enetc: Clean up Rx BD iteration
authorClaudiu Manoil <claudiu.manoil@nxp.com>
Tue, 10 Mar 2020 12:51:23 +0000 (14:51 +0200)
committerDavid S. Miller <davem@davemloft.net>
Tue, 10 Mar 2020 22:48:54 +0000 (15:48 -0700)
Improve maintainability of the code iterating the Rx buffer
descriptors to prepare it to support iterating extended Rx BD
descriptors as well.
Don't increment by one the h/w descriptor pointers explicitly,
provide an iterator that takes care of the h/w details.

Signed-off-by: Claudiu Manoil <claudiu.manoil@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
drivers/net/ethernet/freescale/enetc/enetc.c
drivers/net/ethernet/freescale/enetc/enetc.h

index 1f79e36116a39654da967e83fd2f470499af7989..f1bbaef428c0126378ef786a7d0c865a912d36b5 100644 (file)
@@ -451,7 +451,7 @@ static int enetc_refill_rx_ring(struct enetc_bdr *rx_ring, const int buff_cnt)
 
        i = rx_ring->next_to_use;
        rx_swbd = &rx_ring->rx_swbd[i];
-       rxbd = ENETC_RXBD(*rx_ring, i);
+       rxbd = enetc_rxbd(rx_ring, i);
 
        for (j = 0; j < buff_cnt; j++) {
                /* try reuse page */
@@ -468,13 +468,12 @@ static int enetc_refill_rx_ring(struct enetc_bdr *rx_ring, const int buff_cnt)
                /* clear 'R" as well */
                rxbd->r.lstatus = 0;
 
+               rxbd = enetc_rxbd_next(rx_ring, rxbd, i);
                rx_swbd++;
-               rxbd++;
                i++;
                if (unlikely(i == rx_ring->bd_count)) {
                        i = 0;
                        rx_swbd = rx_ring->rx_swbd;
-                       rxbd = ENETC_RXBD(*rx_ring, 0);
                }
        }
 
@@ -655,7 +654,7 @@ static int enetc_clean_rx_ring(struct enetc_bdr *rx_ring,
                        cleaned_cnt -= count;
                }
 
-               rxbd = ENETC_RXBD(*rx_ring, i);
+               rxbd = enetc_rxbd(rx_ring, i);
                bd_status = le32_to_cpu(rxbd->r.lstatus);
                if (!bd_status)
                        break;
@@ -670,12 +669,10 @@ static int enetc_clean_rx_ring(struct enetc_bdr *rx_ring,
                enetc_get_offloads(rx_ring, rxbd, skb);
 
                cleaned_cnt++;
-               rxbd++;
-               i++;
-               if (unlikely(i == rx_ring->bd_count)) {
+
+               rxbd = enetc_rxbd_next(rx_ring, rxbd, i);
+               if (unlikely(++i == rx_ring->bd_count))
                        i = 0;
-                       rxbd = ENETC_RXBD(*rx_ring, 0);
-               }
 
                if (unlikely(bd_status &
                             ENETC_RXBD_LSTATUS(ENETC_RXBD_ERR_MASK))) {
@@ -683,12 +680,10 @@ static int enetc_clean_rx_ring(struct enetc_bdr *rx_ring,
                        while (!(bd_status & ENETC_RXBD_LSTATUS_F)) {
                                dma_rmb();
                                bd_status = le32_to_cpu(rxbd->r.lstatus);
-                               rxbd++;
-                               i++;
-                               if (unlikely(i == rx_ring->bd_count)) {
+
+                               rxbd = enetc_rxbd_next(rx_ring, rxbd, i);
+                               if (unlikely(++i == rx_ring->bd_count))
                                        i = 0;
-                                       rxbd = ENETC_RXBD(*rx_ring, 0);
-                               }
                        }
 
                        rx_ring->ndev->stats.rx_dropped++;
@@ -710,12 +705,10 @@ static int enetc_clean_rx_ring(struct enetc_bdr *rx_ring,
                        enetc_add_rx_buff_to_skb(rx_ring, i, size, skb);
 
                        cleaned_cnt++;
-                       rxbd++;
-                       i++;
-                       if (unlikely(i == rx_ring->bd_count)) {
+
+                       rxbd = enetc_rxbd_next(rx_ring, rxbd, i);
+                       if (unlikely(++i == rx_ring->bd_count))
                                i = 0;
-                               rxbd = ENETC_RXBD(*rx_ring, 0);
-                       }
                }
 
                rx_byte_cnt += skb->len;
index 9938f7a5fc0a004dbdead758d81444e9dee8d17b..1cd4cddd5c583cf56495e2c53166e2492f174bbb 100644 (file)
@@ -104,7 +104,22 @@ struct enetc_cbdr {
 };
 
 #define ENETC_TXBD(BDR, i) (&(((union enetc_tx_bd *)((BDR).bd_base))[i]))
-#define ENETC_RXBD(BDR, i) (&(((union enetc_rx_bd *)((BDR).bd_base))[i]))
+
+static inline union enetc_rx_bd *enetc_rxbd(struct enetc_bdr *rx_ring, int i)
+{
+       return &(((union enetc_rx_bd *)rx_ring->bd_base)[i]);
+}
+
+static inline union enetc_rx_bd *enetc_rxbd_next(struct enetc_bdr *rx_ring,
+                                                union enetc_rx_bd *rxbd,
+                                                int i)
+{
+       rxbd++;
+       if (unlikely(++i == rx_ring->bd_count))
+               rxbd = rx_ring->bd_base;
+
+       return rxbd;
+}
 
 struct enetc_msg_swbd {
        void *vaddr;