Messages in this thread | | | Date | Wed, 19 Dec 2012 10:28:29 -0800 | From | John Stultz <> | Subject | Re: [PATCH] Round the calculated scale factor in set_cyc2ns_scale() |
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On 12/05/2012 06:16 AM, Bernd Faust wrote: > During some experiments with an external clock (in a FPGA), we saw that > the TSC clock drifted approx. 2.5ms per second. > > This drift was caused by the current way of calculating the scale. > In our case cpu_khz had a value of 3292725. This resulted in a scale > value of 310. But when doing the calculation by hand it shows that the > actual value is 310.9886188491, so a value of 311 would be more precise. > > With this change the value is rounded. > > Signed-off-by: Bernd Faust <berndfaust@gmail.com>
Thanks for sending this in! I've queued it, but because I was slow here, it will have to wait for 3.9.
Sorry for the delay, and thanks again! -john
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