From 3417013e0d183be9b42d794082eec0ec1c5b5f15 Mon Sep 17 00:00:00 2001 From: "Matthew Wilcox (Oracle)" Date: Fri, 7 May 2021 07:28:40 -0400 Subject: [PATCH] mm/migrate: Add folio_migrate_mapping() Reimplement migrate_page_move_mapping() as a wrapper around folio_migrate_mapping(). Saves 193 bytes of kernel text. Signed-off-by: Matthew Wilcox (Oracle) Reviewed-by: Christoph Hellwig Reviewed-by: David Howells Acked-by: Vlastimil Babka --- include/linux/migrate.h | 2 ++ mm/folio-compat.c | 11 +++++++ mm/migrate.c | 85 +++++++++++++++++++++++++------------------------ 3 files changed, 57 insertions(+), 41 deletions(-) diff --git a/include/linux/migrate.h b/include/linux/migrate.h index c8077e9..58b3af6 100644 --- a/include/linux/migrate.h +++ b/include/linux/migrate.h @@ -57,6 +57,8 @@ extern int migrate_huge_page_move_mapping(struct address_space *mapping, struct page *newpage, struct page *page); extern int migrate_page_move_mapping(struct address_space *mapping, struct page *newpage, struct page *page, int extra_count); +int folio_migrate_mapping(struct address_space *mapping, + struct folio *newfolio, struct folio *folio, int extra_count); #else static inline void putback_movable_pages(struct list_head *l) {} diff --git a/mm/folio-compat.c b/mm/folio-compat.c index a374747..d883d96 100644 --- a/mm/folio-compat.c +++ b/mm/folio-compat.c @@ -4,6 +4,7 @@ * eventually. */ +#include #include #include @@ -48,3 +49,13 @@ void mark_page_accessed(struct page *page) folio_mark_accessed(page_folio(page)); } EXPORT_SYMBOL(mark_page_accessed); + +#ifdef CONFIG_MIGRATION +int migrate_page_move_mapping(struct address_space *mapping, + struct page *newpage, struct page *page, int extra_count) +{ + return folio_migrate_mapping(mapping, page_folio(newpage), + page_folio(page), extra_count); +} +EXPORT_SYMBOL(migrate_page_move_mapping); +#endif diff --git a/mm/migrate.c b/mm/migrate.c index bfb8ba4..0e408ee4 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -364,7 +364,7 @@ static int expected_page_refs(struct address_space *mapping, struct page *page) */ expected_count += is_device_private_page(page); if (mapping) - expected_count += thp_nr_pages(page) + page_has_private(page); + expected_count += compound_nr(page) + page_has_private(page); return expected_count; } @@ -377,74 +377,75 @@ static int expected_page_refs(struct address_space *mapping, struct page *page) * 2 for pages with a mapping * 3 for pages with a mapping and PagePrivate/PagePrivate2 set. */ -int migrate_page_move_mapping(struct address_space *mapping, - struct page *newpage, struct page *page, int extra_count) +int folio_migrate_mapping(struct address_space *mapping, + struct folio *newfolio, struct folio *folio, int extra_count) { - XA_STATE(xas, &mapping->i_pages, page_index(page)); + XA_STATE(xas, &mapping->i_pages, folio_index(folio)); struct zone *oldzone, *newzone; int dirty; - int expected_count = expected_page_refs(mapping, page) + extra_count; - int nr = thp_nr_pages(page); + int expected_count = expected_page_refs(mapping, &folio->page) + extra_count; + long nr = folio_nr_pages(folio); if (!mapping) { /* Anonymous page without mapping */ - if (page_count(page) != expected_count) + if (folio_ref_count(folio) != expected_count) return -EAGAIN; /* No turning back from here */ - newpage->index = page->index; - newpage->mapping = page->mapping; - if (PageSwapBacked(page)) - __SetPageSwapBacked(newpage); + newfolio->index = folio->index; + newfolio->mapping = folio->mapping; + if (folio_test_swapbacked(folio)) + __folio_set_swapbacked(newfolio); return MIGRATEPAGE_SUCCESS; } - oldzone = page_zone(page); - newzone = page_zone(newpage); + oldzone = folio_zone(folio); + newzone = folio_zone(newfolio); xas_lock_irq(&xas); - if (page_count(page) != expected_count || xas_load(&xas) != page) { + if (folio_ref_count(folio) != expected_count || + xas_load(&xas) != folio) { xas_unlock_irq(&xas); return -EAGAIN; } - if (!page_ref_freeze(page, expected_count)) { + if (!folio_ref_freeze(folio, expected_count)) { xas_unlock_irq(&xas); return -EAGAIN; } /* - * Now we know that no one else is looking at the page: + * Now we