in_value.GetCompleteDims();
   out_dim[0] = static_cast<int64_t>(rows);
-  out_value->mutable_value()->Resize(out_dim);
-  out_value->mutable_value()->mutable_data(out_place,
-                                           pre_in_value.value().type());
+  out_value->mutable_value()->Resize(out_dim).mutable_data(
+      out_place, pre_in_value.value().type());
   Tensor *out_tensor = out_value->mutable_value();
 
   // copy
   auto dev_ctx = dev_ctxes_[out_place];
-  RunAndRecordEvent(out_place, [in_tensors, out_tensor, dev_ctx, out_place] {
+  RunAndRecordEvent(out_place, [in_tensors, out_tensor, &dev_ctx, out_place] {
     int s = 0, e = 0;
     for (size_t j = 0; j < in_tensors.size(); ++j) {
       e += in_tensors[j].dims()[0];
       auto sub_out = out_tensor->Slice(s, e);
-      paddle::framework::TensorCopy(in_tensors[j], out_place, *(dev_ctx),
+      paddle::framework::TensorCopy(in_tensors[j], out_place, *dev_ctx,
                                     &sub_out);
       s = e;
     }

paddle/fluid/framework/details/multi_devices_graph_builder.cc

@@ -116,13 +116,12 @@ std::unique_ptr<SSAGraph> MultiDevSSAGraphBuilder::Build(
       std::unordered_map<std::string, std::vector<std::unique_ptr<VarHandle>>>>(
       places_.size());
 
-  //  size_t cur_device_id = 0;
-  size_t update_sparse_gp_device_id = 0;
-  std::vector<std::unordered_set<std::string>> var_name_on_devices;
-  std::vector<std::unordered_set<std::string>> bcast_var_name_set;
+  size_t cur_update_sparse_gp_dev_id = 0;
+  std::vector<std::unordered_set<std::string>> sparse_var_name_on_devices;
+  std::vector<std::unordered_set<std::string>> bcast_sparse_var_name_set;
 
-  var_name_on_devices.resize(places_.size());
-  bcast_var_name_set.resize(places_.size());
+  sparse_var_name_on_devices.resize(places_.size());
+  bcast_sparse_var_name_set.resize(places_.size());
 
   // Find "send" op first for split is in front of send.
   OpDesc *send_op = GetSendOpDesc(program);
@@ -142,13 +141,13 @@ std::unique_ptr<SSAGraph> MultiDevSSAGraphBuilder::Build(
       }
       is_forwarding = false;
     } else {
-      int op_dev_id = GetOpDeviceID(var_name_on_devices, *op);
+      int op_dev_id = GetOpDeviceID(sparse_var_name_on_devices, *op);
       if (op_dev_id == -1) {  // var on all device
         CreateComputationalOps(&result, *op, places_.size());
       } else {
         CreateComputationalOp(&result, *op, op_dev_id);
         for (auto &var_name : op->OutputArgumentNames()) {
-          var_name_on_devices[op_dev_id].emplace(var_name);
+          sparse_var_name_on_devices[op_dev_id].emplace(var_name);
         }
       }
 
@@ -158,10 +157,13 @@ std::unique_ptr<SSAGraph> MultiDevSSAGraphBuilder::Build(
         for (auto &og : op->OutputArgumentNames()) {
           if (IsParameterGradientOnce(og, &og_has_been_broadcast)) {
             if (IsSparseGradient(og)) {
-              CreateReduceOp(&result, update_sparse_gp_device_id, og);
-              var_name_on_devices[update_sparse_gp_device_id].emplace(og);
-              bcast_var_name_set[update_sparse_gp_device_id].emplace(
+              CreateReduceOp(&result, cur_update_sparse_gp_dev_id, og);
+              sparse_var_name_on_devices[cur_update_sparse_gp_dev_id].emplace(
+                  og);
+              bcast_sparse_var_name_set[cur_update_sparse_gp_dev_id].emplace(
                   og.substr(0, og.size() - strlen(kGradVarSuffix)));
+              cur_update_sparse_gp_dev_id =
+                  (cur_update_sparse_gp_dev_id + 1) % places_.size();
             } else {
               InsertNCCLAllReduceOp(&result, og);
             }
@@ -172,8 +174,8 @@ std::unique_ptr<SSAGraph> MultiDevSSAGraphBuilder::Build(
   }
 
