[Intel-wired-lan] [net-next v3 1/2] e1000e: Link NAPI instances to queues and IRQs

[Joe Damato <jdamato@fastly.com>]

Add support for netdev-genl, allowing users to query IRQ, NAPI, and queue
information.

After this patch is applied, note the IRQs assigned to my NIC:

$ cat /proc/interrupts | grep ens | cut -f1 --delimiter=':'
 50
 51
 52

While e1000e allocates 3 IRQs (RX, TX, and other), it looks like e1000e
only has a single NAPI, so I've associated the NAPI with the RX IRQ (50
on my system, seen above).

Note the output from the cli:

$ ./tools/net/ynl/cli.py --spec Documentation/netlink/specs/netdev.yaml \
                       --dump napi-get --json='{"ifindex": 2}'
[{'id': 145, 'ifindex': 2, 'irq': 50}]

This device supports only 1 rx and 1 tx queue. so querying that:

$ ./tools/net/ynl/cli.py --spec Documentation/netlink/specs/netdev.yaml \
                       --dump queue-get --json='{"ifindex": 2}'
[{'id': 0, 'ifindex': 2, 'napi-id': 145, 'type': 'rx'},
 {'id': 0, 'ifindex': 2, 'napi-id': 145, 'type': 'tx'}]

Signed-off-by: Joe Damato <jdamato@fastly.com>
---
 drivers/net/ethernet/intel/e1000e/netdev.c | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/drivers/net/ethernet/intel/e1000e/netdev.c b/drivers/net/ethernet/intel/e1000e/netdev.c
index f103249b12fa..b527642c3a82 100644
--- a/drivers/net/ethernet/intel/e1000e/netdev.c
+++ b/drivers/net/ethernet/intel/e1000e/netdev.c
@@ -4613,6 +4613,7 @@ int e1000e_open(struct net_device *netdev)
 	struct e1000_hw *hw = &adapter->hw;
 	struct pci_dev *pdev = adapter->pdev;
 	int err;
+	int irq;
 
 	/* disallow open during test */
 	if (test_bit(__E1000_TESTING, &adapter->state))
@@ -4676,7 +4677,15 @@ int e1000e_open(struct net_device *netdev)
 	/* From here on the code is the same as e1000e_up() */
 	clear_bit(__E1000_DOWN, &adapter->state);
 
+	if (adapter->int_mode == E1000E_INT_MODE_MSIX)
+		irq = adapter->msix_entries[0].vector;
+	else
+		irq = adapter->pdev->irq;
+
+	netif_napi_set_irq(&adapter->napi, irq);
 	napi_enable(&adapter->napi);
+	netif_queue_set_napi(netdev, 0, NETDEV_QUEUE_TYPE_RX, &adapter->napi);
+	netif_queue_set_napi(netdev, 0, NETDEV_QUEUE_TYPE_TX, &adapter->napi);
 
 	e1000_irq_enable(adapter);
 
@@ -4735,6 +4744,8 @@ int e1000e_close(struct net_device *netdev)
 		netdev_info(netdev, "NIC Link is Down\n");
 	}
 
+	netif_queue_set_napi(netdev, 0, NETDEV_QUEUE_TYPE_RX, NULL);
+	netif_queue_set_napi(netdev, 0, NETDEV_QUEUE_TYPE_TX, NULL);
 	napi_disable(&adapter->napi);
 
 	e1000e_free_tx_resources(adapter->tx_ring);
-- 
2.34.1