From: Naoya Horiguchi <[email protected]> This patch enables thp migration for memory hotremove. Stub definition of prep_transhuge_page() is added for CONFIG_TRANSPARENT_HUGEPAGE=n.
Signed-off-by: Naoya Horiguchi <[email protected]> --- include/linux/huge_mm.h | 3 +++ mm/memory_hotplug.c | 8 ++++++++ mm/page_isolation.c | 9 +++++++++ 3 files changed, 20 insertions(+) diff --git a/include/linux/huge_mm.h b/include/linux/huge_mm.h index 4ae156e..fe8766dc 100644 --- a/include/linux/huge_mm.h +++ b/include/linux/huge_mm.h @@ -174,6 +174,9 @@ static inline bool thp_migration_supported(void) static inline void prep_transhuge_page(struct page *page) {} #define transparent_hugepage_flags 0UL +static inline void prep_transhuge_page(struct page *page) +{ +} static inline int split_huge_page_to_list(struct page *page, struct list_head *list) { diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index b58906b..6abe898 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -1609,6 +1609,14 @@ do_migrate_range(unsigned long start_pfn, unsigned long end_pfn) if (isolate_huge_page(page, &source)) move_pages -= 1 << compound_order(head); continue; + } else if (thp_migration_supported() && PageTransHuge(page)) { + struct page *head = compound_head(page); + + pfn = page_to_pfn(head) + (1<<compound_order(head)) - 1; + if (compound_order(head) > PFN_SECTION_SHIFT) { + ret = -EBUSY; + break; + } } if (!get_page_unless_zero(page)) diff --git a/mm/page_isolation.c b/mm/page_isolation.c index 064b7fb..43ecdf6 100644 --- a/mm/page_isolation.c +++ b/mm/page_isolation.c @@ -294,6 +294,15 @@ struct page *alloc_migrate_target(struct page *page, unsigned long private, return alloc_huge_page_node(page_hstate(compound_head(page)), next_node_in(page_to_nid(page), node_online_map)); + else if (thp_migration_supported() && PageTransHuge(page)) { + struct page *thp; + + thp = alloc_pages(GFP_TRANSHUGE, HPAGE_PMD_ORDER); + if (!thp) + return NULL; + prep_transhuge_page(thp); + return thp; + } if (PageHighMem(page)) gfp_mask |= __GFP_HIGHMEM; -- 2.9.3
