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Subject: Re: Replacement for page fault notifiers?
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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To: Arjan van de Ven <arjan@infradead.org>
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Date: Thu, 10 Jan 2008 11:56:47 +1100
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> I'm btw all in favor of making mmio tracing full fledged kernel infrastructure.
> This doesn't mean "notifier" imo; this means a real flag in the struct page,
> and then the page fault code can do
> 
> if (page->flags & FLAG_MMIO_TRACED)
> 	mmio_trace(page, regs, whatever..);
> 
> (probably surrounded by a CONFIG_ ifdef)
> THis is a TON lighter than a notifier chain, and actually what you want,
> you don't really want a notifier, you want a call back when a special kind of
> page is touched.
> 

Except that MMIO has no struct page's...

Cheers,
Ben.