mem-hotplug: alloc new page from a nearest neighbor node when mem-offline

mem-hotplug: alloc new page from a nearest neighbor node when mem-offline

If we offline a node, alloc the new page from a nearest neighbor node
instead of the current node or other remote nodes, because re-migrate is
a waste of time and the distance of the remote nodes is often very
large.

Also use GFP_HIGHUSER_MOVABLE to alloc new page if the zone is movable
zone or highmem zone.

Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Xishi Qiu <[email protected]>
Cc: Joonsoo Kim <[email protected]>
Cc: Vlastimil Babka <[email protected]>
Cc: Naoya Horiguchi <[email protected]>
Cc: David Rientjes <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>