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Date: Tue, 17 Jul 2012 14:01:48 +0530
From: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com>
Organization: IBM
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To: Avi Kivity <avi@redhat.com>
CC: "H. Peter Anvin" <hpa@zytor.com>, Thomas Gleixner <tglx@linutronix.de>,
        Marcelo Tosatti <mtosatti@redhat.com>, Ingo Molnar <mingo@redhat.com>,
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        S390 <linux-s390@vger.kernel.org>, Carsten Otte <cotte@de.ibm.com>,
        Christian Borntraeger <borntraeger@de.ibm.com>,
        KVM <kvm@vger.kernel.org>, chegu vinod <chegu_vinod@hp.com>,
        "Andrew M. Theurer" <habanero@linux.vnet.ibm.com>,
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        Srivatsa Vaddagiri <srivatsa.vaddagiri@gmail.com>,
        Joerg Roedel <joerg.roedel@amd.com>
Subject: Re: [PATCH RFC V4 2/3] kvm: Note down when cpu relax intercepted
 or pause loop exited
References: <20120716082445.23477.15128.sendpatchset@codeblue.in.ibm.com> <20120716082514.23477.23849.sendpatchset@codeblue.in.ibm.com> <5003E682.20909@redhat.com> <50044E58.60905@linux.vnet.ibm.com> <500520A8.50106@redhat.com>
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On 07/17/2012 01:52 PM, Avi Kivity wrote:
> On 07/16/2012 08:24 PM, Raghavendra K T wrote:
>> So are you saying allow vcpu to spin in non over-commit scenarios? So
>> that we avoid all yield_to etc...
>>
>> ( Or even in some other place where it is useful).
>
> When is yielding useful, if you're not overcommitted?
>

Right. There is no need to do yield_to when run queue has only one task.