[patch] mm/memcontrol.c::mem_cgroup_migrate() - replace another local_irq_disable() w. local_lock_irq()

[Mike Galbraith]

v4.6 grew a local_irq_disable() in mm/memcontrol.c::mem_cgroup_migrate().
Convert it to use the existing local lock (event_lock) like the others.

Signed-off-by: Mike Galbraith <umgwanakikbuti@xxxxxxxxx>
---
 mm/memcontrol.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -5557,10 +5557,10 @@ void mem_cgroup_migrate(struct page *old
 
 	commit_charge(newpage, memcg, false);
 
-	local_irq_disable();
+	local_lock_irq(event_lock);
 	mem_cgroup_charge_statistics(memcg, newpage, compound, nr_pages);
 	memcg_check_events(memcg, newpage);
-	local_irq_enable();
+	local_unlock_irq(event_lock);
 }
 
 DEFINE_STATIC_KEY_FALSE(memcg_sockets_enabled_key);