linux.git/net/core/netdev-genl.c, branch v6.12

netdev: add dmabuf introspection

2024-09-12T03:44:32+00:00

Add dmabuf information to page_pool stats:

$ ./cli.py --spec ../netlink/specs/netdev.yaml --dump page-pool-get
...
 {'dmabuf': 10,
  'id': 456,
  'ifindex': 3,
  'inflight': 1023,
  'inflight-mem': 4190208},
 {'dmabuf': 10,
  'id': 455,
  'ifindex': 3,
  'inflight': 1023,
  'inflight-mem': 4190208},
 {'dmabuf': 10,
  'id': 454,
  'ifindex': 3,
  'inflight': 1023,
  'inflight-mem': 4190208},
 {'dmabuf': 10,
  'id': 453,
  'ifindex': 3,
  'inflight': 1023,
  'inflight-mem': 4190208},
 {'dmabuf': 10,
  'id': 452,
  'ifindex': 3,
  'inflight': 1023,
  'inflight-mem': 4190208},
 {'dmabuf': 10,
  'id': 451,
  'ifindex': 3,
  'inflight': 1023,
  'inflight-mem': 4190208},
 {'dmabuf': 10,
  'id': 450,
  'ifindex': 3,
  'inflight': 1023,
  'inflight-mem': 4190208},
 {'dmabuf': 10,
  'id': 449,
  'ifindex': 3,
  'inflight': 1023,
  'inflight-mem': 4190208},

And queue stats:

$ ./cli.py --spec ../netlink/specs/netdev.yaml --dump queue-get
...
{'dmabuf': 10, 'id': 8, 'ifindex': 3, 'type': 'rx'},
{'dmabuf': 10, 'id': 9, 'ifindex': 3, 'type': 'rx'},
{'dmabuf': 10, 'id': 10, 'ifindex': 3, 'type': 'rx'},
{'dmabuf': 10, 'id': 11, 'ifindex': 3, 'type': 'rx'},
{'dmabuf': 10, 'id': 12, 'ifindex': 3, 'type': 'rx'},
{'dmabuf': 10, 'id': 13, 'ifindex': 3, 'type': 'rx'},
{'dmabuf': 10, 'id': 14, 'ifindex': 3, 'type': 'rx'},
{'dmabuf': 10, 'id': 15, 'ifindex': 3, 'type': 'rx'},

Suggested-by: Jakub Kicinski 
Signed-off-by: Mina Almasry 
Reviewed-by: Jakub Kicinski 
Link: https://patch.msgid.link/20240910171458.219195-14-almasrymina@google.com
Signed-off-by: Jakub Kicinski

netdev: support binding dma-buf to netdevice

2024-09-12T03:44:31+00:00

Add a netdev_dmabuf_binding struct which represents the
dma-buf-to-netdevice binding. The netlink API will bind the dma-buf to
rx queues on the netdevice. On the binding, the dma_buf_attach
& dma_buf_map_attachment will occur. The entries in the sg_table from
mapping will be inserted into a genpool to make it ready
for allocation.

The chunks in the genpool are owned by a dmabuf_chunk_owner struct which
holds the dma-buf offset of the base of the chunk and the dma_addr of
the chunk. Both are needed to use allocations that come from this chunk.

We create a new type that represents an allocation from the genpool:
net_iov. We setup the net_iov allocation size in the
genpool to PAGE_SIZE for simplicity: to match the PAGE_SIZE normally
allocated by the page pool and given to the drivers.

The user can unbind the dmabuf from the netdevice by closing the netlink
socket that established the binding. We do this so that the binding is
automatically unbound even if the userspace process crashes.

The binding and unbinding leaves an indicator in struct netdev_rx_queue
that the given queue is bound, and the binding is actuated by resetting
the rx queue using the queue API.

The netdev_dmabuf_binding struct is refcounted, and releases its
resources only when all the refs are released.

Signed-off-by: Willem de Bruijn 
Signed-off-by: Kaiyuan Zhang 
Signed-off-by: Mina Almasry 
Reviewed-by: Pavel Begunkov  # excluding netlink
Acked-by: Daniel Vetter 
Reviewed-by: Jakub Kicinski 
Link: https://patch.msgid.link/20240910171458.219195-4-almasrymina@google.com
Signed-off-by: Jakub Kicinski

net: netdev netlink api to bind dma-buf to a net device

2024-09-12T03:44:31+00:00

API takes the dma-buf fd as input, and binds it to the netdevice. The
user can specify the rx queues to bind the dma-buf to.

Suggested-by: Stanislav Fomichev 
Signed-off-by: Mina Almasry 
Reviewed-by: Donald Hunter 
Reviewed-by: Jakub Kicinski 
Link: https://patch.msgid.link/20240910171458.219195-3-almasrymina@google.com
Signed-off-by: Jakub Kicinski

netdev-genl: Set extack and fix error on napi-get

2024-09-03T01:27:15+00:00

In commit 27f91aaf49b3 ("netdev-genl: Add netlink framework functions
for napi"), when an invalid NAPI ID is specified the return value
-EINVAL is used and no extack is set.

Change the return value to -ENOENT and set the extack.

