noisy "Original exception being dropped" logs

[YAMAMOTO Takashi]

CallbackFailure related noisy log messages.

eg.

       ERROR [neutron.callbacks.manager] Callback neutron_vpnaas.db.vpn.vpn_db.vpn_callback--9223372036574151638 raised Subnet b3795775-0de9-4c75-bc9a-6f48bd1b2bb7 is used by VPNService a2913f9c-265b-4715-9294-789bb042b71f
       ERROR [root] Original exception being dropped: ['Traceback (most recent call last):\n', ' File "/Users/yamamoto/git/neutron-vpnaas/.tox/py27/src/neutron/neutron/db/l3_db.py", line 892, in _confirm_router_interface_not_in_use\n events.BEFORE_DELETE, self, **kwargs)\n', ' File "/Users/yamamoto/git/neutron-vpnaas/.tox/py27/src/neutron/neutron/callbacks/registry.py", line 44, in notify\n _get_callback_manager().notify(resource, event, trigger, **kwargs)\n', ' File "/Users/yamamoto/git/neutron-vpnaas/.tox/py27/src/neutron/neutron/db/api.py", line 179, in wrapped\n raise db_exc.RetryRequest(e)\n', ' File "/Users/yamamoto/git/neutron-vpnaas/.tox/py27/lib/python2.7/site-packages/oslo_utils/excutils.py", line 220, in __exit__\n self.force_reraise()\n', ' File "/Users/yamamoto/git/neutron-vpnaas/.tox/py27/lib/python2.7/site-packages/oslo_utils/excutils.py", line 196, in force_reraise\n six.reraise(self.type_, self.value, self.tb)\n', ' File "/Users/yamamoto/git/neutron-vpnaas/.tox/py27/src/neutron/neutron/db/api.py", line 174, in wrapped\n return f(*args, **kwargs)\n', ' File "/Users/yamamoto/git/neutron-vpnaas/.tox/py27/src/neutron/neutron/callbacks/manager.py", line 127, in notify\n raise exceptions.CallbackFailure(errors=errors)\n', 'CallbackFailure: Callback neutron_vpnaas.db.vpn.vpn_db.vpn_callback--9223372036574151638 failed with "Subnet b3795775-0de9-4c75-bc9a-6f48bd1b2bb7 is used by VPNService a2913f9c-265b-4715-9294-789bb042b71f"\n']

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/439981

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/439981
Committed: https://git.openstack.org/cgit/openstack/neutron/commit/?id=5bd08ce7f9283d8bf7789049e536a9957d54e41a
Submitter: Jenkins
Branch: master

commit 5bd08ce7f9283d8bf7789049e536a9957d54e41a
Author: YAMAMOTO Takashi <email address hidden>
Date: Thu Mar 2 12:52:25 2017 +0900

    Don't use save_and_reraise_exception when we never reraise

    Otherwise we get "Original exception being dropped" messages.

    Closes-Bug: #1669244
    Change-Id: Iecda4cce3f87c1a5a18cf365a3d6bdf5a8b4b514

[OpenStack Infra (hudson-openstack)]

This issue was fixed in the openstack/neutron 11.0.0.0b1 development milestone.