Re: [lustre-devel] [PATCH] staging: lustre: ldlm: pl_recalc time handling is wrong

[Arnd Bergmann <arnd@arndb.de>]

On Thursday, November 10, 2016 1:21:08 PM CET Greg Kroah-Hartman wrote:
> > 
> > the intention here is simply to have the console log keep the
> > same numbers as "date +%s" for absolute values. The patch that
> > James suggested converting everything to ktime_get_seconds()
> > would result in the same intervals that have always been there
> > (until I broke it by using time domains inconsistently), but
> > would mean we could use a u32 type for pl_recalc_time and
> > pl_recalc_period because that doesn't overflow until 136 years
> > after booting. (signed time_t overflows 68 years after 1970,
> > i.e 2038).
> 
> So, is this patch correct and should be merged to the tree, or not?
> 

No, I think it's wrong in a different way as before. After my
patch, there were six instances of ktime_get_real_seconds() and
three instances of ktime_get_seconds(), and that was wrong.

James's patch converts three of the six instances to
ktime_get_seconds(), which is equally wrong, just different.

We can either convert the six ktime_get_real_seconds()
to ktime_get_seconds(), or convert the four (one was added
in the meantime) ktime_get_seconds() to ktime_get_real_seconds().

I'll follow up with a patch for the latter as it is what I
had originally intended. We can also do what James intended
instead.

	Arnd