Re: [PATCH] Turn rdmsr, rdtsc into inline functions, clarify names

On Mon, Aug 07, 2006 at 06:12:03PM +0200, Andi Kleen wrote:
> Vojtech Pavlik <[email protected]> writes:
> 
> > On Mon, Aug 07, 2006 at 05:57:14PM +0200, Andi Kleen wrote:
> > > > That way a driver could use
> > > > 
> > > > 	if (gtod_cpu_cycles_needed <= 500)
> > > > 		gettimeofday();
> > > > 	else
> > > > 		funky_fast_workaround();
> > > 
> > > Sounds like overengineering to me. I prefer something simple.
> > 
> > I could as well benchmark gettimeofday() in the gameport init.
> 
> Except you can't because the only way to benchmark it would
> be to use gettimeofday already and then you don't know
> how much is overhead and what is the real time.
 
I run it for 1/10th of a second in a loop and see how many iterations
I've done.  That's enough to check if its fast enough to use in the
gameport routine. Less than 50k iterations and I can't use it.

-- 
Vojtech Pavlik
Director SuSE Labs
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• References:
  • Re: [PATCH] Turn rdmsr, rdtsc into inline functions, clarify names
    • From: Dmitry Torokhov <[email protected]>
  • Re: [PATCH] Turn rdmsr, rdtsc into inline functions, clarify names
    • From: Andi Kleen <[email protected]>
  • Re: [PATCH] Turn rdmsr, rdtsc into inline functions, clarify names
    • From: Vojtech Pavlik <[email protected]>
  • Re: [PATCH] Turn rdmsr, rdtsc into inline functions, clarify names
    • From: Andi Kleen <[email protected]>
  • Re: [PATCH] Turn rdmsr, rdtsc into inline functions, clarify names
    • From: Vojtech Pavlik <[email protected]>
  • Re: [PATCH] Turn rdmsr, rdtsc into inline functions, clarify names
    • From: Andi Kleen <[email protected]>
  • Re: [PATCH] Turn rdmsr, rdtsc into inline functions, clarify names
    • From: Andreas Mohr <[email protected]>
  • Re: [PATCH] Turn rdmsr, rdtsc into inline functions, clarify names
    • From: Andi Kleen <[email protected]>
  • Re: [PATCH] Turn rdmsr, rdtsc into inline functions, clarify names
    • From: Vojtech Pavlik <[email protected]>
  • Re: [PATCH] Turn rdmsr, rdtsc into inline functions, clarify names
    • From: Andi Kleen <[email protected]>

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