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SubjectRe: ordered memory access
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>>>>> "Andrea" == Andrea Arcangeli <andrea@suse.de> writes:

Andrea> On 30 Sep 1999, Jes Sorensen wrote:
>> atomic_foo() should be ordered, at least that the idea behind it as

Andrea> It isn't. Also the atomic_inc/dec and set_bit clear_bit
Andrea> aren't.

Andrea> Only test_and_*_bit and atomic_dec_and_test enforce ordering
Andrea> between previous and following code.

Aren't according to what architecture? Some architectures can only
implement these by using a spin lock, thus they will certainly ensure
ordering. My point here is, should we specify these functions to
guarantee ordering, yes or no?

Intuitively I think it makes sense to do so, and I doubt it will be a
performance hit at all, but I am just guessing here.

Jes

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