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Re: user instruction tracing patch?


Hi -

> > [...]
> >    probe program("/bin/vi").function("malloc")  { }
> > 
> > would be a request to probe all running (and forseeably, any future)
> > copies of vi.  To filter further, I imagine additional qualifiers such
> > as ".pid(NUM)", ".uid(NUM)".  These are all to identify the potential
> > probing target processes.
> 
> In the above examples, if NUM could be a variable name, then I think
> we're in business... especially if it could be a set of pids or uids
> [...]

Well, it depends how variable that data is.  Another way to think
about it is to think of the probe point type of specification as
"additive", and as conditionals as "subtractive".  If the data is
fixed at/near startup time, then we can "add" probes only to the
targeted processes and not bother any of the others.  If the data is
highly variable, it may be more appropriate to designate probes in
them all, and "subtract" out the uninteresting ones on the fly by
means of dynamic disabling conditions.

- FChE


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