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SubjectRe: [PATCH tip:x86/mm 1/3] x86: A fast way to check capabilities of the current cpu
Hello,

On Wed, Mar 30, 2011 at 08:58:23AM -0700, H. Peter Anvin wrote:
> >> Add this_cpu_has() which determines if the current cpu has a certain
> >> ability using a segment prefix and a bit test operation.
> >
> >
> > Hmm: if the CPU capability is really tested in a performance critical
> > path, wouldn't it even be better to just use static_branch() now?
> >
>
> We have static_cpu_has() for this specific purpose (it actually predates
> static_branch()).

These patches have performance benefits but I don't think it would be
noticeable. I think it's more of code cleanup.

Thanks.

--
tejun


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