On Thu, 20 Oct 2005, Steven Rostedt wrote:I think John has changed this, but in the "old" code if ntp was correcting the clock such that less than TICK_NSEC was added on a tick, AND, the time was read just prior to this tick the get_offset code would return ~TICK_NSEC of offset which would mean that a read right after the tick might be less than the one just prior to the tick. The error, however, would be in the nanosecond area (no where near a second). Again, as I said, I think John has changed this in is code so that the get_offset equivalent is also ntp corrected, thus eliminating the small back step.
Yes, but that shouldn't make a difference. NTP can slow down or speed up
the clock, but it should never make it go backwards. Especially for a
monotonic clock (as the name suggests).
It looks like if ntp_adj held a big negative number you might end up with a smaller output . ntp_adj is signed too .. I don't know how ntp_adj is set though .
I thought I remember George Anzinger speculating that ntp could cause the time to backwards , that's why I brought it up. Maybe if he's read he can clue us in ..