Re: [PATCH v2] KVM: halt-polling: poll if emulated lapic timer will fire soon

From	Paolo Bonzini <pbonzini@redhat.com>
Newsgroups	linux.kernel
Subject	Re: [PATCH v2] KVM: halt-polling: poll if emulated lapic timer will fire soon
Date	2016-05-19 17:00 +0200
Message-ID	<rAxAD-16l-41@gated-at.bofh.it> (permalink)
References	<rAwbv-kQ-3@gated-at.bofh.it> <rAwEx-vI-23@gated-at.bofh.it> <rAxAC-16l-29@gated-at.bofh.it>
Organization	linux.* mail to news gateway

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On 19/05/2016 16:52, Christian Borntraeger wrote:
>> > Would this work too and be simpler?
> Hmm, your patch does only fiddle with the grow/shrink logic (which might
> be a good idea independently of this change), but the original patch 
> actually takes into account that we have a guaranteed maximum time by a 
> wakeup timer - IOW we know exactly what the maximum poll time is.
> 

Yes, it's different.  The question is whether a 10us poll (40,000 clock
cycles) has an impact even if it's sometimes wrong.

Thanks,

Paolo

Thread

[PATCH v2] KVM: halt-polling: poll if emulated lapic timer will fire soon Wanpeng Li <kernellwp@gmail.com> - 2016-05-19 15:30 +0200
  Re: [PATCH v2] KVM: halt-polling: poll if emulated lapic timer will  fire soon Christian Borntraeger <borntraeger@de.ibm.com> - 2016-05-19 15:50 +0200
  Re: [PATCH v2] KVM: halt-polling: poll if emulated lapic timer will  fire soon Paolo Bonzini <pbonzini@redhat.com> - 2016-05-19 16:00 +0200
    Re: [PATCH v2] KVM: halt-polling: poll if emulated lapic timer will  fire soon Christian Borntraeger <borntraeger@de.ibm.com> - 2016-05-19 17:00 +0200
      Re: [PATCH v2] KVM: halt-polling: poll if emulated lapic timer will  fire soon Paolo Bonzini <pbonzini@redhat.com> - 2016-05-19 17:00 +0200
        Re: [PATCH v2] KVM: halt-polling: poll if emulated lapic timer will  fire soon Paolo Bonzini <pbonzini@redhat.com> - 2016-05-19 17:10 +0200
          Re: [PATCH v2] KVM: halt-polling: poll if emulated lapic timer will  fire soon Christian Borntraeger <borntraeger@de.ibm.com> - 2016-05-19 17:50 +0200
        Re: [PATCH v2] KVM: halt-polling: poll if emulated lapic timer will  fire soon Christian Borntraeger <borntraeger@de.ibm.com> - 2016-05-19 17:10 +0200
    Re: [PATCH v2] KVM: halt-polling: poll if emulated lapic timer will  fire soon Wanpeng Li <kernellwp@gmail.com> - 2016-05-24 04:50 +0200
  Re: [PATCH v2] KVM: halt-polling: poll if emulated lapic timer will  fire soon David Matlack <dmatlack@google.com> - 2016-05-19 20:10 +0200
    Re: [PATCH v2] KVM: halt-polling: poll if emulated lapic timer will  fire soon David Matlack <dmatlack@google.com> - 2016-05-19 20:40 +0200
      Re: [PATCH v2] KVM: halt-polling: poll if emulated lapic timer will  fire soon Yang Zhang <yang.zhang.wz@gmail.com> - 2016-05-20 04:10 +0200
        Re: [PATCH v2] KVM: halt-polling: poll if emulated lapic timer will  fire soon Wanpeng Li <kernellwp@gmail.com> - 2016-05-20 08:00 +0200
        Re: [PATCH v2] KVM: halt-polling: poll if emulated lapic timer will  fire soon David Matlack <dmatlack@google.com> - 2016-05-20 20:40 +0200
          Re: [PATCH v2] KVM: halt-polling: poll if emulated lapic timer will  fire soon Yang Zhang <yang.zhang.wz@gmail.com> - 2016-05-23 03:30 +0200
            Re: [PATCH v2] KVM: halt-polling: poll if emulated lapic timer will  fire soon David Matlack <dmatlack@google.com> - 2016-05-23 20:10 +0200
              Re: [PATCH v2] KVM: halt-polling: poll if emulated lapic timer will  fire soon Yang Zhang <yang.zhang.wz@gmail.com> - 2016-05-24 03:20 +0200
                Re: [PATCH v2] KVM: halt-polling: poll if emulated lapic timer will  fire soon David Matlack <dmatlack@google.com> - 2016-05-24 03:20 +0200
                Re: [PATCH v2] KVM: halt-polling: poll if emulated lapic timer will  fire soon Yang Zhang <yang.zhang.wz@gmail.com> - 2016-05-24 05:00 +0200

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