Re: [RFC] time: xtime_lock is held too long

Eric Dumazet
2011-05-06T17:09:45Z

Le vendredi 06 mai 2011 à 18:59 +0200, Andi Kleen a écrit :
> On Fri, May 06, 2011 at 12:18:27PM +0200, Thomas Gleixner wrote:

> If that code path shows up in profiling. Only the timer interrupt
> did so far.
>
> > That's the completely wrong aproach, really. If stuff takes too long,
> > then we need to tackle it at the root of the problem and not solve it
> > by sprinkling magic prefetches all over the place.
>
> If you have a better way to make it faster please share it.
>

Unless I am very mistaken, it cannot explain my original report of up to
24.000 instructions waiting in ktime_get()

BTW, how many consecutive prefetch() a cpu can 'store/execute' before
throwing away hints ?