Re: 2.6.9-rc1-mm4 sparc reiser4 build broken - undefinedatomic_sub_and_test

[Roman Zippel]

Hi,

On Mon, 13 Sep 2004, Tonnerre wrote:

> On Mon, Sep 13, 2004 at 06:03:28PM +0200, Roman Zippel wrote:
> > +#define atomic_add_and_test(i,v) (atomic_add_return((i), (v)) == 0)
> > +#define atomic_sub_and_test(i,v) (atomic_sub_return((i), (v)) == 0)
> 
> This is no longer atomic, is it? I mean, there's no guarantee that the
> atomic_add_return   and   the    comparison   are   executed   without
> interruption, is there?

Only the read/write access needs to be atomic, when the comparison happens 
is irrelevant.

bye, Roman
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