Re: [PATCH net 5/5] selftests: net-drv: stats: sanity check netlink dumps

[Petr Machata <petrm@nvidia.com>]

Jakub Kicinski <kuba@kernel.org> writes:

> Sanity check netlink dumps, to make sure dumps don't have
> repeated entries or gaps in IDs.
>
> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
> ---
> CC: shuah@kernel.org
> CC: linux-kselftest@vger.kernel.org
> ---
>  tools/testing/selftests/drivers/net/stats.py | 19 ++++++++++++++++++-
>  1 file changed, 18 insertions(+), 1 deletion(-)
>
> diff --git a/tools/testing/selftests/drivers/net/stats.py b/tools/testing/selftests/drivers/net/stats.py
> index 63e3c045a3b2..031ac9def6c0 100755
> --- a/tools/testing/selftests/drivers/net/stats.py
> +++ b/tools/testing/selftests/drivers/net/stats.py
> @@ -110,6 +110,23 @@ rtnl = RtnlFamily()
>              ksft_ge(triple[1][key], triple[0][key], comment="bad key: " + key)
>              ksft_ge(triple[2][key], triple[1][key], comment="bad key: " + key)
>  
> +    # Sanity check the dumps
> +    queues = NetdevFamily(recv_size=4096).qstats_get({"scope": "queue"}, dump=True)
> +    # Reformat the output into {ifindex: {rx: [id, id, ...], tx: [id, id, ...]}}
> +    parsed = {}
> +    for entry in queues:
> +        ifindex = entry["ifindex"]
> +        if ifindex not in parsed:
> +            parsed[ifindex] = {"rx":[], "tx": []}
> +        parsed[ifindex][entry["queue-type"]].append(entry['queue-id'])

BTW setdefault() exists for exactly these add-unless-already-exists
scenarios:

        parsed_entry = parsed.setdefault(ifindex, {"rx":[], "tx": []})
        parsed_entry[entry["queue-type"]].append(entry['queue-id'])

Sometimes this can be used to inline the whole expression, such as
mydict.setdefault(key, []).append(value), but that would be unwieldy here.

Anyway, consider rewriting, but it's a nit, it's readable just fine as is.

Reviewed-by: Petr Machata <petrm@nvidia.com>

> +    # Now, validate
> +    for ifindex, queues in parsed.items():
> +        for qtype in ['rx', 'tx']:
> +            ksft_eq(len(queues[qtype]), len(set(queues[qtype])),
> +                    comment="repeated queue keys")
> +            ksft_eq(len(queues[qtype]), max(queues[qtype]) + 1,
> +                    comment="missing queue keys")
> +
>      # Test invalid dumps
>      # 0 is invalid
>      with ksft_raises(NlError) as cm:
> @@ -158,7 +175,7 @@ rtnl = RtnlFamily()
>  
>  
>  def main() -> None:
> -    with NetDrvEnv(__file__) as cfg:
> +    with NetDrvEnv(__file__, queue_count=100) as cfg:
>          ksft_run([check_pause, check_fec, pkt_byte_sum, qstat_by_ifindex,
>                    check_down],
>                   args=(cfg, ))