Re: [PATCH RFC 0/6] Implement per-processor data areas for i386.

From: Andreas Mohr
Date: Sun Aug 27 2006 - 14:24:25 EST


Hi,

On Sun, Aug 27, 2006 at 08:04:38PM +0200, Andi Kleen wrote:
>
> > Something like that had to be done eventually about the inefficient
> > current_thread_info() mechanism,
>
> Inefficient? It's two fast instructions. I won't call that inefficient.

And that AGI stall?

> > I guess it's due to having tried that on an older installation with gcc 3.2,
> > which probably does less efficient opcode merging of current_thread_info()
> > requests compared to a current gcc version.
>
> gcc normally doesn't merge inline assembly at all.

Depends on use of volatile, right?

OK, so probably there was no merging of separate requests,
but opcode intermingling could have played a role.

Andreas Mohr
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