This method allows us to avoid double-release()ing qutexes when we
want to release a qutex early. If we don't use releaseQutexEarly(),
then inside of callOriginalCb when LockSet::release is called, the
Qutex will be release()d a second time.
We now create the sh_ptr to the copy of a lockvoker object in its
own supplied register method. This enables us to retain type safety
when calling make_shared, by copying the most derived version of
the lockvoker object. Then we can pass in the LockerAndInvokerBase
to the rest of the call chain.
We now detect that a deadlock is likely when
CONFIG_DEBUG_QUTEX_DEADLOCK_TIMEOUT_MS has elapsed. This is the
preliminary work required to do a backtrace through the call
stack and figure out if a deadlock has really occured.
To do this, we'd have to go through the async call chain and
search for a previous caller which acquired the same qutex as
the one that first failed during this Lockvoker LockSet acquisition
attempt.
Implements: LockSet, SerializedAsynchronousContinuation,
LockerAndInvoker, LockerAndInvokerBase, Qutex.
Very big leap in functionality here. See qutexes.md for
an explanation of what we've done.