From: Tom Tucker Subject: [PATCH REPOST2] svcrdma: Limit ORD based on client's advertised IRD Date: Mon, 19 May 2008 19:11:35 -0500 Message-ID: <1211242295.31725.95.camel@trinity.ogc.int> Mime-Version: 1.0 Content-Type: text/plain Cc: "Talpey, Thomas" , linux-nfs To: Bruce Fields Return-path: Received: from smtp.opengridcomputing.com ([209.198.142.2]:60886 "EHLO smtp.opengridcomputing.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756277AbYETAIF (ORCPT ); Mon, 19 May 2008 20:08:05 -0400 Sender: linux-nfs-owner@vger.kernel.org List-ID: When adapters have differing IRD limits, the RDMA transport will fail to connect properly. The RDMA transport should use the client's advertised inbound read limit when computing its outbound read limit. For iWARP transports, there is currently no standard for exchanging IRD/ORD during connection establishment so the 'responder_resources' field in the connect event is the local device's limit. The RDMA transport can be configured to use a smaller ORD by writing the desired number to the /proc/sys/sunrpc/svc_rdma/max_outbound_read_requests file. Signed-off-by: Tom Tucker --- This one includes the min_t change. This is nicer. Thanks Tom. net/sunrpc/xprtrdma/svc_rdma_transport.c | 16 ++++++++++++---- 1 files changed, 12 insertions(+), 4 deletions(-) diff --git a/net/sunrpc/xprtrdma/svc_rdma_transport.c b/net/sunrpc/xprtrdma/svc_rdma_transport.c index 68908b5..54b2126 100644 --- a/net/sunrpc/xprtrdma/svc_rdma_transport.c +++ b/net/sunrpc/xprtrdma/svc_rdma_transport.c @@ -580,7 +580,7 @@ int svc_rdma_post_recv(struct svcxprt_rdma *xprt) * will call the recvfrom method on the listen xprt which will accept the new * connection. */ -static void handle_connect_req(struct rdma_cm_id *new_cma_id) +static void handle_connect_req(struct rdma_cm_id *new_cma_id, size_t client_ird) { struct svcxprt_rdma *listen_xprt = new_cma_id->context; struct svcxprt_rdma *newxprt; @@ -597,6 +597,9 @@ static void handle_connect_req(struct rdma_cm_id *new_cma_id) dprintk("svcrdma: Creating newxprt=%p, cm_id=%p, listenxprt=%p\n", newxprt, newxprt->sc_cm_id, listen_xprt); + /* Save client advertised inbound read limit for use later in accept. */ + newxprt->sc_ord = client_ird; + /* Set the local and remote addresses in the transport */ sa = (struct sockaddr *)&newxprt->sc_cm_id->route.addr.dst_addr; svc_xprt_set_remote(&newxprt->sc_xprt, sa, svc_addr_len(sa)); @@ -633,7 +636,8 @@ static int rdma_listen_handler(struct rdma_cm_id *cma_id, case RDMA_CM_EVENT_CONNECT_REQUEST: dprintk("svcrdma: Connect request on cma_id=%p, xprt = %p, " "event=%d\n", cma_id, cma_id->context, event->event); - handle_connect_req(cma_id); + handle_connect_req(cma_id, + event->param.conn.responder_resources); break; case RDMA_CM_EVENT_ESTABLISHED: @@ -807,8 +811,12 @@ static struct svc_xprt *svc_rdma_accept(struct svc_xprt *xprt) (size_t)svcrdma_max_requests); newxprt->sc_sq_depth = RPCRDMA_SQ_DEPTH_MULT * newxprt->sc_max_requests; - newxprt->sc_ord = min((size_t)devattr.max_qp_rd_atom, - (size_t)svcrdma_ord); + /* + * Limit ORD based on client limit, local device limit, and + * configured svcrdma limit. + */ + newxprt->sc_ord = min_t(size_t, devattr.max_qp_rd_atom, newxprt->sc_ord); + newxprt->sc_ord = min_t(size_t, svcrdma_ord, newxprt->sc_ord); newxprt->sc_pd = ib_alloc_pd(newxprt->sc_cm_id->device); if (IS_ERR(newxprt->sc_pd)) {