Re: Kaffeine problem with CFS

From: Ingo Molnar
Date: Wed Apr 18 2007 - 06:17:45 EST



* Christoph Pfister <christophpfister@xxxxxxxxx> wrote:

> It's nearly impossible for me to find out which mutex is deadlocking.

i've disassembled the xine_play function, and here are the function
calls in it:

<unresolved widget call?>
pthread_mutex_lock()
xine_log()
<unresolved widget call?>
function pointer call
right after it: pthread_mutex_lock()

this second pthread_mutex_lock() in question is the one that deadlocks.
It comes right after that function pointer call, maybe that identifies
it?

[some time passes]

i rebuilt the library from source and while the installed library is
different from it, looking at the disassembly i'm quite sure it's this
pthread_mutex_lock() in xine_play_internal():

pthread_mutex_lock( &stream->demux_lock );

src/xine-engine/xine.c:1201

the function pointer call was:

stream->xine->port_ticket->acquire(stream->xine->port_ticket, 1);

right before the pthread_mutex_lock() call.

> It would be great if you could reproduce the same problem with a
> xine-lib which has been compiled with debug support (so you'd get line
> numbers in the back trace - that makes life _a lot_ easier and maybe I
> could identify the problem that way) and the least optimization
> possible ... :-)

ok, i'll try that too (but it will take some more time), but given how
hard it was for me to trigger it, i wanted to get maximum info out of it
before having to kill the threads.

Ingo
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