Re: [PATCH 1/5] Add functions producing system time given a backing counter value

On Wed, Jul 29, 2015 at 12:49:44PM +0200, Peter Zijlstra wrote:

This is still fuzzy, right? The hardware ART timestamp could be from
_before_ the NTP adjust; or the NTP adjust could happen while we do this
conversion and we'll take the retry loop.

In the original series, yes.
 

In both cases, the resulting value is computed using a different slope
than was in effect at the time of the stamp. With the end result being
slightly off from what it should be.

In Thomas' patch the get_ts() is meant to read fresh pairs of time
stamps from within the loop.


Thanks,
Richard