Re: kernel profiling artifact: Xspllower the leaf function

[Masao Uebayashi <uebayasi%gmail.com@localhost>]

On Fri, Jul 12, 2013 at 7:09 AM, David Young <dyoung%pobox.com@localhost> wrote:
> I am profiling a 6-ish kernel with kgmon/gprof.  I find that Xspllower
> is quite prominent in my profiles *and* that it looks like a
> "leaf"---that is, like it doesn't call anything.
>
> I suspect that the reason for Xspllower's prominence and "leafiness"
> is that it enters handlers for deferred interrupts in some "funny"
> way that does not create the type of stack frame that the profiler
> recognizes.  So gprof ascribes to Xspllower time that is in fact spent
> running handlers for the deferred interrupts.  Could that be?

> More to the point, is there an easy way to produce a more reliable profile?

I plan to improve tprof(8) support.  AFAIU it supports only NetBurst now.