diff options
Diffstat (limited to 'mm')
| -rw-r--r-- | mm/memcontrol.c | 9 |
1 files changed, 9 insertions, 0 deletions
diff --git a/mm/memcontrol.c b/mm/memcontrol.c index c265212bec8c..66beca1ad92f 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -2559,6 +2559,15 @@ unsigned long mem_cgroup_soft_limit_reclaim(pg_data_t *pgdat, int order, return 0; mctz = soft_limit_tree_node(pgdat->node_id); + + /* + * Do not even bother to check the largest node if the root + * is empty. Do it lockless to prevent lock bouncing. Races + * are acceptable as soft limit is best effort anyway. + */ + if (RB_EMPTY_ROOT(&mctz->rb_root)) + return 0; + /* * This loop can run a while, specially if mem_cgroup's continuously * keep exceeding their soft limit and putting the system under |