From mboxrd@z Thu Jan  1 00:00:00 1970
From: Arjan van de Ven <arjan@infradead.org>
Subject: Re: [PATCH 0/24] make atomic_read() behave consistently across all
	architectures
Date: Fri, 17 Aug 2007 12:49:00 -0700
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Cc: Chris Friesen <cfriesen@nortel.com>,
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	Satyam Sharma <satyam@infradead.org>,
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	Ilpo Jarvinen <ilpo.jarvinen@helsinki.fi>,
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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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