From mboxrd@z Thu Jan  1 00:00:00 1970
From: Avi Kivity <avi@redhat.com>
Subject: Re: [PATCH 08/31] nVMX: Fix local_vcpus_link handling
Date: Tue, 17 May 2011 18:11:40 +0300
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References: <1305575004-nyh@il.ibm.com> <201105161948.p4GJm1as001742@rice.haifa.ibm.com> <20110517131918.GA3809@amt.cnet> <4DD27998.1040105@redhat.com> <20110517143532.GA2490@fermat.math.technion.ac.il>
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Cc: Marcelo Tosatti <mtosatti@redhat.com>, kvm@vger.kernel.org,
	gleb@redhat.com
To: "Nadav Har'El" <nyh@math.technion.ac.il>
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On 05/17/2011 05:35 PM, Nadav Har'El wrote:
>
>>> What about having a per-CPU VMCS list instead of per-CPU vcpu list?
>> Perhaps even easier (avoids duplication):
>>
>> struct raw_vmcs {
>>      u32 revision_id;
>>      u32 abort;
>>      char data[0];
>> };
>>
>> struct vmcs {
>>      struct raw_vmcs *raw_vmcs;
>>      struct list_head local_vmcs_link;
>> };
>>
>> struct vcpu_vmx {
>>      ...
>>      struct vmcs *vmcs;  /* often points at l1_vmcs */
>>      struct vmcs l1_vmcs;
>>      ...
>> };
>>
>> static DEFINE_PER_CPU(struct list_head, vmcss_on_cpu);
> This is an interesting suggestion. My initial plan was to do something similar
> to this, and I agree it could have been nicer code, but I had to change it
> after bumping into too many obstacles.
>
> For example, currently, vmclear_local_vcpus() not only VMCLEARs the vmcss,
> it also sets vmx->vcpu.cpu = -1, xmv->launched=0 for the vcpus holding these
> VMCSs.  If we had only a list of VMCSs, how can we mark the vcpus as being not
> currently loaded (cpu=-1)?
>

->launched and ->cpu simply move into struct vmcs.