[Intel-wired-lan] [PATCH v4 3/9] igc: Introduce igc_rx_buffer_flip() helper

[Andre Guedes]

The igc driver implements the same page recycling scheme from other
Intel drivers which reuses the page by flipping the buffer. The code
to handle buffer flips is duplicated in many locations so this patch
introduces the igc_rx_buffer_flip() helper and uses it where applicable.

Signed-off-by: Andre Guedes <andre.guedes at intel.com>
Reviewed-by: Maciej Fijalkowski <maciej.fijalkowski at intel.com>
---
 drivers/net/ethernet/intel/igc/igc_main.c | 42 +++++++++++------------
 1 file changed, 20 insertions(+), 22 deletions(-)

diff --git a/drivers/net/ethernet/intel/igc/igc_main.c b/drivers/net/ethernet/intel/igc/igc_main.c
index 5ce9253cca19..31dc58a82cf3 100644
--- a/drivers/net/ethernet/intel/igc/igc_main.c
+++ b/drivers/net/ethernet/intel/igc/igc_main.c
@@ -1513,6 +1513,16 @@ static struct igc_rx_buffer *igc_get_rx_buffer(struct igc_ring *rx_ring,
 	return rx_buffer;
 }
 
+static void igc_rx_buffer_flip(struct igc_rx_buffer *buffer,
+			       unsigned int truesize)
+{
+#if (PAGE_SIZE < 8192)
+	buffer->page_offset ^= truesize;
+#else
+	buffer->page_offset += truesize;
+#endif
+}
+
 /**
  * igc_add_rx_frag - Add contents of Rx buffer to sk_buff
  * @rx_ring: rx descriptor ring to transact packets on
@@ -1527,20 +1537,18 @@ static void igc_add_rx_frag(struct igc_ring *rx_ring,
 			    struct sk_buff *skb,
 			    unsigned int size)
 {
+	unsigned int truesize;
 #if (PAGE_SIZE < 8192)
-	unsigned int truesize = igc_rx_pg_size(rx_ring) / 2;
-
-	skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags, rx_buffer->page,
-			rx_buffer->page_offset, size, truesize);
-	rx_buffer->page_offset ^= truesize;
+	truesize = igc_rx_pg_size(rx_ring) / 2;
 #else
-	unsigned int truesize = ring_uses_build_skb(rx_ring) ?
-				SKB_DATA_ALIGN(IGC_SKB_PAD + size) :
-				SKB_DATA_ALIGN(size);
+	truesize = ring_uses_build_skb(rx_ring) ?
+		   SKB_DATA_ALIGN(IGC_SKB_PAD + size) :
+		   SKB_DATA_ALIGN(size);
+#endif
 	skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags, rx_buffer->page,
 			rx_buffer->page_offset, size, truesize);
-	rx_buffer->page_offset += truesize;
-#endif
+
+	igc_rx_buffer_flip(rx_buffer, truesize);
 }
 
 static struct sk_buff *igc_build_skb(struct igc_ring *rx_ring,
@@ -1569,13 +1577,7 @@ static struct sk_buff *igc_build_skb(struct igc_ring *rx_ring,
 	skb_reserve(skb, IGC_SKB_PAD);
 	__skb_put(skb, size);
 
-	/* update buffer offset */
-#if (PAGE_SIZE < 8192)
-	rx_buffer->page_offset ^= truesize;
-#else
-	rx_buffer->page_offset += truesize;
-#endif
-
+	igc_rx_buffer_flip(rx_buffer, truesize);
 	return skb;
 }
 
@@ -1621,11 +1623,7 @@ static struct sk_buff *igc_construct_skb(struct igc_ring *rx_ring,
 		skb_add_rx_frag(skb, 0, rx_buffer->page,
 				(va + headlen) - page_address(rx_buffer->page),
 				size, truesize);
-#if (PAGE_SIZE < 8192)
-		rx_buffer->page_offset ^= truesize;
-#else
-		rx_buffer->page_offset += truesize;
-#endif
+		igc_rx_buffer_flip(rx_buffer, truesize);
 	} else {
 		rx_buffer->pagecnt_bias++;
 	}
-- 
2.28.0