How to test lock mode compatibility?

[Aleksey Shipilev]

On 08/31/2018 07:57 PM, Adam Retter wrote:
> However, the above involves not releasing the locks, which is fine for
> #tryLock because it is non-blocking, but will not work for #lock(). As
> such, I am struggling to devise a meaningful way to test with #lock()
> instead of #tryLock().

No go: you have to leave the lock in consistent state when leaving the @Actor, because otherwise the
whole might deadlock (as in, other @Actor can wait indefinitely for lock to be available).

> Can someone suggest a sensible way to do these compatibility checks?

This is what ReentrantLock mutex tests already do:

http://hg.openjdk.java.net/code-tools/jcstress/file/ff7cf32e6950/tests-custom/src/main/java/org/openjdk/jcstress/tests/locks/mutex/ReentrantLockMutexTests.java

They have the "witness" value that checks mutual exclusiveness.

-Aleksey