On Fri, 2007-08-17 at 12:49 -0700, Paul E. McKenney wrote:

quoted

quoted

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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