On 2019/7/11 下午9:47, Peter Zijlstra wrote:
[snip]
>> + rcu_read_lock();
>> + memcg = mem_cgroup_from_task(p);
>> + if (idx != -1)
>> + this_cpu_inc(memcg->stat_numa->locality[idx]);
>
> I thought cgroups were supposed to be hierarchical. That is, if we have:
>
> R
> / \
> A
> /\
> B
> \
> t1
>
> Then our task t1 should be accounted to B (as you do), but also to A and
> R.
I get the point but not quite sure about this...
Not like pages there are no hierarchical limitation on locality, also tasks
running in a particular group have no influence to others, not to mention the
extra overhead, does it really meaningful to account the stuff hierarchically?
Regards,
Michael Wang
>
>> + rcu_read_unlock();
>> +}
>> +#endif