de819e579a
The backend may call update_latency() while at the same time the auto-connect-port calls set_worst_io_latencies(). The latter already holds the process-lock, so update_latency() first needs to acquire it, as well. If one already holds the _update_latency_lock, one must not ask for the process-lock. --- Previously Ardour's connection manager first took the process_lock and then waited to the _update_latency_lock. Meanwhile jack calls latency_callback(), takes the _update_latency_lock and waits for the process_lock. Classic deadlock.
Please see the Ardour web site at http://ardour.org/ for all documentation..
For information on building ardour:
http://ardour.org/development.html