These compaction cleanups are split out from the huge page allocator
series[1], as requested by reviewer feedback.

Against current mm-stable.

[1] https://lore.kernel.org/linux-mm/20230418191313.268131-1-hannes@cmpxchg.org/

 include/linux/compaction.h     | 96 ++----------------------------------------------------------------------------------------------
 include/trace/events/mmflags.h |  4 ++--
 mm/compaction.c                | 62 ++++++++++++++++++++++++++++++++++----------------------------
 mm/page_alloc.c                | 57 ++++++++++++++++++++-------------------------------------
 mm/vmscan.c                    | 27 ++++++++++++++-------------
 5 files changed, 72 insertions(+), 174 deletions(-)