Re: [PATCH 2/3] ntp: add ADJ_SETOFFSET mode bit

From: Richard Cochran
Date: Tue Jan 04 2011 - 03:37:50 EST


On Mon, Jan 03, 2011 at 12:44:26PM -0800, John Stultz wrote:
> On Wed, 2010-12-29 at 05:47 +0900, Kuwahara,T. wrote:
> > I came up with this simple solution: "Just use ADJ_OFFSET as usual,
> > but don't forget to disable the kernel PLL."
>
> Again, this seems to be trying to add new functionality into a corner
> case of a existing mode.
>
> I don't like this because it makes testing and validating that the code
> is correct for its uses difficult. Especially given that a number of
> combinations of modes might be set at once. What happens to freq
> adjustments done at the same time as an ADJ_OFFSET - STA_PLL?

Where are the mode bits and their combinations documented, anyhow?

There are lot of papers on NTP, and I have not read them all, but I
don't recall having seen a precise and succinct decription of the
ntp_adjtime interface anywhere.

Thanks,
Richard
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