From 97cc3264508f33783ba21573204d7e0bf5b197e7 Mon Sep 17 00:00:00 2001 From: Chuck Lever Date: Tue, 20 Mar 2018 17:05:15 -0400 Subject: [PATCH] svcrdma: Consult max_qp_init_rd_atom when accepting connections The target needs to return the lesser of the client's Inbound RDMA Read Queue Depth (IRD), provided in the connection parameters, and the local device's Outbound RDMA Read Queue Depth (ORD). The latter limit is max_qp_init_rd_atom, not max_qp_rd_atom. The svcrdma_ord value caps the ORD value for iWARP transports, which do not exchange ORD/IRD values at connection time. Since no other Linux kernel RDMA-enabled storage target sees fit to provide this cap, I'm removing it here too. initiator_depth is a u8, so ensure the computed ORD value does not overflow that field. Signed-off-by: Chuck Lever Signed-off-by: J. Bruce Fields --- include/linux/sunrpc/svc_rdma.h | 3 --- net/sunrpc/xprtrdma/svc_rdma.c | 4 ++-- net/sunrpc/xprtrdma/svc_rdma_transport.c | 22 +++++++++------------- 3 files changed, 11 insertions(+), 18 deletions(-) diff --git a/include/linux/sunrpc/svc_rdma.h b/include/linux/sunrpc/svc_rdma.h index 4b731b046bcd..7337e1221590 100644 --- a/include/linux/sunrpc/svc_rdma.h +++ b/include/linux/sunrpc/svc_rdma.h @@ -132,9 +132,6 @@ struct svcxprt_rdma { #define RDMAXPRT_CONN_PENDING 3 #define RPCRDMA_LISTEN_BACKLOG 10 -/* The default ORD value is based on two outstanding full-size writes with a - * page size of 4k, or 32k * 2 ops / 4k = 16 outstanding RDMA_READ. */ -#define RPCRDMA_ORD (64/4) #define RPCRDMA_MAX_REQUESTS 32 /* Typical ULP usage of BC requests is NFSv4.1 backchannel. Our diff --git a/net/sunrpc/xprtrdma/svc_rdma.c b/net/sunrpc/xprtrdma/svc_rdma.c index a4a8f6989ee7..dd8a431dc2ae 100644 --- a/net/sunrpc/xprtrdma/svc_rdma.c +++ b/net/sunrpc/xprtrdma/svc_rdma.c @@ -51,9 +51,9 @@ #define RPCDBG_FACILITY RPCDBG_SVCXPRT /* RPC/RDMA parameters */ -unsigned int svcrdma_ord = RPCRDMA_ORD; +unsigned int svcrdma_ord = 16; /* historical default */ static unsigned int min_ord = 1; -static unsigned int max_ord = 4096; +static unsigned int max_ord = 255; unsigned int svcrdma_max_requests = RPCRDMA_MAX_REQUESTS; unsigned int svcrdma_max_bc_requests = RPCRDMA_MAX_BC_REQUESTS; static unsigned int min_max_requests = 4; diff --git a/net/sunrpc/xprtrdma/svc_rdma_transport.c b/net/sunrpc/xprtrdma/svc_rdma_transport.c index 135ae175ca8e..7b2f4d3a2543 100644 --- a/net/sunrpc/xprtrdma/svc_rdma_transport.c +++ b/net/sunrpc/xprtrdma/svc_rdma_transport.c @@ -762,13 +762,6 @@ static struct svc_xprt *svc_rdma_accept(struct svc_xprt *xprt) if (!svc_rdma_prealloc_ctxts(newxprt)) goto errout; - /* - * Limit ORD based on client limit, local device limit, and - * configured svcrdma limit. - */ - newxprt->sc_ord = min_t(size_t, dev->attrs.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(dev, 0); if (IS_ERR(newxprt->sc_pd)) { dprintk("svcrdma: error creating PD for connect request\n"); @@ -843,15 +836,18 @@ static struct svc_xprt *svc_rdma_accept(struct svc_xprt *xprt) set_bit(RDMAXPRT_CONN_PENDING, &newxprt->sc_flags); memset(&conn_param, 0, sizeof conn_param); conn_param.responder_resources = 0; - conn_param.initiator_depth = newxprt->sc_ord; + conn_param.initiator_depth = min_t(int, newxprt->sc_ord, + dev->attrs.max_qp_init_rd_atom); + if (!conn_param.initiator_depth) { + dprintk("svcrdma: invalid ORD setting\n"); + ret = -EINVAL; + goto errout; + } conn_param.private_data = &pmsg; conn_param.private_data_len = sizeof(pmsg); ret = rdma_accept(newxprt->sc_cm_id, &conn_param); - if (ret) { - dprintk("svcrdma: failed to accept new connection, ret=%d\n", - ret); + if (ret) goto errout; - } dprintk("svcrdma: new connection %p accepted:\n", newxprt); sap = (struct sockaddr *)&newxprt->sc_cm_id->route.addr.src_addr; @@ -862,7 +858,7 @@ static struct svc_xprt *svc_rdma_accept(struct svc_xprt *xprt) dprintk(" sq_depth : %d\n", newxprt->sc_sq_depth); dprintk(" rdma_rw_ctxs : %d\n", ctxts); dprintk(" max_requests : %d\n", newxprt->sc_max_requests); - dprintk(" ord : %d\n", newxprt->sc_ord); + dprintk(" ord : %d\n", conn_param.initiator_depth); return &newxprt->sc_xprt;