refine tensor copy from

paddle/framework/detail/tensor-inl.h

@@ -83,7 +83,7 @@ inline void Tensor::ShareDataWith(const Tensor& src) {
 
 template <typename T>
 inline void Tensor::CopyFrom(const Tensor& src,
-                             const platform::CPUPlace& dst_place) {
+                             const platform::Place& dst_place) {
   src.check_memory_size<T>();
   Resize(src.dims());
 
@@ -94,41 +94,27 @@ inline void Tensor::CopyFrom(const Tensor& src,
 
   auto size = product(src.dims_) * sizeof(T);
 
-  if (platform::is_cpu_place(src_place)) {
+  if (platform::is_cpu_place(src_place) && platform::is_cpu_place(dst_place)) {
     memory::Copy(boost::get<platform::CPUPlace>(dst_place), dst_ptr,
                  boost::get<platform::CPUPlace>(src_place), src_ptr, size);
   }
 #ifndef PADDLE_ONLY_CPU
-  else if (platform::is_gpu_place(src_place)) {
+  else if (platform::is_gpu_place(src_place) &&
+           platform::is_cpu_place(dst_place)) {
     memory::Copy(boost::get<platform::CPUPlace>(dst_place), dst_ptr,
                  boost::get<platform::GPUPlace>(src_place), src_ptr, size, 0);
-  }
-#endif
-}
-
-#ifndef PADDLE_ONLY_CPU
-template <typename T>
-inline void Tensor::CopyFrom(const Tensor& src,
-                             const platform::GPUPlace& dst_place) {
-  src.check_memory_size<T>();
-  Resize(src.dims());
-
-  auto src_place = src.holder_->place();
-  auto src_ptr = static_cast<const void*>(src.data<T>());
-
-  auto dst_ptr = static_cast<void*>(mutable_data<T>(dst_place));
-
-  auto size = product(src.dims_) * sizeof(T);
-
-  if (platform::is_cpu_place(src_place)) {
+  } else if (platform::is_cpu_place(src_place) &&
+             platform::is_gpu_place(dst_place)) {
     memory::Copy(boost::get<platform::GPUPlace>(dst_place), dst_ptr,
                  boost::get<platform::CPUPlace>(src_place), src_ptr, size, 0);
-  } else if (platform::is_gpu_place(src_place)) {
+  } else if (platform::is_gpu_place(src_place) &&
+             platform::is_gpu_place(dst_place)) {
     memory::Copy(boost::get<platform::GPUPlace>(dst_place), dst_ptr,
                  boost::get<platform::GPUPlace>(src_place), src_ptr, size, 0);
   }
-}
+
 #endif
+}
 
 template <typename T>
 inline Tensor Tensor::Slice(const int& begin_idx, const int& end_idx) const {

paddle/framework/tensor.h

@@ -94,14 +94,7 @@ class Tensor {
    * @note    CopyFrom supports CPU <-> GPU, GPU <-> GPU.
    */
   template <typename T>
-  inline void CopyFrom(const Tensor& src,
-                       const platform::CPUDeviceContext& ctx);
-
-#ifndef PADDLE_ONLY_CPU
-  template <typename T>
-  inline void CopyFrom(const Tensor& src,
-                       const platform::CUDADeviceContext& ctx);
-#endif
+  inline void CopyFrom(const Tensor& src, const platform::Place& dst_place);
 
   /**
    * @brief   Return the slice of the tensor.

paddle/memory/memcpy.cc

@@ -34,7 +34,7 @@ void Copy<platform::CPUPlace, platform::GPUPlace>(platform::CPUPlace dst_place,
                                                   void* dst,
                                                   platform::GPUPlace src_place,
                                                   const void* src, size_t num,
-                                                  cudaStream_t stream = 0) {
+                                                  cudaStream_t stream) {
   platform::SetDeviceId(src_place.device);
   platform::GpuMemcpyAsync(dst, src, num, cudaMemcpyDeviceToHost, stream);
 }
@@ -44,7 +44,7 @@ void Copy<platform::GPUPlace, platform::CPUPlace>(platform::GPUPlace dst_place,
                                                   void* dst,
                                                   platform::CPUPlace src_place,
                                                   const void* src, size_t num,
-                                                  cudaStream_t stream = 0) {
+                                                  cudaStream_t stream) {
   platform::SetDeviceId(dst_place.device);
   platform::GpuMemcpyAsync(dst, src, num, cudaMemcpyHostToDevice, stream);
 }
@@ -54,7 +54,7 @@ void Copy<platform::GPUPlace, platform::GPUPlace>(platform::GPUPlace dst_place,
                                                   void* dst,
                                                   platform::GPUPlace src_place,
                                                   const void* src, size_t num,
-                                                  cudaStream_t stream = 0) {
+                                                  cudaStream_t stream) {
   if (dst_place == src_place) {
     platform::SetDeviceId(src_place.device);
     platform::GpuMemcpyAsync(dst, src, num, cudaMemcpyDeviceToDevice, stream);

paddle/memory/memcpy.h

@@ -51,7 +51,7 @@ void Copy(DstPlace, void* dst, SrcPlace, const void* src, size_t num);
  */
 template <typename DstPlace, typename SrcPlace>
 void Copy(DstPlace, void* dst, SrcPlace, const void* src, size_t num,
-          cudaStream_t stream = 0);
+          cudaStream_t stream);
 
 #endif  // PADDLE_ONLY_CPU