Re: [Xen-devel] [PATCH 00/10] [PATCH RFC V2] Paravirtualized ticketlocks

[Linus Torvalds]

On Wed, Sep 28, 2011 at 8:55 AM, Jan Beulich <JBeulich@xxxxxxxx> wrote:
>
>> just use "lock xaddw" there too.
>
> I'm afraid that's not possible, as that might carry from the low 8 bits
> into the upper 8 ones, which must be avoided.

Oh damn, you're right. So I guess the "right" way to do things is with
cmpxchg, but some nasty mfence setup could do it too.

                          Linus
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/