Re: [RFC PATCH 1/4] timekeeping: Remove xtime_remainder from ntp_error accumulation

[David Woodhouse]

On Tue, 2026-05-19 at 17:32 -0700, John Stultz wrote:
> On Tue, May 19, 2026 at 3:20 PM David Woodhouse <dwmw2@xxxxxxxxxxxxx>
> wrote:
> > 
> > On Tue, 2026-05-19 at 14:54 -0700, John Stultz wrote:
> > > 
> > > Its a nice analogy. Though if you're going to use it in your
> > > commit
> > > messages, it might be good to also add a comment to the
> > > timekeeping_adjustment() logic so there is an clear anchor to the
> > > code
> > > for folks who might not be as familiar with the detail.
> > > 
> > > 
> > > > > Also I'm not sure its very clear what you mean by
> > > > > "monotonicity clawback".
> > > > 
> > > > This is the offset applied by timekeeping_apply_adjustment() in
> > > > order
> > > > to ensure that the observed xtime remains monotonic when the
> > > > dithering
> > > > switches back from 'mult+1' to 'mult' and a consumer may have
> > > > seen a
> > > > 'later' time than it's about to set in {cycle_last,mult}.
> > > > 
> > > 
> > > This one I find less clarifying, but I do recognize "adjustments
> > > to
> > > the base xtime_nsec made when adjusting the multiplier due to
> > > unaccumulated cycles" is a mouthful.
> > > 
> > > The "xtime_nsec adjustment in timekeeping_apply_adjustment()" is
> > > probably easier/clearer?
> > 
> > How's this...
> > 
> > # Linux Timekeeping: Tick-Based Clock Discipline
> 
> So, I'm guessing given how fast you were to create this and how
> verbose it is, it was AI generated? (Apologies if I'm wrong here!)

It was originally, yes. But it wasn't that fast; I've had it open in
emacs for a week or so now. I had the AI write it for me so that I
could sanity-check it and refine my own understanding.

I trust the AI about as far as I can throw it.

> If so, do remember to use the Assisted-by tag.

Ack.

> I'll try to find some time to carefully review it, but while I
> appreciate the benefit of having a tool help write this, I'm not super
> excited about externalizing the cost of the review onto others.
> As careful review and feedback of an individuals work feels like
> investing in that collaborative effort, but doing the same for AI
> generated output just feels like a chore.

Oh, absolutely! I have actually done the first week's worth of saying
"no, that's complete horseshit. Tell me the truth" to it, as well as
refining the flow to make it read more coherently :)

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