On Mon, 2015-05-04 at 17:11 +0800, Zefan Li wrote: > >>> Some degree of flexibility is provided so that you may disable some controllers > >>> in a subtree. For example: > >>> > >>> root ---> child1 > >>> (cpuset,memory,cpu) (cpuset,memory) > >>> \ > >>> \-> child2 > >>> (cpu) > >> > >> Whew, that's a relief. Thanks. > > > > But somehow I'm not feeling a whole lot better. > > > > "May" means if you don't explicitly take some action to disable group > > scheduling, you get it (I don't care if I have an off button), but that > > would also seemingly mean that we would then have rt tasks in taskgroups > > with no bandwidth allocated, ie you have to make group scheduling for rt > > tasks meaningless until a bandwidth appeared, and to make bandwidth > > appear, you'd have to stop the world, distribute, continue, no? > > > > The current "just say no" seems a lot more sensible. > > > > I just realized we allow removing/adding controllers from/to cgroups > while there are tasks in them, which isn't safe unless we eliminate all > can_attach callbacks. We've done so for some cgroup subsystems, but > there are still a few of them... I was pondering the future (or so I thought), but seems it turned into the past while I wasn't looking. Oh well, you found a bug anyway. -Mike -- To unsubscribe from this list: send the line "unsubscribe cgroups" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
