From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Steve Wise" Subject: RE: [PATCH rdma-core 0/5] Common systemd/udev based boot support Date: Fri, 28 Jul 2017 08:51:28 -0500 Message-ID: <000d01d307a8$9cc0d660$d6428320$@opengridcomputing.com> References: <1500929067-1583-1-git-send-email-jgunthorpe@obsidianresearch.com> <00e601d30562$f5a7dff0$e0f79fd0$@opengridcomputing.com> <20170725164004.GA20959@obsidianresearch.com> <011601d30576$c3ac38c0$4b04aa40$@opengridcomputing.com> <20170725213354.GE10905@obsidianresearch.com> <016901d30590$3eee9910$bccbcb30$@opengridcomputing.com> <20170725220210.GA15663@obsidianresearch.com> <009901d30618$2d957e30$88c07a90$@opengridcomputing.com> <20170726162419.GC20499@obsidianresearch.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: Content-Language: en-us Sender: linux-rdma-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: 'Jason Gunthorpe' Cc: linux-rdma-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, 'Doug Ledford' , 'Ram Amrani' , 'Ira Weiny' , 'Benjamin Drung' , 'Jarod Wilson' , Chien Tin Tung , mustafa.ismail-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org List-Id: linux-rdma@vger.kernel.org > > On Wed, Jul 26, 2017 at 09:05:03AM -0500, Steve Wise wrote: > > > > > > I think you should change this to create the RDMA device when the > > > > module is installed and the hardware is present.. > > > > > > > > > > Not gonna happen. cxgb4 doesn't setup the queues, rss, irq mappings, etc, until > > > an interface is brought up. So iw_cxgb4 cannot initialize and register with the > > > rdma core until that happens. > > > > But it doesn't tear all that stuff down on ifdown? > > hmm. I need to relook at this. I'm very sure the intent was offload connections do > not get torn down if the link goes down. > Hey Jason, Bringing down the NIC interfaces doesn't totally stop the adapter nor destroy the queues needed for RDMA. It does bring the links down on the ethernet interfaces though. So it behaves like I thought. I tested this by running an rping, and while it was pushing rdma traffic, I did 'ifconfig ethX 0.0.0.0 down' on the interface in use. The data flow stopped (and the iWARP/TCP stack started retransmitting). I then brought the link back up, and after a few seconds the rping traffic continued on. Steve -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html