[torchelastic][multiprocessing] Print warning message only when child processes are stuck (#62823)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/62823
The diff makes sure that the warning message is printed only when the child processes are stuck after sending termination code.
Test Plan:
sandcastle
buck build mode/dev-nosan //caffe2:run
buck-out/gen/caffe2/run.par --nnodes 1 --nproc_per_node 1 main.py
P435691445
Differential Revision: D30046695
fbshipit-source-id: c59170b297f4a0e530906fa5069234303deee938
