From mboxrd@z Thu Jan 1 00:00:00 1970 From: Knut Omang Subject: Re: [PATCH libibverbs v2 3/3] Provide remote XRC SRQ number in kernel post_send. Date: Tue, 20 Sep 2016 15:38:46 +0200 Message-ID: <1474378726.20134.140.camel@oracle.com> References: <20160919052911.GF3273@leon.nu> <1474276356.24045.93.camel@oracle.com> <20160920101839.GF26673@leon.nu> <1474368210.8837.3.camel@oracle.com> <20160920110115.GJ26673@leon.nu> <1474369715.8837.19.camel@oracle.com> <20160920121741.GL26673@leon.nu> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20160920121741.GL26673-2ukJVAZIZ/Y@public.gmane.org> Sender: linux-rdma-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Leon Romanovsky Cc: Doug Ledford , linux-rdma-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Mukesh Kacker List-Id: linux-rdma@vger.kernel.org On Tue, 2016-09-20 at 15:17 +0300, Leon Romanovsky wrote: > On Tue, Sep 20, 2016 at 01:08:35PM +0200, Knut Omang wrote: > > On Tue, 2016-09-20 at 14:01 +0300, Leon Romanovsky wrote: > > > On Tue, Sep 20, 2016 at 12:43:30PM +0200, Knut Omang wrote: > > > > > > > > On Tue, 2016-09-20 at 13:18 +0300, Leon Romanovsky wrote: > > > > > > > > > > On Mon, Sep 19, 2016 at 11:12:36AM +0200, Knut Omang wrote: > > > > > > > > > > > > > > > > > > On Mon, 2016-09-19 at 08:29 +0300, Leon Romanovsky wrote: > > > > > > > > > > > > > > > > > > > > > On Sat, Sep 17, 2016 at 05:59:13AM +0200, Knut Omang wrote: > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > Also proper end align the ibv_kern_send_wr struct. > > > > > > > > > > > > > > > > Requires a corresponding kernel change. > > > > > > > > > > > > > > > > Signed-off-by: Knut Omang > > > > > > > > Reviewed-by: Mukesh Kacker > > > > > > > > --- > > > > > > > > include/infiniband/kern-abi.h | 1 + > > > > > > > > src/cmd.c | 2 ++ > > > > > > > > 2 files changed, 3 insertions(+), 0 deletions(-) > > > > > > > > > > > > > > > > diff --git a/include/infiniband/kern-abi.h b/include/infiniband/kern-abi.h > > > > > > > > index 8bdeef5..7b1d310 100644 > > > > > > > > --- a/include/infiniband/kern-abi.h > > > > > > > > +++ b/include/infiniband/kern-abi.h > > > > > > > > @@ -800,6 +800,7 @@ struct ibv_kern_send_wr { > > > > > > > > union { > > > > > > > > struct { > > > > > > > > __u32 remote_srqn; > > > > > > > > + __u32 reserved; > > > > > > > > } xrc; > > > > > > > > } qp_type; > > > > > > > > }; > > > > > > > > diff --git a/src/cmd.c b/src/cmd.c > > > > > > > > index a418ee1..a4e2f75 100644 > > > > > > > > --- a/src/cmd.c > > > > > > > > +++ b/src/cmd.c > > > > > > > > @@ -1293,6 +1293,8 @@ int ibv_cmd_post_send(struct ibv_qp *ibqp, struct ibv_send_wr *wr, > > > > > > > > tmp->wr.ud.remote_qpn = i->wr.ud.remote_qpn; > > > > > > > > tmp->wr.ud.remote_qkey = i->wr.ud.remote_qkey; > > > > > > > > } else { > > > > > > > > + if (ibqp->qp_type == IBV_QPT_XRC_SEND) > > > > > > > > + tmp->qp_type.xrc.remote_srqn = i->qp_type.xrc.remote_srqn; > > > > > > > It will be checked for all QPTs and for all consumers. Any chances to > > > > > > > optimize it? > > > > > > All QPTs except UD, yes. > > > > > > > > > > > > The easiest is perhaps just to remove the test (and set the attribute in all cases), which will work fine > > > > > > as long as the qp_type union is not used for anything else, but is it worth > > > > > > the loss of intuitiveness/future potential correctness of the code? > > > > > Let's concentrate on the present and as far as I see there are no kernel users who > > > > > need this field xrc.remote_srqn field. > > > > So I assume then that you are ok with this code, given my explanation? > > > Partially, > > > > > > I'm fine with the claim about readability and the fact that > > > this code is not in data-path relaxed me a little bit. > > > > Good! > > > > > I'm not fine with the part that this code doesn't do anything in kernel. > > > > I know, I have two big patch sets one kernel and one for the new "rdma consolidated" > > in the queue that should fix that, just want to save a few versions of those > > ~32000 lines of code by preparing the baseline :-) > > It won't save. We DO believe you that this this new addition to UAPI is really > needed, but we NEED to see that it is unavoidable. > > The proper flow for submission is driver->kernel_core->libraries and not > kernel_core->libraries->driver. Ok, got it.. Knut > Thanks -- 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