Add the GPU version implementation of ImageExpandGrad function.

paddle/function/Im2ColOpGpu.cu

@@ -13,6 +13,7 @@ See the License for the specific language governing permissions and
 limitations under the License. */
 
 #include "Im2Col.h"
+#include "hl_device_functions.cuh"
 
 namespace paddle {
 
@@ -25,14 +26,13 @@ void im2colOCF(const T* imData, T* colData,
                int strideHeight, int strideWidth,
                int paddingHeight, int paddingWidth,
                int outputHeight, int outputWidth) {
-  int idx = threadIdx.x;
-  int idy = threadIdx.y;
   int swId = blockIdx.x;
   int shId = blockIdx.y;
-
   for (int channelId = threadIdx.z;
        channelId < inputChannels;
        channelId += blockDim.z) {
+    for (int idy = threadIdx.y; idy < filterHeight; idy += blockDim.y) {
+      for (int idx = threadIdx.x; idx < filterWidth; idx += blockDim.x) {
         int widthOffset = idx + swId * strideWidth - paddingWidth;
         int heightOffset = idy + shId * strideHeight - paddingHeight;
         int imOffset = widthOffset + heightOffset * inputWidth
@@ -43,7 +43,6 @@ void im2colOCF(const T* imData, T* colData,
           + (shId * outputWidth + swId)
           * (inputChannels * filterHeight * filterWidth);
 
-    if (idx < filterWidth && idy < filterHeight) {
         if (heightOffset >= inputHeight || heightOffset < 0 ||
             widthOffset >= inputWidth || widthOffset < 0) {
           colData[colOffset] = T(0);
@@ -52,6 +51,7 @@ void im2colOCF(const T* imData, T* colData,
         }
       }
     }
+  }
 }
 
 /*
@@ -105,6 +105,41 @@ public:
   }
 };
 
+template<class T>
+__global__
+void col2imOCF(T* imData, const T* colData,
+               int inputChannels,
+               int inputHeight, int inputWidth,
+               int filterHeight, int filterWidth,
+               int strideHeight, int strideWidth,
+               int paddingHeight, int paddingWidth,
+               int outputHeight, int outputWidth) {
+  int swId = blockIdx.x;
+  int shId = blockIdx.y;
+  for (int channelId = threadIdx.z;
+       channelId < inputChannels;
+       channelId += blockDim.z) {
+    for (int idy = threadIdx.y; idy < filterHeight; idy += blockDim.y) {
+      for (int idx = threadIdx.x; idx < filterWidth; idx += blockDim.x) {
+        int widthOffset = idx + swId * strideWidth - paddingWidth;
+        int heightOffset = idy + shId * strideHeight - paddingHeight;
+        int imOffset = widthOffset + heightOffset * inputWidth
+           + channelId * inputHeight * inputWidth;
+
+        int colOffset = idx + idy * filterWidth
+          + channelId * filterHeight * filterWidth
+          + (shId * outputWidth + swId)
+          * (inputChannels * filterHeight * filterWidth);
+
+        if (heightOffset >= 0 && heightOffset < inputHeight &&
+            widthOffset >= 0 && widthOffset < inputWidth) {
+          paddle::paddleAtomicAdd(imData + imOffset, colData[colOffset]);
+        }
+      }
+    }
+  }
+}
+
 /*
  * imShape = [inputChannels, inputHeight, inputWidth]
  * colShape =
@@ -121,10 +156,44 @@ public:
                   int strideWidth,
                   int paddingHeight,
                   int paddingWidth) {
+    int inputChannels = imShape[0];
+    int inputHeight = imShape[1];
+    int inputWidth = imShape[2];
+    int filterHeight = colShape[3];
+    int filterWidth = colShape[4];
+    int outputHeight = colShape[0];
+    int outputWidth = colShape[1];
+
+    int blockDimX = 0;
+    int blockDimY = 0;
+    if (filterHeight <= 4 && filterWidth <= 4) {
+      blockDimX = 4;
+      blockDimY = 4;
+    } else if (filterHeight <= 8 && filterWidth <= 8) {
+      blockDimX = 8;
+      blockDimY = 8;
+    } else if (filterHeight <= 16 && filterWidth <= 16) {
+      blockDimX = 16;
+      blockDimY = 16;
+    } else {
+      blockDimX = 32;
+      blockDimY = 32;
+    }
+
+    int blockDimZ = 1024 / blockDimX / blockDimY;
+    dim3 threads(blockDimX, blockDimY, std::min(blockDimZ, inputChannels));
+    dim3 grid(outputWidth, outputHeight);
+    col2imOCF<T><<< grid, threads, 0, STREAM_DEFAULT >>>
+        (imData, colData, inputChannels, inputHeight, inputWidth,
+         filterHeight, filterWidth, strideHeight, strideWidth,
+         paddingHeight, paddingWidth, outputHeight, outputWidth);
+    CHECK_SYNC("Col2ImFunctor GPU failed");
   }
 };
 