   // Insert BCast Ops
-  for (size_t dev_id = 0; dev_id < bcast_var_name_set.size(); ++dev_id) {
-    auto &to_bcast_set = bcast_var_name_set[dev_id];
+  for (size_t dev_id = 0; dev_id < bcast_sparse_var_name_set.size(); ++dev_id) {
+    auto &to_bcast_set = bcast_sparse_var_name_set[dev_id];
     for (auto &bcast_name : to_bcast_set) {
       CreateBroadcastOp(&result, bcast_name, dev_id);
     }
@@ -206,13 +208,14 @@ bool MultiDevSSAGraphBuilder::IsSparseGradient(const std::string &og) const {
 }
 
 int MultiDevSSAGraphBuilder::GetOpDeviceID(
-    const std::vector<std::unordered_set<std::string>> &var_name_on_devices,
+    const std::vector<std::unordered_set<std::string>>
+        &sparse_var_name_on_devices,
     const OpDesc &op) const {
   int var_dev_id = -1;
   for (auto &var_name : op.InputArgumentNames()) {
     if (var_dev_id != -1) break;
-    for (size_t i = 0; i < var_name_on_devices.size(); ++i) {
-      if (var_name_on_devices[i].count(var_name)) {
+    for (size_t i = 0; i < sparse_var_name_on_devices.size(); ++i) {
+      if (sparse_var_name_on_devices[i].count(var_name)) {
         var_dev_id = static_cast<int>(i);
         break;
       }

paddle/fluid/framework/details/reduce_op_handle.cc

@@ -52,27 +52,30 @@ void ReduceOpHandle::RunImpl() {
 
   // Wait input done, this Wait is asynchronous operation
   WaitInputVarGenerated(in_var_handles);
-  auto pre_place = in_0_handle->place_;
+
   std::vector<platform::Place> in_places;  // used to get dev_ctx
-  auto pre_in_tensor = VariableVisitor::GetMutableTensor(pre_in_var);
   for (auto *in_handle : in_var_handles) {
     in_places.emplace_back(in_handle->place_);
-
     auto in_var =
         var_scopes.at(in_handle->scope_idx_)->FindVar(in_handle->name_);
     PADDLE_ENFORCE_NOT_NULL(in_var);
-
-    auto in_tensor = VariableVisitor::GetMutableTensor(in_var);
-    PADDLE_ENFORCE_EQ(pre_in_tensor.place().which(), in_tensor.place().which(),
-                      "Places must be all on CPU or all on GPU.");
-    PADDLE_ENFORCE_EQ(in_tensor.type(), pre_in_tensor.type(),
-                      "The type of input is not consistent.");
+    VariableVisitor::EnforceShapeAndDTypeEQ(*pre_in_var, *in_var);
   }
 
   auto out_var =
       var_scopes.at(out_var_handle->scope_idx_)->FindVar(out_var_handle->name_);
   PADDLE_ENFORCE_NOT_NULL(out_var);
 
+  // TODO(zcd): The Place of var_handle is determined at building SSA graph
+  // stage, while the Place of var is determined at runtime. If they are
+  // different, DataTransform should be applied. Currently, it has not been done
+  // yet.
+  PADDLE_ENFORCE_EQ(
+      VariableVisitor::GetMutableTensor(pre_in_var).place().which(),
+      out_var_handle->place_.which(),
+      "Currently, Places of input and output must be all on CPU or all on "
+      "GPU.");
+
   if (pre_in_var->IsType<framework::SelectedRows>()) {
     std::vector<const SelectedRows *> in_selected_rows =
         GetInputValues<SelectedRows>(in_var_handles, var_scopes);
@@ -96,7 +99,7 @@ void ReduceOpHandle::RunImpl() {
           out_var_handle->place_, pre_in.type());
 
       auto out_p = out_var_handle->place_;
-      int root = boost::get<platform::CUDAPlace>(out_p).device;
+      int root_id = boost::get<platform::CUDAPlace>(out_p).device;
       std::vector<std::function<void()>> all_reduce_calls;
       for (size_t i = 0; i < var_scopes.size(); ++i) {
         auto &p = in_places[i];
@@ -104,23 +107,23 @@ void ReduceOpHandle::RunImpl() {
 
         int dev_id = boost::get<platform::CUDAPlace>(p).device;
         auto &nccl_ctx = nccl_ctxs_->at(dev_id);
-        auto stream = nccl_ctx.stream();
-        auto comm = nccl_ctx.comm_;
 
         void *buffer = const_cast<void *>(lod_tensor.data<void>());
         void *recvbuffer = nullptr;
-        if (root == dev_id) {
+        if (root_id == dev_id) {
           recvbuffer =
               out_var->GetMutable<framework::LoDTensor>()->mutable_data(
                   out_var_handle->place_);
         }
 
         int type = platform::ToNCCLDataType(lod_tensor.type());
-        all_reduce_calls.emplace_back([=] {
-          PADDLE_ENFORCE(platform::dynload::ncclReduce(
-              buffer, recvbuffer, static_cast<size_t>(lod_tensor.numel()),
-              static_cast<ncclDataType_t>(type), ncclSum, root, comm, stream));
-        });
+        size_t numel = static_cast<size_t>(lod_tensor.numel());
+        all_reduce_calls.emplace_back(
+            [buffer, recvbuffer, type, numel, root_id, &nccl_ctx] {
+              PADDLE_ENFORCE(platform::dynload::ncclReduce(
+                  buffer, recvbuffer, numel, static_cast<ncclDataType_t>(type),
+                  ncclSum, root_id, nccl_ctx.comm_, nccl_ctx.stream()));
+            });
       }
 
       this->RunAndRecordEvent([&] {
@@ -130,7 +133,7 @@ void ReduceOpHandle::RunImpl() {
         }
       });
 #else
-      PADDLE_THROW("CUDA is not support.");
+      PADDLE_THROW("CUDA is not enabled.");
 #endif
     } else {
       PADDLE_THROW("Place should be CPUPlace or CUDAPlace.");

paddle/fluid/framework/details/ssa_graph_builder.cc

@@ -47,17 +47,6 @@ void SSAGraphBuilder::PolishGraphToSupportDataHazards(SSAGraph *graph) {
   }
 }
 
