diff mbox series

[net-next,v2,1/2] selftests: net-drv: exercise queue stats when the device is down

Message ID 20240730223932.3432862-1-sdf@fomichev.me (mailing list archive)
State New
Headers show
Series [net-next,v2,1/2] selftests: net-drv: exercise queue stats when the device is down | expand

Commit Message

Stanislav Fomichev July 30, 2024, 10:39 p.m. UTC
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

v2:
- KTAP output formatting (Jakub)
- defer instead of try/finally (Jakub)
- disappearing stats is an error (Jakub)
- ksft_ge instead of open coding (Jakub)

Signed-off-by: Stanislav Fomichev <sdf@fomichev.me>
--
Cc: Shuah Khan <shuah@kernel.org>
Cc: Joe Damato <jdamato@fastly.com>
Cc: Petr Machata <petrm@nvidia.com>
Cc: linux-kselftest@vger.kernel.org
---
 tools/testing/selftests/drivers/net/stats.py | 25 +++++++++++++++++++-
 1 file changed, 24 insertions(+), 1 deletion(-)

Comments

Petr Machata July 31, 2024, 11:34 a.m. UTC | #1
Stanislav Fomichev <sdf@fomichev.me> writes:

> 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
>
> v2:
> - KTAP output formatting (Jakub)
> - defer instead of try/finally (Jakub)
> - disappearing stats is an error (Jakub)
> - ksft_ge instead of open coding (Jakub)
>
> Signed-off-by: Stanislav Fomichev <sdf@fomichev.me>
> --
> Cc: Shuah Khan <shuah@kernel.org>
> Cc: Joe Damato <jdamato@fastly.com>
> Cc: Petr Machata <petrm@nvidia.com>
> Cc: linux-kselftest@vger.kernel.org
> ---
>  tools/testing/selftests/drivers/net/stats.py | 25 +++++++++++++++++++-
>  1 file changed, 24 insertions(+), 1 deletion(-)
>
> diff --git a/tools/testing/selftests/drivers/net/stats.py b/tools/testing/selftests/drivers/net/stats.py
> index 820b8e0a22c6..93f9204f51c4 100755
> --- a/tools/testing/selftests/drivers/net/stats.py
> +++ b/tools/testing/selftests/drivers/net/stats.py
> @@ -5,6 +5,7 @@ from lib.py import ksft_run, ksft_exit, ksft_pr
>  from lib.py import ksft_ge, ksft_eq, ksft_in, ksft_true, ksft_raises, KsftSkipEx, KsftXfailEx
>  from lib.py import EthtoolFamily, NetdevFamily, RtnlFamily, NlError
>  from lib.py import NetDrvEnv
> +from lib.py import ip, defer
>  
>  ethnl = EthtoolFamily()
>  netfam = NetdevFamily()
> @@ -133,9 +134,31 @@ rtnl = RtnlFamily()
>      ksft_eq(cm.exception.nl_msg.extack['bad-attr'], '.ifindex')
>  
>  
> +def check_down(cfg) -> None:
> +    try:
> +        qstat = netfam.qstats_get({"ifindex": cfg.ifindex}, dump=True)
> +    except NlError as e:
> +        if e.error == 95:

Could you do this as if e.error == errno.ENOTSUP?

> +            raise KsftSkipEx("qstats not supported by the device")
> +        raise
> +
> +    ip(f"link set dev {cfg.dev['ifname']} down")
> +    defer(ip, f"link set dev {cfg.dev['ifname']} up")
> +
> +    qstat = qstat[0]

Consider moving the [0] inside the try to make the two qstats_get
statements obviously the same.

> +    qstat2 = netfam.qstats_get({"ifindex": cfg.ifindex}, dump=True)[0]
> +    for k, v in qstat.items():
> +        ksft_ge(qstat2[k], qstat[k], comment=f"{k} went backwards on device down")
> +
> +    # 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)
> +
> +
>  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()
Jakub Kicinski Aug. 1, 2024, 12:32 a.m. UTC | #2
On Wed, 31 Jul 2024 13:34:58 +0200 Petr Machata wrote:
> > +        qstat = netfam.qstats_get({"ifindex": cfg.ifindex}, dump=True)
> > +    except NlError as e:
> > +        if e.error == 95:  
> 
> Could you do this as if e.error == errno.ENOTSUP?

just to be clear EOPNOTSUPP ..
Stanislav Fomichev Aug. 1, 2024, 1:23 a.m. UTC | #3
On 07/31, Jakub Kicinski wrote:
> On Wed, 31 Jul 2024 13:34:58 +0200 Petr Machata wrote:
> > > +        qstat = netfam.qstats_get({"ifindex": cfg.ifindex}, dump=True)
> > > +    except NlError as e:
> > > +        if e.error == 95:  
> > 
> > Could you do this as if e.error == errno.ENOTSUP?
> 
> just to be clear EOPNOTSUPP ..

That might be the reason it's coded explicitly as 95? :-D
Petr Machata Aug. 1, 2024, 8:50 a.m. UTC | #4
Stanislav Fomichev <sdf@fomichev.me> writes:

> On 07/31, Jakub Kicinski wrote:
>> On Wed, 31 Jul 2024 13:34:58 +0200 Petr Machata wrote:
>> > > +        qstat = netfam.qstats_get({"ifindex": cfg.ifindex}, dump=True)
>> > > +    except NlError as e:
>> > > +        if e.error == 95:  
>> > 
>> > Could you do this as if e.error == errno.ENOTSUP?
>> 
>> just to be clear EOPNOTSUPP ..
>
> That might be the reason it's coded explicitly as 95? :-D

Both exist, I just didn't notice the latter.

