[PATCH v4 1/4] net/ice: detect stopping a flow-director queue twice

[Bruce Richardson <bruce.richardson@intel.com>]

If the flow-director queue is stopped at some point during the running
of an application, the shutdown procedure for the port issues an error
as it tries to stop the queue a second time, and fails to do so. We can
eliminate this error by setting the tail-register pointer to NULL on
stop, and checking for that condition in subsequent stop calls. Since
the register pointer is set on start, any restarting of the queue will
allow a stop call to progress as normal.

Fixes: 84dc7a95a2d3 ("net/ice: enable flow director engine")
Cc: stable@dpdk.org

Signed-off-by: Bruce Richardson <bruce.richardson@intel.com>
Acked-by: Stephen Hemminger <stephen@networkplumber.org>
---
 drivers/net/ice/ice_rxtx.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/net/ice/ice_rxtx.c b/drivers/net/ice/ice_rxtx.c
index d2f9edc221..024d97cb46 100644
--- a/drivers/net/ice/ice_rxtx.c
+++ b/drivers/net/ice/ice_rxtx.c
@@ -1139,6 +1139,10 @@ ice_fdir_tx_queue_stop(struct rte_eth_dev *dev, uint16_t tx_queue_id)
 			    tx_queue_id);
 		return -EINVAL;
 	}
+	if (txq->qtx_tail == NULL) {
+		PMD_DRV_LOG(INFO, "TX queue %u not started", tx_queue_id);
+		return 0;
+	}
 	vsi = txq->vsi;
 
 	q_ids[0] = txq->reg_idx;
@@ -1153,6 +1157,7 @@ ice_fdir_tx_queue_stop(struct rte_eth_dev *dev, uint16_t tx_queue_id)
 	}
 
 	txq->tx_rel_mbufs(txq);
+	txq->qtx_tail = NULL;
 
 	return 0;
 }
-- 
2.43.0