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Subject: Re: [PATCH] break_lock forever broken
From: Arjan van de Ven <arjan@infradead.org>
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> 
> Yes that's the tradeoff. I just feel that the former may be better,
> especially because the latter can be timing dependant (so you may get
> things randomly "happening"), and the former is apparently very low
> overhead compared with the cost of taking the lock. Any numbers,
> anyone?

as I said, since the cacheline just got dirtied, the write is just half
a cycle which is so much in the noise that it really doesn't matter.