... instead, look them up statically based on the page type. Maybe in the future we want a registration interface? At least for now, it can be easily handled using the two page types that actually support page migration.
The remaining usage of page->mapping is to flag such pages as actually being movable (having movable_ops), which we will change next. Reviewed-by: Zi Yan <z...@nvidia.com> Reviewed-by: Lorenzo Stoakes <lorenzo.stoa...@oracle.com> Reviewed-by: Harry Yoo <harry....@oracle.com> Signed-off-by: David Hildenbrand <da...@redhat.com> --- include/linux/balloon_compaction.h | 2 +- include/linux/migrate.h | 14 ++------------ include/linux/zsmalloc.h | 2 ++ mm/balloon_compaction.c | 1 - mm/compaction.c | 5 ++--- mm/migrate.c | 23 +++++++++++++++++++++++ mm/zpdesc.h | 5 ++--- mm/zsmalloc.c | 8 +++----- 8 files changed, 35 insertions(+), 25 deletions(-) diff --git a/include/linux/balloon_compaction.h b/include/linux/balloon_compaction.h index 9bce8e9f5018c..a8a1706cc56f3 100644 --- a/include/linux/balloon_compaction.h +++ b/include/linux/balloon_compaction.h @@ -92,7 +92,7 @@ static inline void balloon_page_insert(struct balloon_dev_info *balloon, struct page *page) { __SetPageOffline(page); - __SetPageMovable(page, &balloon_mops); + __SetPageMovable(page); set_page_private(page, (unsigned long)balloon); list_add(&page->lru, &balloon->pages); } diff --git a/include/linux/migrate.h b/include/linux/migrate.h index e04035f70e36f..6aece3f3c8be8 100644 --- a/include/linux/migrate.h +++ b/include/linux/migrate.h @@ -104,23 +104,13 @@ static inline int migrate_huge_page_move_mapping(struct address_space *mapping, #endif /* CONFIG_MIGRATION */ #ifdef CONFIG_COMPACTION -void __SetPageMovable(struct page *page, const struct movable_operations *ops); +void __SetPageMovable(struct page *page); #else -static inline void __SetPageMovable(struct page *page, - const struct movable_operations *ops) +static inline void __SetPageMovable(struct page *page) { } #endif -static inline -const struct movable_operations *page_movable_ops(struct page *page) -{ - VM_WARN_ON_ONCE_PAGE(!page_has_movable_ops(page), page); - - return (const struct movable_operations *) - ((unsigned long)page->mapping - PAGE_MAPPING_MOVABLE); -} - #ifdef CONFIG_NUMA_BALANCING int migrate_misplaced_folio_prepare(struct folio *folio, struct vm_area_struct *vma, int node); diff --git a/include/linux/zsmalloc.h b/include/linux/zsmalloc.h index 13e9cc5490f71..f3ccff2d966cd 100644 --- a/include/linux/zsmalloc.h +++ b/include/linux/zsmalloc.h @@ -46,4 +46,6 @@ void zs_obj_read_end(struct zs_pool *pool, unsigned long handle, void zs_obj_write(struct zs_pool *pool, unsigned long handle, void *handle_mem, size_t mem_len); +extern const struct movable_operations zsmalloc_mops; + #endif diff --git a/mm/balloon_compaction.c b/mm/balloon_compaction.c index e4f1a122d786b..2a4a649805c11 100644 --- a/mm/balloon_compaction.c +++ b/mm/balloon_compaction.c @@ -253,6 +253,5 @@ const struct movable_operations balloon_mops = { .isolate_page = balloon_page_isolate, .putback_page = balloon_page_putback, }; -EXPORT_SYMBOL_GPL(balloon_mops); #endif /* CONFIG_BALLOON_COMPACTION */ diff --git a/mm/compaction.c b/mm/compaction.c index 41fd6a1fe9a33..348eb754cb227 100644 --- a/mm/compaction.c +++ b/mm/compaction.c @@ -114,11 +114,10 @@ static unsigned long release_free_list(struct list_head *freepages) } #ifdef CONFIG_COMPACTION -void __SetPageMovable(struct page *page, const