acrn-hypervisor/hypervisor/arch
dongshen 14fa9c563c hv: define posted interrupt IRQs/vectors
This is a preparation patch for adding support for VT-d PI
related vCPU scheduling.

ACRN does not support vCPU migration, one vCPU always runs on
the same pCPU, so PI's ndst is never changed after startup.

VCPUs of a VM won’t share same pCPU. So the maximum possible number
of VCPUs that can run on a pCPU is CONFIG_MAX_VM_NUM.

Allocate unique Activation Notification Vectors (ANV) for each vCPU
that belongs to the same pCPU, the ANVs need only be unique within each
pCPU, not across all vCPUs. This reduces # of pre-allocated ANVs for
posted interrupts to CONFIG_MAX_VM_NUM, and enables ACRN to avoid
switching between active and wake-up vector values in the posted
interrupt descriptor on vCPU scheduling state changes.

A total of CONFIG_MAX_VM_NUM consecutive IRQs/vectors are reserved
for posted interrupts use.

The code first initializes vcpu->arch.pid.control.bits.nv dynamically
(will be added in subsequent patch), the other code shall use
vcpu->arch.pid.control.bits.nv instead of the hard-coded notification vectors.

Rename some functions:
  apicv_post_intr --> apicv_trigger_pi_anv
  posted_intr_notification --> handle_pi_notification
  setup_posted_intr_notification --> setup_pi_notification

Tracked-On: #4506
Signed-off-by: dongshen <dongsheng.x.zhang@intel.com>
Reviewed-by: Eddie Dong <eddie.dong@Intel.com>
2020-04-15 13:47:22 +08:00
..
x86 hv: define posted interrupt IRQs/vectors 2020-04-15 13:47:22 +08:00