On 09/15/2012 12:39 AM, Tejun Heo wrote: > Hello, again. > > On Fri, Sep 14, 2012 at 12:49:50PM -0700, Tejun Heo wrote: >> That said, if someone can think of a better solution, I'm all ears. >> One thing that *has* to be maintained is that it should be able to tag >> a resource in such way that its associated controllers are >> identifiable regardless of which task is looking at it. > > So, I thought about it more. How about we do "consider / ignore this > node" instead of "(don't) nest beyond this level". For example, let's > assume a tree like the following. > > R > / | \ > A B C > / \ > AA AB > > If we want to differentiate between AA and AB, we'll have to consider > the whole tree with the previous sheme - A needs to nest, so R needs > to nest and we end up with the whole tree. Instead, if we have honor > / ignore this node. We can set the honor bit on A, AA and AB and see > the tree as > > R > / > A > / \ > AA AB > > We still see the intermediate A node but can ignore the other > branches. Implementation and concept-wise, it's fairly simple too. > For any given node and controller, you travel upwards until you meet a > node which has the controller enabled and that's the cgroup the > controller considers. > > Thanks. > That is exactly what I proposed in our previous discussions around memcg, with files like "available_controllers" , "current_controllers". Name chosen to match what other subsystems already do. if memcg is not in "available_controllers" for a node, it cannot be seen by anyone bellow that level. -- 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
