This adds a new helper that can be called from application code to
ensure that no mutexes are held on specific code paths. This is useful
for multiple scenarios, including ensuring no locks are held:
- at thread exit
- in peformance-critical code
- when a coroutine is suspended (can cause deadlocks)
See this discourse thread for more discussion:
https://discourse.llvm.org/t/add-threadsanitizer-check-to-prevent-coroutine-suspending-while-holding-a-lock-potential-deadlock/74051
This resubmits and fixes#69372 (was reverted because of build
breakage).
This also includes the followup change #71471 (to fix a land race).
The new lit test fails, see comment on the PR. This also reverts
the follow-up commit, see below.
> This adds a new helper that can be called from application code to
> ensure that no mutexes are held on specific code paths. This is useful
> for multiple scenarios, including ensuring no locks are held:
>
> - at thread exit
> - in peformance-critical code
> - when a coroutine is suspended (can cause deadlocks)
>
> See this discourse thread for more discussion:
>
> https://discourse.llvm.org/t/add-threadsanitizer-check-to-prevent-coroutine-suspending-while-holding-a-lock-potential-deadlock/74051
This reverts commit bd841111f340a73eb23c1be70ff1be4c8a6afb0c.
This reverts commit 16a395b74d35c564f6f36ba4a167950a323badd9.
