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    SubjectRe: [PATCH] local_irq_disable removal


    I was just trying to get an idea of the possible slow down if any, and for
    x86 I'm convinced that it's not a slowdown..

    Daniel

    On Sun, 12 Jun 2005, Zwane Mwaikambo wrote:

    > On Sat, 11 Jun 2005, Daniel Walker wrote:
    >
    > > Interesting .. So "cli" takes 7 cycles , "sti" takes 7 cycles. The current
    > > method does "lea" which takes 1 cycle, and "or" which takes 1 cycle. I'm
    > > not sure if there is any function call overhead .. So the soft replacment
    > > of cli/sti is 70% faster on a per instruction level .. So it's at least
    > > not any slower .. Does everyone agree on that?
    >
    > Well you also have to take into account the memory access, so it's not
    > always that straightforward.
    >
    > Zwane
    >
    >

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