bnx2x: use netdev_alloc_frag()

Using netdev_alloc_frag() instead of kmalloc() permits better GRO or
TCP coalescing behavior, as skb_gro_receive() doesn't have to fallback
to frag_list overhead.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Dmitry Kravkov <dmitry@broadcom.com>
Cc: Eilon Greenstein <eilong@broadcom.com>
Acked-by: Dmitry Kravkov <dmitry@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 32 insertions, 13 deletions

diff --git a/drivers/net/ethernet/broadcom/bnx2x/bnx2x.h b/drivers/net/ethernet/broadcom/bnx2x/bnx2x.h
index 9a3b81e75c01..e8d4db10c8f3 100644
--- a/drivers/net/ethernet/broadcom/bnx2x/bnx2x.h
+++ b/drivers/net/ethernet/broadcom/bnx2x/bnx2x.h
@@ -489,7 +489,7 @@ struct bnx2x_fastpath {
         u32                     ustorm_rx_prods_offset;
 
         u32                     rx_buf_size;
-
+        u32                     rx_frag_size; /* 0 if kmalloced(), or rx_buf_size + NET_SKB_PAD */
         dma_addr_t              status_blk_mapping;
 
         enum bnx2x_tpa_mode_t   mode;
diff --git a/drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.c b/drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.c
index 67baddd13a6e..a2998bea5d4b 100644
--- a/drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.c
+++ b/drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.c
@@ -552,6 +552,23 @@ static int bnx2x_fill_frag_skb(struct bnx2x *bp, struct bnx2x_fastpath *fp,
         return 0;
 }
 
+static void bnx2x_frag_free(const struct bnx2x_fastpath *fp, void *data)
+{
+        if (fp->rx_frag_size)
+                put_page(virt_to_head_page(data));
+        else
+                kfree(data);
+}
+
+static void *bnx2x_frag_alloc(const struct bnx2x_fastpath *fp)
+{
+        if (fp->rx_frag_size)
+                return netdev_alloc_frag(fp->rx_frag_size);
+
+        return kmalloc(fp->rx_buf_size + NET_SKB_PAD, GFP_ATOMIC);
+}
+
+
 static void bnx2x_tpa_stop(struct bnx2x *bp, struct bnx2x_fastpath *fp,
                            struct bnx2x_agg_info *tpa_info,
                            u16 pages,
@@ -574,15 +591,14 @@ static void bnx2x_tpa_stop(struct bnx2x *bp, struct bnx2x_fastpath *fp,
                 goto drop;
 
         /* Try to allocate the new data */
-        new_data = kmalloc(fp->rx_buf_size + NET_SKB_PAD, GFP_ATOMIC);
-
+        new_data = bnx2x_frag_alloc(fp);
         /* Unmap skb in the pool anyway, as we are going to change
            pool entry status to BNX2X_TPA_STOP even if new skb allocation
            fails. */
         dma_unmap_single(&bp->pdev->dev, dma_unmap_addr(rx_buf, mapping),
                          fp->rx_buf_size, DMA_FROM_DEVICE);
         if (likely(new_data))
-                skb = build_skb(data, 0);
+                skb = build_skb(data, fp->rx_frag_size);
 
         if (likely(skb)) {
 #ifdef BNX2X_STOP_ON_ERROR
@@ -619,7 +635,7 @@ static void bnx2x_tpa_stop(struct bnx2x *bp, struct bnx2x_fastpath *fp,
 
                 return;
         }
-        kfree(new_data);
+        bnx2x_frag_free(fp, new_data);
 drop:
         /* drop the packet and keep the buffer in the bin */
         DP(NETIF_MSG_RX_STATUS,
@@ -635,7 +651,7 @@ static int bnx2x_alloc_rx_data(struct bnx2x *bp,
         struct eth_rx_bd *rx_bd = &fp->rx_desc_ring[index];
         dma_addr_t mapping;
 
-        data = kmalloc(fp->rx_buf_size + NET_SKB_PAD, GFP_ATOMIC);
+        data = bnx2x_frag_alloc(fp);
         if (unlikely(data == NULL))
                 return -ENOMEM;
 
@@ -643,7 +659,7 @@ static int bnx2x_alloc_rx_data(struct bnx2x *bp,
                                  fp->rx_buf_size,
                                  DMA_FROM_DEVICE);
         if (unlikely(dma_mapping_error(&bp->pdev->dev, mapping))) {
-                kfree(data);
+                bnx2x_frag_free(fp, data);
                 BNX2X_ERR("Can't map rx data\n");
                 return -ENOMEM;
         }
@@ -845,9 +861,9 @@ int bnx2x_rx_int(struct bnx2x_fastpath *fp, int budget)
                                                  dma_unmap_addr(rx_buf, mapping),
                                                  fp->rx_buf_size,
                                                  DMA_FROM_DEVICE);
-                                skb = build_skb(data, 0);
+                                skb = build_skb(data, fp->rx_frag_size);
                                 if (unlikely(!skb)) {
-                                        kfree(data);
+                                        bnx2x_frag_free(fp, data);
                                         bnx2x_fp_qstats(bp, fp)->
                                                         rx_skb_alloc_failed++;
                                         goto next_rx;
@@ -1145,7 +1161,7 @@ static void bnx2x_free_tpa_pool(struct bnx2x *bp,
                         dma_unmap_single(&bp->pdev->dev,
                                          dma_unmap_addr(first_buf, mapping),
                                          fp->rx_buf_size, DMA_FROM_DEVICE);
-                kfree(data);
+                bnx2x_frag_free(fp, data);
                 first_buf->data = NULL;
         }
 }
@@ -1190,8 +1206,7 @@ void bnx2x_init_rx_rings(struct bnx2x *bp)
                                 struct sw_rx_bd *first_buf =
                                         &tpa_info->first_buf;
 
-                                first_buf->data = kmalloc(fp->rx_buf_size + NET_SKB_PAD,
-                                                          GFP_ATOMIC);
+                                first_buf->data = bnx2x_frag_alloc(fp);
                                 if (!first_buf->data) {
                                         BNX2X_ERR("Failed to allocate TPA skb pool for queue[%d] - disabling TPA on this queue!\n",
                                                   j);
@@ -1323,7 +1338,7 @@ static void bnx2x_free_rx_bds(struct bnx2x_fastpath *fp)
                                  fp->rx_buf_size, DMA_FROM_DEVICE);
 
                 rx_buf->data = NULL;
-                kfree(data);
+                bnx2x_frag_free(fp, data);
         }
 }
 
@@ -1782,6 +1797,10 @@ static void bnx2x_set_rx_buf_size(struct bnx2x *bp)
                                   mtu +
                                   BNX2X_FW_RX_ALIGN_END;
                 /* Note : rx_buf_size doesnt take into account NET_SKB_PAD */
+                if (fp->rx_buf_size + NET_SKB_PAD <= PAGE_SIZE)
+                        fp->rx_frag_size = fp->rx_buf_size + NET_SKB_PAD;
+                else
+                        fp->rx_frag_size = 0;
         }
 }