[Qemu-devel] [RFC] kvm: export host NUMA info to guest's scheduler

[Liu Ping Fan <kernelfans@gmail.com>]

Currently, the guest can not know the NUMA info of the vcpu, which will
result in performance drawback. For example:
  Supposing vcpu-a on nodeA, vcpu-b on nodeB, when load balance,
the tasks' pull and push between these vcpus will cost more. But
unfortunately, currently, the guest is just blind to this.

So here is the idea to solve it.
  Export host numa info through guest's sched domain to its scheduler.
  So the guest's lb will consider the cost.

These patches include:
For guest:
  0001-sched-add-virt-sched-domain-for-the-guest.patch
  0002-sched-add-virt-domain-device-s-driver.patch
For host:
  0001-kvm-collect-vcpus-numa-info-for-guest-s-scheduler.patch  
  0001-Qemu-add-virt-sched-domain-device.patch


Please give some comments and suggestion.

Thanks and regards,
pingfan