Re: [PATCH v4 2/4] pps: Drop the !NO_HZ_COMMON dependency from NTP_PPS
From: Rodolfo Giometti
Date: Tue Sep 29 2026 - 07:48:48 EST
Hi David,
On 29/09/2026 11:32, David Woodhouse wrote:
When second_overflow() is delivering skew, timekeeping_max_deferment()
should trigger a wakeup at the end of the second to ensure that the
skew gets recalculated — rather than leaving it active indefinitely.
Please put this fix in the series before 2/4, as for the tick_length
one.
So the results at https://david.woodhou.se/ntptest-r64/tickless/ need
to be redone, but you can take a look and shout if you want me to
change what I'm capturing or how I'm doing it.
What you capture is fine for me: the adjtimex state (offset, jitter,
stabil, errcnt) plus the per-pulse phase are what I wanted to see.
Two questions for the rerun:
- wouldn't it be better to also have the tickful baseline with the same
board, the same GPS and the same pulse period, so the numbers can be
compared directly?
- since typical PPS sources deliver 1 Hz, don't you think it would be
better to also do one run with the timepulse at 1 Hz?
Ciao,
Rodolfo
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