From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Longpeng (Mike)" <longpeng2@huawei.com>
Subject: Re: A problem about optimize the kvm_vcpu_on_spin
Date: Mon, 14 Nov 2016 17:30:39 +0800
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To: Paolo Bonzini <pbonzini@redhat.com>
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On 2016/11/14 16:56, Paolo Bonzini wrote:

> 
>> Intel sdm vol3 ch-25.1.3 (p-1074) said: The “PAUSE-loop exiting” VM-execution
>> control is ignored if CPL > 0.
>>
>> Does this means that only guest's kernelspace spinlock could causes VMexit
>> due to "pause-loop exiting" ?
>>
>> If so, I think the kvm_vcpu_on_spin should selects a (currently not
>> running) vcpu which cpl=0 to boost, because the cpl>0 vcpus are not
>> the lock-holder. (suppose the guest isn't RT-linux)
>>
>> What about your opinion ?
> 
> Yes, that's a good idea!
> 
> Paolo


Thanks, I will send a RFC this week.

> 
> .
> 


-- 
Regards,
Longpeng(Mike)