vmxnet3: support clear hardware interface counters

Add clear hardware interface counters callback for vmxnet3 device. We take a
snap shot of the statistics in the callback. For the show hardware command,
we display the delta between the current statistics and the last snapshot.

Change-Id: Ie1389d2141f519300f427fe6ff2fdf97fd9e9378
Signed-off-by: Steven <sluong@cisco.com>

3 files changed, 60 insertions, 20 deletions

diff --git a/src/plugins/vmxnet3/format.c b/src/plugins/vmxnet3/format.c
index c1a74367436..eb213c96885 100644
--- a/src/plugins/vmxnet3/format.c
+++ b/src/plugins/vmxnet3/format.c
@@ -75,47 +75,67 @@ format_vmxnet3_device (u8 * s, va_list * args)
 
   s = format (s, "\n%UTX:", format_white_space, indent);
   s = format (s, "\n%U  TSO packets                         %llu",
-	      format_white_space, indent, q->tx.stats.tso_pkts);
+	      format_white_space, indent,
+	      q->tx.stats.tso_pkts - vd->tx_stats.tso_pkts);
   s = format (s, "\n%U  TSO bytes                           %llu",
-	      format_white_space, indent, q->tx.stats.tso_bytes);
+	      format_white_space, indent,
+	      q->tx.stats.tso_bytes - vd->tx_stats.tso_bytes);
   s = format (s, "\n%U  ucast packets                       %llu",
-	      format_white_space, indent, q->tx.stats.ucast_pkts);
+	      format_white_space, indent,
+	      q->tx.stats.ucast_pkts - vd->tx_stats.ucast_pkts);
   s = format (s, "\n%U  ucast bytes                         %llu",
-	      format_white_space, indent, q->tx.stats.ucast_bytes);
+	      format_white_space, indent,
+	      q->tx.stats.ucast_bytes - vd->tx_stats.ucast_bytes);
   s = format (s, "\n%U  mcast packets                       %llu",
-	      format_white_space, indent, q->tx.stats.mcast_pkts);
+	      format_white_space, indent,
+	      q->tx.stats.mcast_pkts - vd->tx_stats.mcast_pkts);
   s = format (s, "\n%U  mcast bytes                         %llu",
-	      format_white_space, indent, q->tx.stats.mcast_bytes);
+	      format_white_space, indent,
+	      q->tx.stats.mcast_bytes - vd->tx_stats.mcast_bytes);
   s = format (s, "\n%U  bcast packets                       %llu",
-	      format_white_space, indent, q->tx.stats.bcast_pkts);
+	      format_white_space, indent,
+	      q->tx.stats.bcast_pkts - vd->tx_stats.bcast_pkts);
   s = format (s, "\n%U  bcast bytes                         %llu",
-	      format_white_space, indent, q->tx.stats.bcast_bytes);
+	      format_white_space, indent,
+	      q->tx.stats.bcast_bytes - vd->tx_stats.bcast_bytes);
   s = format (s, "\n%U  Errors packets                      %llu",
-	      format_white_space, indent, q->tx.stats.error_pkts);
+	      format_white_space, indent,
+	      q->tx.stats.error_pkts - vd->tx_stats.error_pkts);
   s = format (s, "\n%U  Discard packets                     %llu",
-	      format_white_space, indent, q->tx.stats.discard_pkts);
+	      format_white_space, indent,
+	      q->tx.stats.discard_pkts - vd->tx_stats.discard_pkts);
 
