Re: Locking comment on shrink_caches()

Alan Cox (alan@lxorguk.ukuu.org.uk)
Wed, 26 Sep 2001 17:40:15 +0100 (BST)


> Ahh, that's a cpu bug -- one my athlons don't suffer from.
>
> Your Athlons may handle exclusive cache line acquisition more
> efficiently (due to memory subsystem performance) but it still
> does cost something.

On an exclusive line on Athlon a lock cycle is near enough free, its
just an ordering constraint. Since the line is in E state no other bus
master can hold a copy in cache so the atomicity is there. Ditto for newer
Intel processors
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