Messages in this thread | | | Subject | Re: malloc() tracing in perf? | From | Peter Zijlstra <> | Date | Thu, 06 Aug 2009 13:28:14 +0200 |
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On Thu, 2009-08-06 at 07:20 -0400, Frank Ch. Eigler wrote: > Hi - > > On Thu, Aug 06, 2009 at 10:16:50AM +0200, Peter Zijlstra wrote: > > [...] > > > But then it hit me, why can't I have kmemtrace + perf but for > > > user-space? Something like the "Malloc Trace" shown here: > > > [...] > > > I seem to have heard people are working on such a thing, but I can't > > seem to find a single LKML post with 'uprobe' in the subject in the > > past two years [...] > > That work is ongoing, and being discussed on utrace-devel@redhat.com, > since it is a prerequisite.
Still hiding the discussion and the design never helped anybody.
You might think it ready and then post it to LKML only to have it ripped apart -- have the discussion openly please.
> > Now doing probes on userspace is hard because you need to know more > > about the userspace bits than a kernel really ought to be interested > > in. [...] Anyway, like you say, it has uses (potentially very > > powerful ones), Sun/Apple do it with Dtrace, Linux wants it but I > > don't think we quite agreed on how to do it :-) > > While these deliberations are ongoing, you can use systemtap. Probing > random places in userspace is about as casual as probing the kernel:
Right, but that still doesn't tell us anything on how you're doing that, does it?
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