Re: [PATCH] svcrdma: remove rdma_create_qp() failure recovery logic

J. Bruce Fields
2014-08-05T19:10:18Z

Thanks, applying for 3.17.--b.

On Thu, Jul 31, 2014 at 03:26:07PM -0500, Steve Wise wrote:
> In svc_rdma_accept(), if rdma_create_qp() fails, there is useless
> logic to try and call rdma_create_qp() again with reduced sge depths.
> The assumption, I guess, was that perhaps the initial sge depths
> chosen were too big. However they initial depths are selected based
> on the rdma device attribute max_sge returned from ib_query_device().
> If rdma_create_qp() fails, it would not be because the max_send_sge and
> max_recv_sge values passed in exceed the device's max. So just remove
> this code.
>
> Signed-off-by: Steve Wise <swise-7bPotxP6k4+P2YhJcF5u+vpXobYPEAuW@public.gmane.org>
> ---
>
> net/sunrpc/xprtrdma/svc_rdma_transport.c | 19 ++-----------------
> 1 files changed, 2 insertions(+), 17 deletions(-)
>
> diff --git a/net/sunrpc/xprtrdma/svc_rdma_transport.c b/net/sunrpc/xprtrdma/svc_rdma_transport.c
> index e7323fb..282a43b 100644
> --- a/net/sunrpc/xprtrdma/svc_rdma_transport.c
> +++ b/net/sunrpc/xprtrdma/svc_rdma_transport.c
> @@ -942,23 +942,8 @@ static struct svc_xprt *svc_rdma_accept(struct svc_xprt *xprt)
>
> ret = rdma_create_qp(newxprt->sc_cm_id, newxprt->sc_pd, &qp_attr);
> if (ret) {
> - /*
> - * XXX: This is a hack. We need a xx_request_qp interface
> - * that will adjust the qp_attr's with a best-effort
> - * number
> - */
> - qp_attr.cap.max_send_sge -= 2;
> - qp_attr.cap.max_recv_sge -= 2;
> - ret = rdma_create_qp(newxprt->sc_cm_id, newxprt->sc_pd,
> - &qp_attr);
> - if (ret) {
> - dprintk("svcrdma: failed to create QP, ret=%d\n", ret);
> - goto errout;
> - }
> - newxprt->sc_max_sge = qp_attr.cap.max_send_sge;
> - newxprt->sc_max_sge = qp_attr.cap.max_recv_sge;
> - newxprt->sc_sq_depth = qp_attr.cap.max_send_wr;
> - newxprt->sc_max_requests = qp_attr.cap.max_recv_wr;
> + dprintk("svcrdma: failed to create QP, ret=%d\n", ret);
> + goto errout;
> }
> newxprt->sc_qp = newxprt->sc_cm_id->qp;
>
>