From 637fc7e479a60ae55357c0e3ffeca5a475ef5733 Mon Sep 17 00:00:00 2001 From: Christoph Lameter Date: Mon, 23 Apr 2007 14:41:09 -0700 Subject: page migration: fix NR_FILE_PAGES accounting NR_FILE_PAGES must be accounted for depending on the zone that the page belongs to. If we replace the page in the radix tree then we may have to shift the count to another zone. Suggested-by: Ethan Solomita Cc: Martin Bligh Signed-off-by: Christoph Lameter Signed-off-by: Andrew Morton Signed-off-by: Greg Kroah-Hartman --- mm/migrate.c | 15 ++++++++++++++- 1 file changed, 14 insertions(+), 1 deletion(-) (limited to 'mm') diff --git a/mm/migrate.c b/mm/migrate.c index e9b161bde95..4372d6b313a 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -297,7 +297,7 @@ static int migrate_page_move_mapping(struct address_space *mapping, void **pslot; if (!mapping) { - /* Anonymous page */ + /* Anonymous page without mapping */ if (page_count(page) != 1) return -EAGAIN; return 0; @@ -333,6 +333,19 @@ static int migrate_page_move_mapping(struct address_space *mapping, */ __put_page(page); + /* + * If moved to a different zone then also account + * the page for that zone. Other VM counters will be + * taken care of when we establish references to the + * new page and drop references to the old page. + * + * Note that anonymous pages are accounted for + * 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); + write_unlock_irq(&mapping->tree_lock); return 0; -- cgit v1.2.3-18-g5258