-VarHandle *SSAGraphBuilder::GetLatestVarHandle(SSAGraph *graph,
-                                               const std::string &each_var_name,
-                                               size_t place_offset) {
-  auto &var_holders = graph->vars_[place_offset];
-  auto &var_holder = var_holders[each_var_name];
-  if (var_holder.empty()) {
-    return nullptr;
-  }
-  return var_holder.rbegin()->get();
-}
-
 VarHandle *SSAGraphBuilder::CreateOrGetLatestVarHandle(
     SSAGraph *graph, const std::string &each_var_name,
     const platform::Place &place, size_t place_offset) {

paddle/fluid/framework/details/var_handle.h

@@ -62,6 +62,16 @@ struct VarHandle : public VarHandleBase {
   std::string name_;
   platform::Place place_;
 
+  // NOTE(zcd): Strictly speaking, if the two var_handle is equal, the four
+  // member
+  // variables(version_, scope_id_, name_, place_) must be equal. But sometimes
+  // judging whether the two var_handle is equal is actually to determine
+  // whether
+  // the two Variables that represented by var_handle is the same. And the same
+  // Variable may have many different var_handles, the version_ of these
+  // var_handles
+  // is different. So I don't take care of version_ temporarily when overloading
+  // equal.
   bool operator==(const VarHandle& o) const {
     return o.generated_op_ == generated_op_ && o.name_ == name_ &&
            o.scope_idx_ == scope_idx_;

paddle/fluid/framework/details/variable_visitor.cc

@@ -88,6 +88,52 @@ void VariableVisitor::ShareDimsAndLoD(const Variable& src, Variable* trg) {
   VisitVariable(src, &visitor);
 }
 
+struct EnforceEqualShapeAndDTypeVisitor {
+  const Variable* trg_;
+
+  void operator()(const LoDTensor& src) {
+    auto& tensor = trg_->Get<LoDTensor>();
+    PADDLE_ENFORCE_EQ(
+        src.place().which(), tensor.place().which(),
+        "The Places of the two Variable must be all on CPU or all on GPU.");
+    PADDLE_ENFORCE_EQ(src.type(), tensor.type(),
+                      "The dtype of the two Variable is not equal.");
+    PADDLE_ENFORCE_EQ(src.dims(), tensor.dims(),
+                      "The dims of the two Variable is not equal.");
+    PADDLE_ENFORCE_EQ(src.lod(), tensor.lod(),
+                      "The lod of the two Variable is not equal.");
+    PADDLE_ENFORCE_EQ(src.layout(), tensor.layout(),
+                      "The layout of the two Variable's tensor is not equal.");
+  }
+
+  void operator()(const SelectedRows& src) {
+    auto& selected_rows = trg_->Get<SelectedRows>();
+    PADDLE_ENFORCE_EQ(
+        src.place().which(), selected_rows.place().which(),
+        "The Places of the two Variable must be all on CPU or all on GPU.");
+    PADDLE_ENFORCE_EQ(src.value().type(), selected_rows.value().type(),
+                      "The dtype of the two Variable is not equal.");
+    PADDLE_ENFORCE_EQ(src.value().layout(), selected_rows.value().layout(),
+                      "The layout of the two Variable's tensor is not equal.");
+    PADDLE_ENFORCE_EQ(src.height(), selected_rows.height(),
+                      "The height of the two Variable is not equal.");
+    PADDLE_ENFORCE_EQ(src.GetCompleteDims(), selected_rows.GetCompleteDims(),
+                      "The dims of the two Variable is not equal.");
+  }
+
+  template <typename T>
+  void operator()(const T&) {
+    PADDLE_ENFORCE("EnforceShapeAndDTypeEQ is not supported by type %s",
+                   typeid(T).name());
+  }
+};
+
+void VariableVisitor::EnforceShapeAndDTypeEQ(const Variable& var1,
+                                             const Variable& var2) {
+  EnforceEqualShapeAndDTypeVisitor visitor{&var1};
+  VisitVariable(var2, &visitor);
+}
+
 }  // namespace details
 }  // namespace framework
 }  // namespace paddle

paddle/fluid/framework/details/variable_visitor.h

@@ -26,6 +26,9 @@ class VariableVisitor {
   static Tensor &GetMutableTensor(Variable *var);
 
   static void ShareDimsAndLoD(const Variable &src, Variable *trg);
+
+  static void EnforceShapeAndDTypeEQ(const Variable &var1,
+                                     const Variable &var2);
 };
 
 }  // namespace details