diff options
| author | Håkon Bugge <haakon.bugge@oracle.com> | 2021-03-31 20:43:14 +0200 |
|---|---|---|
| committer | Jason Gunthorpe <jgg@nvidia.com> | 2021-04-12 19:51:48 -0300 |
| commit | 5aa54bd28ce2b066d82cdd515269b9d562bd6e66 (patch) | |
| tree | 027b8877446b4c7af02cc319d231d32a754161ff /net/rds | |
| parent | 3aeffc46afde05140551abb49efaa4563adba38c (diff) | |
| download | linux-5aa54bd28ce2b066d82cdd515269b9d562bd6e66.tar.gz | |
rds: ib: Remove two ib_modify_qp() calls
For some HCAs, ib_modify_qp() is an expensive operation running
virtualized.
For both the active and passive side, the QP returned by the CM has the
state set to RTS, so no need for this excess RTS -> RTS transition. With
IB Core's ability to set the RNR Retry timer, we use this interface to
shave off another ib_modify_qp().
Fixes: ec16227e1414 ("RDS/IB: Infiniband transport")
Link: https://lore.kernel.org/r/1617216194-12890-3-git-send-email-haakon.bugge@oracle.com
Signed-off-by: Håkon Bugge <haakon.bugge@oracle.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Diffstat (limited to 'net/rds')
| -rw-r--r-- | net/rds/ib_cm.c | 35 | ||||
| -rw-r--r-- | net/rds/rdma_transport.c | 1 |
2 files changed, 2 insertions, 34 deletions
diff --git a/net/rds/ib_cm.c b/net/rds/ib_cm.c index f5cbe963cd8f7..26b069e1999df 100644 --- a/net/rds/ib_cm.c +++ b/net/rds/ib_cm.c @@ -68,31 +68,6 @@ static void rds_ib_set_flow_control(struct rds_connection *conn, u32 credits) } /* - * Tune RNR behavior. Without flow control, we use a rather - * low timeout, but not the absolute minimum - this should - * be tunable. - * - * We already set the RNR retry count to 7 (which is the - * smallest infinite number :-) above. - * If flow control is off, we want to change this back to 0 - * so that we learn quickly when our credit accounting is - * buggy. - * - * Caller passes in a qp_attr pointer - don't waste stack spacv - * by allocation this twice. - */ -static void -rds_ib_tune_rnr(struct rds_ib_connection *ic, struct ib_qp_attr *attr) -{ - int ret; - - attr->min_rnr_timer = IB_RNR_TIMER_000_32; - ret = ib_modify_qp(ic->i_cm_id->qp, attr, IB_QP_MIN_RNR_TIMER); - if (ret) - printk(KERN_NOTICE "ib_modify_qp(IB_QP_MIN_RNR_TIMER): err=%d\n", -ret); -} - -/* * Connection established. * We get here for both outgoing and incoming connection. */ @@ -100,7 +75,6 @@ void rds_ib_cm_connect_complete(struct rds_connection *conn, struct rdma_cm_even { struct rds_ib_connection *ic = conn->c_transport_data; const union rds_ib_conn_priv *dp = NULL; - struct ib_qp_attr qp_attr; __be64 ack_seq = 0; __be32 credit = 0; u8 major = 0; @@ -168,14 +142,6 @@ void rds_ib_cm_connect_complete(struct rds_connection *conn, struct rdma_cm_even * the posted credit count. */ rds_ib_recv_refill(conn, 1, GFP_KERNEL); - /* Tune RNR behavior */ - rds_ib_tune_rnr(ic, &qp_attr); - - qp_attr.qp_state = IB_QPS_RTS; - err = ib_modify_qp(ic->i_cm_id->qp, &qp_attr, IB_QP_STATE); - if (err) - printk(KERN_NOTICE "ib_modify_qp(IB_QP_STATE, RTS): err=%d\n", err); - /* update ib_device with this local ipaddr */ err = rds_ib_update_ipaddr(ic->rds_ibdev, &conn->c_laddr); if (err) @@ -947,6 +913,7 @@ int rds_ib_cm_handle_connect(struct rdma_cm_id *cm_id, event->param.conn.responder_resources, event->param.conn.initiator_depth, isv6); + rdma_set_min_rnr_timer(cm_id, IB_RNR_TIMER_000_32); /* rdma_accept() calls rdma_reject() internally if it fails */ if (rdma_accept(cm_id, &conn_param)) rds_ib_conn_error(conn, "rdma_accept failed\n"); diff --git a/net/rds/rdma_transport.c b/net/rds/rdma_transport.c index 5f741e51b4baa..a9e4ff948a7d6 100644 --- a/net/rds/rdma_transport.c +++ b/net/rds/rdma_transport.c @@ -87,6 +87,7 @@ static int rds_rdma_cm_event_handler_cmn(struct rdma_cm_id *cm_id, case RDMA_CM_EVENT_ADDR_RESOLVED: rdma_set_service_type(cm_id, conn->c_tos); + rdma_set_min_rnr_timer(cm_id, IB_RNR_TIMER_000_32); /* XXX do we need to clean up if this fails? */ ret = rdma_resolve_route(cm_id, RDS_RDMA_RESOLVE_TIMEOUT_MS); |