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SubjectRe: spin_unlock optimization(i386)
Date

> In my opinion, relying on apparent ordering instead of enforcing it may
> lead to subtil race conditions. We may, for example, be victimized by some
> hardware erratum due to brain-deaded hardware optimizations, if we try to
> be clever when we should avoid to do so.
>
I agree, but
- Ingo molnar noticed a 4 % speed-up with lmbench - IMHO this means that we
should try hard to use the optimization.
- it's a CPU semaphore, ie a bad PCI card cannot cause any problems.
- both CPU's are very similar [Intel says that both should have the same
stepping, and the list of supported combinations with different steppings is
short]

--
Manfred




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