diff mbox series

[net-next,1/9] net: enetc: consume the error RX buffer descriptors in a dedicated function

Message ID 20210331200857.3274425-2-olteanv@gmail.com (mailing list archive)
State Accepted
Commit 2fa423f5f0c6891effd4d5c8bdb91d418001da11
Delegated to: Netdev Maintainers
Headers show
Series XDP for NXP ENETC | expand

Checks

Context Check Description
netdev/apply success Patch already applied to net-next
netdev/tree_selection success Clearly marked for net-next

Commit Message

Vladimir Oltean March 31, 2021, 8:08 p.m. UTC 
From: Vladimir Oltean <vladimir.oltean@nxp.com>

We can and should check the RX BD errors before starting to build the
skb. The only apparent reason why things are done in this backwards
order is to spare one call to enetc_rxbd_next.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
---
 drivers/net/ethernet/freescale/enetc/enetc.c | 43 ++++++++++++--------
 1 file changed, 27 insertions(+), 16 deletions(-)
diff mbox series

Patch

diff --git a/drivers/net/ethernet/freescale/enetc/enetc.c b/drivers/net/ethernet/freescale/enetc/enetc.c
index 5a54976e6a28..362cfba7ce14 100644
--- a/drivers/net/ethernet/freescale/enetc/enetc.c
+++ b/drivers/net/ethernet/freescale/enetc/enetc.c
@@ -605,6 +605,28 @@  static void enetc_add_rx_buff_to_skb(struct enetc_bdr *rx_ring, int i,
 	enetc_put_rx_buff(rx_ring, rx_swbd);
 }
 
+static bool enetc_check_bd_errors_and_consume(struct enetc_bdr *rx_ring,
+					      u32 bd_status,
+					      union enetc_rx_bd **rxbd, int *i)
+{
+	if (likely(!(bd_status & ENETC_RXBD_LSTATUS(ENETC_RXBD_ERR_MASK))))
+		return false;
+
+	enetc_rxbd_next(rx_ring, rxbd, i);
+
+	while (!(bd_status & ENETC_RXBD_LSTATUS_F)) {
+		dma_rmb();
+		bd_status = le32_to_cpu((*rxbd)->r.lstatus);
+
+		enetc_rxbd_next(rx_ring, rxbd, i);
+	}
+
+	rx_ring->ndev->stats.rx_dropped++;
+	rx_ring->ndev->stats.rx_errors++;
+
+	return true;
+}
+
 #define ENETC_RXBD_BUNDLE 16 /* # of BDs to update at once */
 
 static int enetc_clean_rx_ring(struct enetc_bdr *rx_ring,
@@ -634,6 +656,11 @@  static int enetc_clean_rx_ring(struct enetc_bdr *rx_ring,
 
 		enetc_wr_reg_hot(rx_ring->idr, BIT(rx_ring->index));
 		dma_rmb(); /* for reading other rxbd fields */
+
+		if (enetc_check_bd_errors_and_consume(rx_ring, bd_status,
+						      &rxbd, &i))
+			break;
+
 		size = le16_to_cpu(rxbd->r.buf_len);
 		skb = enetc_map_rx_buff_to_skb(rx_ring, i, size);
 		if (!skb)
@@ -645,22 +672,6 @@  static int enetc_clean_rx_ring(struct enetc_bdr *rx_ring,
 
 		enetc_rxbd_next(rx_ring, &rxbd, &i);
 
-		if (unlikely(bd_status &
-			     ENETC_RXBD_LSTATUS(ENETC_RXBD_ERR_MASK))) {
-			dev_kfree_skb(skb);
-			while (!(bd_status & ENETC_RXBD_LSTATUS_F)) {
-				dma_rmb();
-				bd_status = le32_to_cpu(rxbd->r.lstatus);
-
-				enetc_rxbd_next(rx_ring, &rxbd, &i);
-			}
-
-			rx_ring->ndev->stats.rx_dropped++;
-			rx_ring->ndev->stats.rx_errors++;
-
-			break;
-		}
-
 		/* not last BD in frame? */
 		while (!(bd_status & ENETC_RXBD_LSTATUS_F)) {
 			bd_status = le32_to_cpu(rxbd->r.lstatus);