This reverts commit 7db8889a (mm: have order > 0 compaction start off
where it left) and commit de74f1cc (mm: have order > 0 compaction start
near a pageblock with free pages). These patches were a good idea and
tests confirmed that they massively reduced the amount of scanning but
the implementation is complex and tricky to understand. A later patch
will cache what pageblocks should be skipped and reimplements the
concept of compact_cached_free_pfn on top for both migration and
free scanners.
Signed-off-by: Mel Gorman <mgorman@xxxxxxx>