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SubjectRe: [SisopIII-l] Re: [PATCH] fix #endif misplacement
Date
Hi,

Actually, the original code seems to be ok:

#ifndef CONFIG_NUMA
if (!use_tsc)
#endif
return (unsigned long long)jiffies * (1000000000 / HZ);

That is: on x86 we'll get into "#ifndef CONFIG_NUMA", and "if (!use_tsc)" will
be called, which should be the expected behaviour.

Maybe in your case the use_tsc flag was being set to 0 (bug in detection code
/ unsupported feature by the processor?), leading your code to ignore the TSC
and return the current time based on the current jiffies instead.

Lucas


On Friday 28 November 2003 14:39, Felipe W Damasio wrote:
> Hi Tim,
>
> Tim Schmielau wrote:
> > No, this is exactly what is intended: don't use the TSC on NUMA, use
> > jiffies instead.
>
> The patch didn't hurt this.
>
> > Look at the comment just above those lines.
>
> The patch doesn't uses jiffies indiscriminately: Only if we're on a
> NUMA system with !use_tsc.
>
> Otherwise (on x86 SMP, for example) we use rdtsc...which seems The
> Right Thing(tm). Hece move the #endif a bit down.
>
> Cheers
>
> Felipe
>
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