Re: [PATCH] convert cnt32_to_63 to inline

Peter Zijlstra
2008-11-11T22:38:17Z

On Tue, 2008-11-11 at 22:31 +0000, David Howells wrote:
> Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca> wrote:
>
> > @@ -52,18 +57,22 @@ unsigned long long sched_clock(void)
> > ...
> > + preempt_disable_notrace();
>
> Please, no! sched_clock() is called with preemption or interrupts disabled
> everywhere except from some debugging code (lock tracing IIRC). If you need
> to insert this preemption disablement somewhere, please insert it there. At
> least then sched_clock() will be called consistently.

Agreed. You could do a WARN_ON(!in_atomic); in sched_clock() depending
on DEBUG_PREEMPT or something to ensure this.