[Fix] Update mmcv installation in dockerfile (#860)

* update dockerfile

* Update docker/Dockerfile

Co-authored-by: Jerry Jiarui XU <xvjiarui0826@gmail.com>

* add ARG

* change dash to bash

Co-authored-by: Jerry Jiarui XU <xvjiarui0826@gmail.com>

docker/Dockerfile

@@ -1,6 +1,7 @@
 ARG PYTORCH="1.6.0"
 ARG CUDA="10.1"
 ARG CUDNN="7"
+ARG MMCV="1.3.12"
 
 FROM pytorch/pytorch:${PYTORCH}-cuda${CUDA}-cudnn${CUDNN}-devel
 
@@ -12,11 +13,17 @@ RUN apt-get update && apt-get install -y git ninja-build libglib2.0-0 libsm6 lib
  && apt-get clean \
  && rm -rf /var/lib/apt/lists/*
 
-# Install mmsegmentation
 RUN conda clean --all
 
-RUN pip install mmcv-full==latest+torch1.6.0+cu101 -f https://download.openmmlab.com/mmcv/dist/index.html
+# Install MMCV
+ARG PYTORCH
+ARG CUDA
+ARG MMCV
+RUN ["/bin/bash", "-c", "pip install mmcv-full==${MMCV} -f https://download.openmmlab.com/mmcv/dist/cu${CUDA//./}/torch${PYTORCH}/index.html"]
+
+# Install MMSegmentation
 RUN git clone https://github.com/open-mmlab/mmsegmentation.git /mmsegmentation
 WORKDIR /mmsegmentation
+ENV FORCE_CUDA="1"
 RUN pip install -r requirements.txt
 RUN pip install --no-cache-dir -e .