From 75891f502f5fc70f52a01af5b924384ed4866907 Mon Sep 17 00:00:00 2001 From: Trond Myklebust Date: Mon, 3 Sep 2018 17:37:36 -0400 Subject: SUNRPC: Support for congestion control when queuing is enabled Both RDMA and UDP transports require the request to get a "congestion control" credit before they can be transmitted. Right now, this is done when the request locks the socket. We'd like it to happen when a request attempts to be transmitted for the first time. In order to support retransmission of requests that already hold such credits, we also want to ensure that they get queued first, so that we don't deadlock with requests that have yet to obtain a credit. Signed-off-by: Trond Myklebust --- net/sunrpc/xprtrdma/backchannel.c | 3 +++ net/sunrpc/xprtrdma/transport.c | 3 +++ 2 files changed, 6 insertions(+) (limited to 'net/sunrpc/xprtrdma') diff --git a/net/sunrpc/xprtrdma/backchannel.c b/net/sunrpc/xprtrdma/backchannel.c index ed58761e6b23..e7c445cee16f 100644 --- a/net/sunrpc/xprtrdma/backchannel.c +++ b/net/sunrpc/xprtrdma/backchannel.c @@ -200,6 +200,9 @@ int xprt_rdma_bc_send_reply(struct rpc_rqst *rqst) if (!xprt_connected(rqst->rq_xprt)) goto drop_connection; + if (!xprt_request_get_cong(rqst->rq_xprt, rqst)) + return -EBADSLT; + rc = rpcrdma_bc_marshal_reply(rqst); if (rc < 0) goto failed_marshal; diff --git a/net/sunrpc/xprtrdma/transport.c b/net/sunrpc/xprtrdma/transport.c index fa684bf4d090..9ff322e53f37 100644 --- a/net/sunrpc/xprtrdma/transport.c +++ b/net/sunrpc/xprtrdma/transport.c @@ -721,6 +721,9 @@ xprt_rdma_send_request(struct rpc_rqst *rqst, struct rpc_task *task) if (!xprt_connected(xprt)) goto drop_connection; + if (!xprt_request_get_cong(xprt, rqst)) + return -EBADSLT; + rc = rpcrdma_marshal_req(r_xprt, rqst); if (rc < 0) goto failed_marshal; -- cgit v1.2.3