From mboxrd@z Thu Jan  1 00:00:00 1970
From: Tejun Heo <tj-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
Subject: Re: [PATCHv1 3/6] rdmacg: implements rdma cgroup
Date: Thu, 7 Jan 2016 15:41:10 -0500
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To: Parav Pandit <pandit.parav-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
Cc: cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-doc-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-rdma-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, lizefan-hv44wF8Li93QT0dZR+AlfA@public.gmane.org, Johannes Weiner <hannes-druUgvl0LCNAfugRpC6u6w@public.gmane.org>, Doug Ledford <dledford-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>, Liran Liss <liranl-VPRAkNaXOzVWk0Htik3J/w@public.gmane.org>, "Hefty, Sean" <sean.hefty-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>, Jason Gunthorpe <jgunthorpe-ePGOBjL8dl3ta4EC/59zMFaTQe2KTcn/@public.gmane.org>, Haggai Eran <haggaie-VPRAkNaXOzVWk0Htik3J/w@public.gmane.org>, Jonathan Corbet <corbet-T1hC0tSOHrs@public.gmane.org>, james.l.morris-QHcLZuEGTsvQT0dZR+AlfA@public.gmane.org, serge-A9i7LUbDfNHQT0dZR+AlfA@public.gmane.org, Or Gerlitz <ogerlitz-VPRAkNaXOzVWk0Htik3J/w@public.gmane.org>, Matan Barak <matanb-VPRAkNaXOzVWk0Htik3J/w@public.gmane.org>, raindel-VPRAkNaXOzVWk0Htik3J/w@public.gmane.org, akpm-de/tnXTf+JLsfHDXvbKv3WD2FQJk+8+b@public.gmane.org, linux-security-module-u79uwXL29TY76Z2rM5mHXA@public.gmane.org

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