diff mbox series

[net-next,4/5] selftests: drv-net: rss_ctx: check behavior of indirection table resizing

Message ID 20240705015725.680275-5-kuba@kernel.org (mailing list archive)
State Changes Requested
Delegated to: Netdev Maintainers
Headers show
Series selftests: drv-net: rss_ctx: more tests | expand

Checks

Context Check Description
netdev/series_format success Posting correctly formatted
netdev/tree_selection success Clearly marked for net-next
netdev/ynl success Generated files up to date; no warnings/errors; no diff in generated;
netdev/fixes_present success Fixes tag not required for -next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 8 this patch: 8
netdev/build_tools success Errors and warnings before: 0 this patch: 0
netdev/cc_maintainers fail 2 maintainers not CCed: linux-kselftest@vger.kernel.org shuah@kernel.org
netdev/build_clang success Errors and warnings before: 8 this patch: 8
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 8 this patch: 8
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 58 lines checked
netdev/build_clang_rust success No Rust files in patch. Skipping build
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0
netdev/contest success net-next-2024-07-05--06-00 (tests: 695)

Commit Message

Jakub Kicinski July 5, 2024, 1:57 a.m. UTC
Some workloads may want to rehash the flows in response to an imbalance.
Most effective way to do that is changing the RSS key. Check that changing
the key does not cause link flaps or traffic disruption.

Disrupting traffic for key update is not a bug, but makes the key
update unusable for rehashing under load.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
---
 .../selftests/drivers/net/hw/rss_ctx.py       | 37 ++++++++++++++++++-
 1 file changed, 36 insertions(+), 1 deletion(-)

Comments

Willem de Bruijn July 6, 2024, 2:03 p.m. UTC | #1
Jakub Kicinski wrote:
> Some workloads may want to rehash the flows in response to an imbalance.
> Most effective way to do that is changing the RSS key. Check that changing
> the key does not cause link flaps or traffic disruption.
> 
> Disrupting traffic for key update is not a bug, but makes the key
> update unusable for rehashing under load.

This is the commit message of patch 5/5
diff mbox series

Patch

diff --git a/tools/testing/selftests/drivers/net/hw/rss_ctx.py b/tools/testing/selftests/drivers/net/hw/rss_ctx.py
index fbc234d6c395..f42807e39e0d 100755
--- a/tools/testing/selftests/drivers/net/hw/rss_ctx.py
+++ b/tools/testing/selftests/drivers/net/hw/rss_ctx.py
@@ -5,7 +5,7 @@  import datetime
 import random
 from lib.py import ksft_run, ksft_pr, ksft_exit, ksft_eq, ksft_ge, ksft_lt
 from lib.py import NetDrvEpEnv
-from lib.py import NetdevFamily
+from lib.py import EthtoolFamily, NetdevFamily
 from lib.py import KsftSkipEx
 from lib.py import rand_port
 from lib.py import ethtool, ip, defer, GenerateTraffic, CmdExitFailure
@@ -203,6 +203,39 @@  from lib.py import ethtool, ip, defer, GenerateTraffic, CmdExitFailure
         raise Exception(f"Driver didn't prevent us from deactivating a used queue (context {ctx_id})")
 
 
+def test_rss_resize(cfg):
+    """Test resizing of the RSS table.
+
+    Some devices dynamically increase and decrease the size of the RSS
+    indirection table based on the number of enabled queues.
+    When that happens driver must maintain the balance of entries
+    (preferably duplicating the smaller table).
+    """
+
+    channels = cfg.ethnl.channels_get({'header': {'dev-index': cfg.ifindex}})
+    ch_max = channels['combined-max']
+    qcnt = channels['combined-count']
+
+    if ch_max < 2:
+        raise KsftSkipEx(f"Not enough queues for the test: {ch_max}")
+
+    ethtool(f"-L {cfg.ifname} combined 2")
+    defer(ethtool, f"-L {cfg.ifname} combined {qcnt}")
+
+    ethtool(f"-X {cfg.ifname} weight 1 7")
+    defer(ethtool, f"-X {cfg.ifname} default")
+
+    ethtool(f"-L {cfg.ifname} combined {ch_max}")
+    data = get_rss(cfg)
+    ksft_eq(0, min(data['rss-indirection-table']))
+    ksft_eq(1, max(data['rss-indirection-table']))
+
+    ksft_eq(7,
+            data['rss-indirection-table'].count(1) /
+            data['rss-indirection-table'].count(0),
+            f"Table imbalance after resize: {data['rss-indirection-table']}")
+
+
 def test_rss_context(cfg, ctx_cnt=1, create_with_cfg=None):
     """
     Test separating traffic into RSS contexts.
@@ -434,9 +467,11 @@  from lib.py import ethtool, ip, defer, GenerateTraffic, CmdExitFailure
 
 def main() -> None:
     with NetDrvEpEnv(__file__, nsim_test=False) as cfg:
+        cfg.ethnl = EthtoolFamily()
         cfg.netdevnl = NetdevFamily()
 
         ksft_run([test_rss_key_indir, test_rss_queue_reconfigure,
+                  test_rss_resize,
                   test_rss_context, test_rss_context4, test_rss_context32,
                   test_rss_context_queue_reconfigure,
                   test_rss_context_overlap, test_rss_context_overlap2,