On Thu, Mar 18, 2021 at 07:05:49PM +0100, Paolo Bonzini wrote: > On 18/03/21 19:04, Marcelo Tosatti wrote: > > > > > > Not clear why this is necessary, if the choice was to not touch TSC page > > > at all, when invariant TSC is supported on the host... > > > > s/invariant TSC/TSC scaling/ > > > > > Ah, OK, this is not for the migration with iTSC on destination case, > > > but any call to kvm_gen_update_masterclock, correct? > > Yes, any update can be racy. > > Paolo Which makes an unrelated KVM_REQ_MASTERCLOCK_UPDATE -> kvm_gen_update_masterclock sequence to inadvertedly reduce performance a possibility, unless i am missing something. Ah, OK, it should be enabled again at KVM_REQ_CLOCK_UPDATE. Nevermind, then.
