net: enetc: move skb creation into enetc_build_skb

We need to build an skb from two code paths now: from the plain RX data
path and from the XDP data path when the verdict is XDP_PASS.

Create a new enetc_build_skb function which contains the essential steps
for building an skb based on the first and last positions of buffer
descriptors within the RX ring.

We also squash the enetc_process_skb function into enetc_build_skb,
because what that function did wasn't very meaningful on its own.

The "rx_frm_cnt++" instruction has been moved around napi_gro_receive
for cosmetic reasons, to be in the same spot as rx_byte_cnt++, which
itself must be before napi_gro_receive, because that's when we lose
ownership of the skb.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/freescale/enetc/enetc.c b/drivers/net/ethernet/freescale/enetc/enetc.c
index 362cfba..b2071b8 100644 (file)
--- a/drivers/net/ethernet/freescale/enetc/enetc.c
+++ b/drivers/net/ethernet/freescale/enetc/enetc.c
@@ -513,13 +513,6 @@ static void enetc_get_offloads(struct enetc_bdr *rx_ring,
 #endif
 }
 
-static void enetc_process_skb(struct enetc_bdr *rx_ring,
-                             struct sk_buff *skb)
-{
-       skb_record_rx_queue(skb, rx_ring->index);
-       skb->protocol = eth_type_trans(skb, rx_ring->ndev);
-}
-
 static bool enetc_page_reusable(struct page *page)
 {
        return (!page_is_pfmemalloc(page) && page_ref_count(page) == 1);
@@ -627,6 +620,47 @@ static bool enetc_check_bd_errors_and_consume(struct enetc_bdr *rx_ring,
        return true;
 }
 
+static struct sk_buff *enetc_build_skb(struct enetc_bdr *rx_ring,
+                                      u32 bd_status, union enetc_rx_bd **rxbd,
+                                      int *i, int *cleaned_cnt)
+{
+       struct sk_buff *skb;
+       u16 size;
+
+       size = le16_to_cpu((*rxbd)->r.buf_len);
+       skb = enetc_map_rx_buff_to_skb(rx_ring, *i, size);
+       if (!skb)
+               return NULL;
+
+       enetc_get_offloads(rx_ring, *rxbd, skb);
+
+       (*cleaned_cnt)++;
+
+       enetc_rxbd_next(rx_ring, rxbd, i);
+
+       /* not last BD in frame? */
+       while (!(bd_status & ENETC_RXBD_LSTATUS_F)) {
+               bd_status = le32_to_cpu((*rxbd)->r.lstatus);
+               size = ENETC_RXB_DMA_SIZE;
+
+               if (bd_status & ENETC_RXBD_LSTATUS_F) {
+                       dma_rmb();
+                       size = le16_to_cpu((*rxbd)->r.buf_len);
+               }
+
+               enetc_add_rx_buff_to_skb(rx_ring, *i, size, skb);
+
+               (*cleaned_cnt)++;
+
+               enetc_rxbd_next(rx_ring, rxbd, i);
+       }
+
+       skb_record_rx_queue(skb, rx_ring->index);
+       skb->protocol = eth_type_trans(skb, rx_ring->ndev);
+
+       return skb;
+}
+
 #define ENETC_RXBD_BUNDLE 16 /* # of BDs to update at once */
 
 static int enetc_clean_rx_ring(struct enetc_bdr *rx_ring,
@@ -643,7 +677,6 @@ static int enetc_clean_rx_ring(struct enetc_bdr *rx_ring,
                union enetc_rx_bd *rxbd;
                struct sk_buff *skb;
                u32 bd_status;
-               u16 size;
 
                if (cleaned_cnt >= ENETC_RXBD_BUNDLE)
                        cleaned_cnt -= enetc_refill_rx_ring(rx_ring,
@@ -661,41 +694,15 @@ static int enetc_clean_rx_ring(struct enetc_bdr *rx_ring,
                                                      &rxbd, &i))
                        break;
 
-               size = le16_to_cpu(rxbd->r.buf_len);
-               skb = enetc_map_rx_buff_to_skb(rx_ring, i, size);
+               skb = enetc_build_skb(rx_ring, bd_status, &rxbd, &i,
+                                     &cleaned_cnt);
                if (!skb)
                        break;
 
-               enetc_get_offloads(rx_ring, rxbd, skb);
-
-               cleaned_cnt++;
-
-               enetc_rxbd_next(rx_ring, &rxbd, &i);
-
-               /* not last BD in frame? */
-               while (!(bd_status & ENETC_RXBD_LSTATUS_F)) {
-                       bd_status = le32_to_cpu(rxbd->r.lstatus);
-                       size = ENETC_RXB_DMA_SIZE;
-
-                       if (bd_status & ENETC_RXBD_LSTATUS_F) {
-                               dma_rmb();
-                               size = le16_to_cpu(rxbd->r.buf_len);
-                       }
-
-                       enetc_add_rx_buff_to_skb(rx_ring, i, size, skb);
-
-                       cleaned_cnt++;
-
-                       enetc_rxbd_next(rx_ring, &rxbd, &i);
-               }
-
                rx_byte_cnt += skb->len;
-
-               enetc_process_skb(rx_ring, skb);
+               rx_frm_cnt++;
 
                napi_gro_receive(napi, skb);
-
-               rx_frm_cnt++;
        }
 
        rx_ring->next_to_clean = i;