Re: [PATCH RFC] perf: x86: Improve accuracy of perf/sched clock

From: Peter Zijlstra
Date: Fri Jul 24 2015 - 11:03:18 EST


On Fri, Jul 24, 2015 at 04:39:55PM +0300, Adrian Hunter wrote:
> @@ -251,17 +253,17 @@ static void set_cyc2ns_scale(unsigned long cpu_khz, int cpu)
> rdtscll(tsc_now);
> ns_now = cycles_2_ns(tsc_now);
>
> - /*
> - * Compute a new multiplier as per the above comment and ensure our
> - * time function is continuous; see the comment near struct
> - * cyc2ns_data.
> - */

I'd leave this comment, but update the one this refers to; esp. the bit
that explains why 10.

Also, I think you can remove the definition of CYC2NS_SCALE_FACTOR.

Other than that, seems like a good idea.
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