[omniORB] omniOrbPOA deadlock

[Renzo Tomaselli]

Hi all,
    there seems to be a deadlock in poa.cc which is due to the actual usage
of servant_activator_lock.
The sequence is:

1. A servant is deactivated and this invokes an etherealize method on its
servant activator. Before this occurrs,
the method omniOrbPOA::Etherealiser::doit() locks servant_activator_lock.
2. During etherealization some cleanup is performed by app. code; this
involves activating another servant through its servant activator. Although
colocated, the involved objref identity is remote, so that a receiving
thread wrapper must dispatch the request.
3. This is done in omniOrbPOA::dispatch_to_sa() method, which int turn tries
to lock servant_activator_lock and at this point we are blocked forever.

All of this seems due to the strange identity switch of objrefs when the
connected servant is deactivated: they switch from local to remote, so that
next invokation goes through the normal marshalling procedure of remote
objects and it calls back, although objref and servant are colocated.
I feel this influences performance of servants managed by a servant
activator, and even worse by servant locators. Beside the actual deadlock
off course.
Cheers,
                                             Renzo Tomaselli
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