[dpdk-dev] [PATCH v3] net/i40e: fix Rx packet statistics

[Alvin Zhang <alvinx.zhang@intel.com>]

Some packets are discarded by the NIC because they are larger than
the MTU, these packets should be counted as "RX error" instead of
"RX packet", for example:

  pkt1 = Ether()/IP()/Raw('x' * 1400)
  pkt2 = Ether()/IP()/Raw('x' * 1500)

  ---------------- Forward statistics for port 0 -----------------
  RX-packets: 2 RX-dropped: 0 RX-total: 2
  TX-packets: 1 TX-dropped: 0 TX-total: 1
  ----------------------------------------------------------------

  Here the packet pkt2 has been discarded, but still was counted
  by "RX-packets"

The register 'GL_RXERR1' can count above discarded packets.
This patch adds reading and calculation of the 'GL_RXERR1' counter
when reporting DPDK statistics.

Fixes: f4a91c38b4ad ("i40e: add extended stats")
Cc: stable@dpdk.org

Signed-off-by: Alvin Zhang <alvinx.zhang@intel.com>
---

v3: update code notes according to comment.
---
 drivers/net/i40e/i40e_ethdev.c | 16 +++++++++++++---
 drivers/net/i40e/i40e_ethdev.h | 10 ++++++++++
 2 files changed, 23 insertions(+), 3 deletions(-)

diff --git a/drivers/net/i40e/i40e_ethdev.c b/drivers/net/i40e/i40e_ethdev.c
index 7a2a828..7a207b2 100644
--- a/drivers/net/i40e/i40e_ethdev.c
+++ b/drivers/net/i40e/i40e_ethdev.c
@@ -532,7 +532,7 @@ static int i40e_sw_tunnel_filter_insert(struct i40e_pf *pf,
 /* store statistics names and its offset in stats structure */
 struct rte_i40e_xstats_name_off {
 	char name[RTE_ETH_XSTATS_NAME_SIZE];
-	unsigned offset;
+	int offset;
 };
 
 static const struct rte_i40e_xstats_name_off rte_i40e_stats_strings[] = {
@@ -542,6 +542,8 @@ struct rte_i40e_xstats_name_off {
 	{"rx_dropped_packets", offsetof(struct i40e_eth_stats, rx_discards)},
 	{"rx_unknown_protocol_packets", offsetof(struct i40e_eth_stats,
 		rx_unknown_protocol)},
+	{"rx_size_error_packets", offsetof(struct i40e_pf, rx_err1) -
+				  offsetof(struct i40e_pf, stats)},
 	{"tx_unicast_packets", offsetof(struct i40e_eth_stats, tx_unicast)},
 	{"tx_multicast_packets", offsetof(struct i40e_eth_stats, tx_multicast)},
 	{"tx_broadcast_packets", offsetof(struct i40e_eth_stats, tx_broadcast)},
@@ -3238,6 +3240,10 @@ void i40e_flex_payload_reg_set_default(struct i40e_hw *hw)
 			    pf->offset_loaded,
 			    &os->eth.rx_unknown_protocol,
 			    &ns->eth.rx_unknown_protocol);
+	i40e_stat_update_48(hw, I40E_GL_RXERR1_H(hw->pf_id + I40E_MAX_VF),
+			    I40E_GL_RXERR1_L(hw->pf_id + I40E_MAX_VF),
+			    pf->offset_loaded, &pf->rx_err1_offset,
+			    &pf->rx_err1);
 	i40e_stat_update_48_in_64(hw, I40E_GLPRT_GOTCH(hw->port),
 				  I40E_GLPRT_GOTCL(hw->port),
 				  pf->offset_loaded, &os->eth.tx_bytes,
@@ -3437,7 +3443,8 @@ void i40e_flex_payload_reg_set_default(struct i40e_hw *hw)
 	stats->ipackets = pf->main_vsi->eth_stats.rx_unicast +
 			pf->main_vsi->eth_stats.rx_multicast +
 			pf->main_vsi->eth_stats.rx_broadcast -
-			pf->main_vsi->eth_stats.rx_discards;
+			pf->main_vsi->eth_stats.rx_discards -
+			pf->rx_err1;
 	stats->opackets = ns->eth.tx_unicast +
 			ns->eth.tx_multicast +
 			ns->eth.tx_broadcast;
@@ -3451,7 +3458,8 @@ void i40e_flex_payload_reg_set_default(struct i40e_hw *hw)
 			pf->main_vsi->eth_stats.rx_discards;
 	stats->ierrors  = ns->crc_errors +
 			ns->rx_length_errors + ns->rx_undersize +
-			ns->rx_oversize + ns->rx_fragments + ns->rx_jabber;
+			ns->rx_oversize + ns->rx_fragments + ns->rx_jabber +
+			pf->rx_err1;
 
 	if (pf->vfs) {
 		for (i = 0; i < pf->vf_num; i++) {
@@ -6232,6 +6240,8 @@ struct i40e_vsi *
 	memset(&pf->stats_offset, 0, sizeof(struct i40e_hw_port_stats));
 	memset(&pf->internal_stats, 0, sizeof(struct i40e_eth_stats));
 	memset(&pf->internal_stats_offset, 0, sizeof(struct i40e_eth_stats));
+	pf->rx_err1 = 0;
+	pf->rx_err1_offset = 0;
 
 	ret = i40e_pf_get_switch_config(pf);
 	if (ret != I40E_SUCCESS) {
diff --git a/drivers/net/i40e/i40e_ethdev.h b/drivers/net/i40e/i40e_ethdev.h
index cd6deab..8e14d9a 100644
--- a/drivers/net/i40e/i40e_ethdev.h
+++ b/drivers/net/i40e/i40e_ethdev.h
@@ -19,6 +19,13 @@
 #include "base/i40e_type.h"
 #include "base/virtchnl.h"
 
+/**
+ * _i=0...143,
+ * counters 0-127 are for the 128 VFs,
+ * counters 128-143 are for the 16 PFs
+ */
+#define I40E_GL_RXERR1_H(_i)	(0x00318004 + ((_i) * 8))
+
 #define I40E_VLAN_TAG_SIZE        4
 
 #define I40E_AQ_LEN               32
@@ -1134,6 +1141,9 @@ struct i40e_pf {
 
 	struct i40e_hw_port_stats stats_offset;
 	struct i40e_hw_port_stats stats;
+	u64 rx_err1;	/* rxerr1 */
+	u64 rx_err1_offset;
+
 	/* internal packet statistics, it should be excluded from the total */
 	struct i40e_eth_stats internal_stats_offset;
 	struct i40e_eth_stats internal_stats;
-- 
1.8.3.1