Hello, Michal. On Tue, Jan 17, 2017 at 02:58:30PM +0100, Michal Hocko wrote: > This would require using hierarchical cgroup iterators to iterate over It does behave hierarchically. > tasks. As per Andy's testing this doesn't seem to be the case. I haven't That's not what Andy's testing showed. What that showed was that program in a child can override the one from its ancestor. > checked the implementation closely but my understanding was that using > only cgroup specific tasks was intentional. Maybe I'm misreading you but if you're saying that a bpf program would only execute for tasks on that specific cgroup, that is not true. > I do agree that using hierarchy aware cgroup iterators is the right > approach here and we wouldn't see any issue. But I am still not sure > I've wrapped my head around this feature completely. It's really simple. You can install bpf programs with a cgroup path associated with them. When that particular type of bpf program needs to be executed, the bpf program which is attached to the closest ancestor (including self) is executed. Thanks. -- tejun -- To unsubscribe from this list: send the line "unsubscribe linux-api" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
