Commit ed4adc07 authored by Paul Barker's avatar Paul Barker Committed by Jakub Kicinski
Browse files

net: ravb: Count packets instead of descriptors in GbEth RX path 



The units of "work done" in the RX path should be packets instead of
descriptors, as large packets can be spread over multiple descriptors.

Fixes: 1c59eb67 ("ravb: Fillup ravb_rx_gbeth() stub")
Signed-off-by: default avatarPaul Barker <paul.barker.ct@bp.renesas.com>
Reviewed-by: default avatarSergey Shtylyov <s.shtylyov@omp.ru>
Link: https://lore.kernel.org/r/20240214151204.2976-1-paul.barker.ct@bp.renesas.com


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent dc34ebd5

drivers/net/ethernet/renesas/ravb_main.c

+9 −13
Original line number Diff line number Diff line
@@ -772,29 +772,25 @@ static bool ravb_rx_gbeth(struct net_device *ndev, int *quota, int q) 
	struct ravb_rx_desc *desc;

	struct sk_buff *skb;

	dma_addr_t dma_addr;

	int rx_packets = 0;

	u8  desc_status;

	int boguscnt;

	u16 pkt_len;

	u8  die_dt;

	int entry;

	int limit;

	int i;



	entry = priv->cur_rx[q] % priv->num_rx_ring[q];

	boguscnt = priv->dirty_rx[q] + priv->num_rx_ring[q] - priv->cur_rx[q];

	limit = priv->dirty_rx[q] + priv->num_rx_ring[q] - priv->cur_rx[q];

	stats = &priv->stats[q];



	boguscnt = min(boguscnt, *quota);

	limit = boguscnt;

	desc = &priv->gbeth_rx_ring[entry];

	while (desc->die_dt != DT_FEMPTY) {

	for (i = 0; i < limit && rx_packets < *quota && desc->die_dt != DT_FEMPTY; i++) {

		/* Descriptor type must be checked before all other reads */

		dma_rmb();

		desc_status = desc->msc;

		pkt_len = le16_to_cpu(desc->ds_cc) & RX_DS;



		if (--boguscnt < 0)

			break;



		/* We use 0-byte descriptors to mark the DMA mapping errors */

		if (!pkt_len)

			continue;
@@ -820,7 +816,7 @@ static bool ravb_rx_gbeth(struct net_device *ndev, int *quota, int q) 
				skb_put(skb, pkt_len);

				skb->protocol = eth_type_trans(skb, ndev);

				napi_gro_receive(&priv->napi[q], skb);

				stats->rx_packets++;

				rx_packets++;

				stats->rx_bytes += pkt_len;

				break;

			case DT_FSTART:
@@ -848,7 +844,7 @@ static bool ravb_rx_gbeth(struct net_device *ndev, int *quota, int q) 
					eth_type_trans(priv->rx_1st_skb, ndev);

				napi_gro_receive(&priv->napi[q],

						 priv->rx_1st_skb);

				stats->rx_packets++;

				rx_packets++;

				stats->rx_bytes += pkt_len;

				break;

			}
@@ -887,9 +883,9 @@ static bool ravb_rx_gbeth(struct net_device *ndev, int *quota, int q) 
		desc->die_dt = DT_FEMPTY;

	}



	*quota -= limit - (++boguscnt);



	return boguscnt <= 0;

	stats->rx_packets += rx_packets;

	*quota -= rx_packets;

	return *quota == 0;

}



/* Packet receive function for Ethernet AVB */