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, 156 insertions, 2 deletions

diff --git a/drivers/net/ethernet/google/gve/gve_main.c b/drivers/net/ethernet/google/gve/gve_main.c
index 0fc68f844edf..936ff4c9d250 100644
--- a/drivers/net/ethernet/google/gve/gve_main.c
+++ b/drivers/net/ethernet/google/gve/gve_main.c
@@ -78,6 +78,66 @@ static void gve_free_counter_array(struct gve_priv *priv)
 	priv->counter_array = NULL;
 }
 
+/* NIC requests to report stats */
+static void gve_stats_report_task(struct work_struct *work)
+{
+	struct gve_priv *priv = container_of(work, struct gve_priv,
+					     stats_report_task);
+	if (gve_get_do_report_stats(priv)) {
+		gve_handle_report_stats(priv);
+		gve_clear_do_report_stats(priv);
+	}
+}
+
+static void gve_stats_report_schedule(struct gve_priv *priv)
+{
+	if (!gve_get_probe_in_progress(priv) &&
+	    !gve_get_reset_in_progress(priv)) {
+		gve_set_do_report_stats(priv);
+		queue_work(priv->gve_wq, &priv->stats_report_task);
+	}
+}
+
+static void gve_stats_report_timer(struct timer_list *t)
+{
+	struct gve_priv *priv = from_timer(priv, t, stats_report_timer);
+
+	mod_timer(&priv->stats_report_timer,
+		  round_jiffies(jiffies +
+		  msecs_to_jiffies(priv->stats_report_timer_period)));
+	gve_stats_report_schedule(priv);
+}
+
+static int gve_alloc_stats_report(struct gve_priv *priv)
+{
+	int tx_stats_num, rx_stats_num;
+
+	tx_stats_num = (GVE_TX_STATS_REPORT_NUM) *
+		       priv->tx_cfg.num_queues;
+	rx_stats_num = (GVE_RX_STATS_REPORT_NUM) *
+		       priv->rx_cfg.num_queues;
+	priv->stats_report_len = sizeof(struct gve_stats_report) +
+				 (tx_stats_num + rx_stats_num) *
+				 sizeof(struct stats);
+	priv->stats_report =
+		dma_alloc_coherent(&priv->pdev->dev, priv->stats_report_len,
+				   &priv->stats_report_bus, GFP_KERNEL);
+	if (!priv->stats_report)
+		return -ENOMEM;
+	/* Set up timer for the report-stats task */
+	timer_setup(&priv->stats_report_timer, gve_stats_report_timer, 0);
+	priv->stats_report_timer_period = GVE_STATS_REPORT_TIMER_PERIOD;
+	return 0;
+}
+
+static void gve_free_stats_report(struct gve_priv *priv)
+{
+	del_timer_sync(&priv->stats_report_timer);
+	dma_free_coherent(&priv->pdev->dev, priv->stats_report_len,
+			  priv->stats_report, priv->stats_report_bus);
+	priv->stats_report = NULL;
+}
+
 static irqreturn_t gve_mgmnt_intr(int irq, void *arg)
 {
 	struct gve_priv *priv = arg;
@@ -270,6 +330,9 @@ static int gve_setup_device_resources(struct gve_priv *priv)
 	err = gve_alloc_notify_blocks(priv);
 	if (err)
 		goto abort_with_counter;
+	err = gve_alloc_stats_report(priv);
+	if (err)
+		goto abort_with_ntfy_blocks;
 	err = gve_adminq_configure_device_resources(priv,
 						    priv->counter_array_bus,
 						    priv->num_event_counters,
@@ -279,10 +342,18 @@ static int gve_setup_device_resources(struct gve_priv *priv)
 		dev_err(&priv->pdev->dev,
 			"could not setup device_resources: err=%d\n", err);
 		err = -ENXIO;
-		goto abort_with_ntfy_blocks;
+		goto abort_with_stats_report;
 	}
+	err = gve_adminq_report_stats(priv, priv->stats_report_len,
+				      priv->stats_report_bus,
+				      GVE_STATS_REPORT_TIMER_PERIOD);
+	if (err)
+		dev_err(&priv->pdev->dev,
+			"Failed to report stats: err=%d\n", err);
 	gve_set_device_resources_ok(priv);
 	return 0;
+abort_with_stats_report:
+	gve_free_stats_report(priv);
 abort_with_ntfy_blocks:
 	gve_free_notify_blocks(priv);
 abort_with_counter:
@@ -298,6 +369,13 @@ static void gve_teardown_device_resources(struct gve_priv *priv)
 
 	/* Tell device its resources are being freed */
 	if (gve_get_device_resources_ok(priv)) {
+		/* detach the stats report */
+		err = gve_adminq_report_stats(priv, 0, 0x0, GVE_STATS_REPORT_TIMER_PERIOD);
+		if (err) {
+			dev_err(&priv->pdev->dev,
+				"Failed to detach stats report: err=%d\n", err);
+			gve_trigger_reset(priv);
+		}
 		err = gve_adminq_deconfigure_device_resources(priv);
 		if (err) {
 			dev_err(&priv->pdev->dev,
@@ -308,6 +386,7 @@ static void gve_teardown_device_resources(struct gve_priv *priv)
 	}
 	gve_free_counter_array(priv);
 	gve_free_notify_blocks(priv);
+	gve_free_stats_report(priv);
 	gve_clear_device_resources_ok(priv);
 }
 
@@ -699,6 +778,11 @@ static int gve_open(struct net_device *dev)
 		goto reset;
 	gve_set_device_rings_ok(priv);
 