 template class Im2ColFunctor<kOCF, DEVICE_TYPE_GPU, float>;
 template class Im2ColFunctor<kOCF, DEVICE_TYPE_GPU, double>;
+template class Col2ImFunctor<kOCF, DEVICE_TYPE_GPU, float>;
+template class Col2ImFunctor<kOCF, DEVICE_TYPE_GPU, double>;
 
 }  // namespace paddle

paddle/function/ImageExpandOp.cpp

@@ -293,6 +293,7 @@ REGISTER_TYPED_FUNC(ImageExpand, CPU, ImageExpandForward);
 REGISTER_TYPED_FUNC(ImageExpandGrad, CPU, ImageExpandBackward);
 #ifndef PADDLE_ONLY_CPU
 REGISTER_TYPED_FUNC(ImageExpand, GPU, ImageExpandForward);
+REGISTER_TYPED_FUNC(ImageExpandGrad, GPU, ImageExpandBackward);
 #endif
 
 }  // namespace paddle

paddle/gserver/layers/BlockExpandLayer.cpp

@@ -46,14 +46,12 @@ bool BlockExpandLayer::init(const LayerMap& layerMap,
                      .set("strides", strides)
                      .set("paddings", paddings)
                      .set("blocks", blocks));
-  if (!useGpu_) {
   createFunction(backward_,
                  "ImageExpandGrad",
                  FuncConfig()
                      .set("strides", strides)
                      .set("paddings", paddings)
                      .set("blocks", blocks));
-  }
 
   return true;
 }
@@ -110,14 +108,16 @@ void BlockExpandLayer::forward(PassType passType) {
 }
 
 void BlockExpandLayer::backward(const UpdateCallback& callback) {
-  size_t blockNum = outputH_ * outputW_;
-  size_t blockSize = blockH_ * blockW_ * channels_;
   /* Calculate the input layers error */
-  MatrixPtr preGrad = inputLayers_[0]->getOutputGrad();
-  if (!preGrad) {
-    return;
+  if (getInputGrad(0)) {
+    BufferArgs inputs;
+    BufferArgs outputs;
+    inputs.addArg(*getOutputGrad(), outputShape_);
+    outputs.addArg(*getInputGrad(0), inputShape_, ADD_TO);
+    backward_[0]->calc(inputs, outputs);
   }
 
+#if 0
   if (useGpu_) {
     MatrixPtr grad = getOutputGrad();
     MatrixPtr gradTrans = Matrix::create(blockSize, blockNum, false, useGpu_);
@@ -155,13 +155,8 @@ void BlockExpandLayer::backward(const UpdateCallback& callback) {
                              1.0,
                              1.0);
     }
-  } else {
-    BufferArgs inputs;
-    BufferArgs outputs;
-    inputs.addArg(*getOutputGrad(), outputShape_);
-    outputs.addArg(*getInputGrad(0), inputShape_, ADD_TO);
-    backward_[0]->calc(inputs, outputs);
   }
+#endif
 }
 
 }  // namespace paddle