Nova Libvirt Configuring vcpus in specific order

Issue

Operator requests to allocate Physical CPUset (pcpu) in a specific order (Ascending or Descending)

Example

The present CPU pinning inside the VM is as follows:

root@compute-0 ~]# virsh dumpxml 5 |grep cpu
        <nova:vcpus>16</nova:vcpus>
  <vcpu placement='static'>16</vcpu>
  <cputune>
    <vcpupin vcpu='0' cpuset='1'/>
    <vcpupin vcpu='1' cpuset='2'/>
    <vcpupin vcpu='2' cpuset='3'/>
    <vcpupin vcpu='3' cpuset='4'/>
    <vcpupin vcpu='4' cpuset='5'/>
    <vcpupin vcpu='5' cpuset='6'/>
    <vcpupin vcpu='6' cpuset='7'/>
    <vcpupin vcpu='7' cpuset='8'/>
    <vcpupin vcpu='8' cpuset='19'/>
    <vcpupin vcpu='9' cpuset='20'/>
    <vcpupin vcpu='10' cpuset='21'/>
    <vcpupin vcpu='11' cpuset='22'/>
    <vcpupin vcpu='12' cpuset='23'/>
    <vcpupin vcpu='13' cpuset='24'/>
    <vcpupin vcpu='14' cpuset='25'/>
    <vcpupin vcpu='15' cpuset='26'/>

The requirement is as follows:

 <vcpupin vcpu='0' cpuset='26'/>
    <vcpupin vcpu='1' cpuset='25'/>
    <vcpupin vcpu='2' cpuset='24'/>
    <vcpupin vcpu='3' cpuset='23'/>
    <vcpupin vcpu='4' cpuset='22'/>
    <vcpupin vcpu='5' cpuset='21'/>
    <vcpupin vcpu='6' cpuset='20'/>
    <vcpupin vcpu='7' cpuset='19'/>
    <vcpupin vcpu='8' cpuset='8'/>
    <vcpupin vcpu='9' cpuset='7'/>
    <vcpupin vcpu='10' cpuset='6'/>
    <vcpupin vcpu='11' cpuset='5'/>
    <vcpupin vcpu='12' cpuset='4'/>
    <vcpupin vcpu='13' cpuset='3'/>
    <vcpupin vcpu='14' cpuset='2'/>
    <vcpupin vcpu='15' cpuset='1'/>