[inductor] default cache_dir in torch._inductor.codecache should be lazily evaluated (#100824)

hsfzxjy · pytorchmergebot · commit b004c0b3c6a1 · 2023-05-10T03:36:39.000Z
`getpass.getuser` may raise exceptions in some circumstances, where users cannot override the default cache dir with env `TORCHINDUCTOR_CACHE_DIR`. Hence the assemble of default cache dir should be lazily evaluated. Pull Request resolved: #100824 Approved by: https://github.com/ezyang
diff --git a/torch/_inductor/codecache.py b/torch/_inductor/codecache.py
@@ -64,10 +64,9 @@ def _compile_end():
 
 @functools.lru_cache(None)
 def cache_dir():
-    cache_dir = os.environ.get(
-        "TORCHINDUCTOR_CACHE_DIR",
-        f"{tempfile.gettempdir()}/torchinductor_{getpass.getuser()}",
-    )
+    cache_dir = os.environ.get("TORCHINDUCTOR_CACHE_DIR")
+    if cache_dir is None:
+        cache_dir = f"{tempfile.gettempdir()}/torchinductor_{getpass.getuser()}"
     os.makedirs(cache_dir, exist_ok=True)
     return cache_dir
 
