From: Matt Fleming <matt@xxxxxxxxxxxxxxxxxxx> v4.14.172-rt78-rc1 stable review patch. If anyone has any objections, please let me know. ----------- [ Upstream commit 071a1d6a6e14d0dec240a8c67b425140d7f92f6a ] The comment about local_lock_irqsave() mentions just the counters and css_put_many()'s callback just invokes a worker so it is safe to move the unlock function after memcg_check_events() so css_put_many() can be invoked without the lock acquired. Cc: Daniel Wagner <wagi@xxxxxxxxx> Signed-off-by: Matt Fleming <matt@xxxxxxxxxxxxxxxxxxx> [bigeasy: rewrote the patch description] Signed-off-by: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx> Signed-off-by: Tom Zanussi <zanussi@xxxxxxxxxx> --- mm/memcontrol.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 0503b31e2a873..a359a24ebd9f0 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -6102,10 +6102,10 @@ void mem_cgroup_swapout(struct page *page, swp_entry_t entry) mem_cgroup_charge_statistics(memcg, page, PageTransHuge(page), -nr_entries); memcg_check_events(memcg, page); + local_unlock_irqrestore(event_lock, flags); if (!mem_cgroup_is_root(memcg)) css_put_many(&memcg->css, nr_entries); - local_unlock_irqrestore(event_lock, flags); } /** -- 2.14.1
