[Intel-wired-lan] [PATCH] ixgbe: Fix ixgbe TX hangs with XDP_TX beyond queue limit.

[Radoslaw Tyl]

We have Tx hang when number tx and xdp queues are more than 64.
In XDP always is MTQC == 0x0 (64TxQs). We need more  space for Tx queues.

Signed-off-by: Radoslaw Tyl <radoslawx.tyl at intel.com>
---
 drivers/net/ethernet/intel/ixgbe/ixgbe_main.c | 14 ++++++++++----
 1 file changed, 10 insertions(+), 4 deletions(-)

diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
index 604282f..e227549 100644
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
@@ -3577,12 +3577,18 @@ static void ixgbe_setup_mtqc(struct ixgbe_adapter *adapter)
 		else
 			mtqc |= IXGBE_MTQC_64VF;
 	} else {
-		if (tcs > 4)
+		if (tcs > 4) {
 			mtqc = IXGBE_MTQC_RT_ENA | IXGBE_MTQC_8TC_8TQ;
-		else if (tcs > 1)
+		} else if (tcs > 1) {
 			mtqc = IXGBE_MTQC_RT_ENA | IXGBE_MTQC_4TC_4TQ;
-		else
-			mtqc = IXGBE_MTQC_64Q_1PB;
+		} else {
+			u8 max_txq = adapter->num_tx_queues +
+				adapter->num_xdp_queues;
+			if (max_txq > 63)
+				mtqc = IXGBE_MTQC_RT_ENA | IXGBE_MTQC_4TC_4TQ;
+			else
+				mtqc = IXGBE_MTQC_64Q_1PB;
+		}
 	}
 
 	IXGBE_WRITE_REG(hw, IXGBE_MTQC, mtqc);
-- 
1.8.3.1

--------------------------------------------------------------------

Intel Technology Poland sp. z o.o.
ul. Slowackiego 173 | 80-298 Gdansk | Sad Rejonowy Gdansk Polnoc | VII Wydzial Gospodarczy Krajowego Rejestru Sadowego - KRS 101882 | NIP 957-07-52-316 | Kapital zakladowy 200.000 PLN.

Ta wiadomosc wraz z zalacznikami jest przeznaczona dla okreslonego adresata i moze zawierac informacje poufne. W razie przypadkowego otrzymania tej wiadomosci, prosimy o powiadomienie nadawcy oraz trwale jej usuniecie; jakiekolwiek
przegladanie lub rozpowszechnianie jest zabronione.
This e-mail and any attachments may contain confidential material for the sole use of the intended recipient(s). If you are not the intended recipient, please contact the sender and delete all copies; any review or distribution by
others is strictly prohibited.