Re: [PATCH 0/24] make atomic_read() behave consistently across allarchitectures

From: Arjan van de Ven
Date: Fri Aug 17 2007 - 15:54:26 EST



On Fri, 2007-08-17 at 12:49 -0700, Paul E. McKenney wrote:
> > > What about reading values modified in interrupt handlers, as in your
> > > "random" case? Or is this a bug where the user of atomic_read() is
> > > invalidly expecting a read each time it is called?
> >
> > the interrupt handler case is an SMP case since you do not know
> > beforehand what cpu your interrupt handler will run on.
>
> With the exception of per-CPU variables, yes.

if you're spinning waiting for a per-CPU variable to get changed by an
interrupt handler... you have bigger problems than "volatile" ;-)

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