Re: x86 - cpu_relax - why nop vs. pause?

From: Arjan van de Ven
Date: Sun Feb 07 2010 - 13:31:00 EST


On Sun, 07 Feb 2010 12:28:51 -0500
Michael Breuer <mbreuer@xxxxxxxxxx> wrote:

> I did search and noticed some old discussions. Looking at both Intel
> and AMD documentation, it would seem that PAUSE is the preferred
> instruction within a spin lock. Further, both Intel and AMD
> specifications state that the instruction is backward compatible with
> older x86 processors.
>

that's odd....

rep nop and pause ought to be the same...



--
Arjan van de Ven Intel Open Source Technology Centre
For development, discussion and tips for power savings,
visit http://www.lesswatts.org
--
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/