We are using nocpu_base to accumulate charges on the main counters during cpu hotplug. I have a similar need, which is transferring charges to the root cgroup when lazily enabling memcg. Because system wide information is not kept per-cpu, it is hard to distribute it. This field works well for this. So we need to make it available for all usages, not only hotplug cases. Signed-off-by: Glauber Costa <glommer@xxxxxxxxxxxxx> Cc: Michal Hocko <mhocko@xxxxxxx> Cc: Kamezawa Hiroyuki <kamezawa.hiroyu@xxxxxxxxxxxxxx> Cc: Johannes Weiner <hannes@xxxxxxxxxxx> Cc: Tejun Heo <tj@xxxxxxxxxx> --- mm/memcontrol.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 669d16a..b8b363f 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -921,11 +921,11 @@ static long mem_cgroup_read_stat(struct mem_cgroup *memcg, get_online_cpus(); for_each_online_cpu(cpu) val += per_cpu(memcg->stat->count[idx], cpu); -#ifdef CONFIG_HOTPLUG_CPU + spin_lock(&memcg->pcp_counter_lock); val += memcg->nocpu_base.count[idx]; spin_unlock(&memcg->pcp_counter_lock); -#endif + put_online_cpus(); return val; } @@ -945,11 +945,11 @@ static unsigned long mem_cgroup_read_events(struct mem_cgroup *memcg, for_each_online_cpu(cpu) val += per_cpu(memcg->stat->events[idx], cpu); -#ifdef CONFIG_HOTPLUG_CPU + spin_lock(&memcg->pcp_counter_lock); val += memcg->nocpu_base.events[idx]; spin_unlock(&memcg->pcp_counter_lock); -#endif + return val; } -- 1.8.1.2 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>