ssb_state
struct ssb_state *shared_state;
static DEFINE_PER_CPU(struct ssb_state, ssb_state);
struct ssb_state *st = this_cpu_ptr(&ssb_state);
if (!per_cpu(ssb_state, cpu).shared_state)
st->shared_state = per_cpu(ssb_state, cpu).shared_state;
struct ssb_state *st = this_cpu_ptr(&ssb_state);