Re: [PATCH] Fix next_timer_interrupt() for hrtimer

[Tony Lindgren <tony@atomide.com>]

* john stultz <johnstul@us.ibm.com> [060223 16:37]:
> On Thu, 2006-02-23 at 16:26 -0800, Tony Lindgren wrote:
> > +	tv = ktime_to_timespec(event);
> > +
> > +	/* Assume read xtime_lock is held, so we can't use getnstimeofday() */
> > +	sec = xtime.tv_sec;
> > +	nsec = xtime.tv_nsec;
> > +	while (unlikely(nsec >= NSEC_PER_SEC)) {
> > +		nsec -= NSEC_PER_SEC;
> > +		++sec;
> > +	}
> > +	tv.tv_sec = sec;
> > +	tv.tv_nsec = nsec;
> 
> Er, I think you should be able to nest readers. Thus getnstimeofday()
> should be safe to call. Or is the comment wrong and you are assuming a
> write lock is held?

Oops, it's a write lock as next_timer_interrupt gets called from
arch/*/time.c.

Tony