struct movable_operations *mops) +void __SetPageMovable(struct page *page) { VM_BUG_ON_PAGE(!PageLocked(page), page); - VM_BUG_ON_PAGE((unsigned long)mops & PAGE_MAPPING_MOVABLE, page); - page->mapping = (void *)((unsigned long)mops | PAGE_MAPPING_MOVABLE); + page->mapping = (void *)(PAGE_MAPPING_MOVABLE); } EXPORT_SYMBOL(__SetPageMovable); diff --git a/mm/migrate.c b/mm/migrate.c index e307b142ab41a..fde6221562399 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -43,6 +43,8 @@ #include <linux/sched/sysctl.h> #include <linux/memory-tiers.h> #include <linux/pagewalk.h> +#include <linux/balloon_compaction.h> +#include <linux/zsmalloc.h> #include <asm/tlbflush.h> @@ -51,6 +53,27 @@ #include "internal.h" #include "swap.h" +static const struct movable_operations *page_movable_ops(struct page *page) +{ + VM_WARN_ON_ONCE_PAGE(!page_has_movable_ops(page), page); + + /* + * If we enable page migration for a page of a certain type by marking + * it as movable, the page type must be sticky until the page gets freed + * back to the buddy. + */ +#ifdef CONFIG_BALLOON_COMPACTION + if (PageOffline(page)) + /* Only balloon compaction sets PageOffline pages movable. */ + return &balloon_mops; +#endif /* CONFIG_BALLOON_COMPACTION */ +#if defined(CONFIG_ZSMALLOC) && defined(CONFIG_COMPACTION) + if (PageZsmalloc(page)) + return &zsmalloc_mops; +#endif /* defined(CONFIG_ZSMALLOC) && defined(CONFIG_COMPACTION) */ + return NULL; +} + /** * isolate_movable_ops_page - isolate a movable_ops page for migration * @page: The page. diff --git a/mm/zpdesc.h b/mm/zpdesc.h index 5763f36039736..6855d9e2732d8 100644 --- a/mm/zpdesc.h +++ b/mm/zpdesc.h @@ -152,10 +152,9 @@ static inline struct zpdesc *pfn_zpdesc(unsigned long pfn) return page_zpdesc(pfn_to_page(pfn)); } -static inline void __zpdesc_set_movable(struct zpdesc *zpdesc, - const struct movable_operations *mops) +static inline void __zpdesc_set_movable(struct zpdesc *zpdesc) { - __SetPageMovable(zpdesc_page(zpdesc), mops); + __SetPageMovable(zpdesc_page(zpdesc)); } static inline void __zpdesc_set_zsmalloc(struct zpdesc *zpdesc) diff --git a/mm/zsmalloc.c b/mm/zsmalloc.c index b12250e219bb7..4aaff7c26ea96 100644 --- a/mm/zsmalloc.c +++ b/mm/zsmalloc.c @@ -1685,8 +1685,6 @@ static void lock_zspage(struct zspage *zspage) #ifdef CONFIG_COMPACTION -static const struct movable_operations zsmalloc_mops; - static void replace_sub_page(struct size_class *class, struct zspage *zspage, struct zpdesc *newzpdesc, struct zpdesc *oldzpdesc) { @@ -1709,7 +1707,7 @@ static void replace_sub_page(struct size_class *class, struct zspage *zspage, set_first_obj_offset(newzpdesc, first_obj_offset); if (unlikely(ZsHugePage(zspage))) newzpdesc->handle = oldzpdesc->handle; - __zpdesc_set_movable(newzpdesc, &zsmalloc_mops); + __zpdesc_set_movable(newzpdesc); } static bool zs_page_isolate(struct page *page, isolate_mode_t mode) @@ -1819,7 +1817,7 @@ static void zs_page_putback(struct page *page) { } -static const struct movable_operations zsmalloc_mops = { +const struct movable_operations zsmalloc_mops = { .isolate_page = zs_page_isolate, .migrate_page = zs_page_migrate, .putback_page = zs_page_putback, @@ -1882,7 +1880,7 @@ static void SetZsPageMovable(struct zs_pool *pool, struct zspage *zspage) do { WARN_ON(!zpdesc_trylock(zpdesc)); - __zpdesc_set_movable(zpdesc, &zsmalloc_mops); + __zpdesc_set_movable(zpdesc); zpdesc_unlock(zpdesc); } while ((zpdesc = get_next_zpdesc(zpdesc)) != NULL); } -- 2.49.0