Re: [Ekiga-devel-list] Race condition for disconnect and OnConnected "event" with 2.0.9. Patch included.

[Craig Southeren <craigs postincrement com>]

Charlie Hedlin wrote:
> Yesterday I had Ekiga lock up.  Upon connecting with gdb I found that 
> two threads were hung trying to acquire locks.
> Thread 5 was processing the "OnConnected" even tfrom SipConnection, up 
> to OpalManager and down to OpalConnection::Released.  It was blocked on 
> LockReadWrite.
> Thread 1, the gui thread Called Manager::ClearCall (from the disconnect 
> button) and blocked in Call::Clear on LockReadOnly.
> I couldn't find any other threads blocking in unusual states.
>
> I have added a Mutex to GMManager that to block clearCall or OnConnected 
> events while the other is happening and have tested for around a hundred 
> calls without hanging, but I can't reliably reproduce this problem.  If 
> I make it through a few days without further lockups I will say it 
> likely worked.
>
> If this problem and fix can be confirmed it should probably be moved to 
> Opal.  I was trying to avoid having another custom package when I added 
> these calls to GMManager.
>
> I am attaching my patch.  Please disregard the SVN information, it is 
> from my local repository.

Robert has recently made a change to OPAL CVS head that reduces all
locks within a single call to one mutex. This has removed many possible
race conditions.

I would recommend looking at these new changes

   Craig

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 Craig Southeren          Post Increment – VoIP Consulting and Software
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