mm: drain percpu lru add/rotate page-vectors on cpu hot-unplug
This cpu hotplug hook was accidentally removed in commit 00a62ce91e55
("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 <[email protected]>
Cc: Dave Hansen <[email protected]>
Cc: KOSAKI Motohiro <[email protected]>
Cc: Eric B Munson <[email protected]>
Cc: Mel Gorman <[email protected]>
Cc: Christoph Lameter <[email protected]>
Cc: KAMEZAWA Hiroyuki <[email protected]>
Cc: Johannes Weiner <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 98552cf..673596a 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -4825,6 +4825,7 @@
int cpu = (unsigned long)hcpu;
if (action == CPU_DEAD || action == CPU_DEAD_FROZEN) {
+ lru_add_drain_cpu(cpu);
drain_pages(cpu);
/*
