Commit 8492e4f1 authored by Wei Fang's avatar Wei Fang Committed by Paolo Abeni
Browse files

net: fec: use switch statement to check the type of tx_buf 



The tx_buf has three types: FEC_TXBUF_T_SKB, FEC_TXBUF_T_XDP_NDO and
FEC_TXBUF_T_XDP_TX. Currently, the driver uses 'if...else...' statements
to check the type and perform the corresponding processing. This is very
detrimental to future expansion. To support AF_XDP zero-copy mode, two
new types will be added in the future, continuing to use 'if...else...'
would be a very bad coding style. So the 'if...else...' statements in
the current driver are replaced with switch statements.

Signed-off-by: default avatarWei Fang <wei.fang@nxp.com>
Link: https://patch.msgid.link/20260205085742.2685134-11-wei.fang@nxp.com


Signed-off-by: default avatarPaolo Abeni <pabeni@redhat.com>
parent 2dcc9347

drivers/net/ethernet/freescale/fec_main.c

+73 −61
Original line number Diff line number Diff line
@@ -1023,9 +1023,13 @@ static void fec_enet_bd_init(struct net_device *dev) 
		txq->bd.cur = bdp;



		for (i = 0; i < txq->bd.ring_size; i++) {

			struct page *page;



			/* Initialize the BD for every fragment in the page. */

			bdp->cbd_sc = cpu_to_fec16(0);

			if (txq->tx_buf[i].type == FEC_TXBUF_T_SKB) {



			switch (txq->tx_buf[i].type) {

			case FEC_TXBUF_T_SKB:

				if (bdp->cbd_bufaddr &&

				    !IS_TSO_HEADER(txq, fec32_to_cpu(bdp->cbd_bufaddr)))

					dma_unmap_single(&fep->pdev->dev,
@@ -1033,18 +1037,21 @@ static void fec_enet_bd_init(struct net_device *dev) 
							 fec16_to_cpu(bdp->cbd_datlen),

							 DMA_TO_DEVICE);

				dev_kfree_skb_any(txq->tx_buf[i].buf_p);

			} else if (txq->tx_buf[i].type == FEC_TXBUF_T_XDP_NDO) {

				break;

			case FEC_TXBUF_T_XDP_NDO:

				dma_unmap_single(&fep->pdev->dev,

						 fec32_to_cpu(bdp->cbd_bufaddr),

						 fec16_to_cpu(bdp->cbd_datlen),

						 DMA_TO_DEVICE);



				xdp_return_frame(txq->tx_buf[i].buf_p);

			} else {

				struct page *page = txq->tx_buf[i].buf_p;



				break;

			case FEC_TXBUF_T_XDP_TX:

				page = txq->tx_buf[i].buf_p;

				page_pool_put_page(pp_page_to_nmdesc(page)->pp,

						   page, 0, false);

				break;

			default:

				break;

			}



			txq->tx_buf[i].buf_p = NULL;
@@ -1510,39 +1517,69 @@ fec_enet_tx_queue(struct net_device *ndev, u16 queue_id, int budget) 
			break;



		index = fec_enet_get_bd_index(bdp, &txq->bd);

		frame_len = fec16_to_cpu(bdp->cbd_datlen);



		if (txq->tx_buf[index].type == FEC_TXBUF_T_SKB) {

			skb = txq->tx_buf[index].buf_p;

		switch (txq->tx_buf[index].type) {

		case FEC_TXBUF_T_SKB:

			if (bdp->cbd_bufaddr &&

			    !IS_TSO_HEADER(txq, fec32_to_cpu(bdp->cbd_bufaddr)))

				dma_unmap_single(&fep->pdev->dev,

						 fec32_to_cpu(bdp->cbd_bufaddr),

						 fec16_to_cpu(bdp->cbd_datlen),

						 DMA_TO_DEVICE);

						 frame_len, DMA_TO_DEVICE);



			bdp->cbd_bufaddr = cpu_to_fec32(0);

			skb = txq->tx_buf[index].buf_p;

			if (!skb)

				goto tx_buf_done;

		} else {



			frame_len = skb->len;



			/* NOTE: SKBTX_IN_PROGRESS being set does not imply it's we who

			 * are to time stamp the packet, so we still need to check time

			 * stamping enabled flag.

			 */

			if (unlikely(skb_shinfo(skb)->tx_flags & SKBTX_IN_PROGRESS &&

				     fep->hwts_tx_en) && fep->bufdesc_ex) {

				struct bufdesc_ex *ebdp = (struct bufdesc_ex *)bdp;

				struct skb_shared_hwtstamps shhwtstamps;



				fec_enet_hwtstamp(fep, fec32_to_cpu(ebdp->ts), &shhwtstamps);

				skb_tstamp_tx(skb, &shhwtstamps);

			}



			/* Free the sk buffer associated with this last transmit */

			napi_consume_skb(skb, budget);

			break;

		case FEC_TXBUF_T_XDP_NDO:

			/* Tx processing cannot call any XDP (or page pool) APIs if

			 * the "budget" is 0. Because NAPI is called with budget of

			 * 0 (such as netpoll) indicates we may be in an IRQ context,

			 * however, we can't use the page pool from IRQ context.

