Transparent huge pages are allocated with __GFP_MOVABLE, and can end up in CMA memory blocks. Transparent huge pages also have most of the infrastructure in place to allow migration. However, a few pieces were missing, causing THP migration to fail when attempting to use CMA to allocate 1GB hugepages. With these patches in place, THP migration from CMA blocks seems to work, both for anonymous THPs and for tmpfs/shmem THPs. v2: - addressed comments by Vlastimil Babka and Zi Yan Rik van Riel (2): mm,compaction,cma: add alloc_contig flag to compact_control mm,thp,compaction,cma: allow THP migration for CMA allocations mm/compaction.c | 16 +++++++++------- mm/internal.h | 1 + mm/page_alloc.c | 7 +++++-- 3 files changed, 15 insertions(+), 9 deletions(-) -- 2.24.1
