Destruct ConptyConnection on a background thread #7575
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This commit leverages C++/WinRT's final_release [extension point] to pull the final destruction of ConptyConnection off onto a background thread. We've been seeing some deadlocks during teardown where the output thread (holding the last owning reference to the connection) was trying to destruct the threadpool wait while the threadpool wait was simultaneously running its callback and waiting for the output thread to terminate. It turns out that trying to release a threadpool wait while it's running a callback that's blocked on you will absolutely result in a deadlock. Fixes #7392. [extension point]: https://devblogs.microsoft.com/oldnewthing/20191018-00
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This commit leverages C++/WinRT's final_release [extension point] to pull the final destruction of ConptyConnection off onto a background thread. We've been seeing some deadlocks during teardown where the output thread (holding the last owning reference to the connection) was trying to destruct the threadpool wait while the threadpool wait was simultaneously running its callback and waiting for the output thread to terminate. It turns out that trying to release a threadpool wait while it's running a callback that's blocked on you will absolutely result in a deadlock. Fixes #7392. [extension point]: https://devblogs.microsoft.com/oldnewthing/20191018-00/?p=103010 (cherry picked from commit 27f7ce7)
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This commit leverages C++/WinRT's final_release extension point to
pull the final destruction of ConptyConnection off onto a background
thread.
We've been seeing some deadlocks during teardown where the output thread
(holding the last owning reference to the connection) was trying to
destruct the threadpool wait while the threadpool wait was
simultaneously running its callback and waiting for the output thread to
terminate. It turns out that trying to release a threadpool wait while
it's running a callback that's blocked on you will absolutely result in
a deadlock.
Fixes #7392.