Re: [PATCH 4/4] KVM: x86: track actual TSC frequency from the timekeeper struct

From	Paolo Bonzini <pbonzini@redhat.com>
Newsgroups	linux.kernel
Subject	Re: [PATCH 4/4] KVM: x86: track actual TSC frequency from the timekeeper struct
Date	2016-02-19 17:00 +0100
Message-ID	<r3VDk-7j5-19@gated-at.bofh.it> (permalink)
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On 19/02/2016 15:12, Marcelo Tosatti wrote:
> 
>> >  I need to check how often the timekeeper updates the parameters.
> I'd assume once every tick, the function is called (the notifier).
> 
> But you can optimize that away by only updating the TSC frequency
> when mult/shift are updated, which should be much rarer.

Yes, exactly.  That would still not be rate limiting.

But worst case it can be a lot of adjustments, up to HZ per second...

Paolo

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Re: [PATCH 4/4] KVM: x86: track actual TSC frequency from the  timekeeper struct Marcelo Tosatti <mtosatti@redhat.com> - 2016-02-16 15:10 +0100
  Re: [PATCH 4/4] KVM: x86: track actual TSC frequency from the  timekeeper struct Marcelo Tosatti <mtosatti@redhat.com> - 2016-02-16 15:30 +0100
    Re: [PATCH 4/4] KVM: x86: track actual TSC frequency from the  timekeeper struct Paolo Bonzini <pbonzini@redhat.com> - 2016-02-16 18:10 +0100
      Re: [PATCH 4/4] KVM: x86: track actual TSC frequency from the  timekeeper struct Marcelo Tosatti <mtosatti@redhat.com> - 2016-02-19 15:20 +0100
        Re: [PATCH 4/4] KVM: x86: track actual TSC frequency from the  timekeeper struct Paolo Bonzini <pbonzini@redhat.com> - 2016-02-19 17:00 +0100

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