Re: [Xen-devel] [PATCHv2 4/6] x86: provide xadd()

["Jan Beulich" <JBeulich@xxxxxxxx>]

>>> On 16.04.15 at 13:25, <tim@xxxxxxx> wrote:
> But also: AFAICS the GCC builtin __sync_fetch_and_add() does almost
> exactly this (the difference being that those are also compiler
> barriers where this is only a CPU barrier).  Should we be using it
> instead?

I'm afraid that's useful only from gcc 4.5.x onwards; earlier versions
(on x86 at least) simply generate a function call relying on a library to
implement it.

Jan


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