[PATCH 0/5] KVM: Turn the vcpu array into an xarray

[Paolo Bonzini]

On 11/16/21 15:13, Juergen Gross wrote:
> On 05.11.21 20:20, Marc Zyngier wrote:
>> The kvm structure is pretty large. A large portion of it is the vcpu
>> array, which is 4kB on x86_64 and arm64 as they deal with 512 vcpu
>> VMs. Of course, hardly anyone runs VMs this big, so this is often a
>> net waste of memory and cache locality.
>>
>> A possible approach is to turn the fixed-size array into an xarray,
>> which results in a net code deletion after a bit of cleanup.
>>
>> This series is on top of the current linux/master as it touches the
>> RISC-V implementation. Only tested on arm64.
>>
>> Marc Zyngier (5):
>>    KVM: Move wiping of the kvm->vcpus array to common code
>>    KVM: mips: Use kvm_get_vcpu() instead of open-coded access
>>    KVM: s390: Use kvm_get_vcpu() instead of open-coded access
>>    KVM: x86: Use kvm_get_vcpu() instead of open-coded access
>>    KVM: Convert the kvm->vcpus array to a xarray
>>
>>   arch/arm64/kvm/arm.c           | 10 +---------
>>   arch/mips/kvm/loongson_ipi.c   |  4 ++--
>>   arch/mips/kvm/mips.c           | 23 ++---------------------
>>   arch/powerpc/kvm/powerpc.c     | 10 +---------
>>   arch/riscv/kvm/vm.c            | 10 +---------
>>   arch/s390/kvm/kvm-s390.c       | 26 ++++++--------------------
>>   arch/x86/kvm/vmx/posted_intr.c |  2 +-
>>   arch/x86/kvm/x86.c             |  9 +--------
>>   include/linux/kvm_host.h       |  7 ++++---
>>   virt/kvm/kvm_main.c            | 33 ++++++++++++++++++++++++++-------
>>   10 files changed, 45 insertions(+), 89 deletions(-)
>>
> 
> For x86 you can add my:
> 
> Tested-by: Juergen Gross <jgross at suse.com>

Heh, unfortunately x86 is the only one that needs a change in patch 4. 
I'll Cc you on my version.

Paolo