[compile] Add fallback path to AOT compile when serialization fails. (#27350)

Signed-off-by: zhxchen17 <zhxchen17@fb.com>
Co-authored-by: Cyrus Leung <tlleungac@connect.ust.hk>

vllm/compilation/decorators.py

@@ -403,8 +403,17 @@ def _support_torch_compile(
                     output = self.aot_compiled_fn(self, *args, **kwargs)
                     assert aot_compilation_path is not None
                     assert cache_dir is not None
-                    os.makedirs(cache_dir, exist_ok=True)
-                    self.aot_compiled_fn.save_compiled_function(aot_compilation_path)
+                    try:
+                        os.makedirs(cache_dir, exist_ok=True)
+                        self.aot_compiled_fn.save_compiled_function(
+                            aot_compilation_path
+                        )
+                    except Exception as e:
+                        logger.warning(
+                            "Cannot save aot compilation to path %s, error: %s",
+                            aot_compilation_path,
+                            str(e),
+                        )
                 else:
                     output = self.compiled_callable(*args, **kwargs)
             return output