Re: [PATCH] x86 alternatives : fix LOCK_PREFIX race with preemptiblekernel and CPU hotplug

[H. Peter Anvin]

Andi Kleen wrote:
> > So, unless these calculus are completely bogus, the difference between the nop
> > and the DS case seems not to be statistically significant.
>
> My understanding was that the nops only make a measurable difference in the 
> -pg/mcount/ftrace patched out case where every function call starts with a 5
> byte nop.
>
> Presumably function calls are much more common than lock prefix operations.

Yeah, although the LOCK prefix was measurable.

	-hpa
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