pytorch

bf9d6658 - [DDP Comm Hook] Create a noop hook for performance debugging (#64344)

[DDP Comm Hook] Create a noop hook for performance debugging (#64344) Summary: Pull Request resolved: https://github.com/pytorch/pytorch/pull/64344 As title. Additionally, avoid using numpy array in test_ddp_hooks.py. ghstack-source-id: 137170449 Test Plan: buck test mode/dev-nosan caffe2/test/distributed/algorithms/ddp_comm_hooks:test_ddp_hooks -- test_ddp_comm_hook_noop_hook Reviewed By: rohan-varma Differential Revision: D30693220 fbshipit-source-id: e17f0d1c6198863cf20a53566f586a6bff602522