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SubjectRe: Relicensing tracepoints and markers to Dual LGPL v2.1/GPL v2,headers to Dual BSD/GPL
On Mon, 26 Oct 2009 09:17:49 -0400
Pierre-Marc Fournier <pierre-marc.fournier@polymtl.ca> wrote:

> Ingo Molnar wrote:
> >
> > But i also disagree with it on a technical level: code duplication
> > is _bad_. Why does the code have to be duplicated in user-space
> > like that? I'd like Linux tracing code to be in the kernel repo.
> > Why isnt this done properly, as part of the kernel project - to
> > make sure it all stays in sync?
> >
>
> If you mean that this code should solely be used inside the kernel,
> then what you propose technically does not work. There is a very high
> cost to accessing kernel code from userspace.

yeah 100 cycles is insanely high, that's at least the equivalent of...
say one cache miss.


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Arjan van de Ven Intel Open Source Technology Centre
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