>>> import errno
>>> errno.ENOTSUP
95
>>> errno.EOPNOTSUPP
95
Stanislav Fomichev Aug. 1, 2024, 3:34 p.m. UTC | #5
On 08/01, Petr Machata wrote:
> 
> Stanislav Fomichev <sdf@fomichev.me> writes:
> 
> > On 07/31, Jakub Kicinski wrote:
> >> On Wed, 31 Jul 2024 13:34:58 +0200 Petr Machata wrote:
> >> > > +        qstat = netfam.qstats_get({"ifindex": cfg.ifindex}, dump=True)
> >> > > +    except NlError as e:
> >> > > +        if e.error == 95:  
> >> > 
> >> > Could you do this as if e.error == errno.ENOTSUP?
> >> 
> >> just to be clear EOPNOTSUPP ..
> >
> > That might be the reason it's coded explicitly as 95? :-D
> 
> Both exist, I just didn't notice the latter.
> 
> >>> import errno
> >>> errno.ENOTSUP
> 95
> >>> errno.EOPNOTSUPP
> 95

I believe Jakub was talking about kernel's ENOTSUPP (524) vs EOPNOTSUPP (95):

$ grep ENOTSUPP include/linux/errno.h
#define ENOTSUPP        524     /* Operation is not supported */

$ grep EOPNOTSUPP include/uapi/asm-generic/errno.h
#define EOPNOTSUPP      95      /* Operation not supported on transport endpoint */

These two are frequently confused.

OTOH, ENOTSUP looks like a userspace/libc invention:

$ grep -w ENOTSUP /usr/include/bits/errno.h
# ifndef ENOTSUP
#  define ENOTSUP               EOPNOTSUPP

I'm gonna stick to kernel's EOPNOTSUPP to make it look similar to what
we have on the kernel side.
Petr Machata Aug. 1, 2024, 9:38 p.m. UTC | #6
Stanislav Fomichev <sdf@fomichev.me> writes:

> On 08/01, Petr Machata wrote:
>> 
>> Stanislav Fomichev <sdf@fomichev.me> writes:
>> 
>> > On 07/31, Jakub Kicinski wrote:
>> >> On Wed, 31 Jul 2024 13:34:58 +0200 Petr Machata wrote:
>> >> > > +        qstat = netfam.qstats_get({"ifindex": cfg.ifindex}, dump=True)
>> >> > > +    except NlError as e:
>> >> > > +        if e.error == 95:  
>> >> > 
>> >> > Could you do this as if e.error == errno.ENOTSUP?
>> >> 
>> >> just to be clear EOPNOTSUPP ..
>> >
>> > That might be the reason it's coded explicitly as 95? :-D
>> 
>> Both exist, I just didn't notice the latter.
>> 
>> >>> import errno
>> >>> errno.ENOTSUP
>> 95
>> >>> errno.EOPNOTSUPP
>> 95
>
> I believe Jakub was talking about kernel's ENOTSUPP (524) vs EOPNOTSUPP (95):
>
> $ grep ENOTSUPP include/linux/errno.h
> #define ENOTSUPP        524     /* Operation is not supported */
>
> $ grep EOPNOTSUPP include/uapi/asm-generic/errno.h
> #define EOPNOTSUPP      95      /* Operation not supported on transport endpoint */
>
> These two are frequently confused.
>
> OTOH, ENOTSUP looks like a userspace/libc invention:
>
> $ grep -w ENOTSUP /usr/include/bits/errno.h
> # ifndef ENOTSUP
> #  define ENOTSUP               EOPNOTSUPP
>
> I'm gonna stick to kernel's EOPNOTSUPP to make it look similar to what
> we have on the kernel side.

Yep, sounds good.
diff mbox series

Patch

diff --git a/tools/testing/selftests/drivers/net/stats.py b/tools/testing/selftests/drivers/net/stats.py
index 820b8e0a22c6..93f9204f51c4 100755
--- a/tools/testing/selftests/drivers/net/stats.py
+++ b/tools/testing/selftests/drivers/net/stats.py
@@ -5,6 +5,7 @@  from lib.py import ksft_run, ksft_exit, ksft_pr
 from lib.py import ksft_ge, ksft_eq, ksft_in, ksft_true, ksft_raises, KsftSkipEx, KsftXfailEx
 from lib.py import EthtoolFamily, NetdevFamily, RtnlFamily, NlError
 from lib.py import NetDrvEnv
+from lib.py import ip, defer
 
 ethnl = EthtoolFamily()
 netfam = NetdevFamily()
@@ -133,9 +134,31 @@  rtnl = RtnlFamily()
     ksft_eq(cm.exception.nl_msg.extack['bad-attr'], '.ifindex')
 
 
+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")
+    defer(ip, f"link set dev {cfg.dev['ifname']} up")
+
+    qstat = qstat[0]
+    qstat2 = netfam.qstats_get({"ifindex": cfg.ifindex}, dump=True)[0]
+    for k, v in qstat.items():
+        ksft_ge(qstat2[k], qstat[k], comment=f"{k} went backwards on device down")
+
+    # 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)
+
+
 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()