Re: [PATCH] N1int for interactivity

Zwane Mwaikambo (
Tue, 15 Jul 2003 03:00:43 -0400 (EDT)

On Mon, 14 Jul 2003, Andrew Morton wrote:

> > base = monotonic_base;
> > - read_unlock_irq(&monotonic_lock);
> > + read_unlock_irqrestore(&monotonic_lock, flags);
> >
> > /* Read the Time Stamp Counter */
> Why do we need to take a global lock here? Can't we use
> get_cycles() or something?

I think that'll break even on some x86 boxes if we used get_cycles. I do
wonder however why we need that lock, i see x86/64 uses seqlock at least.
Although i can't vouch for whether that would have an adverse affect here.
I presume Stultz would know.

> Have all the other architectures been reviewed to see if they need this
> change?

No one else appears to have monotonic_clock, this would break every other
arch out there.

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