Link queues to NAPI instances via netdev-genl API so that users can
query this information with netlink. Handle a few cases in the driver:
1. Link/unlink the NAPIs when XDP is enabled/disabled
2. Handle IGC_FLAG_QUEUE_PAIRS enabled and disabled
Example output when IGC_FLAG_QUEUE_PAIRS is enabled:
$ ./tools/net/ynl/cli.py --spec Documentation/netlink/specs/netdev.yaml \
--dump queue-get --json='{"ifindex": 2}'
[{'id': 0, 'ifindex': 2, 'napi-id': 8193, 'type': 'rx'},
{'id': 1, 'ifindex': 2, 'napi-id': 8194, 'type': 'rx'},
{'id': 2, 'ifindex': 2, 'napi-id': 8195, 'type': 'rx'},
{'id': 3, 'ifindex': 2, 'napi-id': 8196, 'type': 'rx'},
{'id': 0, 'ifindex': 2, 'napi-id': 8193, 'type': 'tx'},
{'id': 1, 'ifindex': 2, 'napi-id': 8194, 'type': 'tx'},
{'id': 2, 'ifindex': 2, 'napi-id': 8195, 'type': 'tx'},
{'id': 3, 'ifindex': 2, 'napi-id': 8196, 'type': 'tx'}]
Since IGC_FLAG_QUEUE_PAIRS is enabled, you'll note that the same NAPI ID
is present for both rx and tx queues at the same index, for example
index 0:
{'id': 0, 'ifindex': 2, 'napi-id': 8193, 'type': 'rx'},
{'id': 0, 'ifindex': 2, 'napi-id': 8193, 'type': 'tx'},
To test IGC_FLAG_QUEUE_PAIRS disabled, a test system was booted using
the grub command line option "maxcpus=2" to force
igc_set_interrupt_capability to disable IGC_FLAG_QUEUE_PAIRS.
Example output when IGC_FLAG_QUEUE_PAIRS is disabled:
$ lscpu | grep "On-line CPU"
On-line CPU(s) list: 0,2
$ ethtool -l enp86s0 | tail -5
Current hardware settings:
RX: n/a
TX: n/a
Other: 1
Combined: 2
$ cat /proc/interrupts | grep enp
144: [...] enp86s0
145: [...] enp86s0-rx-0
146: [...] enp86s0-rx-1
147: [...] enp86s0-tx-0
148: [...] enp86s0-tx-1
1 "other" IRQ, and 2 IRQs for each of RX and Tx, so we expect netlink to
report 4 IRQs with unique NAPI IDs:
$ ./tools/net/ynl/cli.py --spec Documentation/netlink/specs/netdev.yaml \
--dump napi-get --json='{"ifindex": 2}'
[{'id': 8196, 'ifindex': 2, 'irq': 148},
{'id': 8195, 'ifindex': 2, 'irq': 147},
{'id': 8194, 'ifindex': 2, 'irq': 146},
{'id': 8193, 'ifindex': 2, 'irq': 145}]
Now we examine which queues these NAPIs are associated with, expecting
that since IGC_FLAG_QUEUE_PAIRS is disabled each RX and TX queue will
have its own NAPI instance:
$ ./tools/net/ynl/cli.py --spec Documentation/netlink/specs/netdev.yaml \
--dump queue-get --json='{"ifindex": 2}'
[{'id': 0, 'ifindex': 2, 'napi-id': 8193, 'type': 'rx'},
{'id': 1, 'ifindex': 2, 'napi-id': 8194, 'type': 'rx'},
{'id': 0, 'ifindex': 2, 'napi-id': 8195, 'type': 'tx'},
{'id': 1, 'ifindex': 2, 'napi-id': 8196, 'type': 'tx'}]
Signed-off-by: Joe Damato <jdam...@fastly.com>
