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    SubjectRe: [tip:x86/mm] x86/mm/tlb: Make lazy TLB mode lazier
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    > On Jul 18, 2018, at 2:23 PM, Peter Zijlstra <peterz@infradead.org> wrote:
    >
    > On Wed, Jul 18, 2018 at 01:22:19PM -0400, Rik van Riel wrote:
    >>> On Jul 18, 2018, at 12:00 PM, Peter Zijlstra <peterz@infradead.org> wrote:
    >
    >>> Also, I don't suppose you've looked at the paravirt instances of
    >>> flush_tlb_other() ? They don't elide the flushes because of lazy.
    >>
    >> Let me look at those now :)
    >
    > <snip xen>
    >
    >> kvm_flush_tlb_other takes out preempted VCPUs from the flush mask,
    >> before calling native_flush_tlb_others, so it should get the optimization
    >> automatically.
    >
    > Ah, ok. I wasn't entirely sure the new lazy was purely for the idle
    > case. But yes, the KVM paravirt thing should get the idle case right.
    >
    Not just idle, but also running in kernel threads like ksoftirqd,
    kworker, kswapd, etc. However, kvm_flush_tlb_other calls
    native_flush_tlb_other, so it should get that optimization automatically
    from my patch series.

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