			 */

			if (unlikely(!budget))

				break;

				goto out;



			if (txq->tx_buf[index].type == FEC_TXBUF_T_XDP_NDO) {

			xdpf = txq->tx_buf[index].buf_p;

			dma_unmap_single(&fep->pdev->dev,

					 fec32_to_cpu(bdp->cbd_bufaddr),

						 fec16_to_cpu(bdp->cbd_datlen),

						 DMA_TO_DEVICE);

			} else {

				page = txq->tx_buf[index].buf_p;

			}

					 frame_len,  DMA_TO_DEVICE);

			bdp->cbd_bufaddr = cpu_to_fec32(0);

			xdp_return_frame_rx_napi(xdpf);

			break;

		case FEC_TXBUF_T_XDP_TX:

			if (unlikely(!budget))

				goto out;



			bdp->cbd_bufaddr = cpu_to_fec32(0);

			frame_len = fec16_to_cpu(bdp->cbd_datlen);

			page = txq->tx_buf[index].buf_p;

			/* The dma_sync_size = 0 as XDP_TX has already synced

			 * DMA for_device

			 */

			page_pool_put_page(pp_page_to_nmdesc(page)->pp, page,

					   0, true);

			break;

		default:

			break;

		}



		/* Check for errors. */
@@ -1562,10 +1599,6 @@ fec_enet_tx_queue(struct net_device *ndev, u16 queue_id, int budget) 
				ndev->stats.tx_carrier_errors++;

		} else {

			ndev->stats.tx_packets++;



			if (txq->tx_buf[index].type == FEC_TXBUF_T_SKB)

				ndev->stats.tx_bytes += skb->len;

			else

			ndev->stats.tx_bytes += frame_len;

		}
@@ -1575,30 +1608,6 @@ fec_enet_tx_queue(struct net_device *ndev, u16 queue_id, int budget) 
		if (status & BD_ENET_TX_DEF)

			ndev->stats.collisions++;



		if (txq->tx_buf[index].type == FEC_TXBUF_T_SKB) {

			/* NOTE: SKBTX_IN_PROGRESS being set does not imply it's we who

			 * are to time stamp the packet, so we still need to check time

			 * stamping enabled flag.

			 */

			if (unlikely(skb_shinfo(skb)->tx_flags & SKBTX_IN_PROGRESS &&

				     fep->hwts_tx_en) && fep->bufdesc_ex) {

				struct skb_shared_hwtstamps shhwtstamps;

				struct bufdesc_ex *ebdp = (struct bufdesc_ex *)bdp;



				fec_enet_hwtstamp(fep, fec32_to_cpu(ebdp->ts), &shhwtstamps);

				skb_tstamp_tx(skb, &shhwtstamps);

			}



			/* Free the sk buffer associated with this last transmit */

			napi_consume_skb(skb, budget);

		} else if (txq->tx_buf[index].type == FEC_TXBUF_T_XDP_NDO) {

			xdp_return_frame_rx_napi(xdpf);

		} else { /* recycle pages of XDP_TX frames */

			/* The dma_sync_size = 0 as XDP_TX has already synced DMA for_device */

			page_pool_put_page(pp_page_to_nmdesc(page)->pp, page,

					   0, true);

		}



		txq->tx_buf[index].buf_p = NULL;

		/* restore default tx buffer type: FEC_TXBUF_T_SKB */

		txq->tx_buf[index].type = FEC_TXBUF_T_SKB;
@@ -1622,6 +1631,8 @@ fec_enet_tx_queue(struct net_device *ndev, u16 queue_id, int budget) 
		}

	}



out:



	/* ERR006358: Keep the transmitter going */

	if (bdp != txq->bd.cur &&

	    readl(txq->bd.reg_desc_active) == 0)
@@ -3415,6 +3426,7 @@ static void fec_enet_free_buffers(struct net_device *ndev) 
	unsigned int i;

	struct fec_enet_priv_tx_q *txq;

	struct fec_enet_priv_rx_q *rxq;

	struct page *page;

	unsigned int q;



	for (q = 0; q < fep->num_rx_queues; q++) {
@@ -3438,20 +3450,20 @@ static void fec_enet_free_buffers(struct net_device *ndev) 
			kfree(txq->tx_bounce[i]);

			txq->tx_bounce[i] = NULL;



			if (!txq->tx_buf[i].buf_p) {

				txq->tx_buf[i].type = FEC_TXBUF_T_SKB;

				continue;

			}



			if (txq->tx_buf[i].type == FEC_TXBUF_T_SKB) {

			switch (txq->tx_buf[i].type) {

			case FEC_TXBUF_T_SKB:

				dev_kfree_skb(txq->tx_buf[i].buf_p);

			} else if (txq->tx_buf[i].type == FEC_TXBUF_T_XDP_NDO) {

				break;

			case FEC_TXBUF_T_XDP_NDO:

				xdp_return_frame(txq->tx_buf[i].buf_p);

			} else {

				struct page *page = txq->tx_buf[i].buf_p;



				break;

			case FEC_TXBUF_T_XDP_TX:

				page = txq->tx_buf[i].buf_p;

				page_pool_put_page(pp_page_to_nmdesc(page)->pp,

						   page, 0, false);

				break;

			default:

				break;

			}



			txq->tx_buf[i].buf_p = NULL;