don't recompile cuda_ndarray.so if it was outdated, but someone else compiled it.

theano/sandbox/cuda/__init__.py

@@ -69,14 +69,6 @@ def set_cuda_disabled():
 
 #cuda_ndarray compile and import
 cuda_path = os.path.abspath(os.path.split(__file__)[0])
-cuda_files = (
-        'cuda_ndarray.cu',
-        'cuda_ndarray.cuh',
-        'conv_full_kernel.cu',
-        'conv_kernel.cu')
-stat_times = [os.stat(os.path.join(cuda_path, cuda_file))[stat.ST_MTIME]
-        for cuda_file in cuda_files]
-date = max(stat_times)
 
 cuda_ndarray_loc = os.path.join(config.compiledir, 'cuda_ndarray')
 cuda_ndarray_so = os.path.join(cuda_ndarray_loc,
@@ -85,6 +77,33 @@ libcuda_ndarray_so = os.path.join(cuda_ndarray_loc,
                                'libcuda_ndarray.' + get_lib_extension())
 
 
+def try_import():
+    """
+    load the cuda_ndarray module if present and up to date
+    return True if loaded correctly, otherwise return False
+    """
+    cuda_files = (
+        'cuda_ndarray.cu',
+        'cuda_ndarray.cuh',
+        'conv_full_kernel.cu',
+        'conv_kernel.cu')
+    stat_times = [os.stat(os.path.join(cuda_path, cuda_file))[stat.ST_MTIME]
+                  for cuda_file in cuda_files]
+    date = max(stat_times)
+    if os.path.exists(cuda_ndarray_so):
+        if date >= os.stat(cuda_ndarray_so)[stat.ST_MTIME]:
+            return False
+    try:
+        # If we load a previously-compiled version, config.compiledir should
+        # be in sys.path.
+        if config.compiledir not in sys.path:
+            sys.path.append(config.compiledir)
+        from cuda_ndarray.cuda_ndarray import *
+    except ImportError:
+        return False
+    return True
+
+
 # Add the theano cache directory's cuda_ndarray subdirectory to the
 # list of places that are hard-coded into compiled modules' runtime
 # library search list.  This works in conjunction with
@@ -95,41 +114,23 @@ nvcc_compiler.add_standard_rpath(cuda_ndarray_loc)
 
 compile_cuda_ndarray = True
 
-outdated = False
-if os.path.exists(cuda_ndarray_so):
-    outdated = date >= os.stat(cuda_ndarray_so)[stat.ST_MTIME]
-    compile_cuda_ndarray = outdated
 if not compile_cuda_ndarray:
-    try:
-        # If we load a previously-compiled version, config.compiledir should
-        # be in sys.path.
-        if config.compiledir not in sys.path:
-            sys.path.append(config.compiledir)
-        from cuda_ndarray.cuda_ndarray import *
-    except ImportError:
-        compile_cuda_ndarray = True
+    compile_cuda_ndarray = not try_import()
 
 if compile_cuda_ndarray:
     get_lock()
     try:
-        if not outdated:
-            # Maybe someone else compiled it while we got the lock.
-            try:
-                # If we load a previously-compiled version,
-                # config.compiledir should be in sys.path.
-                if config.compiledir not in sys.path:
-                    sys.path.append(config.compiledir)
-                from cuda_ndarray.cuda_ndarray import *
-                compile_cuda_ndarray = False
-            except ImportError:
-                compile_cuda_ndarray = True
-        if compile_cuda_ndarray:
+        # Retry to load again in case someone else compiled it
+        # while we waited for the lock
+        compile_cuda_ndarray = not try_import()
+        if not try_import():
             try:
                 if not nvcc_compiler.is_nvcc_available():
                     set_cuda_disabled()
 
                 if cuda_available:
-                    code = open(os.path.join(cuda_path, "cuda_ndarray.cu")).read()
+                    code = open(os.path.join(cuda_path,
+                                             "cuda_ndarray.cu")).read()
 
                     if not os.path.exists(cuda_ndarray_loc):
                         os.makedirs(cuda_ndarray_loc)