#51 Better multithreading support

[Nick Mathewson]

It would be good to be able to tag callbacks as invocable from any thread, and have multiple worker threads running callbacks. If this goes far enough, we could even go to a situation with dispatch functions running independently in multiple threads. See Nick Black's libtorque work for some good ideas on that last point.

[Anonymous]

Is this problem can be solved used next concept?:
event_base_loop() {
lock(mutex);
while (...) {
dispatch(base);
c = get_callback(ev);
unlock(mutex);
do_callback( c );
lock(mutex);
}
unlock(mutex);
}

Mutex guarantee that dispatch be called by one thread, but functions callback can work in multiple threads.
I can wrote this patch.