Re: performance counter 20% error finding retired instruction count

[Ingo Molnar]

* Peter Zijlstra <a.p.zijlstra@xxxxxxxxx> wrote:

> On Wed, 2009-06-24 at 22:12 -0400, Vince Weaver wrote:
> > 
> > It's also nice to be able to skip the loader overhead, as the 
> > loader can change from system to system and makes it hard to 
> > compare counters across various machines.  Though it sounds like 
> > the perf utility isn't going to be supporting this anytime soon.
> 
> Feel free to contribute such if you think its important.

I'd be glad to review and test any resulting patches from Vince - 
and/or help out with pointers where to start and help out there's 
any roadblocks along the way.

The kernel side bits can be found in v2.6.31-rc1, in 
kernel/perf_counter.c, include/linux/perf_counter.h and 
arch/x86/kernel/cpu/perf_counter.c. We tried to keep the code as 
hackable as possible.

The tooling bits can be found in tools/perf/ in the kernel repo. 
builtin-stat.c contains the 'perf stat' bits.

Thanks,

	Ingo
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/