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

Hi!

> > > > > Would not preempt_disable fix that?
> > > > 
> > > > Partially, but you still have other problems. Please just get rid
> > > > of it. Why do we have timer code in the kernel if you then chose
> > > > not to use it?
> > >  
> > > The problem is that gettimeofday() is not always fast. 
> > 
> > When it is not fast that means it is not reliable and then you're
> > also not well off using it anyways.
> 
> I assume you wanted to say "When gettimeofday() is slow, it means TSC is
> not reliable", which I agree with. 
> 
> But I need, in the driver, in the no-TSC case use i/o counting, not a
> slow but reliable method. And I can't say, from outside the timing
> subsystem, whether gettimeofday() is fast or slow.

do gettimeofday(); gettimeofday(); gettimeofday();, then compare the
result with gettimeofday(); inb(); gettimeofday(); ?

						Pavel
-- 
Thanks for all the (sleeping) penguins.
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• References:
  • Re: [PATCH] Turn rdmsr, rdtsc into inline functions, clarify names
    • From: Rusty Russell <[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: 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]>

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