Re: [PATCH] x86: printk_time to use tsc before cpu_clock is ready

[Ingo Molnar]

* Peter Zijlstra <a.p.zijlstra@xxxxxxxxx> wrote:

> On Wed, 2008-08-27 at 09:42 +0200, Ingo Molnar wrote:
> > * Yinghai Lu <yhlu.kernel@xxxxxxxxx> wrote:
> > 
> > > +static unsigned long long tsc_clock(int cpu)
> > > +{
> > > +	unsigned long long t;
> > > +
> > > +	rdtscll(t);
> > > +
> > > +	return t;
> > > +}
> > 
> > hm, i'm not sure i like the whole direction - this reintroduces 
> > printk_clock in essence.
> > 
> > how about initializing cpu_clock() sooner, so that printk timestamps 
> > start ticking as soon as possible?
> 
> which will make some archs quite unhappy iirc, see those arm and ia64 
> bugs I caused the other day.

that's OK - that still allows arches to start their clocks whenever they 
want to. But also add the possibility for architectures to initialize 
things even sooner.

	Ingo
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