This is the mail archive of the systemtap@sources.redhat.com mailing list for the systemtap project.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]
Other format: [Raw text]

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


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]