From 053837fce7aa79025ed57656855df09f80175527 Mon Sep 17 00:00:00 2001 From: Nick Piggin Date: Wed, 18 Jan 2006 17:42:27 -0800 Subject: [PATCH] mm: migration page refcounting fix Migration code currently does not take a reference to target page properly, so between unlocking the pte and trying to take a new reference to the page with isolate_lru_page, anything could happen to it. Fix this by holding the pte lock until we get a chance to elevate the refcount. Other small cleanups while we're here. Signed-off-by: Nick Piggin Signed-off-by: Christoph Lameter Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/swap.c | 26 ++++++++++++++++++++++++++ 1 file changed, 26 insertions(+) (limited to 'mm/swap.c') diff --git a/mm/swap.c b/mm/swap.c index cbb48e721ab9..bc2442a7b0ee 100644 --- a/mm/swap.c +++ b/mm/swap.c @@ -174,6 +174,32 @@ void lru_add_drain(void) put_cpu(); } +#ifdef CONFIG_NUMA +static void lru_add_drain_per_cpu(void *dummy) +{ + lru_add_drain(); +} + +/* + * Returns 0 for success + */ +int lru_add_drain_all(void) +{ + return schedule_on_each_cpu(lru_add_drain_per_cpu, NULL); +} + +#else + +/* + * Returns 0 for success + */ +int lru_add_drain_all(void) +{ + lru_add_drain(); + return 0; +} +#endif + /* * This path almost never happens for VM activity - pages are normally * freed via pagevecs. But it gets used by networking. -- cgit v1.2.3-55-g7522