avoid fork in torch/__init__.py for deploy/multipy (#90492)
Summary:
We should not fork in deploy when initializing torch.
Traceback (most recent call last):
File "<string>", line 38, in <module>
File "<string>", line 36, in __run
File "/usr/local/fbcode/platform010/lib/python3.8/runpy.py", line 194, in _run_module_as_main
return _run_code(code, main_globals, None,
File "/usr/local/fbcode/platform010/lib/python3.8/runpy.py", line 87, in _run_code
exec(code, run_globals)
File "/data/users/zyan/fbsource/buck-out/v2/gen/fbcode/104a4d5c3a690252/multipy/runtime/__test_py__/test_py#link-tree/multipy/runtime/test_py.py", line 61, in <module>
import torch # has to be done serially otherwise things will segfault
File "/data/users/zyan/fbsource/buck-out/v2/gen/fbcode/104a4d5c3a690252/multipy/runtime/__test_py__/test_py#link-tree/torch/__init__.py", line 158, in <module>
platform.system() != 'Windows':
File "/usr/local/fbcode/platform010/lib/python3.8/platform.py", line 891, in system
return uname().system
File "/usr/local/fbcode/platform010/lib/python3.8/platform.py", line 857, in uname
processor = _syscmd_uname('-p', '')
File "/usr/local/fbcode/platform010/lib/python3.8/platform.py", line 613, in _syscmd_uname
output = subprocess.check_output(('uname', option),
Test Plan: override a local script run trigger init and set `subprocess.check_output` to None
Reviewed By: yinghai, houseroad
Differential Revision: D41848592
Pull Request resolved: https://github.com/pytorch/pytorch/pull/90492
Approved by: https://github.com/PaliC
