TSAN job failing on CircleCI in libuv code

[lw]

https://app.circleci.com/pipelines/github/pytorch/tensorpipe/956/workflows/97acedc6-b2e9-449a-b010-65a4ead3b670/jobs/6759

That job failed because of a flaky TSAN data race, or actually three of them, all involving libuv and all looking similar: one thread was doing a uv_loop_init and the other one was doing a uv_tcp_init or _bind. However, from the thread numbers and the stack trace of their creation, it looks like these two operations were performed by two different UV contexts. It's weird that they would race.

See here for the traces:

https://gist.github.com/lw/fec763ca140ec9eb42a5991d694f3588