Commit Graph

8 Commits

Author SHA1 Message Date
Samiullah Khawaja
8e7583a4f6 net: define an enum for the napi threaded state
Instead of using '0' and '1' for napi threaded state use an enum with
'disabled' and 'enabled' states.

Tested:
 ./tools/testing/selftests/net/nl_netdev.py
 TAP version 13
 1..7
 ok 1 nl_netdev.empty_check
 ok 2 nl_netdev.lo_check
 ok 3 nl_netdev.page_pool_check
 ok 4 nl_netdev.napi_list_check
 ok 5 nl_netdev.dev_set_threaded
 ok 6 nl_netdev.napi_set_threaded
 ok 7 nl_netdev.nsim_rxq_reset_down
 # Totals: pass:7 fail:0 xfail:0 xpass:0 skip:0 error:0

Signed-off-by: Samiullah Khawaja <skhawaja@google.com>
Link: https://patch.msgid.link/20250723013031.2911384-4-skhawaja@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-07-24 18:34:55 -07:00
Samiullah Khawaja
2677010e77 Add support to set NAPI threaded for individual NAPI
A net device has a threaded sysctl that can be used to enable threaded
NAPI polling on all of the NAPI contexts under that device. Allow
enabling threaded NAPI polling at individual NAPI level using netlink.

Extend the netlink operation `napi-set` and allow setting the threaded
attribute of a NAPI. This will enable the threaded polling on a NAPI
context.

Add a test in `nl_netdev.py` that verifies various cases of threaded
NAPI being set at NAPI and at device level.

Tested
 ./tools/testing/selftests/net/nl_netdev.py
 TAP version 13
 1..7
 ok 1 nl_netdev.empty_check
 ok 2 nl_netdev.lo_check
 ok 3 nl_netdev.page_pool_check
 ok 4 nl_netdev.napi_list_check
 ok 5 nl_netdev.dev_set_threaded
 ok 6 nl_netdev.napi_set_threaded
 ok 7 nl_netdev.nsim_rxq_reset_down
 # Totals: pass:7 fail:0 xfail:0 xpass:0 skip:0 error:0

Signed-off-by: Samiullah Khawaja <skhawaja@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20250710211203.3979655-1-skhawaja@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-07-14 18:02:37 -07:00
Samiullah Khawaja
689883de94 net: stop napi kthreads when THREADED napi is disabled
Once the THREADED napi is disabled, the napi kthread should also be
stopped. Keeping the kthread intact after disabling THREADED napi makes
the PID of this kthread show up in the output of netlink 'napi-get' and
ps -ef output.

The is discussed in the patch below:
https://lore.kernel.org/all/20250502191548.559cc416@kernel.org

NAPI kthread should stop only if,

- There are no pending napi poll scheduled for this thread.
- There are no new napi poll scheduled for this thread while it has
  stopped.
- The ____napi_schedule can correctly fallback to the softirq for napi
  polling.

Since napi_schedule_prep provides mutual exclusion over STATE_SCHED bit,
it is safe to unset the STATE_THREADED when SCHED_THREADED is set or the
SCHED bit is not set. SCHED_THREADED being set means that SCHED is
already set and the kthread owns this napi.

To disable threaded napi, unset STATE_THREADED bit safely if
SCHED_THREADED is set or SCHED is unset. Once STATE_THREADED is unset
safely then wait for the kthread to unset the SCHED_THREADED bit so it
safe to stop the kthread.

Add a new test in nl_netdev to verify this behaviour.

Tested:
 ./tools/testing/selftests/net/nl_netdev.py
 TAP version 13
 1..6
 ok 1 nl_netdev.empty_check
 ok 2 nl_netdev.lo_check
 ok 3 nl_netdev.page_pool_check
 ok 4 nl_netdev.napi_list_check
 ok 5 nl_netdev.dev_set_threaded
 ok 6 nl_netdev.nsim_rxq_reset_down
 # Totals: pass:6 fail:0 xfail:0 xpass:0 skip:0 error:0

Ran neper for 300 seconds and did enable/disable of thread napi in a
loop continuously.

Signed-off-by: Samiullah Khawaja <skhawaja@google.com>
Link: https://patch.msgid.link/20250609173015.3851695-1-skhawaja@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-06-10 17:52:03 -07:00
Jakub Kicinski
285b3f78ea netdevsim: allow normal queue reset while down
Resetting queues while the device is down should be legal.
Allow it, test it. Ideally we'd test this with a real device
supporting devmem but I don't have access to such devices.

Reviewed-by: Mina Almasry <almasrymina@google.com>
Link: https://patch.msgid.link/20250206225638.1387810-5-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-02-07 17:21:03 -08:00
Jakub Kicinski
eb721f117e selftests: net: test listing NAPI vs queue resets
Test listing netdevsim NAPIs before and after a single queue
has been reset (and NAPIs re-added).

Start from resetting the middle queue because edge cases
(first / last) may actually be less likely to trigger bugs.

  # ./tools/testing/selftests/net/nl_netdev.py
  KTAP version 1
  1..4
  ok 1 nl_netdev.empty_check
  ok 2 nl_netdev.lo_check
  ok 3 nl_netdev.page_pool_check
  ok 4 nl_netdev.napi_list_check
  # Totals: pass:4 fail:0 xfail:0 xpass:0 skip:0 error:0

Reviewed-by: Willem de Bruijn <willemb@google.com>
Acked-by: Stanislav Fomichev <sdf@fomichev.me>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2025-01-09 15:33:09 +01:00
Jakub Kicinski
4fa6bd4b33 selftests: net: set the exit code correctly in Python tests
Test cases need to exit with non-zero status if they failed,
we currently don't do that:

  # KTAP version 1
  # 1..3
  # # At /root/ksft-net-drv/drivers/net/./ping.py line 18:
  # # Check failed 1 != 2
  # not ok 1 ping.test_v4
  # ok 2 ping.test_v6
  # ok 3 ping.test_tcp
  # # Totals: pass:2 fail:1 xfail:0 xpass:0 skip:0 error:0
  ok 1 selftests: drivers/net: ping.py
  ^^^^

It's a bit tempting to make the exit part of ksft_run(),
but that only works well for very trivial setups. We can
revisit this later, if people forget to call ksft_exit().

Link: https://lore.kernel.org/r/20240417231146.2435572-3-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-04-18 16:15:31 -07:00
Jakub Kicinski
05fa5c31b9 selftests: net: exercise page pool reporting via netlink
Add a Python test for the basic ops.

  # ./net/nl_netdev.py
  KTAP version 1
  1..3
  ok 1 nl_netdev.empty_check
  ok 2 nl_netdev.lo_check
  ok 3 nl_netdev.page_pool_check
  # Totals: pass:3 fail:0 xfail:0 xpass:0 skip:0 error:0

Reviewed-by: Petr Machata <petrm@nvidia.com>
Link: https://lore.kernel.org/r/20240412141436.828666-7-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-04-15 11:21:13 -07:00
Jakub Kicinski
796c8c7fd2 selftests: nl_netdev: add a trivial Netlink netdev test
Add a trivial test using YNL.

  $ ./tools/testing/selftests/net/nl_netdev.py
  KTAP version 1
  1..2
  ok 1 nl_netdev.empty_check
  ok 2 nl_netdev.lo_check

Instantiate the family once, it takes longer than the test itself.

Reviewed-by: Petr Machata <petrm@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2024-04-08 11:40:41 +01:00