On Tue, 23.03.10 00:36, David Henningsson (launchpad.web at epost.diwic.se) wrote: > > What is missing is that the jack loop does not depend on the PA sink to > > be around resp. the PA IO loop doesn't call into jack when it is > > dead. If either of that is implemented (and then destruction order > > matches this) the problem is fixed. > > > > Also, what applies to m-jack-sink needs fixing in m-jack-source, too. > > Good points. I admit to not having checked properly whether > pa_sink_unlink and pa_sink_render_full can be called in parallell, I see > now that they shouldn't. Calling _unlink() and _render_full() at the same time is actually fine. _unlink() will send a msg to the IO thread to shut down the sink and will synchronously wait for it. _render_full() is called from the IO thread. Since the msg dispatching and the _render_full() are run from the same thread and hence are serialized there is no problem here. > Since appropriate stream moving is good, and stream moving (apparently) > needs to do a get-latency call to do its job properly, I would say that > this was a step in the right direction. Yes, you definitely found the problem. Only the fix is a bit harder than anticipated. > So, let us also send a message to the thread to stop rendering (i e stop > calling pa_sink_xxx), before the pa_sink_unlink call? If this sounds > like a good idea to you, I'll prepare a git patch. Yes, that sounds like a workable solution: 1) first send a synchronous msg from the main thread to the PA IO thread to tell it that PA_SINK_MESSAGE_GET_LATENCY shall no longer call into libjack. This can be implemented by a simple bool flag that is set on the PA IO thread side and which is checked on each _GET_LATENCY that is received. Because this msg is synchronous we can guarantee that after the msg was fully dispatched the PA IO thread won't hang inside a libjack call anymore. 2) We destroy the jack object. 3) We unlink and destroy the PA sink. AFAICS a logic like that would fix all issues. Lennart -- Lennart Poettering Red Hat, Inc. lennart [at] poettering [dot] net http://0pointer.net/lennart/ GnuPG 0x1A015CC4
