From mboxrd@z Thu Jan 1 00:00:00 1970 From: Leon Romanovsky Subject: Re: [EXT] Re: [PATCH net-next 07/10] qed*: Add iWARP 100g support Date: Thu, 2 May 2019 15:31:18 +0300 Message-ID: <20190502123118.GR7676@mtr-leonro.mtl.com> References: <20190501095722.6902-1-michal.kalderon@marvell.com> <20190501095722.6902-8-michal.kalderon@marvell.com> <20190501.203522.1577716429222042609.davem@davemloft.net> <20190502051320.GF7676@mtr-leonro.mtl.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: Sender: netdev-owner@vger.kernel.org To: Michal Kalderon Cc: David Miller , Ariel Elior , "jgg@ziepe.ca" , "dledford@redhat.com" , "linux-rdma@vger.kernel.org" , "netdev@vger.kernel.org" , "linux-scsi@vger.kernel.org" List-Id: linux-rdma@vger.kernel.org On Thu, May 02, 2019 at 12:10:39PM +0000, Michal Kalderon wrote: > > From: Leon Romanovsky > > Sent: Thursday, May 2, 2019 8:13 AM > > On Wed, May 01, 2019 at 08:35:22PM -0400, David Miller wrote: > > > From: Michal Kalderon > > > Date: Wed, 1 May 2019 12:57:19 +0300 > > > > > > > diff --git a/drivers/infiniband/hw/qedr/main.c > > > > b/drivers/infiniband/hw/qedr/main.c > > > > index d93c8a893a89..8bc6775abb79 100644 > > > > --- a/drivers/infiniband/hw/qedr/main.c > > > > +++ b/drivers/infiniband/hw/qedr/main.c > > > > @@ -52,6 +52,10 @@ MODULE_DESCRIPTION("QLogic 40G/100G ROCE > > > > Driver"); MODULE_AUTHOR("QLogic Corporation"); > > > > MODULE_LICENSE("Dual BSD/GPL"); > > > > > > > > +static uint iwarp_cmt; > > > > +module_param(iwarp_cmt, uint, 0444); > > MODULE_PARM_DESC(iwarp_cmt, " > > > > +iWARP: Support CMT mode. 0 - Disabled, 1 - Enabled. Default: > > > > +Disabled"); > > > > + > > > > > > Sorry no, this is totally beneath us. > > > > It is not acceptable for RDMA too. > > Dave and Leon, > > This is a bit of a special case related specifically to our hardware. > Enabling iWARP on this kind of configuration impacts L2 performance. > We don't want this to happen implicitly once the rdma driver is loaded since > that can happen automatically and could lead to unexpected behavior from user perspective. > Therefore we need a way of giving the user control to decide whether they want iWARP at the cost > of L2 performance degradation. > We also need this information as soon as the iWARP device registers, so using the rdma-tool would be too late. > > If module parameter is not an option, could you please advise what would be ok ? > ethtool private flags ? > devlink ? Yes, devlink params are modern way to have same functionality as module parameters. This patch can help you in order to get a sense of how to do it. https://lore.kernel.org/patchwork/patch/959195/ Thanks > > thanks, > Michal > > > > > Also please don't use comments inside function calls, it complicates various > > checkers without real need. > > dev->ops->iwarp_set_engine_affin(dev->cdev, true /* reset */); > > ^^^^^^^^^^^^^^ Thanks