ena: Link IRQs to NAPI instances

Link IRQs to NAPI instances with netif_napi_set_irq. This information
can be queried with the netdev-genl API. Note that the ENA device
appears to allocate an IRQ for management purposes which does not have a
NAPI associated with it; this commit takes this into consideration to
accurately construct a map between IRQs and NAPI instances.

Compare the output of /proc/interrupts for my ena device with the output of
netdev-genl after applying this patch:

$ cat /proc/interrupts | grep enp55s0 | cut -f1 --delimiter=':'
 94
 95
 96
 97
 98
 99
100
101

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

[{'id': 8208, 'ifindex': 2, 'irq': 101},
 {'id': 8207, 'ifindex': 2, 'irq': 100},
 {'id': 8206, 'ifindex': 2, 'irq': 99},
 {'id': 8205, 'ifindex': 2, 'irq': 98},
 {'id': 8204, 'ifindex': 2, 'irq': 97},
 {'id': 8203, 'ifindex': 2, 'irq': 96},
 {'id': 8202, 'ifindex': 2, 'irq': 95},
 {'id': 8201, 'ifindex': 2, 'irq': 94}]

Signed-off-by: Joe Damato <jdamato@fastly.com>
Reviewed-by: David Arinzon <darinzon@amazon.com>
Link: https://patch.msgid.link/20241002001331.65444-2-jdamato@fastly.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/drivers/net/ethernet/amazon/ena/ena_netdev.c b/drivers/net/ethernet/amazon/ena/ena_netdev.c
index c5b50cfa935a386a4507ef1fbd67e4beddd81b86..74ce9fa45cf87400ac7b71ee93a34d343137976a 100644 (file)
--- a/drivers/net/ethernet/amazon/ena/ena_netdev.c
+++ b/drivers/net/ethernet/amazon/ena/ena_netdev.c
@@ -1677,9 +1677,9 @@ static int ena_request_mgmnt_irq(struct ena_adapter *adapter)
 static int ena_request_io_irq(struct ena_adapter *adapter)
 {
        u32 io_queue_count = adapter->num_io_queues + adapter->xdp_num_queues;
+       int rc = 0, i, k, irq_idx;
        unsigned long flags = 0;
        struct ena_irq *irq;
-       int rc = 0, i, k;
 
        if (!test_bit(ENA_FLAG_MSIX_ENABLED, &adapter->flags)) {
                netif_err(adapter, ifup, adapter->netdev,
@@ -1705,6 +1705,16 @@ static int ena_request_io_irq(struct ena_adapter *adapter)
                irq_set_affinity_hint(irq->vector, &irq->affinity_hint_mask);
        }
 
+       /* Now that IO IRQs have been successfully allocated map them to the
+        * corresponding IO NAPI instance. Note that the mgmnt IRQ does not
+        * have a NAPI, so care must be taken to correctly map IRQs to NAPIs.
+        */
+       for (i = 0; i < io_queue_count; i++) {
+               irq_idx = ENA_IO_IRQ_IDX(i);
+               irq = &adapter->irq_tbl[irq_idx];
+               netif_napi_set_irq(&adapter->ena_napi[i].napi, irq->vector);
+       }
+
        return rc;
 
 err: