lkml.org 
[lkml]   [2019]   [Oct]   [15]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
SubjectRe: [PATCH] KVM: X86: Make fpu allocation a common function
Date
Sean Christopherson <sean.j.christopherson@intel.com> writes:

> On Mon, Oct 14, 2019 at 06:58:49PM +0200, Vitaly Kuznetsov wrote:
>> Xiaoyao Li <xiaoyao.li@intel.com> writes:
>>
>> > They are duplicated codes to create vcpu.arch.{user,guest}_fpu in VMX
>> > and SVM. Make them common functions.
>> >
>> > No functional change intended.
>>
>> Would it rather make sense to move this code to
>> kvm_arch_vcpu_create()/kvm_arch_vcpu_destroy() instead?
>
> Does it make sense? Yes. Would it actually work? No. Well, not without
> other shenanigans.
>
> FPU allocation can't be placed after the call to .create_vcpu() becuase
> it's consumed in kvm_arch_vcpu_init(). FPU allocation can't come before
> .create_vcpu() because the vCPU struct itself hasn't been allocated.

A very theoretical question: why do we have 'struct vcpu' embedded in
vcpu_vmx/vcpu_svm and not the other way around (e.g. in a union)? That
would've allowed us to allocate memory in common code and then fill in
vendor-specific details in .create_vcpu().

--
Vitaly

\
 
 \ /
  Last update: 2019-10-15 12:55    [W:0.130 / U:0.440 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site