Re: [PATCH v2 1/2] mm/slub: optimize alloc/free fastpath by removing preemption on/off

[Steven Rostedt]

On Thu, 15 Jan 2015 21:57:58 -0600 (CST)
Christoph Lameter <cl@xxxxxxxxx> wrote:

> > I get:
> >
> > 		mov    %gs:0x18(%rax),%rdx
> >
> > Looks to me that %gs is used.
> 
> %gs is used as a segment prefix. That does not add significant cycles.
> Retrieving the content of %gs and loading it into another register
> would be expensive in terms of cpu cycles.

OK, maybe that's what I saw in my previous benchmarks. Again, that was
a while ago.

-- Steve
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