path: root/mm
diff options
authorKOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>2008-12-09 13:14:16 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2008-12-10 08:01:53 -0800
commit6841c8e26357904ef462650273f5d5015f7bb370 (patch)
tree17621c8b63393b725f42dad26ac671dd1926c9c1 /mm
parent02d211688727ad02bb4555b1aa8ae2de16b21b39 (diff)
mm: remove UP version of lru_add_drain_all()
Currently, lru_add_drain_all() has two version. (1) use schedule_on_each_cpu() (2) don't use schedule_on_each_cpu() Gerald Schaefer reported it doesn't work well on SMP (not NUMA) S390 machine. offline_pages() calls lru_add_drain_all() followed by drain_all_pages(). While drain_all_pages() works on each cpu, lru_add_drain_all() only runs on the current cpu for architectures w/o CONFIG_NUMA. This let us run into the BUG_ON(!PageBuddy(page)) in __offline_isolated_pages() during memory hotplug stress test on s390. The page in question was still on the pcp list, because of a race with lru_add_drain_all() and drain_all_pages() on different cpus. Actually, Almost machine has CONFIG_UNEVICTABLE_LRU=y. Then almost machine use (1) version lru_add_drain_all although the machine is UP. Then this ifdef is not valueable. simple removing is better. Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Christoph Lameter <cl@linux-foundation.org> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com> Acked-by: Gerald Schaefer <gerald.schaefer@de.ibm.com> Cc: Dave Hansen <dave@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm')
1 files changed, 0 insertions, 13 deletions
diff --git a/mm/swap.c b/mm/swap.c
index 2881987603e..b135ec90cde 100644
--- a/mm/swap.c
+++ b/mm/swap.c
@@ -299,7 +299,6 @@ void lru_add_drain(void)
-#if defined(CONFIG_NUMA) || defined(CONFIG_UNEVICTABLE_LRU)
static void lru_add_drain_per_cpu(struct work_struct *dummy)
@@ -313,18 +312,6 @@ int lru_add_drain_all(void)
return schedule_on_each_cpu(lru_add_drain_per_cpu);
- * Returns 0 for success
- */
-int lru_add_drain_all(void)
- lru_add_drain();
- return 0;
* Batched page_cache_release(). Decrement the reference count on all the
* passed pages. If it fell to zero then remove the page from the LRU and