mm: drain percpu lru add/rotate page-vectors on cpu hot-unplug

This cpu hotplug hook was accidentally removed in commit 00a62ce91e
("mm: fix Committed_AS underflow on large NR_CPUS environment")

The visible effect of this accident: some pages are borrowed in per-cpu
page-vectors.  Truncate can deal with it, but these pages cannot be
reused while this cpu is offline.  So this is like a temporary memory
leak.

Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org>
Cc: Dave Hansen <dave@linux.vnet.ibm.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Eric B Munson <ebmunson@us.ibm.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Konstantin Khlebnikov 2012-03-21 16:34:06 -07:00 committed by Linus Torvalds
parent 3268c63ede
commit f0cb3c76ae
3 changed files with 4 additions and 2 deletions

View File

@ -223,6 +223,7 @@ extern void lru_add_page_tail(struct zone* zone,
extern void activate_page(struct page *);
extern void mark_page_accessed(struct page *);
extern void lru_add_drain(void);
extern void lru_add_drain_cpu(int cpu);
extern int lru_add_drain_all(void);
extern void rotate_reclaimable_page(struct page *page);
extern void deactivate_page(struct page *page);

View File

@ -4825,6 +4825,7 @@ static int page_alloc_cpu_notify(struct notifier_block *self,
int cpu = (unsigned long)hcpu;
if (action == CPU_DEAD || action == CPU_DEAD_FROZEN) {
lru_add_drain_cpu(cpu);
drain_pages(cpu);
/*

View File

@ -496,7 +496,7 @@ static void lru_deactivate_fn(struct page *page, void *arg)
* Either "cpu" is the current CPU, and preemption has already been
* disabled; or "cpu" is being hot-unplugged, and is already dead.
*/
static void drain_cpu_pagevecs(int cpu)
void lru_add_drain_cpu(int cpu)
{
struct pagevec *pvecs = per_cpu(lru_add_pvecs, cpu);
struct pagevec *pvec;
@ -553,7 +553,7 @@ void deactivate_page(struct page *page)
void lru_add_drain(void)
{
drain_cpu_pagevecs(get_cpu());
lru_add_drain_cpu(get_cpu());
put_cpu();
}