kvmppc_dec_expires_host_tb
if (now > kvmppc_dec_expires_host_tb(vcpu)) {
dec_nsec = tb_to_ns(kvmppc_dec_expires_host_tb(vcpu) - now);
if (now < kvmppc_dec_expires_host_tb(vcpu) &&
mtspr(SPRN_DEC, kvmppc_dec_expires_host_tb(vcpu) - *tb);
((tb < kvmppc_dec_expires_host_tb(vcpu)) ||