/* * Register a shared memory area from which the guest may obtain its own * runstate information without needing to execute a hypercall. * Notes: * 1. The registered address may be virtual or physical or guest handle, * depending on the platform. Virtual address or guest handle should be * registered on x86 systems. * 2. Only one shared area may be registered per VCPU. The shared area is * updated by the hypervisor each time the VCPU is scheduled. Thus * runstate.state will always be RUNSTATE_running and * runstate.state_entry_time will indicate the system time at which the * VCPU was last scheduled to run. * @extra_arg == pointer to vcpu_register_runstate_memory_area structure. */