From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <linux-kernel-owner@vger.kernel.org>
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
	id S1753443AbcAGUlP (ORCPT <rfc822;w@1wt.eu>);
	Thu, 7 Jan 2016 15:41:15 -0500
Received: from mail-yk0-f170.google.com ([209.85.160.170]:36269 "EHLO
	mail-yk0-f170.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org
	with ESMTP id S1752492AbcAGUlM (ORCPT
	<rfc822;linux-kernel@vger.kernel.org>);
	Thu, 7 Jan 2016 15:41:12 -0500
Date: Thu, 7 Jan 2016 15:41:10 -0500
From: Tejun Heo <tj@kernel.org>
To: Parav Pandit <pandit.parav@gmail.com>
Cc: cgroups@vger.kernel.org, linux-doc@vger.kernel.org,
        linux-kernel@vger.kernel.org, linux-rdma@vger.kernel.org,
        lizefan@huawei.com, Johannes Weiner <hannes@cmpxchg.org>,
        Doug Ledford <dledford@redhat.com>, Liran Liss <liranl@mellanox.com>,
        "Hefty, Sean" <sean.hefty@intel.com>,
        Jason Gunthorpe <jgunthorpe@obsidianresearch.com>,
        Haggai Eran <haggaie@mellanox.com>, Jonathan Corbet <corbet@lwn.net>,
        james.l.morris@oracle.com, serge@hallyn.com,
        Or Gerlitz <ogerlitz@mellanox.com>, Matan Barak <matanb@mellanox.com>,
        raindel@mellanox.com, akpm@linux-foundation.org,
        linux-security-module@vger.kernel.org
Subject: Re: [PATCHv1 3/6] rdmacg: implements rdma cgroup
Message-ID: <20160107204110.GH1898@mtj.duckdns.org>
References: <1452020286-9508-1-git-send-email-pandit.parav@gmail.com>
 <1452020286-9508-4-git-send-email-pandit.parav@gmail.com>
 <20160105220128.GJ5995@mtj.duckdns.org>
 <CAG53R5UjsDa+JK_afrQ5pMpiDPrc+a+yCOOH3X105pTmU_a53A@mail.gmail.com>
 <20160107152936.GE29797@mtj.duckdns.org>
 <CAG53R5Vg9jULp9EU23yd+iUqMDyTMNmUycD8ygX_j98O=JUDmA@mail.gmail.com>
 <20160107202818.GF1898@mtj.duckdns.org>
 <CAG53R5UuCNwCKWAuub=n3FkJR6Z5oyF6cVPeW=5nk-JrURY=jw@mail.gmail.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <CAG53R5UuCNwCKWAuub=n3FkJR6Z5oyF6cVPeW=5nk-JrURY=jw@mail.gmail.com>
User-Agent: Mutt/1.5.24 (2015-08-30)
Sender: linux-kernel-owner@vger.kernel.org
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.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