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>
diff --git a/net/rds/iw_send.c b/net/rds/iw_send.c
index 22dd38f..626290b 100644
--- a/net/rds/iw_send.c
+++ b/net/rds/iw_send.c
@@ -549,7 +549,7 @@
 			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;