Currently the vcpu_affinity[] array fixes the vCPU to pCPU mapping.
While the new cpu_affinity_bitmap doesn't explicitly sepcify this
mapping, instead, it implicitly assumes that vCPU0 maps to the pCPU
with lowest pCPU ID, vCPU1 maps to the second lowest pCPU ID, and
so on.
This makes it possible for post-launched VM to run vCPUs on a subset of
these pCPUs only, and not all of them.
acrn-dm may launch post-launched VMs with the current approach: indicate
VM UUID and hypervisor launches all VCPUs from the PCPUs that are masked
in cpu_affinity_bitmap.
Also acrn-dm can choose to launch the VM on a subset of PCPUs that is
defined in cpu_affinity_bitmap. In this way, acrn-dm must specify the
subset of PCPUs in the CREATE_VM hypercall.
Additionally, with this change, a guest's vcpu_num can be easily calculated
from cpu_affinity_bitmap, so don't assign vcpu_num in vm_configuration.c.
Tracked-On: #4616
Signed-off-by: Zide Chen <zide.chen@intel.com>
Acked-by: Eddie Dong <eddie.dong@intel.com>
9150284ca7