On Mon, 29 Jul 2024 15:10:41 -0700 Stanislav Fomichev wrote:
> Verify that total device stats don't decrease after it has been turned down.
> Also make sure the device doesn't crash when we access per-queue stats
> when it's down (in case it tries to access some pointers that are NULL).
>
> KTAP version 1
> 1..5
> ok 1 stats.check_pause
> ok 2 stats.check_fec
> ok 3 stats.pkt_byte_sum
> ok 4 stats.qstat_by_ifindex
> ok 5 stats.check_down
> \# Totals: pass:5 fail:0 xfail:0 xpass:0 skip:0 error:0
nit: may be personal preference but if you indent by 2 spaces
that will neutralize the # as well
> +def check_down(cfg) -> None:
> + try:
> + qstat = netfam.qstats_get({"ifindex": cfg.ifindex}, dump=True)
> + except NlError as e:
> + if e.error == 95:
> + raise KsftSkipEx("qstats not supported by the device")
> + raise
> +
> + ip(f"link set dev {cfg.dev['ifname']} down")
> +
> + try:
The rest of this test predates defer() but I think it may be cleaner:
ip(f"link set dev {cfg.dev['ifname']} down")
defer(ip, f"link set dev {cfg.dev['ifname']} up")
then you don't need to try/finally.
> + qstat = qstat[0]
> + qstat2 = netfam.qstats_get({"ifindex": cfg.ifindex}, dump=True)[0]
> + for k, v in qstat.items():
> + if k not in qstat2:
> + # skip the stats that are not globally preserved
> + continue
I think we should fail if stats disappear. I can't think of a legit
reason for that to happen.
> + if qstat2[k] < qstat[k]:
> + raise Exception(f"{k} ({qstat2[k]}) should be preserved but has lower value ({qstat[k]}) when the device is down")
ksft_ge(qstat2[k], qstat[k], comment=k)
?
> +
> + # exercise per-queue API to make sure that "device down" state
> + # is handled correctly and doesn't crash
> + netfam.qstats_get({"ifindex": cfg.ifindex, "scope": "queue"}, dump=True)
> + finally:
> + ip(f"link set dev {cfg.dev['ifname']} up")
> +
> +
> def main() -> None:
> with NetDrvEnv(__file__) as cfg:
> - ksft_run([check_pause, check_fec, pkt_byte_sum, qstat_by_ifindex],
> + ksft_run([check_pause, check_fec, pkt_byte_sum, qstat_by_ifindex,
> + check_down],
> args=(cfg, ))
> ksft_exit()
>