+	if (gve_get_report_stats(priv))
+		mod_timer(&priv->stats_report_timer,
+			  round_jiffies(jiffies +
+				msecs_to_jiffies(priv->stats_report_timer_period)));
+
 	gve_turnup(priv);
 	netif_carrier_on(dev);
 	priv->interface_up_cnt++;
@@ -740,6 +824,7 @@ static int gve_close(struct net_device *dev)
 			goto err;
 		gve_clear_device_rings_ok(priv);
 	}
+	del_timer_sync(&priv->stats_report_timer);
 
 	gve_free_rings(priv);
 	gve_free_qpls(priv);
@@ -823,6 +908,7 @@ static void gve_turndown(struct gve_priv *priv)
 	netif_tx_disable(priv->dev);
 
 	gve_clear_napi_enabled(priv);
+	gve_clear_report_stats(priv);
 }
 
 static void gve_turnup(struct gve_priv *priv)
@@ -873,6 +959,10 @@ static void gve_handle_status(struct gve_priv *priv, u32 status)
 		dev_info(&priv->pdev->dev, "Device requested reset.\n");
 		gve_set_do_reset(priv);
 	}
+	if (GVE_DEVICE_STATUS_REPORT_STATS_MASK & status) {
+		priv->stats_report_trigger_cnt++;
+		gve_set_do_report_stats(priv);
+	}
 }
 
 static void gve_handle_reset(struct gve_priv *priv)
@@ -891,7 +981,68 @@ static void gve_handle_reset(struct gve_priv *priv)
 	}
 }
 
-/* Handle NIC status register changes and reset requests */
+void gve_handle_report_stats(struct gve_priv *priv)
+{
+	int idx, stats_idx = 0, tx_bytes;
+	unsigned int start = 0;
+	struct stats *stats = priv->stats_report->stats;
+
+	if (!gve_get_report_stats(priv))
+		return;
+
+	be64_add_cpu(&priv->stats_report->written_count, 1);
+	/* tx stats */
+	if (priv->tx) {
+		for (idx = 0; idx < priv->tx_cfg.num_queues; idx++) {
+			do {
+				start = u64_stats_fetch_begin(&priv->tx[idx].statss);
+				tx_bytes = priv->tx[idx].bytes_done;
+			} while (u64_stats_fetch_retry(&priv->tx[idx].statss, start));
+			stats[stats_idx++] = (struct stats) {
+				.stat_name = cpu_to_be32(TX_WAKE_CNT),
+				.value = cpu_to_be64(priv->tx[idx].wake_queue),
+				.queue_id = cpu_to_be32(idx),
+			};
+			stats[stats_idx++] = (struct stats) {
+				.stat_name = cpu_to_be32(TX_STOP_CNT),
+				.value = cpu_to_be64(priv->tx[idx].stop_queue),
+				.queue_id = cpu_to_be32(idx),
+			};
+			stats[stats_idx++] = (struct stats) {
+				.stat_name = cpu_to_be32(TX_FRAMES_SENT),
+				.value = cpu_to_be64(priv->tx[idx].req),
+				.queue_id = cpu_to_be32(idx),
+			};
+			stats[stats_idx++] = (struct stats) {
+				.stat_name = cpu_to_be32(TX_BYTES_SENT),
+				.value = cpu_to_be64(tx_bytes),
+				.queue_id = cpu_to_be32(idx),
+			};
+			stats[stats_idx++] = (struct stats) {
+				.stat_name = cpu_to_be32(TX_LAST_COMPLETION_PROCESSED),
+				.value = cpu_to_be64(priv->tx[idx].done),
+				.queue_id = cpu_to_be32(idx),
+			};
+		}
+	}
+	/* rx stats */
+	if (priv->rx) {
+		for (idx = 0; idx < priv->rx_cfg.num_queues; idx++) {
+			stats[stats_idx++] = (struct stats) {
+				.stat_name = cpu_to_be32(RX_NEXT_EXPECTED_SEQUENCE),
+				.value = cpu_to_be64(priv->rx[idx].desc.seqno),
+				.queue_id = cpu_to_be32(idx),
+			};
+			stats[stats_idx++] = (struct stats) {
+				.stat_name = cpu_to_be32(RX_BUFFERS_POSTED),
+				.value = cpu_to_be64(priv->rx[0].fill_cnt),
+				.queue_id = cpu_to_be32(idx),
+			};
+		}
+	}
+}
+
+/* Handle NIC status register changes, reset requests and report stats */
 static void gve_service_task(struct work_struct *work)
 {
 	struct gve_priv *priv = container_of(work, struct gve_priv,
@@ -1056,6 +1207,7 @@ int gve_reset(struct gve_priv *priv, bool attempt_teardown)
 	priv->reset_cnt++;
 	priv->interface_up_cnt = 0;
 	priv->interface_down_cnt = 0;
+	priv->stats_report_trigger_cnt = 0;
 	return err;
 }
 
@@ -1158,6 +1310,7 @@ static int gve_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 	priv->db_bar2 = db_bar;
 	priv->service_task_flags = 0x0;
 	priv->state_flags = 0x0;
+	priv->ethtool_flags = 0x0;
 
 	gve_set_probe_in_progress(priv);
 	priv->gve_wq = alloc_ordered_workqueue("gve", 0);
@@ -1167,6 +1320,7 @@ static int gve_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 		goto abort_with_netdev;
 	}
 	INIT_WORK(&priv->service_task, gve_service_task);
+	INIT_WORK(&priv->stats_report_task, gve_stats_report_task);
 	priv->tx_cfg.max_queues = max_tx_queues;
 	priv->rx_cfg.max_queues = max_rx_queues;