On Fri, Jan 8, 2016 at 1:58 AM, Tejun Heo <tj@xxxxxxxxxx> wrote: > Hello, Parav. > > On Fri, Jan 08, 2016 at 01:55:09AM +0530, Parav Pandit wrote: > ... >> Above functionality is achieved, by maintaining the map this tgid and >> associated original cgroup at try_charge(), uncharge() time. > > Hmmm, what happens after the following? > > 1. A process allocates some rdma resources and get registered on the > hash table. > > 2. The process gets migrated to a different cgroup. > > 3. The process allocates more rdma resources. > > Which cgroup would the resources from #3 be attributed to? Since the pid/tgid of the process doesn't change in step_3, it allocates from original cgroup of step_1. However in next patch V2, as described below, since IB resource will store rdma_cg pointer, in step_3, new resource will be allocated from new cgroup. old resource will be freed from older cgroup. This is what you are expecting, right? > >> In alternate method, >> Its simple to store the pointer of rdma_cgroup structure in the IB >> resource structure and hold on reference count to rdma_cgroup. >> so that when its freed, uncharge_resource can accept rdma_cgroup >> structure pointer. > > That'd be a lot more in line with how other controllers behave. > > Thanks. > > -- > tejun -- To unsubscribe from this list: send the line "unsubscribe linux-doc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
