ticks_to_secs
prop_control = bps_to_internal(ticks_to_secs(prop_control)); /* in BT-1 */
sp->lastdel = ticks_to_secs(GRANULARITY*cl->cl_lastdel);
sp->busylength = ticks_to_secs(1000*delay_diff(now, cl->idletime));
cl->cl_avgdel += ticks_to_secs(GRANULARITY*cl->cl_lastdel);
#define invsecs_to_invticks(x) ticks_to_secs(x)