Allow the user to request only a specific subset of statistics.
This can be useful when working on a feature or optimization that is
known to affect that statistic.
Example:
(qemu) info stats vcpu halt_poll_fail_ns
provider: kvm
halt_poll_fail_ns (cumulative, ns): 0
In case multiple providers have the same statistic, the provider can be
specified too:
(qemu) info stats vcpu halt_poll_fail_ns kvm
provider: kvm
halt_poll_fail_ns (cumulative, ns): 0
Extracted from a patch by Mark Kanda.
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>