Messages in this thread | | | Date | Thu, 31 Jul 2014 11:25:37 +0200 | From | Paolo Bonzini <> | Subject | Re: [PATCH] KVM: nVMX: nested TPR shadow/threshold emulation |
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Il 31/07/2014 10:03, Wanpeng Li ha scritto: >> One thing: >> >>> + if (nested_cpu_has(vmcs12, CPU_BASED_TPR_SHADOW)) >>> + vmcs_write32(TPR_THRESHOLD, vmcs12->tpr_threshold); >> >> I think you can just do this write unconditionally, since most >> hypervisors will enable this. Also, you probably can add the tpr > > What will happen if a hypervisor doesn't enable it? I make it more > cleaner in version two.
TPR_THRESHOLD will be likely written as zero, but the processor will never use it anyway. It's just a small optimization because nested_cpu_has(vmcs12, CPU_BASED_TPR_SHADOW) will almost always be true.
Paolo
>> threshold field to the read-write fields for shadow VMCS. > > Agreed. > > Regards, > Wanpeng Li
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