Return-Path: Received: from mail-io0-f180.google.com ([209.85.223.180]:34660 "EHLO mail-io0-f180.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932839AbbLGUmu (ORCPT ); Mon, 7 Dec 2015 15:42:50 -0500 Subject: [PATCH v3 3/6] svcrdma: Define maximum number of backchannel requests From: Chuck Lever To: linux-rdma@vger.kernel.org, linux-nfs@vger.kernel.org Date: Mon, 07 Dec 2015 15:42:48 -0500 Message-ID: <20151207204248.12988.97122.stgit@klimt.1015granger.net> In-Reply-To: <20151207203851.12988.97804.stgit@klimt.1015granger.net> References: <20151207203851.12988.97804.stgit@klimt.1015granger.net> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Sender: linux-nfs-owner@vger.kernel.org List-ID: Extra resources for handling backchannel requests have to be pre-allocated when a transport instance is created. Set a limit. Signed-off-by: Chuck Lever --- include/linux/sunrpc/svc_rdma.h | 2 ++ net/sunrpc/xprtrdma/svc_rdma_transport.c | 14 +++++++++----- 2 files changed, 11 insertions(+), 5 deletions(-) diff --git a/include/linux/sunrpc/svc_rdma.h b/include/linux/sunrpc/svc_rdma.h index 2bb0ff3..f71c625 100644 --- a/include/linux/sunrpc/svc_rdma.h +++ b/include/linux/sunrpc/svc_rdma.h @@ -138,6 +138,7 @@ struct svcxprt_rdma { int sc_max_requests; /* Depth of RQ */ int sc_max_req_size; /* Size of each RQ WR buf */ + int sc_max_bc_requests; struct ib_pd *sc_pd; @@ -182,6 +183,7 @@ struct svcxprt_rdma { #define RPCRDMA_SQ_DEPTH_MULT 8 #define RPCRDMA_MAX_REQUESTS 32 #define RPCRDMA_MAX_REQ_SIZE 4096 +#define RPCRDMA_MAX_BC_REQUESTS 2 #define RPCSVC_MAXPAYLOAD_RDMA RPCSVC_MAXPAYLOAD diff --git a/net/sunrpc/xprtrdma/svc_rdma_transport.c b/net/sunrpc/xprtrdma/svc_rdma_transport.c index ede88f3..ed5dd93 100644 --- a/net/sunrpc/xprtrdma/svc_rdma_transport.c +++ b/net/sunrpc/xprtrdma/svc_rdma_transport.c @@ -566,6 +566,7 @@ static struct svcxprt_rdma *rdma_create_xprt(struct svc_serv *serv, cma_xprt->sc_max_req_size = svcrdma_max_req_size; cma_xprt->sc_max_requests = svcrdma_max_requests; + cma_xprt->sc_max_bc_requests = RPCRDMA_MAX_BC_REQUESTS; cma_xprt->sc_sq_depth = svcrdma_max_requests * RPCRDMA_SQ_DEPTH_MULT; atomic_set(&cma_xprt->sc_sq_count, 0); atomic_set(&cma_xprt->sc_ctxt_used, 0); @@ -922,6 +923,7 @@ static struct svc_xprt *svc_rdma_accept(struct svc_xprt *xprt) struct ib_device_attr devattr; int uninitialized_var(dma_mr_acc); int need_dma_mr = 0; + int total_reqs; int ret; int i; @@ -957,8 +959,10 @@ static struct svc_xprt *svc_rdma_accept(struct svc_xprt *xprt) newxprt->sc_max_sge_rd = min_t(size_t, devattr.max_sge_rd, RPCSVC_MAXPAGES); newxprt->sc_max_requests = min((size_t)devattr.max_qp_wr, - (size_t)svcrdma_max_requests); - newxprt->sc_sq_depth = RPCRDMA_SQ_DEPTH_MULT * newxprt->sc_max_requests; + (size_t)svcrdma_max_requests); + newxprt->sc_max_bc_requests = RPCRDMA_MAX_BC_REQUESTS; + total_reqs = newxprt->sc_max_requests + newxprt->sc_max_bc_requests; + newxprt->sc_sq_depth = total_reqs * RPCRDMA_SQ_DEPTH_MULT; for (i = newxprt->sc_sq_depth; i; i--) { struct svc_rdma_op_ctxt *ctxt; @@ -997,7 +1001,7 @@ static struct svc_xprt *svc_rdma_accept(struct svc_xprt *xprt) dprintk("svcrdma: error creating SQ CQ for connect request\n"); goto errout; } - cq_attr.cqe = newxprt->sc_max_requests; + cq_attr.cqe = total_reqs; newxprt->sc_rq_cq = ib_create_cq(newxprt->sc_cm_id->device, rq_comp_handler, cq_event_handler, @@ -1012,7 +1016,7 @@ static struct svc_xprt *svc_rdma_accept(struct svc_xprt *xprt) qp_attr.event_handler = qp_event_handler; qp_attr.qp_context = &newxprt->sc_xprt; qp_attr.cap.max_send_wr = newxprt->sc_sq_depth; - qp_attr.cap.max_recv_wr = newxprt->sc_max_requests; + qp_attr.cap.max_recv_wr = total_reqs; qp_attr.cap.max_send_sge = newxprt->sc_max_sge; qp_attr.cap.max_recv_sge = newxprt->sc_max_sge; qp_attr.sq_sig_type = IB_SIGNAL_REQ_WR; @@ -1108,7 +1112,7 @@ static struct svc_xprt *svc_rdma_accept(struct svc_xprt *xprt) newxprt->sc_cm_id->device->local_dma_lkey; /* Post receive buffers */ - for (i = 0; i < newxprt->sc_max_requests; i++) { + for (i = 0; i < total_reqs; i++) { ret = svc_rdma_post_recv(newxprt); if (ret) { dprintk("svcrdma: failure posting receive buffers\n");