   s = format (s, "\n%URX:", format_white_space, indent);
   s = format (s, "\n%U  LRO packets                         %llu",
-	      format_white_space, indent, q->rx.stats.lro_pkts);
+	      format_white_space, indent,
+	      q->rx.stats.lro_pkts - vd->rx_stats.lro_pkts);
   s = format (s, "\n%U  LRO bytes                           %llu",
-	      format_white_space, indent, q->rx.stats.lro_bytes);
+	      format_white_space, indent,
+	      q->rx.stats.lro_bytes - vd->rx_stats.lro_bytes);
   s = format (s, "\n%U  ucast packets                       %llu",
-	      format_white_space, indent, q->rx.stats.ucast_pkts);
+	      format_white_space, indent,
+	      q->rx.stats.ucast_pkts - vd->rx_stats.ucast_pkts);
   s = format (s, "\n%U  ucast bytes                         %llu",
-	      format_white_space, indent, q->rx.stats.ucast_bytes);
+	      format_white_space, indent,
+	      q->rx.stats.ucast_bytes - vd->rx_stats.ucast_bytes);
   s = format (s, "\n%U  mcast packets                       %llu",
-	      format_white_space, indent, q->rx.stats.mcast_pkts);
+	      format_white_space, indent,
+	      q->rx.stats.mcast_pkts - vd->rx_stats.mcast_pkts);
   s = format (s, "\n%U  mcast bytes                         %llu",
-	      format_white_space, indent, q->rx.stats.mcast_bytes);
+	      format_white_space, indent,
+	      q->rx.stats.mcast_bytes - vd->rx_stats.mcast_bytes);
   s = format (s, "\n%U  bcast packets                       %llu",
-	      format_white_space, indent, q->rx.stats.bcast_pkts);
+	      format_white_space, indent,
+	      q->rx.stats.bcast_pkts - vd->rx_stats.bcast_pkts);
   s = format (s, "\n%U  bcast bytes                         %llu",
-	      format_white_space, indent, q->rx.stats.bcast_bytes);
+	      format_white_space, indent,
+	      q->rx.stats.bcast_bytes - vd->rx_stats.bcast_bytes);
   s = format (s, "\n%U  No Bufs                             %llu",
-	      format_white_space, indent, q->rx.stats.nobuf_pkts);
+	      format_white_space, indent,
+	      q->rx.stats.nobuf_pkts - vd->rx_stats.nobuf_pkts);
   s = format (s, "\n%U  Error packets                       %llu",
-	      format_white_space, indent, q->rx.stats.error_pkts);
+	      format_white_space, indent,
+	      q->rx.stats.error_pkts - vd->rx_stats.error_pkts);
   return s;
 }
 
diff --git a/src/plugins/vmxnet3/vmxnet3.c b/src/plugins/vmxnet3/vmxnet3.c
index 08d4d5cea52..a5a62e99fe5 100644
--- a/src/plugins/vmxnet3/vmxnet3.c
+++ b/src/plugins/vmxnet3/vmxnet3.c
@@ -97,6 +97,23 @@ vmxnet3_set_interface_next_node (vnet_main_t * vnm, u32 hw_if_index,
 			node_index);
 }
 
+static void
+vmxnet3_clear_hw_interface_counters (u32 instance)
+{
+  vmxnet3_main_t *vmxm = &vmxnet3_main;
+  vmxnet3_device_t *vd = pool_elt_at_index (vmxm->devices, instance);
+  vmxnet3_queues *q = &vd->dma->queues;
+
+  /*
+   * Set the "last_cleared_stats" to the current stats, so that
+   * things appear to clear from a display perspective.
+   */
+  vmxnet3_reg_write (vd, 1, VMXNET3_REG_CMD, VMXNET3_CMD_GET_STATS);
+
+  clib_memcpy (&vd->tx_stats, &q->tx.stats, sizeof (vd->tx_stats));
+  clib_memcpy (&vd->rx_stats, &q->rx.stats, sizeof (vd->rx_stats));
+}
+
 static char *vmxnet3_tx_func_error_strings[] = {
 #define _(n,s) s,
   foreach_vmxnet3_tx_func_error
@@ -110,6 +127,7 @@ VNET_DEVICE_CLASS (vmxnet3_device_class,) =
   .format_device = format_vmxnet3_device,
   .format_device_name = format_vmxnet3_device_name,
   .admin_up_down_function = vmxnet3_interface_admin_up_down,
+  .clear_counters = vmxnet3_clear_hw_interface_counters,
   .rx_mode_change_function = vmxnet3_interface_rx_mode_change,
   .rx_redirect_to_node = vmxnet3_set_interface_next_node,
   .tx_function_n_errors = VMXNET3_TX_N_ERROR,
diff --git a/src/plugins/vmxnet3/vmxnet3.h b/src/plugins/vmxnet3/vmxnet3.h
index a3306895ec0..3a40b0de49e 100644
--- a/src/plugins/vmxnet3/vmxnet3.h
+++ b/src/plugins/vmxnet3/vmxnet3.h
@@ -488,6 +488,8 @@ typedef struct
   vmxnet3_dma *dma;
 
   u32 link_speed;
+  vmxnet3_tx_stats tx_stats;
+  vmxnet3_rx_stats rx_stats;
 } vmxnet3_device_t;
 
 typedef struct