Re: Ktimer / -rt9 (+custom) monotonic_clock going backwards.

[Ingo Molnar]

* Steven Rostedt <rostedt@xxxxxxxxxxx> wrote:

> > I just switched cycle_t to u64 and hackbench no longer makes the time go
> > backwards.
> >
> > John, would this cause any problems to keep cycle_t at s64?
> 
> I mean at u64.

ugh. There's both cycles_t and cycle_t. We should unify the two and it 
should be 64-bit. The faster systems get, the sooner the 32-bit counter 
overflows. 64-bit systems are keeping 32-bit compatibility for quite 
some time to come. So with an 8GHz CPU the 32-bit cycle_t would wrap in 
like 500 msecs, way too fast to rely on ... (even with a 4GHz CPUs it's 
only one second.)

i've made cycle_t u64 and have uploaded -rt14.

	Ingo
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