From mboxrd@z Thu Jan  1 00:00:00 1970
From: Ingo Molnar <mingo@elte.hu>
Subject: Re: Software prefetching considered harmful
Date: Fri, 20 May 2011 01:34:00 +0200
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To: David Miller <davem@davemloft.net>
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* David Miller <davem@davemloft.net> wrote:

> So, to reiterate, I think you should kill all the list handling
> prefetches off.

Agreed.

> What we can do is say "for this specific list use, prefetch does
> in fact help".  And provide an interface for that.  I imagine there
> are things like inode dirty writeback or some dcache stuff that
> walks large lists and for which prefetch might be appropriate.

I think the best 'interface' for that is to open-code the prefetch()
right into the loop. This way it becomes well documented and very
visible as well.

Thanks,

	Ingo