Re: [RFC][PATCH 2/2] Reduced NTP rework (part 2)

From: Roman Zippel
Date: Tue Sep 27 2005 - 11:37:41 EST


Hi,

On Thu, 22 Sep 2005, john stultz wrote:

> +
> + /* calculate the total continuous ppm adjustment */
> + total_sppm = time_freq; /* already shifted by SHIFT_USEC */
> + total_sppm += offset_adj_ppm << SHIFT_USEC;
> + total_sppm += tick_adj_ppm << SHIFT_USEC;
> + total_sppm += singleshot_adj_ppm << SHIFT_USEC;
> }

I'm not sure, why you still need this.
As I already said, I don't think you need to change the kernel NTP model.
This means in particular that the NTP time is still incremented in fixed
intervals (although it's not necessary to do it at HZ frequency).
I showed you how to do most of the calculation, so I'm a little confused,
why the above is still used.

In general I would prefer to see the introduction of the timesource
abstraction, which will first replace the arch callbacks do_gettimeofday/
do_settimeofday.

bye, Roman
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