Robin Gareus 634d325e5d Prevent deadlock when disconnecting ... The backend holds `_port_callback_mutex` while disconnecting ports. In some cases disconnecting a port can drop the last reference resulting in a port-deletion from the connection handler. This in turn will eventually aquire the `_port_callback_mutex` and deadlock. This is now circumvented by using atomic operations instead of taking a lock to set the `_port_change_flag`. The flag is also used to trigger a latency update in some cases, atomic is preferable to taking a lock to set this flag. -- Full bt: https://paste.debian.net/1184056/ Short: #1 in pthread_mutex_lock () #2 in ARDOUR::PortEngineSharedImpl::port_connect_add_remove_callback() #3 in ARDOUR::BackendPort::~BackendPort() #4 in ARDOUR::DummyPort::~DummyPort() #6 in ARDOUR::DummyAudioPort::~DummyAudioPort() #7 in boost::checked_delete<ARDOUR::BackendPort>(ARDOUR::BackendPort*) #12 in boost::shared_ptr<ARDOUR::ProtoPort>::reset() #13 in ARDOUR::Port::drop() #14 in ARDOUR::Port::~Port() #15 in ARDOUR::AudioPort::~AudioPort() #17 in ARDOUR::AudioEngine::add_pending_port_deletion(ARDOUR::Port*) #20 in boost::detail::sp_counted_base::release() #37 in ARDOUR::PortManager::connect_callback() at libs/ardour/port_manager.cc:788 #38 in ARDOUR::DummyAudioBackend::main_process_thread() at libs/backends/dummy/dummy_audiobackend.cc:1018		2021-02-04 21:06:20 +01:00
..
dummy_audiobackend.cc	Prevent deadlock when disconnecting	2021-02-04 21:06:20 +01:00
dummy_audiobackend.h	NO-OP: Consolidate PortConnect code into shared parent class	2020-09-05 23:05:57 +02:00
dummy_midi_seq.h
wscript