probe_irq_exit is the callback that the tracepoint will call.

So we have, at the moment, for "optimized probes" (written by hand, not
serialized dynamically):

tracepoint -> probe_irq_exit -> ltt_specialized_trace()

These "optimized probes" skip the marker code entirely. They are only
tied to markers for the event type definitions.

Thanks,

Mathieu


* Jyotiswarup Raiturkar ([email protected]) wrote:
> >> The probes are connected to the tracepoints with: kernel:marker.c:
> set_marker()
> 
> Actually my question was where is the actual trace out call made? For
> example for the tracepoint defined by DEFINE_TRACE(irq_exit), the trace
> out call is trace_irq_exit(). Similarly there is a trace marker called
> DEFINE_MARKER_TP() for irq_exit :
> Kernel-trace.c : 
>       DEFINE_MARKER_TP(kernel, irq_exit, irq_exit, probe_irq_exit,
> "handled #1u%u");
> 
> But I don't see how this marker is actually hit during execution. What
> is the call similar to trace_irq_exit() for the Tracepoint?
> 
> Thanks
> Jyotiswarup Raiturkar
> 
> -----Original Message-----
> From: Mathieu Desnoyers [mailto:[email protected]] 
> Sent: Wednesday, May 19, 2010 8:00 PM
> To: Jyotiswarup Raiturkar
> Cc: [email protected]
> Subject: Re: [ltt-dev] LLTng probes
> 
> * Jyotiswarup Raiturkar ([email protected]) wrote:
> > Hello
> > 
> >  
> > 
> > I'm looking at LTTng working inside the kernel, and trying to
> understand
> > the instrumentation.
> > 
> >  
> > 
> > However, I am not able to see how the DEFINE_MARKER_TP() macros and
> > other probe_* functions in kernel-trace.c are actually used . As I
> > understand it, to make the actual trace, modules would have to call
> the
> > probe_* functions; yet I'm not able to locate these calls.
> 
> The probes are connected to the tracepoints with:
> 
> kernel:marker.c: set_marker()
> 
>                      ret = tracepoint_probe_register_noupdate(
>                                 elem->tp_name,
>                                 elem->tp_cb);
> 
> Which is called when a marker is enabled. The markers are listed in a
> table which is defined by the DEFINE_MARKER_TP() macros.
> 
> Thanks,
> 
> Mathieu
> 
> > 
> >  
> > 
> > Thanks
> > 
> > Jyoti
> > 
> > -- 
> > IMPORTANT NOTICE: The contents of this email and any attachments are
> confidential and may also be privileged. If you are not the intended
> recipient, please notify the sender immediately and do not disclose the
> contents to any other person, use it for any purpose, or store or copy
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> 
> > _______________________________________________
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> > [email protected]
> > http://lists.casi.polymtl.ca/cgi-bin/mailman/listinfo/ltt-dev
> 
> 
> -- 
> Mathieu Desnoyers
> Operating System Efficiency R&D Consultant
> EfficiOS Inc.
> http://www.efficios.com
> -- 
> IMPORTANT NOTICE: The contents of this email and any attachments are 
> confidential and may also be privileged. If you are not the intended 
> recipient, please notify the sender immediately and do not disclose the 
> contents to any other person, use it for any purpose, or store or copy the 
> information in any medium.  Thank you.
> 

-- 
Mathieu Desnoyers
Operating System Efficiency R&D Consultant
EfficiOS Inc.
http://www.efficios.com

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