gve: Add Gvnic stats AQ command and ethtool show/set-priv-flags.

This adds functionality to report driver stats to Hypervisor.
(Users may want to turn this feature off as a matter of privacy
so a "report-stats" flag is added as an ethtool priv option.
It is also disabled by default.)
The hypervisor would trigger a stats report in case "too many"
packets dropped; the stats would be useful in debugging stuck
queues.
A "stats_report_trigger_cnt" stat is added to count the number of times
the hypervisor attempts to trigger stats report.

A timer is also added so that when report-stats is enabled, stat are
updated once every 20 seconds.

Reviewed-by: Yangchun Fu <yangchun@google.com>
Signed-off-by: Kuo Zhao <kuozhao@google.com>
Signed-off-by: David Awogbemila <awogbemila@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 93 insertions, 20 deletions

diff --git a/drivers/net/ethernet/google/gve/gve_ethtool.c b/drivers/net/ethernet/google/gve/gve_ethtool.c
index e9bef1ff7ec3..67239faa7554 100644
--- a/drivers/net/ethernet/google/gve/gve_ethtool.c
+++ b/drivers/net/ethernet/google/gve/gve_ethtool.c
@@ -6,6 +6,7 @@
 
 #include <linux/rtnetlink.h>
 #include "gve.h"
+#include "gve_adminq.h"
 
 static void gve_get_drvinfo(struct net_device *netdev,
 			    struct ethtool_drvinfo *info)
@@ -36,7 +37,7 @@ static const char gve_gstrings_main_stats[][ETH_GSTRING_LEN] = {
 	"rx_dropped", "tx_dropped", "tx_timeouts",
 	"rx_skb_alloc_fail", "rx_buf_alloc_fail", "rx_desc_err_dropped_pkt",
 	"interface_up_cnt", "interface_down_cnt", "reset_cnt",
-	"page_alloc_fail", "dma_mapping_error",
+	"page_alloc_fail", "dma_mapping_error", "stats_report_trigger_cnt",
 };
 
 static const char gve_gstrings_rx_stats[][ETH_GSTRING_LEN] = {
@@ -56,12 +57,18 @@ static const char gve_gstrings_adminq_stats[][ETH_GSTRING_LEN] = {
 	"adminq_create_tx_queue_cnt", "adminq_create_rx_queue_cnt",
 	"adminq_destroy_tx_queue_cnt", "adminq_destroy_rx_queue_cnt",
 	"adminq_dcfg_device_resources_cnt", "adminq_set_driver_parameter_cnt",
+	"adminq_report_stats_cnt",
+};
+
+static const char gve_gstrings_priv_flags[][ETH_GSTRING_LEN] = {
+	"report-stats",
 };
 
 #define GVE_MAIN_STATS_LEN  ARRAY_SIZE(gve_gstrings_main_stats)
 #define GVE_ADMINQ_STATS_LEN  ARRAY_SIZE(gve_gstrings_adminq_stats)
 #define NUM_GVE_TX_CNTS	ARRAY_SIZE(gve_gstrings_tx_stats)
 #define NUM_GVE_RX_CNTS	ARRAY_SIZE(gve_gstrings_rx_stats)
+#define GVE_PRIV_FLAGS_STR_LEN ARRAY_SIZE(gve_gstrings_priv_flags)
 
 static void gve_get_strings(struct net_device *netdev, u32 stringset, u8 *data)
 {
@@ -69,28 +76,42 @@ static void gve_get_strings(struct net_device *netdev, u32 stringset, u8 *data)
 	char *s = (char *)data;
 	int i, j;
 
-	if (stringset != ETH_SS_STATS)
-		return;
-
-	memcpy(s, *gve_gstrings_main_stats,
-	       sizeof(gve_gstrings_main_stats));
-	s += sizeof(gve_gstrings_main_stats);
-	for (i = 0; i < priv->rx_cfg.num_queues; i++) {
-		for (j = 0; j < NUM_GVE_RX_CNTS; j++) {
-			snprintf(s, ETH_GSTRING_LEN, gve_gstrings_rx_stats[j], i);
-			s += ETH_GSTRING_LEN;
+	switch (stringset) {
+	case ETH_SS_STATS:
+		memcpy(s, *gve_gstrings_main_stats,
+		       sizeof(gve_gstrings_main_stats));
+		s += sizeof(gve_gstrings_main_stats);
+
+		for (i = 0; i < priv->rx_cfg.num_queues; i++) {
+			for (j = 0; j < NUM_GVE_RX_CNTS; j++) {
+				snprintf(s, ETH_GSTRING_LEN,
+					 gve_gstrings_rx_stats[j], i);
+				s += ETH_GSTRING_LEN;
+			}
 		}
-	}
-	for (i = 0; i < priv->tx_cfg.num_queues; i++) {
-		for (j = 0; j < NUM_GVE_TX_CNTS; j++) {
-			snprintf(s, ETH_GSTRING_LEN, gve_gstrings_tx_stats[j], i);
-			s += ETH_GSTRING_LEN;
+
+		for (i = 0; i < priv->tx_cfg.num_queues; i++) {
+			for (j = 0; j < NUM_GVE_TX_CNTS; j++) {
+				snprintf(s, ETH_GSTRING_LEN,
+					 gve_gstrings_tx_stats[j], i);
+				s += ETH_GSTRING_LEN;
+			}
 		}
-	}
 
