Linus was underwhelmed by the earlier compound mapcounts series: this series builds on top of it (as in next-20221117) to follow up on his suggestions - except rmap.c still using lock_page_memcg(), since I hesitate to steal the pleasure of deletion from Johannes. 1/3 mm,thp,rmap: subpages_mapcount of PTE-mapped subpages 2/3 mm,thp,rmap: subpages_mapcount COMPOUND_MAPPED if PMD-mapped 3/3 mm,thp,rmap: clean up the end of __split_huge_pmd_locked() Documentation/mm/transhuge.rst | 10 +- include/linux/mm.h | 65 +++++++---- include/linux/rmap.h | 12 +- mm/debug.c | 2 +- mm/huge_memory.c | 15 +-- mm/rmap.c | 213 ++++++++++------------------------- 6 files changed, 119 insertions(+), 198 deletions(-) Hugh
