We presently skip regions with hugepages entirely when trying to do contiguous page allocation. Instead, if hugepage migration is enabled, consider regions with hugepages smaller than the requested allocation. Compaction `isolate_migrate_pages_block()` already expects requests with hugepages to originate from alloc_contig, and hugetlb code also does a migratable check when isolating in `folio_isolate_hugetlb()`. Suggested-by: David Hildenbrand Signed-off-by: Gregory Price --- mm/page_alloc.c | 15 +++++++++++++-- 1 file changed, 13 insertions(+), 2 deletions(-) diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 600d9e981c23..da2e65bf63e3 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -7048,8 +7048,19 @@ static bool pfn_range_valid_contig(struct zone *z, unsigned long start_pfn, if (PageReserved(page)) return false; - if (PageHuge(page)) - return false; + if (PageHuge(page)) { + unsigned int order; + + if (!IS_ENABLED(CONFIG_ARCH_ENABLE_HUGEPAGE_MIGRATION)) + return false; + + /* Don't consider moving same size/larger pages */ + page = compound_head(page); + order = compound_order(page); + if ((order >= MAX_PAGE_ORDER) || + (nr_pages < (1 << order))) + return false; + } } return true; } -- 2.51.0