[asterisk-dev] Question about #17888 and why it has been blocked

[Russell Bryant]

----- Original Message -----
> Am 11.09.2010 15:34, schrieb Russell Bryant:
> >
> > ----- Original Message -----
> >> i am very interested in the code which should be checked in with
> >> revision 286071 but david vossel has blocked it via svnmerge (thats
> >> wath the bot says)
> >>
> >> i have done some traceback of the subscribe and extension handling
> >> so
> >> i want to know what would be changed here. Is there a reviewboard
> >> for
> >> this (havent seen one).
> >
> > The patch was reviewed (by me) but outside of reviewboard on that
> > one. It was a pretty nasty deadlock, but due to some significant
> > changes to how device state and extension state are processed, the
> > bug only affects Asterisk 1.4.
> >
> thanks for your answer russel,
> 
> i just had several problems with the hint and state change handling
> and this would be the next place of my investigations so it was just
> interesting for me to see what has been changed.

The specific difference that mattered for this bug is that in 1.4, extension state changes are processed by calling a callback in chan_sip from main/pbx.c while holding some locks (the contexts lock and hints lock, I think it was).  In later versions, extension state changes are events in the Asterisk event API, so they are processed in chan_sip in a callback from the event distribution thread (main/event.c).

--
Russell Bryant
Digium, Inc.  |  Engineering Manager, Open Source Software
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