Create sub socpe when it is necessary

paddle/fluid/operators/detail/grpc_server.cc

@@ -60,7 +60,7 @@ class RequestSend final : public RequestBase {
                        framework::Scope* scope, ReceivedQueue* queue,
                        const platform::DeviceContext* dev_ctx)
       : RequestBase(service, cq, dev_ctx), queue_(queue), responder_(&ctx_) {
-    request_.reset(new VariableResponse(false, scope, dev_ctx_));
+    request_.reset(new VariableResponse(scope, dev_ctx_));
     int method_id = static_cast<int>(detail::GrpcMethod::kSendVariable);
     service_->RequestAsyncUnary(method_id, &ctx_, request_.get(), &responder_,
                                 cq_, cq_, this);
@@ -146,7 +146,7 @@ class RequestPrefetch final : public RequestBase {
         executor_(executor),
         program_(program),
         prefetch_ctx_(prefetch_ctx) {
-    request_.reset(new VariableResponse(false, scope, dev_ctx_));
+    request_.reset(new VariableResponse(scope, dev_ctx_));
     int method_id = static_cast<int>(detail::GrpcMethod::kPrefetchVariable);
     service_->RequestAsyncUnary(method_id, &ctx_, request_.get(), &responder_,
                                 cq_, cq_, this);

paddle/fluid/operators/detail/sendrecvop_utils.cc

@@ -186,7 +186,7 @@ void DeserializeFromByteBuffer(const ::grpc::ByteBuffer& msg,
                                const platform::DeviceContext& ctx,
                                const framework::Scope* scope,
                                framework::Variable** var) {
-  operators::detail::VariableResponse resp(false, scope, &ctx);
+  operators::detail::VariableResponse resp(scope, &ctx);
   PADDLE_ENFORCE(resp.Parse(msg) == 0, "parse bytebuffer to tensor error!");
   *var = resp.GetVar();
 }

paddle/fluid/operators/detail/serde_test.cc

@@ -51,7 +51,7 @@ void RunSerdeTestSelectedRows(platform::Place place) {
 
   ::grpc::ByteBuffer msg;
   operators::detail::SerializeToByteBuffer("myvar", &var, ctx, &msg);
-  EXPECT_GT(msg.Length(), 0);
+  EXPECT_GT(msg.Length(), static_cast<size_t>(0));
 
   // deserialize
   std::vector<::grpc::Slice> slices;
@@ -84,7 +84,7 @@ void RunSerdeTestSelectedRows(platform::Place place) {
   // operators::detail::DeserializeFromByteBuffer(msg, ctx, &var2);
   framework::Scope scope;
   scope.Var("myvar");
-  operators::detail::VariableResponse resp(false, &scope, &ctx);
+  operators::detail::VariableResponse resp(&scope, &ctx);
   EXPECT_EQ(resp.Parse(msg), 0);
 
   framework::Variable* var2 = resp.GetVar();
@@ -129,7 +129,7 @@ void RunTestLodTensor(platform::Place place, int from_type = 0) {
 
   ::grpc::ByteBuffer msg;
   operators::detail::SerializeToByteBuffer("myvar", &var, ctx, &msg);
-  EXPECT_GT(msg.Length(), 0);
+  EXPECT_GT(msg.Length(), static_cast<size_t>(0));
 
   // deserialize
   std::vector<::grpc::Slice> slices;
@@ -171,7 +171,7 @@ void RunTestLodTensor(platform::Place place, int from_type = 0) {
   // deserialize zero-copy
   framework::Scope scope;
   scope.Var("myvar");
-  operators::detail::VariableResponse resp(false, &scope, &ctx);
+  operators::detail::VariableResponse resp(&scope, &ctx);
   if (from_type == 0) {
     EXPECT_EQ(resp.Parse(msg), 0);
   } else {

paddle/fluid/operators/detail/variable_response.cc

@@ -114,7 +114,7 @@ bool VariableResponse::CopyLodTensorData(
     ::google::protobuf::io::CodedInputStream* input,
     const platform::DeviceContext& ctx, const framework::DDim& dims,
     int length) {
-  auto* tensor = InitVar()->GetMutable<framework::LoDTensor>();
+  auto* tensor = GetVar()->GetMutable<framework::LoDTensor>();
   tensor->Resize(dims);
 
   framework::LoD lod;
@@ -150,7 +150,7 @@ bool VariableResponse::CopySelectRowsTensorData(
     ::google::protobuf::io::CodedInputStream* input,
     const platform::DeviceContext& ctx, const framework::DDim& dims,
     int length) {
-  auto* slr = InitVar()->GetMutable<framework::SelectedRows>();
+  auto* slr = GetVar()->GetMutable<framework::SelectedRows>();
   slr->set_height(meta_.slr_height());
   auto* tensor = slr->mutable_value();
   tensor->Resize(dims);
@@ -172,7 +172,7 @@ bool VariableResponse::CopySelectRowsTensorData(
 bool VariableResponse::CopySelectRowsData(
     ::google::protobuf::io::CodedInputStream* input,
     const platform::DeviceContext& ctx, int length) {
-  auto* slr = InitVar()->GetMutable<framework::SelectedRows>();
+  auto* slr = GetVar()->GetMutable<framework::SelectedRows>();
   slr->mutable_rows()->resize(length /
                               framework::SizeOfType(typeid(int64_t)));  // int64
   int64_t* rows_data = slr->mutable_rows()->data();

paddle/fluid/operators/detail/variable_response.h

@@ -36,13 +36,18 @@ namespace detail {
 
 class VariableResponse {
  public:
-  VariableResponse(bool use_local_scope, const framework::Scope* scope,
-                   const platform::DeviceContext* dev_ctx)
-      : use_local_scope_(use_local_scope), scope_(scope), dev_ctx_(dev_ctx) {
-    local_scope_ = &scope->NewScope();
+  VariableResponse(const framework::Scope* scope,
+                   const platform::DeviceContext* dev_ctx,
+                   bool create_scope = false)
+      : scope_(scope), dev_ctx_(dev_ctx), create_scope_(create_scope) {
+    if (create_scope) {
+      local_scope_ = &scope->NewScope();
+    }
   }
 
-  virtual ~VariableResponse() { scope_->DeleteScope(local_scope_); }
+  virtual ~VariableResponse() {
+    if (create_scope_) scope_->DeleteScope(local_scope_);
+  }
 
   // return:
   // 0:ok.
@@ -63,17 +68,10 @@ class VariableResponse {
 
   // should call parse first.
   framework::Variable* GetVar() {
-    return local_scope_->FindVar(meta_.varname());
-  }
-
-  framework::Variable* InitVar() {
-    if (use_local_scope_) {
-      bool has_var = (scope_->FindVar(meta_.varname()) != nullptr);
-      PADDLE_ENFORCE(has_var);
+    if (create_scope_) {
       return local_scope_->Var(meta_.varname());
-    } else {
-      return scope_->FindVar(meta_.varname());
     }
+    return scope_->FindVar(meta_.varname());
   }
 
  private:
@@ -89,10 +87,10 @@ class VariableResponse {
                          const framework::DDim& dims, int length);
 
  private:
-  bool use_local_scope_ = false;
   const framework::Scope* scope_;
-  framework::Scope* local_scope_ = nullptr;
   const platform::DeviceContext* dev_ctx_;
+  bool create_scope_ = false;
+  framework::Scope* local_scope_ = nullptr;
   // only Skeleton
   sendrecv::VariableMessage meta_;
 };