tree 29cac85974c6eead0bf3a4c591c31ca88e831807
parent cd4481c13b0fb360b3cf35251cd05083bf58154c
author Wyatt Hepler <hepler@google.com> 1674528374 +0000
committer CQ Bot Account <pigweed-scoped@luci-project-accounts.iam.gserviceaccount.com> 1674528374 +0000

pw_rpc: Add function for yielding the RPC lock in C++

Upcoming CLs will require threads to yield the RPC lock while waiting
for a different thread to finish executing an RPC callback.

- Add a config option for selecting how to yield (busy loop,
  pw::this_thread::sleep_for(), pw::this_thread::yield()).
- Add dependencies on pw_thread if backends are defined.
- Have the pw_rpc:disable_global_mutex config select the busy loop yield
  approach, since platforms with the mutex disabled either do not
  support threading or exclusively use RPC from one thread.
- Disable the RPC lock on a few platforms with no RTOS.

Change-Id: I94517d66e04b51b95a911adac560426ee3683388
Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/126751
Commit-Queue: Auto-Submit <auto-submit@pigweed.google.com.iam.gserviceaccount.com>
Reviewed-by: Alexei Frolov <frolv@google.com>
Pigweed-Auto-Submit: Wyatt Hepler <hepler@google.com>