know that no one else is looking at the folio: * no turning back from here. */ - newpage->index = page->index; - newpage->mapping = page->mapping; - page_ref_add(newpage, nr); /* add cache reference */ - if (PageSwapBacked(page)) { - __SetPageSwapBacked(newpage); - if (PageSwapCache(page)) { - SetPageSwapCache(newpage); - set_page_private(newpage, page_private(page)); + newfolio->index = folio->index; + newfolio->mapping = folio->mapping; + folio_ref_add(newfolio, nr); /* add cache reference */ + if (folio_test_swapbacked(folio)) { + __folio_set_swapbacked(newfolio); + if (folio_test_swapcache(folio)) { + folio_set_swapcache(newfolio); + newfolio->private = folio_get_private(folio); } } else { - VM_BUG_ON_PAGE(PageSwapCache(page), page); + VM_BUG_ON_FOLIO(folio_test_swapcache(folio), folio); } /* Move dirty while page refs frozen and newpage not yet exposed */ - dirty = PageDirty(page); + dirty = folio_test_dirty(folio); if (dirty) { - ClearPageDirty(page); - SetPageDirty(newpage); + folio_clear_dirty(folio); + folio_set_dirty(newfolio); } - xas_store(&xas, newpage); - if (PageTransHuge(page)) { + xas_store(&xas, newfolio); + if (nr > 1) { int i; for (i = 1; i < nr; i++) { xas_next(&xas); - xas_store(&xas, newpage); + xas_store(&xas, newfolio); } } @@ -453,7 +454,7 @@ int migrate_page_move_mapping(struct address_space *mapping, * to one less reference. * We know this isn't the last reference. */ - page_ref_unfreeze(page, expected_count - nr); + folio_ref_unfreeze(folio, expected_count - nr); xas_unlock(&xas); /* Leave irq disabled to prevent preemption while updating stats */ @@ -472,18 +473,18 @@ int migrate_page_move_mapping(struct address_space *mapping, struct lruvec *old_lruvec, *new_lruvec; struct mem_cgroup *memcg; - memcg = page_memcg(page); + memcg = folio_memcg(folio); old_lruvec = mem_cgroup_lruvec(memcg, oldzone->zone_pgdat); new_lruvec = mem_cgroup_lruvec(memcg, newzone->zone_pgdat); __mod_lruvec_state(old_lruvec, NR_FILE_PAGES, -nr); __mod_lruvec_state(new_lruvec, NR_FILE_PAGES, nr); - if (PageSwapBacked(page) && !PageSwapCache(page)) { + if (folio_test_swapbacked(folio) && !folio_test_swapcache(folio)) { __mod_lruvec_state(old_lruvec, NR_SHMEM, -nr); __mod_lruvec_state(new_lruvec, NR_SHMEM, nr); } #ifdef CONFIG_SWAP - if (PageSwapCache(page)) { + if (folio_test_swapcache(folio)) { __mod_lruvec_state(old_lruvec, NR_SWAPCACHE, -nr); __mod_lruvec_state(new_lruvec, NR_SWAPCACHE, nr); } @@ -499,11 +500,11 @@ int migrate_page_move_mapping(struct address_space *mapping, return MIGRATEPAGE_SUCCESS; } -EXPORT_SYMBOL(migrate_page_move_mapping); +EXPORT_SYMBOL(folio_migrate_mapping); /* * The expected number of remaining references is the same as that - * of migrate_page_move_mapping(). + * of folio_migrate_mapping(). */ int migrate_huge_page_move_mapping(struct address_space *mapping, struct page *newpage, struct page *page) @@ -564,7 +565,7 @@ void migrate_page_states(struct page *newpage, struct page *page) if (PageMappedToDisk(page)) SetPageMappedToDisk(newpage); - /* Move dirty on pages not done by migrate_page_move_mapping() */ + /* Move dirty on pages not done by folio_migrate_mapping() */ if (PageDirty(page)) SetPageDirty(newpage); @@ -640,11 +641,13 @@ int migrate_page(struct address_space *mapping, struct page *newpage, struct page *page, enum migrate_mode mode) { + struct folio *newfolio = page_folio(newpage); + struct folio *folio = page_folio(page); int rc; - BUG_ON(PageWriteback(page)); /* Writeback must be complete */ + BUG_ON(folio_test_writeback(folio)); /* Writeback must be complete */ - rc = migrate_page_move_mapping(mapping, newpage, page, 0); + rc = folio_migrate_mapping(mapping, newfolio, folio, 0); if (rc != MIGRATEPAGE_SUCCESS) return rc; @@ -2470,7 +2473,7 @@ static void migrate_vma_collect(struct migrate_vma *migrate) * @page: struct page to check * * Pinned pages cannot be migrated. This is the same test as in - * migrate_page_move_mapping(), except that here we allow migration of a + * folio_migrate_mapping(), except that here we allow migration of a * ZONE_DEVICE page. */ static bool migrate_vma_check_page(struct page *page) -- 2.7.4