Replace read tick function pointers with the new hot-patched get_tick().
This optimizes the performance of functions such as: sched_clock()
Signed-off-by: NPavel Tatashin <pasha.tatashin@oracle.com>
Reviewed-by: NSteven Sistare <steven.sistare@oracle.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>