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    SubjectRe: [PATCH] mm: clear 1G pages with streaming stores on x86
    On Mon, Mar 16, 2020 at 03:19:55PM +0300, Kirill A. Shutemov wrote:
    > On Mon, Mar 16, 2020 at 11:18:56AM +0100, Michal Hocko wrote:
    > > While this might be true, isn't that easily solveable by the existing
    > > ALTERNATIVE and cpu features framework. Can we have a feature bit to
    > > tell that movnti is worthwile for large data copy routines. Probably
    > > something for x86 maintainers.
    >
    > It still need somody to test which approach is better for the CPU.
    > See X86_FEATURE_REP_GOOD.

    How about inverting the sense of the bit? Set it on Broadwell-and-
    earlier CPUs, where it definitely improves performance by a huge amount,
    and new microarches can set it if it still outperforms rep mov?

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