Messages in this thread | | | Date | Mon, 26 Oct 2009 07:18:32 -0700 | From | Arjan van de Ven <> | Subject | Re: Relicensing tracepoints and markers to Dual LGPL v2.1/GPL v2,headers to Dual BSD/GPL |
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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.
-- Arjan van de Ven Intel Open Source Technology Centre For development, discussion and tips for power savings, visit http://www.lesswatts.org
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