[PATCH net-next v2 8/8] selftests: net: test listing NAPI vs queue resets

[Jakub Kicinski <kuba@kernel.org>]

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>
---
 tools/testing/selftests/net/nl_netdev.py | 19 ++++++++++++++++++-
 1 file changed, 18 insertions(+), 1 deletion(-)

diff --git a/tools/testing/selftests/net/nl_netdev.py b/tools/testing/selftests/net/nl_netdev.py
index 93d9d914529b..93e8cb671c3d 100755
--- a/tools/testing/selftests/net/nl_netdev.py
+++ b/tools/testing/selftests/net/nl_netdev.py
@@ -18,6 +18,23 @@ from lib.py import NetdevFamily, NetdevSimDev, ip
     ksft_eq(len(lo_info['xdp-rx-metadata-features']), 0)
 
 
+def napi_list_check(nf) -> None:
+    with NetdevSimDev(queue_count=100) as nsimdev:
+        nsim = nsimdev.nsims[0]
+
+        ip(f"link set dev {nsim.ifname} up")
+
+        napis = nf.napi_get({'ifindex': nsim.ifindex}, dump=True)
+        ksft_eq(len(napis), 100)
+
+        for q in [50, 0, 99]:
+            for i in range(4):
+                nsim.dfs_write("queue_reset", f"{q} {i}")
+                napis = nf.napi_get({'ifindex': nsim.ifindex}, dump=True)
+                ksft_eq(len(napis), 100,
+                        comment=f"queue count after reset queue {q} mode {i}")
+
+
 def page_pool_check(nf) -> None:
     with NetdevSimDev() as nsimdev:
         nsim = nsimdev.nsims[0]
@@ -89,7 +106,7 @@ from lib.py import NetdevFamily, NetdevSimDev, ip
 
 def main() -> None:
     nf = NetdevFamily()
-    ksft_run([empty_check, lo_check, page_pool_check],
+    ksft_run([empty_check, lo_check, page_pool_check, napi_list_check],
              args=(nf, ))
     ksft_exit()
 
-- 
2.47.1