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SubjectRe: SMP syncronization on AMD processors (broken?)
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On Thu, 2005-10-06 at 17:05 +0400, Kirill Korotaev wrote:
> Hello Linus, Andrew and others,
>
> Please help with a not simple question about spin_lock/spin_unlock on
> SMP archs. The question is whether concurrent spin_lock()'s should
> acquire it in more or less "fair" fashinon or one of CPUs can starve any
> arbitrary time while others do reacquire it in a loop.

spinlocks are designed to not be fair. or rather are allowed to not be.
If you want them to be fair on x86 you need at minimum to put a
cpu_relax() in your busy loop...


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