Re: [patch] x86, mm: pass in 'total' to __copy_from_user_*nocache()

From: Arjan van de Ven
Date: Sat Feb 28 2009 - 13:40:25 EST


On Sat, 28 Feb 2009 19:27:59 +0100
Ingo Molnar <mingo@xxxxxxx> wrote:

>
> OTOH, given how draconian non-temporal stores are, i'm leaning
> towards removing them from the x86 code altogether. If it matter
> to performance somewhere it can be reintroduced, based on really
> well backed up numbers.

I think that is mostly the right approach; O_DIRECT could be the
exception to that (because there we don't only wipe it from the cpu
cache due to DMA, it even gets wiped from the pagecache!).
But I can see that being too special of a case to care about in the
grand scheme of things (although the database people will now get upset
with me ;-)

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Arjan van de Ven Intel Open Source Technology Centre
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