Hi Jakub,

On 29/07/23 5:54 am, Jakub Kicinski wrote:

On Thu, 27 Jul 2023 16:58:23 +0530 MD Danish Anwar wrote:

quoted

+static int emac_tx_complete_packets(struct prueth_emac *emac, int chn,
+				    int budget)
+{
+	struct net_device *ndev = emac->ndev;
+	struct cppi5_host_desc_t *desc_tx;
+	struct netdev_queue *netif_txq;
+	struct prueth_tx_chn *tx_chn;
+	unsigned int total_bytes = 0;
+	struct sk_buff *skb;
+	dma_addr_t desc_dma;
+	int res, num_tx = 0;
+	void **swdata;
+
+	tx_chn = &emac->tx_chns[chn];
+
+	while (budget) {
+		res = k3_udma_glue_pop_tx_chn(tx_chn->tx_chn, &desc_dma);
+		if (res == -ENODATA)
+			break;

You shouldn't limit the number of serviced packets to budget for Tx
NAPI.

https://docs.kernel.org/next/networking/napi.html#driver-api

quoted

+	skb->dev = ndev;
+	if (!netif_running(skb->dev)) {
+		dev_kfree_skb_any(skb);
+		return 0;
+	}

why do you check if the interface is running?
If a packet arrives, it means the interface is running..

Sure, I will drop this if condition.

quoted

+drop_free_descs:
+	prueth_xmit_free(tx_chn, first_desc);
+drop_stop_q:
+	netif_tx_stop_queue(netif_txq);

Do not stop the queue on DMA errors. If the queue is empty nothing
will wake it up. Queue should only be stopped based on occupancy.

Sure, I will try to make sure we only stop queue based on occupancy.

quoted

+	dev_kfree_skb_any(skb);
+
+	/* error */
+	ndev->stats.tx_dropped++;
+	netdev_err(ndev, "tx: error: %d\n", ret);
+
+	return ret;

-- 
Thanks and Regards,
Danish.