Before this commit:

$ ./tools/net/ynl/cli.py --spec Documentation/netlink/specs/netdev.yaml \
                          --do napi-get --json='{"id": 451}'
Netlink error: Invalid argument
nl_len = 36 (20) nl_flags = 0x100 nl_type = 2
	error: -22

After this commit:

$ ./tools/net/ynl/cli.py --spec Documentation/netlink/specs/netdev.yaml \
                         --do napi-get --json='{"id": 451}'
Netlink error: No such file or directory
nl_len = 44 (28) nl_flags = 0x300 nl_type = 2
	error: -2
	extack: {'bad-attr': '.id'}

Suggested-by: Jakub Kicinski 
Signed-off-by: Joe Damato 
Link: https://patch.msgid.link/20240831121707.17562-1-jdamato@fastly.com
Signed-off-by: Jakub Kicinski

netdev-genl: fix error codes when outputting XDP features

2024-06-15T01:04:29+00:00

-EINVAL will interrupt the dump. The correct error to return
if we have more data to dump is -EMSGSIZE.

Discovered by doing:

  for i in `seq 80`; do ip link add type veth; done
  ./cli.py --dbg-small-recv 5300 --spec netdev.yaml --dump dev-get >> /dev/null
  [...]
     nl_len = 64 (48) nl_flags = 0x0 nl_type = 19
     nl_len = 20 (4) nl_flags = 0x2 nl_type = 3
  	error: -22

Fixes: d3d854fd6a1d ("netdev-genl: create a simple family for netdev stuff")
Reviewed-by: Amritha Nambiar 
Reviewed-by: Eric Dumazet 
Link: https://lore.kernel.org/r/20240613213044.3675745-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski

netdev: Add queue stats for TX stop and wake

2024-05-13T21:58:36+00:00

TX queue stop and wake are counted by some drivers.
Support reporting these via netdev-genl queue stats.

Signed-off-by: Daniel Jurgens 
Reviewed-by: Jiri Pirko 
Reviewed-by: Jason Xing 
Link: https://lore.kernel.org/r/20240510201927.1821109-2-danielj@nvidia.com
Signed-off-by: Jakub Kicinski

netdev: add queue stats

2024-04-30T08:51:33+00:00

These stats are commonly. Support reporting those via netdev-genl queue
stats.

name: rx-hw-drops
name: rx-hw-drop-overruns
name: rx-csum-unnecessary
name: rx-csum-none
name: rx-csum-bad
name: rx-hw-gro-packets
name: rx-hw-gro-bytes
name: rx-hw-gro-wire-packets
name: rx-hw-gro-wire-bytes
name: rx-hw-drop-ratelimits
name: tx-hw-drops
name: tx-hw-drop-errors
name: tx-csum-none
name: tx-needs-csum
name: tx-hw-gso-packets
name: tx-hw-gso-bytes
name: tx-hw-gso-wire-packets
name: tx-hw-gso-wire-bytes
name: tx-hw-drop-ratelimits

Signed-off-by: Xuan Zhuo 
Reviewed-by: Jakub Kicinski 
Signed-off-by: Paolo Abeni

netdev: support dumping a single netdev in qstats

2024-04-23T17:09:49+00:00

Having to filter the right ifindex in the tests is a bit tedious.
Add support for dumping qstats for a single ifindex.

Reviewed-by: David Ahern 
Reviewed-by: Eric Dumazet 
Link: https://lore.kernel.org/r/20240420023543.3300306-2-kuba@kernel.org
Signed-off-by: Jakub Kicinski

netdev: add queue stat for alloc failures

2024-03-08T05:13:26+00:00

Rx alloc failures are commonly counted by drivers.
Support reporting those via netdev-genl queue stats.

Acked-by: Stanislav Fomichev 
Reviewed-by: Amritha Nambiar 
Reviewed-by: Xuan Zhuo 
Link: https://lore.kernel.org/r/20240306195509.1502746-3-kuba@kernel.org
Signed-off-by: Jakub Kicinski

netdev: add per-queue statistics

2024-03-08T05:13:25+00:00

The ethtool-nl family does a good job exposing various protocol
related and IEEE/IETF statistics which used to get dumped under
ethtool -S, with creative names. Queue stats don't have a netlink
API, yet, and remain a lion's share of ethtool -S output for new
drivers. Not only is that bad because the names differ driver to
driver but it's also bug-prone. Intuitively drivers try to report
only the stats for active queues, but querying ethtool stats
involves multiple system calls, and the number of stats is
read separately from the stats themselves. Worse still when user
space asks for values of the stats, it doesn't inform the kernel
how big the buffer is. If number of stats increases in the meantime
kernel will overflow user buffer.

Add a netlink API for dumping queue stats. Queue information is
exposed via the netdev-genl family, so add the stats there.
Support per-queue and sum-for-device dumps. Latter will be useful
when subsequent patches add more interesting common stats than
just bytes and packets.

The API does not currently distinguish between HW and SW stats.
The expectation is that the source of the stats will either not
matter much (good packets) or be obvious (skb alloc errors).

Acked-by: Stanislav Fomichev 
Reviewed-by: Amritha Nambiar 
Reviewed-by: Xuan Zhuo 
Link: https://lore.kernel.org/r/20240306195509.1502746-2-kuba@kernel.org
Signed-off-by: Jakub Kicinski