Messages in this thread | | | Date | Wed, 9 Jan 2008 16:55:15 -0800 | From | Arjan van de Ven <> | Subject | Re: Replacement for page fault notifiers? |
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On Thu, 10 Jan 2008 01:47:16 +0100 Andi Kleen <andi@firstfloor.org> wrote:
> Arjan van de Ven <arjan@infradead.org> writes: > > > > 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. > > That would assume that your mmio area has a struct page. In most PCs > the ones in the PCI hole don't >
so you also call the function for all traps on pages without struct page; that should be extremely rare anyway, and the mmio_trace code can then look the page up.
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