[PATCH net 3/6] ice: use ice_update_eth_stats() for representor stats

[Tony Nguyen <anthony.l.nguyen@intel.com>]

From: Petr Oros <poros@redhat.com>

ice_repr_get_stats64() and __ice_get_ethtool_stats() call
ice_update_vsi_stats() on the VF's src_vsi. This always returns early
because ICE_VSI_DOWN is permanently set for VF VSIs - ice_up() is never
called on them since queues are managed by iavf through virtchnl.

In __ice_get_ethtool_stats() the original code called
ice_update_vsi_stats() for all VSIs including representors, iterated
over ice_gstrings_vsi_stats[] to populate the data, and then bailed out
with an early return before the per-queue ring stats section. That early
return was necessary because representor VSIs have no rings on the PF
side - the rings belong to the VF driver (iavf), so accessing per-queue
stats would be invalid.

Move the representor handling to the top of __ice_get_ethtool_stats()
and call ice_update_eth_stats() directly to read the hardware GLV_*
counters. This matches ice_get_vf_stats() which already uses
ice_update_eth_stats() for the same VF VSI in legacy mode. Apply the
same fix to ice_repr_get_stats64().

Note that ice_gstrings_vsi_stats[] contains five software ring counters
(rx_buf_failed, rx_page_failed, tx_linearize, tx_busy, tx_restart) that
are always zero for representors since the PF never processes packets on
VF rings. This is pre-existing behavior unchanged by this patch.

Fixes: 7aae80cef7ba ("ice: add port representor ethtool ops and stats")
Signed-off-by: Petr Oros <poros@redhat.com>
Reviewed-by: Aleksandr Loktionov <aleksandr.loktionov@intel.com>
Tested-by: Patryk Holda <patryk.holda@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
---
 drivers/net/ethernet/intel/ice/ice_ethtool.c | 14 +++++++++++---
 drivers/net/ethernet/intel/ice/ice_repr.c    |  3 ++-
 2 files changed, 13 insertions(+), 4 deletions(-)

diff --git a/drivers/net/ethernet/intel/ice/ice_ethtool.c b/drivers/net/ethernet/intel/ice/ice_ethtool.c
index e4e1eab05bd5..e6a20af6f63d 100644
--- a/drivers/net/ethernet/intel/ice/ice_ethtool.c
+++ b/drivers/net/ethernet/intel/ice/ice_ethtool.c
@@ -1930,6 +1930,17 @@ __ice_get_ethtool_stats(struct net_device *netdev,
 	int i = 0;
 	char *p;
 
+	if (ice_is_port_repr_netdev(netdev)) {
+		ice_update_eth_stats(vsi);
+
+		for (j = 0; j < ICE_VSI_STATS_LEN; j++) {
+			p = (char *)vsi + ice_gstrings_vsi_stats[j].stat_offset;
+			data[i++] = (ice_gstrings_vsi_stats[j].sizeof_stat ==
+				     sizeof(u64)) ? *(u64 *)p : *(u32 *)p;
+		}
+		return;
+	}
+
 	ice_update_pf_stats(pf);
 	ice_update_vsi_stats(vsi);
 
@@ -1939,9 +1950,6 @@ __ice_get_ethtool_stats(struct net_device *netdev,
 			     sizeof(u64)) ? *(u64 *)p : *(u32 *)p;
 	}
 
-	if (ice_is_port_repr_netdev(netdev))
-		return;
-
 	/* populate per queue stats */
 	rcu_read_lock();
 
diff --git a/drivers/net/ethernet/intel/ice/ice_repr.c b/drivers/net/ethernet/intel/ice/ice_repr.c
index 68cdd04dd3aa..096566c697f4 100644
--- a/drivers/net/ethernet/intel/ice/ice_repr.c
+++ b/drivers/net/ethernet/intel/ice/ice_repr.c
@@ -2,6 +2,7 @@
 /* Copyright (C) 2019-2021, Intel Corporation. */
 
 #include "ice.h"
+#include "ice_lib.h"
 #include "ice_eswitch.h"
 #include "devlink/devlink.h"
 #include "devlink/port.h"
@@ -67,7 +68,7 @@ ice_repr_get_stats64(struct net_device *netdev, struct rtnl_link_stats64 *stats)
 		return;
 	vsi = repr->src_vsi;
 
-	ice_update_vsi_stats(vsi);
+	ice_update_eth_stats(vsi);
 	eth_stats = &vsi->eth_stats;
 
 	stats->tx_packets = eth_stats->tx_unicast + eth_stats->tx_broadcast +
-- 
2.47.1