From: Chuck Lever chuck.lever@oracle.com
[ Upstream commit 98ef77d1aaa7a2f4e1b2a721faa084222021fda7 ]
Eli Dorfman reports that after a series of idle disconnects, an RPC/RDMA transport becomes unusable (rdma_create_qp returns -ENOMEM). Problem was tracked down to increasing Send Queue size after each reconnect.
The rdma_create_qp() API does not promise to leave its @qp_init_attr parameter unaltered. In fact, some drivers do modify one or more of its fields. Thus our calls to rdma_create_qp must use a fresh copy of ib_qp_init_attr each time.
This fix is appropriate for kernels dating back to late 2007, though it will have to be adapted, as the connect code has changed over the years.
Reported-by: Eli Dorfman eli@vastdata.com Signed-off-by: Chuck Lever chuck.lever@oracle.com Signed-off-by: Anna Schumaker Anna.Schumaker@Netapp.com Signed-off-by: Sasha Levin sashal@kernel.org --- net/sunrpc/xprtrdma/verbs.c | 26 ++++++++++++++------------ 1 file changed, 14 insertions(+), 12 deletions(-)
diff --git a/net/sunrpc/xprtrdma/verbs.c b/net/sunrpc/xprtrdma/verbs.c index 805b1f35e1caa..2bd9b4de0e325 100644 --- a/net/sunrpc/xprtrdma/verbs.c +++ b/net/sunrpc/xprtrdma/verbs.c @@ -605,10 +605,10 @@ void rpcrdma_ep_destroy(struct rpcrdma_xprt *r_xprt) * Unlike a normal reconnection, a fresh PD and a new set * of MRs and buffers is needed. */ -static int -rpcrdma_ep_recreate_xprt(struct rpcrdma_xprt *r_xprt, - struct rpcrdma_ep *ep, struct rpcrdma_ia *ia) +static int rpcrdma_ep_recreate_xprt(struct rpcrdma_xprt *r_xprt, + struct ib_qp_init_attr *qp_init_attr) { + struct rpcrdma_ia *ia = &r_xprt->rx_ia; int rc, err;
trace_xprtrdma_reinsert(r_xprt); @@ -625,7 +625,7 @@ rpcrdma_ep_recreate_xprt(struct rpcrdma_xprt *r_xprt, }
rc = -ENETUNREACH; - err = rdma_create_qp(ia->ri_id, ia->ri_pd, &ep->rep_attr); + err = rdma_create_qp(ia->ri_id, ia->ri_pd, qp_init_attr); if (err) { pr_err("rpcrdma: rdma_create_qp returned %d\n", err); goto out3; @@ -642,16 +642,16 @@ rpcrdma_ep_recreate_xprt(struct rpcrdma_xprt *r_xprt, return rc; }
-static int -rpcrdma_ep_reconnect(struct rpcrdma_xprt *r_xprt, struct rpcrdma_ep *ep, - struct rpcrdma_ia *ia) +static int rpcrdma_ep_reconnect(struct rpcrdma_xprt *r_xprt, + struct ib_qp_init_attr *qp_init_attr) { + struct rpcrdma_ia *ia = &r_xprt->rx_ia; struct rdma_cm_id *id, *old; int err, rc;
trace_xprtrdma_reconnect(r_xprt);
- rpcrdma_ep_disconnect(ep, ia); + rpcrdma_ep_disconnect(&r_xprt->rx_ep, ia);
rc = -EHOSTUNREACH; id = rpcrdma_create_id(r_xprt, ia); @@ -673,7 +673,7 @@ rpcrdma_ep_reconnect(struct rpcrdma_xprt *r_xprt, struct rpcrdma_ep *ep, goto out_destroy; }
- err = rdma_create_qp(id, ia->ri_pd, &ep->rep_attr); + err = rdma_create_qp(id, ia->ri_pd, qp_init_attr); if (err) goto out_destroy;
@@ -698,25 +698,27 @@ rpcrdma_ep_connect(struct rpcrdma_ep *ep, struct rpcrdma_ia *ia) struct rpcrdma_xprt *r_xprt = container_of(ia, struct rpcrdma_xprt, rx_ia); struct rpc_xprt *xprt = &r_xprt->rx_xprt; + struct ib_qp_init_attr qp_init_attr; int rc;
retry: + memcpy(&qp_init_attr, &ep->rep_attr, sizeof(qp_init_attr)); switch (ep->rep_connected) { case 0: dprintk("RPC: %s: connecting...\n", __func__); - rc = rdma_create_qp(ia->ri_id, ia->ri_pd, &ep->rep_attr); + rc = rdma_create_qp(ia->ri_id, ia->ri_pd, &qp_init_attr); if (rc) { rc = -ENETUNREACH; goto out_noupdate; } break; case -ENODEV: - rc = rpcrdma_ep_recreate_xprt(r_xprt, ep, ia); + rc = rpcrdma_ep_recreate_xprt(r_xprt, &qp_init_attr); if (rc) goto out_noupdate; break; default: - rc = rpcrdma_ep_reconnect(r_xprt, ep, ia); + rc = rpcrdma_ep_reconnect(r_xprt, &qp_init_attr); if (rc) goto out; }