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Re: corrected: tapset/script information template
On Sat, Apr 30, 2005 at 08:18:30PM -0400, Frank Ch. Eigler wrote:
> > I'm a bit confused by the semantics here. Is $dynamic_call_graph always
> > thread local? [...]
>
> Somewhat related, it may not be trivial to make oprofile-style data
> gathering local to a given thread. For one, the performance
> monitoring hardware doesn't know about context switches. Without
> that, other contexts would also pay for starting the probes, even if
> the probes return early. Will/Brad, can the counter management API we
> discussed two weeks ago deal with context switching awareness?
For thread-local counters, Mikael's perfctr has all the needed hooks in
place already; wouldn't that be the sensible thing to use?
> We intend to provide syntactic sugar for thread/process-specific
> values: "thread->VAR" would map onto "VAR[$tgid]", where "$tgid" would
> be the value of "current->tgid".
OK, this sounds good.
regards,
john