[Devel] [PATCH rh7] ve: Add interface for @start_timespec and @real_start_timespec adjustmen

[Cyrill Gorcunov]

On Tue, Feb 09, 2016 at 01:29:56PM +0300, Vladimir Davydov wrote:
> > 
> > Yes. We take current values then substract the @real_[start_]timespec
> > and return it. IOW they are just monotonic|boottime clocks.
> 
> Then I think we should name these files accordingly to avoid confusion.
> ve.clock_{monotonic,boottime} probably.

It was named so in pcs6, so I tried to preserve naming. But sure I
can rename, that's not a problem.

> > > This looks weird to me. Wouldn't it be better if we returned the
> > > timespec as is?
> > 
> > No, we have to account real total_sleep_time the container
> > has on the node, because when you close the lid the total
> > sleep time will increse but @real_start_timespec won't
> > as far as I can say and this gonna be wrong.
> 
> But you can always calculate the difference in userspace, like
> (CLOCK_BOOTTIME - ve.real_start_timespec), no?

No I fear not. Look, the calculation of how long container has been
uptime is fully up to the kernel, the @real_[start_]timespec is
not update by the kernel during clock ticks (this is completely
done in timekeeper code).

Vladimir, maybe I misunderstand you, could you please provide
the pseudocode how you imagine it could work? I mean without
in-kernel time normalization. I suspect I miss something obvious.