[Intel-wired-lan] [PATCH] ixgbe: reset next_to_clean and next_to_use when we reset the head and tail

[Sebastian Basierski]

Only reset the next_to_clean and next_to_use values when we are resetting
the head and tail hardware registers.  This way we can avoid having
multiple functions doing the reset work and can more easily track the
correlation between the registers and these values.

Signed-off-by: Sebastian Basierski <sebastianx.basierski at intel.com>
---
 drivers/net/ethernet/intel/ixgbe/ixgbe_main.c | 25 +++++++++----------
 1 file changed, 12 insertions(+), 13 deletions(-)

diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
index 27a8546c88b2..0e83f5e8973d 100644
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
@@ -3482,10 +3482,16 @@ void ixgbe_configure_tx_ring(struct ixgbe_adapter *adapter,
 	IXGBE_WRITE_REG(hw, IXGBE_TDBAH(reg_idx), (tdba >> 32));
 	IXGBE_WRITE_REG(hw, IXGBE_TDLEN(reg_idx),
 			ring->count * sizeof(union ixgbe_adv_tx_desc));
+
+	/* reset head and tail pointers */
 	IXGBE_WRITE_REG(hw, IXGBE_TDH(reg_idx), 0);
 	IXGBE_WRITE_REG(hw, IXGBE_TDT(reg_idx), 0);
 	ring->tail = adapter->io_addr + IXGBE_TDT(reg_idx);
 
+	/* reset ntu and ntc to place SW in sync with hardwdare */
+	ring->next_to_clean = 0;
+	ring->next_to_use = 0;
+
 	/*
 	 * set WTHRESH to encourage burst writeback, it should not be set
 	 * higher than 1 when:
@@ -4046,10 +4052,16 @@ void ixgbe_configure_rx_ring(struct ixgbe_adapter *adapter,
 	/* Force flushing of IXGBE_RDLEN to prevent MDD */
 	IXGBE_WRITE_FLUSH(hw);
 
+	/* reset head and tail pointers */
 	IXGBE_WRITE_REG(hw, IXGBE_RDH(reg_idx), 0);
 	IXGBE_WRITE_REG(hw, IXGBE_RDT(reg_idx), 0);
 	ring->tail = adapter->io_addr + IXGBE_RDT(reg_idx);
 
+	/* reset ntu and ntc to place SW in sync with hardwdare */
+	ring->next_to_clean = 0;
+	ring->next_to_use = 0;
+	ring->next_to_alloc = 0;
+
 	ixgbe_configure_srrctl(adapter, ring);
 	ixgbe_configure_rscctl(adapter, ring);
 
@@ -5238,10 +5250,6 @@ static void ixgbe_clean_rx_ring(struct ixgbe_ring *rx_ring)
 			rx_buffer = rx_ring->rx_buffer_info;
 		}
 	}
-
-	rx_ring->next_to_alloc = 0;
-	rx_ring->next_to_clean = 0;
-	rx_ring->next_to_use = 0;
 }
 
 static int ixgbe_fwd_ring_up(struct ixgbe_adapter *adapter,
@@ -5933,10 +5941,6 @@ static void ixgbe_clean_tx_ring(struct ixgbe_ring *tx_ring)
 	/* reset BQL for queue */
 	if (!ring_is_xdp(tx_ring))
 		netdev_tx_reset_queue(txring_txq(tx_ring));
-
-	/* reset next_to_use and next_to_clean */
-	tx_ring->next_to_use = 0;
-	tx_ring->next_to_clean = 0;
 }
 
 /**
@@ -6369,8 +6373,6 @@ int ixgbe_setup_tx_resources(struct ixgbe_ring *tx_ring)
 	if (!tx_ring->desc)
 		goto err;
 
-	tx_ring->next_to_use = 0;
-	tx_ring->next_to_clean = 0;
 	return 0;
 
 err:
@@ -6463,9 +6465,6 @@ int ixgbe_setup_rx_resources(struct ixgbe_adapter *adapter,
 	if (!rx_ring->desc)
 		goto err;
 
-	rx_ring->next_to_clean = 0;
-	rx_ring->next_to_use = 0;
-
 	/* XDP RX-queue info */
 	if (xdp_rxq_info_reg(&rx_ring->xdp_rxq, adapter->netdev,
 			     rx_ring->queue_index) < 0)
-- 
2.17.1