The first gear in the whole AutoNUMA algorithm is knuma_scand. If
knuma_scand doesn't run AutoNUMA is a full bypass. If knuma_scand is
stopped, soon all other AutoNUMA gears will settle down too.
knuma_scand is the daemon that sets the pmd_numa and pte_numa and
allows the NUMA hinting page faults to start and then all other
actions follows as a reaction to that.
knuma_scand scans a list of "mm" and this is where we register and
unregister the "mm" into AutoNUMA for knuma_scand to scan them.
Signed-off-by: Andrea Arcangeli<aarcange@xxxxxxxxxx>