Re: [PATCHv1 3/6] rdmacg: implements rdma cgroup

From: Tejun Heo
Date: Thu Jan 07 2016 - 15:41:19 EST


Hello, Parav.

On Fri, Jan 08, 2016 at 02:09:23AM +0530, Parav Pandit wrote:
> > 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.

It shouldn't work that way.

> 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?

Yeap.

Thanks.

--
tejun