[OpenSER-Devel] need advice for avp lock

[Di-Shi Sun]

Hi Bogdan,

We use tm callback function ospTmcbFunc defined in module/osp/tm.c. It reads
a set of AVPs and creates some OSP internal data structures. Then starts
another thread to connect the OSP server. It worked fine except the race
condition. Do you recommend do it in onreply route block?

Thanks,

Di-Shi Sun.

----- Original Message ----- 
From: "Bogdan-Andrei Iancu" <bogdan at voice-system.ro>
To: "Di-Shi Sun" <di-shi at transnexus.com>
Cc: "Henning Westerholt" <henning.westerholt at 1und1.de>; <devel at openser.org>;
"Support of TransNexus" <support at transnexus.com>
Sent: Tuesday, October 23, 2007 10:51 PM
Subject: Re: [OpenSER-Devel] need advice for avp lock


> Hi Di-Shi,
>
> So you access this info from a callback and not from onreply
> route...What callback it is?
>
> Regards,
> Bogdan
>
> Di-Shi Sun wrote:
> > Hi Henning,
> >
> > Our case is like this:
> > 1. Our tm call back function was triggered by out 180 and 200. The
interval
> > between 180 and 200 was so short.
> > 2. The call back function accessed a set of AVPs and set a flag (in AVP
> > value) for every AVP to mark these AVPs were comsumed. This flag made
these
> > AVPs to be used only once. Since the call back function was called twice
at
> > almost the same time, the race condition happned that some AVPs were
used
> > twice.
> >
> > According the source code, we believe that USE_PTHREAD_MUTEX lock set is
> > thread safe and can be used for AVP. But the default lock set is
FAST_LOCK.
> > We do not know if it can be used for AVP.
> >
> > Regards,
> >
> > Di-Shi Sun.
> >
> > ----- Original Message ----- 
> > From: "Henning Westerholt" <henning.westerholt at 1und1.de>
> > To: "Di-Shi Sun" <di-shi at transnexus.com>
> > Cc: <devel at openser.org>; "Support of TransNexus"
<support at transnexus.com>
> > Sent: Tuesday, October 23, 2007 9:35 PM
> > Subject: Re: [OpenSER-Devel] need advice for avp lock
> >
> >
> >
> >> On Thursday 18 October 2007, Di-Shi Sun wrote:
> >>
> >>> Hi Henning,
> >>>
> >>> I believe we met the same problem. For us, only one flag in an AVP (5
> >>>
> > AVPs
> >
> >>> for a call) is set and the logic is simple. So, we did not meet a
crash
> >>> condition. It happened 17 times in a 1M call test at 50 cps.
> >>>
> >>> Klaus Darilion suggested we read the tm code for the AVP lock. I will
> >>>
> > study
> >
> >>> it.
> >>>
> >> I've studied this code too, but i found nothing helpful. What kind of
> >>
> > error
> >
> >> you've observed? In your first mail you spoke about a race condition,
is
> >>
> > the
> >
> >> wrong AVP value accessed?
> >>
> >> Cheers,
> >>
> >> Henning
> >>
> >>
> >>
> >
> >
> >
> > _______________________________________________
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> > Devel at openser.org
> > http://openser.org/cgi-bin/mailman/listinfo/devel
> >
> >
>
>
>