Re: [patch] clockevents_notify() need to be called with irq'senabled

From: Thomas Gleixner
Date: Fri Aug 14 2009 - 04:28:38 EST


On Fri, 14 Aug 2009, Suresh Siddha wrote:

> On Thu, 2009-08-13 at 23:05 -0700, Thomas Gleixner wrote:
> > On Thu, 13 Aug 2009, Suresh Siddha wrote:
> >
> > > From: Suresh Siddha <suresh.b.siddha@xxxxxxxxx>
> > > Subject: clockevents_notify() need to be called with irq's enabled
> > >
> > > Currently clockevents_notify() is called with interrupts enabled at some
> > > places and interrupts disabled at some other places.
> >
> > The only place I can see which calls clockevents_notify with
> > interrupts enabled is the hrtimer cpu hotplug code.
> >
> > I'm a bit wary to enable interrupts all over the place in sensitive
> > corners like ACPI idle code ...
> >
> > Why don't we just do the obvious and take clockevents_lock irqsave ?
>
> We didn't go that route because of the smp_call_function() in the cpu
> hotplug code. So we can't disable interrupts in that path.

Hmm, that's the tick_broadcast_on_off() stuff, right ?

Thanks,

tglx
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