This patch completes the implementation of the SCHED_ISO scheduling policy. This splits the SCHED_ISO policy into two discrete policies which are the unprivileged counterparts of SCHED_RR and SCHED_FIFO, calling them SCHED_ISO_RR and SCHED_ISO_FIFO. When an unprivileged user calls for a real time task they are downgraded to their SCHED_ISO counterparts. This patch also adds full priority support to the isochronous scheduling policies. Their range is the same size as the range available to MAX_USER_RT_PRIO but their effective priority is lower than any privileged real time tasks. The priorities as seen to userspace would appear as: 0 -> 39 SCHED_NORMAL -100 -> -1 Isochronous -200 -> -101 Real time Signed-off-by: Con Kolivas