Messages in this thread | | | Date | Thu, 11 Sep 2003 17:42:10 +0100 | From | Matthew Wilcox <> | Subject | Re: Memory mapped IO vs Port IO |
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On Thu, Sep 11, 2003 at 06:31:36PM +0200, Andi Kleen wrote: > On Thu, 11 Sep 2003 17:25:04 +0100 > Matthew Wilcox <willy@debian.org> wrote: > > That's not true for MMIO writes which are posted. They should take > > no longer than a memory write. For MMIO reads and PIO reads & writes, > > you are, of course, correct. > > Even a memory write is tens to hundres of cycles.
So are mispredicted branches.
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