RDS/IW+IB: Set the RDS_LL_SEND_FULL bit when we're throttled.

The RDS_LL_SEND_FULL bit should be set when we stop transmitted due to
flow control.  Otherwise the send worker will keep trying as opposed to
sleeping until we unthrottle.  Saves CPU.
Signed-off-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Andy Grover <andy.grover@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/rds/ib_send.c

@@ -506,7 +506,7 @@ int rds_ib_xmit(struct rds_connection *conn, struct rds_message *rm,
 			flow_controlled++;
 		}
 		if (work_alloc == 0) {
-			rds_ib_ring_unalloc(&ic->i_send_ring, work_alloc);
+			set_bit(RDS_LL_SEND_FULL, &conn->c_flags);
 			rds_ib_stats_inc(s_ib_tx_throttle);
 			ret = -ENOMEM;
 			goto out;

net/rds/iw_send.c

@@ -549,7 +549,7 @@ int rds_iw_xmit(struct rds_connection *conn, struct rds_message *rm,
 			flow_controlled++;
 		}
 		if (work_alloc == 0) {
-			rds_iw_ring_unalloc(&ic->i_send_ring, work_alloc);
+			set_bit(RDS_LL_SEND_FULL, &conn->c_flags);
 			rds_iw_stats_inc(s_iw_tx_throttle);
 			ret = -ENOMEM;
 			goto out;