Re: [PATCH] scheduler: fix x86 regression in native_sched_clock

[Nick Piggin]

On Friday 07 December 2007 22:17, Ingo Molnar wrote:
> * Nick Piggin <nickpiggin@xxxxxxxxxxxx> wrote:
> > > ah, printk_clock() still uses sched_clock(), not jiffies. So it's
> > > not the jiffies counter that goes back and forth, it's sched_clock()
> > > - so this is a printk timestamps anomaly, not related to jiffies. I
> > > thought we have fixed this bug in the printk code already:
> > > sched_clock() is a 'raw' interface that should not be used directly
> > > - the proper interface is cpu_clock(cpu).
> >
> > It's a single CPU box, so sched_clock() jumping would still be
> > problematic, no?
>
> sched_clock() is an internal API - the non-jumping API to be used by
> printk is cpu_clock().

You know why sched_clock jumps when the TSC frequency changes, right?

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