How do I set threads_policy on a flavor if I want to pin vcpu of a compute node with its thread sibling core ?

Issue

• For application performance reason, I would like to use vcpu pinning, specially threads_policy feature.
• For example, if there is host which has 2 socket cpu and 4core per socket and hyperthread enabled. (so the total logical core is 16)

 cpu0 : lcore0 1 2 3 8 9 10 11
 cpu1 : lcore4 5 6 7 12 13 14 15

• Then lcore0 and 8 are in same physical core, aka, thread sibling.
• If I want to set 4 vcpu in guest VM pin like below,

vcpu0 = lcore0
vcpu1 = lcore8
vcpu2 = lcore1
vcpu3 = lcore9

• what's shoud I do?
• I have currently set the hw:cpu_policy : dedicated in flavor extra_spec.