Re: Linux 2.6.32-rc1

Arjan van de Ven
2009-09-30T16:13:47Z

On Wed, 30 Sep 2009 17:57:25 +0200
Eric Dumazet <eric.dumazet@gmail.com> wrote:
>
> Note:
>
> lock; cmpxchg8b (%%esi)
>
> gives 4 bytes opcode : f0 0f c7 0e
> Because alternative (call cmpxchg8b_emu) uses 5 bytes, a nop will be
> added.
>
> Choosing ".byte 0xf0, 0x0f, 0xc7, 0x4e, 0x00" aka "lock cmpxchg8b
> 0x0(%esi)" is a litle bit better ?

doesn't matter normally.. nops fall out quickly in the execution path ;)

--
Arjan van de Ven Intel Open Source Technology Centre
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