Re: [PATCH] Kprobes: Add kprobes smoke tests that run on boot

[Andi Kleen]

On Wed, Jan 09, 2008 at 12:24:00PM -0800, Jim Keniston wrote:
> On Wed, 2008-01-09 at 00:28 +0100, Andi Kleen wrote:
> > > I have no problem with that, but if we want to make it buildable as a
> > > module, the call to get_kprobe() needs to be replaced with some other
> > > gcc-inline-defeating mechanism, or we need to export get_probe().  I
> > 
> > It's still unclear where noinline does not work (do you have details on that? 
> > It sounds a little dubious) ...
> 
> Here's a simplified version of a module we've used to gauge kprobes
> performance.  On my system (i386, 2.6.23-rc8 at the moment, gcc version
> 4.1.2), the module calls the (empty) probed function (probeme) niter
> times, but reports zero probe hits -- indicating probeme was inlined
> even though it was declared noinline.

Yes indeed looks like a gcc bug. Have you reported it?

-Andi
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