[17/n][torch/elastic] Make torchelastic launcher compatible with the caffe2.distributed.launch (#55687)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/55687
The diff makes sure that users can transfer the following parameters:
* master_addr
* master_port
* node_rank
* use_env
The diff implement StaticTCPRendezvous that creates a store with listener on agent rank #0
The diff modifies caffe2/rendezvous: If the worker process launched with torchelastic agent, the worker processes will create a PrefixStore("worker/") from TCPStore without listener.
The diff adds macros functionality to torch/distributed/ealstic/utils that helps to resolve local_rank parameter.
Test Plan: buck test mode/dev-nosan //pytorch/elastic/torchelastic/distributed/test:launch_test
Reviewed By: cbalioglu, wilson100hong
Differential Revision: D27643206
fbshipit-source-id: 540fb26feac322cc3ec0a989fe53324755ccc4ea
