ixgbe: Improve statistics accuracy for DDP traffic

Noticed that the byte and packet count statistics are under-
counting traffic handled by the DDP offload when there is more
than one DDP completion processed in a single call to
ixgbe_clean_rx_irq. This patch fixes that.

I tried to optimize the setting of the rss value so that it
only would have to be computed once, and only when there is
a DDP completion present.

Signed-off-by: Mark Rustad <mark.d.rustad@intel.com>
Tested-by: Phil Schmitt <phillip.j.schmitt@intel.com>
Tested-by: Ross Brattain <ross.b.brattain@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
index b3b846b32deb0838521599628102dd3a6bcfb3ea..2dc9d91e2b679c1082622eef8de017a85f190b3f 100644 (file)
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
@@ -1785,7 +1785,8 @@ static bool ixgbe_clean_rx_irq(struct ixgbe_q_vector *q_vector,
        unsigned int total_rx_bytes = 0, total_rx_packets = 0;
 #ifdef IXGBE_FCOE
        struct ixgbe_adapter *adapter = q_vector->adapter;
-       int ddp_bytes = 0;
+       int ddp_bytes;
+       unsigned int mss = 0;
 #endif /* IXGBE_FCOE */
        u16 cleaned_count = ixgbe_desc_unused(rx_ring);
 
@@ -1839,6 +1840,20 @@ static bool ixgbe_clean_rx_irq(struct ixgbe_q_vector *q_vector,
                /* if ddp, not passing to ULD unless for FCP_RSP or error */
                if (ixgbe_rx_is_fcoe(rx_ring, rx_desc)) {
                        ddp_bytes = ixgbe_fcoe_ddp(adapter, rx_desc, skb);
+                       /* include DDPed FCoE data */
+                       if (ddp_bytes > 0) {
+                               if (!mss) {
+                                       mss = rx_ring->netdev->mtu -
+                                               sizeof(struct fcoe_hdr) -
+                                               sizeof(struct fc_frame_header) -
+                                               sizeof(struct fcoe_crc_eof);
+                                       if (mss > 512)
+                                               mss &= ~511;
+                               }
+                               total_rx_bytes += ddp_bytes;
+                               total_rx_packets += DIV_ROUND_UP(ddp_bytes,
+                                                                mss);
+                       }
                        if (!ddp_bytes) {
                                dev_kfree_skb_any(skb);
                                continue;
@@ -1852,21 +1867,6 @@ static bool ixgbe_clean_rx_irq(struct ixgbe_q_vector *q_vector,
                budget--;
        } while (likely(budget));
 
-#ifdef IXGBE_FCOE
-       /* include DDPed FCoE data */
-       if (ddp_bytes > 0) {
-               unsigned int mss;
-
-               mss = rx_ring->netdev->mtu - sizeof(struct fcoe_hdr) -
-                       sizeof(struct fc_frame_header) -
-                       sizeof(struct fcoe_crc_eof);
-               if (mss > 512)
-                       mss &= ~511;
-               total_rx_bytes += ddp_bytes;
-               total_rx_packets += DIV_ROUND_UP(ddp_bytes, mss);
-       }
-
-#endif /* IXGBE_FCOE */
        u64_stats_update_begin(&rx_ring->syncp);
        rx_ring->stats.packets += total_rx_packets;
        rx_ring->stats.bytes += total_rx_bytes;