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    SubjectRe: [PATCH RFC V6 0/11] Paravirtualized ticketlocks
    * Srivatsa Vaddagiri <> [2012-03-31 09:37:45]:

    > The issue is with ticketlocks though. VCPUs could go into a spin w/o
    > a lock being held by anybody. Say VCPUs 1-99 try to grab a lock in
    > that order (on a host with one cpu). VCPU1 wins (after VCPU0 releases it)
    > and releases the lock. VCPU1 is next eligible to take the lock. If

    Sorry I meant to say "VCPU2 is next eligible ..."

    > that is not scheduled early enough by host, then remaining vcpus would keep
    > spinning (even though lock is technically not held by anybody) w/o making
    > forward progress.
    > In that situation, what we really need is for the guest to hint to host
    > scheduler to schedule VCPU1 early (via yield_to or something similar).

    s/VCPU1/VCPU2 ..

    - vatsa

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