This extra irq disable/enable and BUG_ON checking costs 5% readtwice performance on a 2 socket * 26 cores * HT box. So put it into CONFIG_PROVE_LOCKING. Signed-off-by: Alex Shi <alex.shi@xxxxxxxxxxxxxxxxx> Cc: Johannes Weiner <hannes@xxxxxxxxxxx> Cc: Michal Hocko <mhocko@xxxxxxxxxx> Cc: Vladimir Davydov <vdavydov.dev@xxxxxxxxx> Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> Cc: cgroups@xxxxxxxxxxxxxxx Cc: linux-mm@xxxxxxxxx Cc: linux-kernel@xxxxxxxxxxxxxxx --- mm/memcontrol.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 2d71e53ead88..8d7f6336f15c 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -2026,6 +2026,12 @@ struct mem_cgroup *lock_page_memcg(struct page *page) if (unlikely(!memcg)) return NULL; +#ifdef CONFIG_PROVE_LOCKING + local_irq_save(flags); + might_lock(&memcg->move_lock); + local_irq_restore(flags); +#endif + if (atomic_read(&memcg->moving_account) <= 0) return memcg; -- 1.8.3.1