-	memcpy(s, *gve_gstrings_adminq_stats,
-	       sizeof(gve_gstrings_adminq_stats));
-	s += sizeof(gve_gstrings_adminq_stats);
+		memcpy(s, *gve_gstrings_adminq_stats,
+		       sizeof(gve_gstrings_adminq_stats));
+		s += sizeof(gve_gstrings_adminq_stats);
+		break;
+
+	case ETH_SS_PRIV_FLAGS:
+		memcpy(s, *gve_gstrings_priv_flags,
+		       sizeof(gve_gstrings_priv_flags));
+		s += sizeof(gve_gstrings_priv_flags);
+		break;
+
+	default:
+		break;
+	}
 }
 
 static int gve_get_sset_count(struct net_device *netdev, int sset)
@@ -102,6 +123,8 @@ static int gve_get_sset_count(struct net_device *netdev, int sset)
 		return GVE_MAIN_STATS_LEN + GVE_ADMINQ_STATS_LEN +
 		       (priv->rx_cfg.num_queues * NUM_GVE_RX_CNTS) +
 		       (priv->tx_cfg.num_queues * NUM_GVE_TX_CNTS);
+	case ETH_SS_PRIV_FLAGS:
+		return GVE_PRIV_FLAGS_STR_LEN;
 	default:
 		return -EOPNOTSUPP;
 	}
@@ -182,6 +205,7 @@ gve_get_ethtool_stats(struct net_device *netdev,
 	data[i++] = priv->reset_cnt;
 	data[i++] = priv->page_alloc_fail;
 	data[i++] = priv->dma_mapping_error;
+	data[i++] = priv->stats_report_trigger_cnt;
 	i = GVE_MAIN_STATS_LEN;
 
 	/* walk RX rings */
@@ -248,6 +272,7 @@ gve_get_ethtool_stats(struct net_device *netdev,
 	data[i++] = priv->adminq_destroy_rx_queue_cnt;
 	data[i++] = priv->adminq_dcfg_device_resources_cnt;
 	data[i++] = priv->adminq_set_driver_parameter_cnt;
+	data[i++] = priv->adminq_report_stats_cnt;
 }
 
 static void gve_get_channels(struct net_device *netdev,
@@ -352,6 +377,52 @@ static int gve_set_tunable(struct net_device *netdev,
 	}
 }
 
+static u32 gve_get_priv_flags(struct net_device *netdev)
+{
+	struct gve_priv *priv = netdev_priv(netdev);
+	u32 ret_flags = 0;
+
+	/* Only 1 flag exists currently: report-stats (BIT(O)), so set that flag. */
+	if (priv->ethtool_flags & BIT(0))
+		ret_flags |= BIT(0);
+	return ret_flags;
+}
+
+static int gve_set_priv_flags(struct net_device *netdev, u32 flags)
+{
+	struct gve_priv *priv = netdev_priv(netdev);
+	u64 ori_flags, new_flags;
+
+	ori_flags = READ_ONCE(priv->ethtool_flags);
+	new_flags = ori_flags;
+
+	/* Only one priv flag exists: report-stats (BIT(0))*/
+	if (flags & BIT(0))
+		new_flags |= BIT(0);
+	else
+		new_flags &= ~(BIT(0));
+	priv->ethtool_flags = new_flags;
+	/* start report-stats timer when user turns report stats on. */
+	if (flags & BIT(0)) {
+		mod_timer(&priv->stats_report_timer,
+			  round_jiffies(jiffies +
+					msecs_to_jiffies(priv->stats_report_timer_period)));
+	}
+	/* Zero off gve stats when report-stats turned off and */
+	/* delete report stats timer. */
+	if (!(flags & BIT(0)) && (ori_flags & BIT(0))) {
+		int tx_stats_num = GVE_TX_STATS_REPORT_NUM *
+			priv->tx_cfg.num_queues;
+		int rx_stats_num = GVE_RX_STATS_REPORT_NUM *
+			priv->rx_cfg.num_queues;
+
+		memset(priv->stats_report->stats, 0, (tx_stats_num + rx_stats_num) *
+				   sizeof(struct stats));
+		del_timer_sync(&priv->stats_report_timer);
+	}
+	return 0;
+}
+
 const struct ethtool_ops gve_ethtool_ops = {
 	.get_drvinfo = gve_get_drvinfo,
 	.get_strings = gve_get_strings,
@@ -366,4 +437,6 @@ const struct ethtool_ops gve_ethtool_ops = {
 	.reset = gve_user_reset,
 	.get_tunable = gve_get_tunable,
 	.set_tunable = gve_set_tunable,
+	.get_priv_flags = gve_get_priv_flags,
+	.set_priv_flags = gve_set_priv_flags,
 };