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SubjectRe: [PATCH] [LSM] Rework LSM hooks
>>>>> On Tue, 10 Aug 2004 16:31:12 -0400 (EDT), James Morris <jmorris@redhat.com> said:

James> On Tue, 10 Aug 2004, Chris Wright wrote:
>> Thanks, James. Since these are the only concrete numbers and
>> they are in the noise, I see no compelling reason to change to
>> unlikely().

James> There may be some way to make it ia64 specific. Is it a cpu
James> issue, or compiler?

I'm pretty sure the "unlikely()" part could be dropped with little/no
downside. The part that's relatively expensive (10 cycles when
mispredicted) is the indirect call. GCC doesn't handle this well on
ia64 and as a result, most indirect calls are mispredicted.

An alternative solution might be to have a call_likely() macro, where
you could predict the most likely target of an indirect call. Perhaps
that could help other platforms as well.

--david
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