Re: [PATCHv3 linux-next] hrtimer: Add notifier when clock_was_setwas called

[Thomas Gleixner]

On Thu, 12 Sep 2013, John Stultz wrote:
> On Thu, Sep 12, 2013 at 6:44 AM, Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx> wrote:
> > On Thu, Sep 12, 2013 at 03:21:24PM +0200, Thomas Gleixner wrote:
> >>
> >> > (3): http://www.spinics.net/lists/netdev/msg245169.html
> >>
> >> Thanks for the explanation so far.
> >>
> >> What's still unclear to me is why these timeouts are bound to wall
> >> time in the first place.
> >>
> >> Is there any real reason why the key life time can't simply be
> >> expressed in monotonic time, e.g. N seconds after creation or M
> >> seconds after usage? Looking at the relevant RFCs I can't find any
> >> requirement for binding the life time to wall time.
> >>
> >> A life time of 10 minutes does not change when the wall clock is
> >> adjusted for whatever reasons. It's still 10 minutes and not some
> >> random result of the wall clock adjustments. But I might be wrong as
> >> usual :)
> >
> > Well we started out with straight timers.  It was changed because
> > people wanted IPsec SAs to expire after a suspect/resume which
> > AFAIK does not touch normal timers.
> 
> I'm not sure I've totally groked the specific need here, but if you're
> wanting a monotonic clockbase that includes suspend time, then you
> might checkout CLOCK_BOOTTIME.

Duh, completely forgot about that one. Sure that would avoid the whole
business.

Thanks,

	tglx
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