On Tue, Jul 16, 2013 at 1:49 AM, Linus Torvalds
<[email protected]> wrote:
> On Mon, Jul 15, 2013 at 10:28 AM, Geert Uytterhoeven
> <[email protected]> wrote:
>>
>> but the first one is non-trivial: using xchg() on atomic_t is a bit gross...
>
> It's also broken. There's no guarantee that an "atomic_t" is just a
> value. Now, the old sparc32 stuff (which hid lock bits in atomic_t)
> may be gone, but it's still the case that atomic_t may not actually
> work with xchg.
>
> (In *practice* it works on normal architectures, so I'm not saying
> that we don't have it, but it's a bug if we do).
>
> There are "atomic_xchg()" and "atomic_xchg64()" functions that are supported.
I'll send a patch to fix it.
>
> Linus
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
