selftest: net-drv: hds: add test for HDS feature

HDS/HDS-thresh features were updated/implemented. so add some tests for
these features.

HDS tests are the same with `ethtool -G eth0 tcp-data-split <on | off |
auto >` but `auto` depends on driver specification.
So, it doesn't include `auto` case.

HDS-thresh tests are same with `ethtool -G eth0 hds-thresh <0 - MAX>`
It includes both 0 and MAX cases. It also includes exceed case, MAX + 1.

Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Link: https://patch.msgid.link/20250114142852.3364986-11-ap420073@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

tools/testing/selftests/drivers/net/Makefile

@@ -12,6 +12,7 @@ TEST_PROGS := \
 	queues.py \
 	stats.py \
 	shaper.py \
+	hds.py \
 # end of TEST_PROGS
 
 include ../../lib.mk

tools/testing/selftests/drivers/net/hds.py

@@ -0,0 +1,120 @@
+#!/usr/bin/env python3
+# SPDX-License-Identifier: GPL-2.0
+
+import errno
+from lib.py import ksft_run, ksft_exit, ksft_eq, ksft_raises, KsftSkipEx
+from lib.py import EthtoolFamily, NlError
+from lib.py import NetDrvEnv
+
+def get_hds(cfg, netnl) -> None:
+    try:
+        rings = netnl.rings_get({'header': {'dev-index': cfg.ifindex}})
+    except NlError as e:
+        raise KsftSkipEx('ring-get not supported by device')
+    if 'tcp-data-split' not in rings:
+        raise KsftSkipEx('tcp-data-split not supported by device')
+
+def get_hds_thresh(cfg, netnl) -> None:
+    try:
+        rings = netnl.rings_get({'header': {'dev-index': cfg.ifindex}})
+    except NlError as e:
+        raise KsftSkipEx('ring-get not supported by device')
+    if 'hds-thresh' not in rings:
+        raise KsftSkipEx('hds-thresh not supported by device')
+
+def set_hds_enable(cfg, netnl) -> None:
+    try:
+        netnl.rings_set({'header': {'dev-index': cfg.ifindex}, 'tcp-data-split': 'enabled'})
+    except NlError as e:
+        if e.error == errno.EINVAL:
+            raise KsftSkipEx("disabling of HDS not supported by the device")
+        elif e.error == errno.EOPNOTSUPP:
+            raise KsftSkipEx("ring-set not supported by the device")
+    try:
+        rings = netnl.rings_get({'header': {'dev-index': cfg.ifindex}})
+    except NlError as e:
+        raise KsftSkipEx('ring-get not supported by device')
+    if 'tcp-data-split' not in rings:
+        raise KsftSkipEx('tcp-data-split not supported by device')
+
+    ksft_eq('enabled', rings['tcp-data-split'])
+
+def set_hds_disable(cfg, netnl) -> None:
+    try:
+        netnl.rings_set({'header': {'dev-index': cfg.ifindex}, 'tcp-data-split': 'disabled'})
+    except NlError as e:
+        if e.error == errno.EINVAL:
+            raise KsftSkipEx("disabling of HDS not supported by the device")
+        elif e.error == errno.EOPNOTSUPP:
+            raise KsftSkipEx("ring-set not supported by the device")
+    try:
+        rings = netnl.rings_get({'header': {'dev-index': cfg.ifindex}})
+    except NlError as e:
+        raise KsftSkipEx('ring-get not supported by device')
+    if 'tcp-data-split' not in rings:
+        raise KsftSkipEx('tcp-data-split not supported by device')
+
+    ksft_eq('disabled', rings['tcp-data-split'])
+
+def set_hds_thresh_zero(cfg, netnl) -> None:
+    try:
+        netnl.rings_set({'header': {'dev-index': cfg.ifindex}, 'hds-thresh': 0})
+    except NlError as e:
+        if e.error == errno.EINVAL:
+            raise KsftSkipEx("hds-thresh-set not supported by the device")
+        elif e.error == errno.EOPNOTSUPP:
+            raise KsftSkipEx("ring-set not supported by the device")
+    try:
+        rings = netnl.rings_get({'header': {'dev-index': cfg.ifindex}})
+    except NlError as e:
+        raise KsftSkipEx('ring-get not supported by device')
+    if 'hds-thresh' not in rings:
+        raise KsftSkipEx('hds-thresh not supported by device')
+
+    ksft_eq(0, rings['hds-thresh'])
+
+def set_hds_thresh_max(cfg, netnl) -> None:
+    try:
+        rings = netnl.rings_get({'header': {'dev-index': cfg.ifindex}})
+    except NlError as e:
+        raise KsftSkipEx('ring-get not supported by device')
+    if 'hds-thresh' not in rings:
+        raise KsftSkipEx('hds-thresh not supported by device')
+    try:
+        netnl.rings_set({'header': {'dev-index': cfg.ifindex}, 'hds-thresh': rings['hds-thresh-max']})
+    except NlError as e:
+        if e.error == errno.EINVAL:
+            raise KsftSkipEx("hds-thresh-set not supported by the device")
+        elif e.error == errno.EOPNOTSUPP:
+            raise KsftSkipEx("ring-set not supported by the device")
+    rings = netnl.rings_get({'header': {'dev-index': cfg.ifindex}})
+    ksft_eq(rings['hds-thresh'], rings['hds-thresh-max'])
+
+def set_hds_thresh_gt(cfg, netnl) -> None:
+    try:
+        rings = netnl.rings_get({'header': {'dev-index': cfg.ifindex}})
+    except NlError as e:
+        raise KsftSkipEx('ring-get not supported by device')
+    if 'hds-thresh' not in rings:
+        raise KsftSkipEx('hds-thresh not supported by device')
+    if 'hds-thresh-max' not in rings:
+        raise KsftSkipEx('hds-thresh-max not defined by device')
+    hds_gt = rings['hds-thresh-max'] + 1
+    with ksft_raises(NlError) as e:
+        netnl.rings_set({'header': {'dev-index': cfg.ifindex}, 'hds-thresh': hds_gt})
+    ksft_eq(e.exception.nl_msg.error, -errno.EINVAL)
+
+def main() -> None:
+    with NetDrvEnv(__file__, queue_count=3) as cfg:
+        ksft_run([get_hds,
+                  get_hds_thresh,
+                  set_hds_disable,
+                  set_hds_enable,
+                  set_hds_thresh_zero,
+                  set_hds_thresh_max,
+                  set_hds_thresh_gt],
+                 args=(cfg, EthtoolFamily()))
+    ksft_exit()
+
+if __name__ == "__main__":
+    main()