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    SubjectRe: [RFC 00/17] Pile o' entry stack changes
    On Wed, Sep 6, 2017 at 3:16 PM, Andi Kleen <andi@firstfloor.org> wrote:
    > Andy Lutomirski <luto@kernel.org> writes:
    >>
    >> - Lots of people (Linus included) have asked to convert the entry
    >> code to pop registers on exit instead of movqing them off the
    >> stack. This makes a bunch of progress in that direction.
    >
    > You should benchmark it on Atoms. Likely it's a regression there
    > because they don't have the special PUSH/POP acceleration.

    I'm not entirely sure this is a worthwhile reason. Atom will lose a
    few cycles due to POP throughput, but there's a lot less decode
    bandwidth needed and we save a cache line or two.

    --Andy

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