Vladimir notes:
> > + local_irq_disable();
> > + mem_cgroup_charge_statistics(memcg, page, -1);
> > + memcg_check_events(memcg, page);
> > + local_irq_enable();
>
> AFAICT mem_cgroup_swapout() is called under mapping->tree_lock with irqs
> disabled, so we should use irq_save/restore here.
Simply remove the irq-disabling altogether and rely on the caller
holding the mapping->tree_lock for now.
Reported-by: Vladimir Davydov <[email protected]>
Signed-off-by: Johannes Weiner <[email protected]>
Acked-by: Vladimir Davydov <[email protected]>
---
mm/memcontrol.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
For "mm: memcontrol: uncharge pages on swapout" in -mm.
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index ae9b630e928b..09fece0eb9f1 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -5777,10 +5777,11 @@ void mem_cgroup_swapout(struct page *page, swp_entry_t entry)
if (!mem_cgroup_is_root(memcg))
page_counter_uncharge(&memcg->memory, 1);
- local_irq_disable();
+ /* XXX: caller holds IRQ-safe mapping->tree_lock */
+ VM_BUG_ON(!irqs_disabled());
+
mem_cgroup_charge_statistics(memcg, page, -1);
memcg_check_events(memcg, page);
- local_irq_enable();
}
/**
--
2.1.2