diff options
Diffstat (limited to 'mm/migrate.c')
| -rw-r--r-- | mm/migrate.c | 55 |
1 files changed, 34 insertions, 21 deletions
diff --git a/mm/migrate.c b/mm/migrate.c index a88c12f2235..808f8abb1b8 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -30,6 +30,7 @@ #include <linux/mempolicy.h> #include <linux/vmalloc.h> #include <linux/security.h> +#include <linux/backing-dev.h> #include <linux/memcontrol.h> #include <linux/syscalls.h> #include <linux/hugetlb.h> @@ -307,10 +308,12 @@ static inline bool buffer_migrate_lock_buffers(struct buffer_head *head, * 2 for pages with a mapping * 3 for pages with a mapping and PagePrivate/PagePrivate2 set. */ -static int migrate_page_move_mapping(struct address_space *mapping, +int migrate_page_move_mapping(struct address_space *mapping, struct page *newpage, struct page *page, struct buffer_head *head, enum migrate_mode mode) { + struct zone *oldzone, *newzone; + int dirty; int expected_count = 0; void **pslot; @@ -321,6 +324,9 @@ static int migrate_page_move_mapping(struct address_space *mapping, return MIGRATEPAGE_SUCCESS; } + oldzone = page_zone(page); + newzone = page_zone(newpage); + spin_lock_irq(&mapping->tree_lock); pslot = radix_tree_lookup_slot(&mapping->page_tree, @@ -361,6 +367,13 @@ static int migrate_page_move_mapping(struct address_space *mapping, set_page_private(newpage, page_private(page)); } + /* Move dirty while page refs frozen and newpage not yet exposed */ + dirty = PageDirty(page); + if (dirty) { + ClearPageDirty(page); + SetPageDirty(newpage); + } + radix_tree_replace_slot(pslot, newpage); /* @@ -370,6 +383,9 @@ static int migrate_page_move_mapping(struct address_space *mapping, */ page_unfreeze_refs(page, expected_count - 1); + spin_unlock(&mapping->tree_lock); + /* Leave irq disabled to prevent preemption while updating stats */ + /* * If moved to a different zone then also account * the page for that zone. Other VM counters will be @@ -380,16 +396,23 @@ static int migrate_page_move_mapping(struct address_space *mapping, * via NR_FILE_PAGES and NR_ANON_PAGES if they * are mapped to swap space. */ - __dec_zone_page_state(page, NR_FILE_PAGES); - __inc_zone_page_state(newpage, NR_FILE_PAGES); - if (!PageSwapCache(page) && PageSwapBacked(page)) { - __dec_zone_page_state(page, NR_SHMEM); - __inc_zone_page_state(newpage, NR_SHMEM); + if (newzone != oldzone) { + __dec_zone_state(oldzone, NR_FILE_PAGES); + __inc_zone_state(newzone, NR_FILE_PAGES); + if (PageSwapBacked(page) && !PageSwapCache(page)) { + __dec_zone_state(oldzone, NR_SHMEM); + __inc_zone_state(newzone, NR_SHMEM); + } + if (dirty && mapping_cap_account_dirty(mapping)) { + __dec_zone_state(oldzone, NR_FILE_DIRTY); + __inc_zone_state(newzone, NR_FILE_DIRTY); + } } - spin_unlock_irq(&mapping->tree_lock); + local_irq_enable(); return MIGRATEPAGE_SUCCESS; } +EXPORT_SYMBOL(migrate_page_move_mapping); /* * The expected number of remaining references is the same as that @@ -460,20 +483,9 @@ void migrate_page_copy(struct page *newpage, struct page *page) if (PageMappedToDisk(page)) SetPageMappedToDisk(newpage); - if (PageDirty(page)) { - clear_page_dirty_for_io(page); - /* - * Want to mark the page and the radix tree as dirty, and - * redo the accounting that clear_page_dirty_for_io undid, - * but we can't use set_page_dirty because that function - * is actually a signal that all of the page has become dirty. - * Whereas only part of our page may be dirty. - */ - if (PageSwapBacked(page)) - SetPageDirty(newpage); - else - __set_page_dirty_nobuffers(newpage); - } + /* Move dirty on pages not done by migrate_page_move_mapping() */ + if (PageDirty(page)) + SetPageDirty(newpage); mlock_migrate_page(newpage, page); ksm_migrate_page(newpage, page); @@ -492,6 +504,7 @@ void migrate_page_copy(struct page *newpage, struct page *page) if (PageWriteback(newpage)) end_page_writeback(newpage); } +EXPORT_SYMBOL(migrate_page_copy); /************************************************************ * Migration functions |