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    SubjectRe: [tip:x86/asm] x86: Speed up ___preempt_schedule*() by using THUNK helpers
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    On Fri, Oct 3, 2014 at 2:56 PM, Andy Lutomirski <luto@amacapital.net> wrote:
    >
    > Is this thing missing a flags or cc clobber:
    >
    > # define __preempt_schedule() asm ("call ___preempt_schedule")

    Yes, it should probably have a cc clobber. Although I think thet gcc
    actually assumes all asms clobber flags on x86, so it shouldn't
    matter.

    > Is this all just to make the call sequence for preempt_schedule shorter?

    Not so much the call sequence, but the code around the call - not
    havign to spill live registers etc. But yes.

    Linus


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