Re: [PATCH v6 2/3] KVM: dynamic halt_poll_ns adjustment

From	Wanpeng Li <wanpeng.li@hotmail.com>
Newsgroups	linux.kernel
Subject	Re: [PATCH v6 2/3] KVM: dynamic halt_poll_ns adjustment
Date	2015-09-03 11:00 +0200
Message-ID	<q4yxc-74k-5@gated-at.bofh.it> (permalink)
References	(1 earlier) <q4aOg-6Sb-41@gated-at.bofh.it> <q4kDU-4f5-9@gated-at.bofh.it> <q4lJE-5Mh-9@gated-at.bofh.it> <q4lTj-5Xp-1@gated-at.bofh.it> <q4xhM-5mN-1@gated-at.bofh.it>
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On 9/3/15 3:31 PM, Paolo Bonzini wrote:
>
> On 02/09/2015 21:23, David Matlack wrote:
>> I actually wasn't thinking about vcpu->halt_poll_ns though. If
>> single_task_running() breaks us out of the loop we will "goto out" instead
>> of scheduling. My suspicion is this will cause us to loop calling
>> kvm_vcpu_block and starve the waiting task (at least until need_resched()),
>> which would break the "only hog the cpu when idle" aspect of halt-polling.
> That's definitely a bug, yes.

Ok, I will send out v7 to fix this in this sunday since there is 
vacation in my country currently.

Regards,
Wanpeng Li

>
> Paolo

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Thread

[PATCH v6 2/3] KVM: dynamic halt_poll_ns adjustment Wanpeng Li <wanpeng.li@hotmail.com> - 2015-09-02 09:40 +0200
  Re: [PATCH v6 2/3] KVM: dynamic halt_poll_ns adjustment David Matlack <dmatlack@google.com> - 2015-09-02 20:10 +0200
    Re: [PATCH v6 2/3] KVM: dynamic halt_poll_ns adjustment Paolo Bonzini <pbonzini@redhat.com> - 2015-09-02 21:20 +0200
      Re: [PATCH v6 2/3] KVM: dynamic halt_poll_ns adjustment David Matlack <dmatlack@google.com> - 2015-09-02 21:30 +0200
        Re: [PATCH v6 2/3] KVM: dynamic halt_poll_ns adjustment Paolo Bonzini <pbonzini@redhat.com> - 2015-09-03 09:40 +0200
          Re: [PATCH v6 2/3] KVM: dynamic halt_poll_ns adjustment Wanpeng Li <wanpeng.li@hotmail.com> - 2015-09-03 11:00 +0200
    Re: [PATCH v6 2/3] KVM: dynamic halt_poll_ns adjustment Wanpeng Li <wanpeng.li@hotmail.com> - 2015-09-03 11:30 +0200
      Re: [PATCH v6 2/3] KVM: dynamic halt_poll_ns adjustment David Matlack <dmatlack@google.com> - 2015-09-03 18:10 +0200
        Re: [PATCH v6 2/3] KVM: dynamic halt_poll_ns adjustment Wanpeng Li <wanpeng.li@hotmail.com> - 2015-09-04 02:20 +0200
    Re: [PATCH v6 2/3] KVM: dynamic halt_poll_ns adjustment Wanpeng Li <wanpeng.li@hotmail.com> - 2015-09-04 03:20 +0200
      Re: [PATCH v6 2/3] KVM: dynamic halt_poll_ns adjustment Wanpeng Li <wanpeng.li@hotmail.com> - 2015-09-04 03:50 +0200

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