remove tools/setup_helpers/cudnn.py (pytorch#25876)

Summary:
FindCUDNN.cmake and cuda.cmake have done the detection. This commit deletes `tools/setup_helpers/cudnn.py` as it is no longer needed.

Previously in pytorch#25482, one test failed because TensorRT detects cuDNN differently, and there may be situations we can find cuDNN but TensorRT cannot. This is fixed by passing our detection result down to TensorRT.
Pull Request resolved: pytorch#25876

Differential Revision: D17346270

Pulled By: ezyang

fbshipit-source-id: c1e7ad4a1cb20f964fe07a72906f2f002425d894

Author: xuhdev

cmake/Dependencies.cmake

@@ -1170,10 +1170,16 @@ if (CAFFE2_CMAKE_BUILDING_WITH_MAIN_REPO AND NOT INTERN_DISABLE_ONNX)
 endif()
 
 # --[ TensorRT integration with onnx-trt
+function (add_onnx_tensorrt_subdir)
+  # We pass the paths we found to onnx tensorrt.
+  set(CUDNN_INCLUDE_DIR "${CUDNN_INCLUDE_PATH}")
+  set(CUDNN_LIBRARY "${CUDNN_LIBRARY_PATH}")
+  add_subdirectory(${CMAKE_CURRENT_LIST_DIR}/../third_party/onnx-tensorrt EXCLUDE_FROM_ALL)
+endfunction()
 if (CAFFE2_CMAKE_BUILDING_WITH_MAIN_REPO)
   if (USE_TENSORRT)
     set(CMAKE_CUDA_COMPILER ${CUDA_NVCC_EXECUTABLE})
-    add_subdirectory(${CMAKE_CURRENT_LIST_DIR}/../third_party/onnx-tensorrt EXCLUDE_FROM_ALL)
+    add_onnx_tensorrt_subdir()
     include_directories("${CMAKE_CURRENT_LIST_DIR}/../third_party/onnx-tensorrt")
     caffe2_interface_library(nvonnxparser_static onnx_trt_library)
     list(APPEND Caffe2_DEPENDENCY_WHOLE_LINK_LIBS onnx_trt_library)

setup.py

@@ -185,7 +185,6 @@
                                      check_env_flag, build_type)
 from tools.setup_helpers.cmake import CMake
 from tools.setup_helpers.cuda import CUDA_HOME, CUDA_VERSION
-from tools.setup_helpers.cudnn import CUDNN_LIBRARY, CUDNN_INCLUDE_DIR
 
 try:
     FileNotFoundError
@@ -377,7 +376,8 @@ def run(self):
         else:
             report('-- NumPy not found')
         if cmake_cache_vars['USE_CUDNN']:
-            report('-- Detected cuDNN at ' + CUDNN_LIBRARY + ', ' + CUDNN_INCLUDE_DIR)
+            report('-- Detected cuDNN at ' +
+                   cmake_cache_vars['CUDNN_LIBRARY'] + ', ' + cmake_cache_vars['CUDNN_INCLUDE_DIR'])
         else:
             report('-- Not using cuDNN')
         if cmake_cache_vars['USE_CUDA']:

tools/build_pytorch_libs.py

@@ -6,7 +6,6 @@
 from .setup_helpers.env import IS_64BIT, IS_WINDOWS, check_negative_env_flag
 from .setup_helpers.cmake import USE_NINJA
 from .setup_helpers.cuda import USE_CUDA, CUDA_HOME
-from .setup_helpers.cudnn import CUDNN_INCLUDE_DIR, CUDNN_LIBRARY, USE_CUDNN
 
 
 def _overlay_windows_vcvars(env):
@@ -34,9 +33,6 @@ def _create_build_env():
     # you should NEVER add something to this list. It is bad practice to
     # have cmake read the environment
     my_env = os.environ.copy()
-    if USE_CUDNN:
-        my_env['CUDNN_LIBRARY'] = CUDNN_LIBRARY
-        my_env['CUDNN_INCLUDE_DIR'] = CUDNN_INCLUDE_DIR
     if USE_CUDA:
         my_env['CUDA_BIN_PATH'] = CUDA_HOME
 

tools/setup_helpers/cmake.py

@@ -215,6 +215,7 @@ def generate(self, version, cmake_python_library, build_python, build_test, my_e
             # adding a new build option to this block: Consider making these two names identical and adding this option
             # in the block below.
             '_GLIBCXX_USE_CXX11_ABI': 'GLIBCXX_USE_CXX11_ABI',
+            'CUDNN_LIB_DIR': 'CUDNN_LIBRARY',
             'USE_CUDA_STATIC_LINK': 'CAFFE2_STATIC_LINK_CUDA',
             'USE_GLOO_IBVERBS': 'USE_IBVERBS'   # Backward compatibility. Will be removed in the future.
         }
@@ -226,6 +227,8 @@ def generate(self, version, cmake_python_library, build_python, build_test, my_e
             ('BLAS',
              'BUILDING_WITH_TORCH_LIBS',
              'CUDA_NVCC_EXECUTABLE',
+             'CUDNN_LIBRARY',
+             'CUDNN_INCLUDE_DIR',
              'EXPERIMENTAL_SINGLE_THREAD_POOL',
              'INSTALL_TEST',
              'MKL_THREADING',