diff --git a/tools/testing/selftests/drivers/net/config b/tools/testing/selftests/drivers/net/config index 2070e890e064..f3933cf3e6be 100644 --- a/tools/testing/selftests/drivers/net/config +++ b/tools/testing/selftests/drivers/net/config @@ -4,8 +4,11 @@ CONFIG_DEBUG_INFO_BTF_MODULES=n CONFIG_INET_PSP=y CONFIG_IPV6=y CONFIG_MACSEC=m +CONFIG_NET_ACT_SKBEDIT=m CONFIG_NET_CLS_ACT=y CONFIG_NET_CLS_BPF=y +CONFIG_NET_CLS_FLOWER=m +CONFIG_NET_CLS_MATCHALL=m CONFIG_NETCONSOLE=m CONFIG_NETCONSOLE_DYNAMIC=y CONFIG_NETCONSOLE_EXTENDED_LOG=y diff --git a/tools/testing/selftests/drivers/net/lib/py/env.py b/tools/testing/selftests/drivers/net/lib/py/env.py index e4acf3d8333f..b1c6f6cef7dd 100644 --- a/tools/testing/selftests/drivers/net/lib/py/env.py +++ b/tools/testing/selftests/drivers/net/lib/py/env.py @@ -114,10 +114,11 @@ class NetDrvEpEnv(NetDrvEnvBase): nsim_v4_pfx = "192.0.2." nsim_v6_pfx = "2001:db8::" - def __init__(self, src_path, nsim_test=None): + def __init__(self, src_path, nsim_test=None, queue_count=None): super().__init__(src_path) self._stats_settle_time = None + self._queue_count = queue_count # Things we try to destroy self.remote = None @@ -173,9 +174,13 @@ class NetDrvEpEnv(NetDrvEnvBase): self._required_cmd = {} def create_local(self): + nsim_kwargs = {} + if self._queue_count: + nsim_kwargs["queue_count"] = self._queue_count + self._netns = NetNS() - self._ns = NetdevSimDev() - self._ns_peer = NetdevSimDev(ns=self._netns) + self._ns = NetdevSimDev(**nsim_kwargs) + self._ns_peer = NetdevSimDev(ns=self._netns, **nsim_kwargs) with open("/proc/self/ns/net") as nsfd0, \ open("/var/run/netns/" + self._netns.name) as nsfd1: diff --git a/tools/testing/selftests/drivers/net/ring_reconfig.py b/tools/testing/selftests/drivers/net/ring_reconfig.py index f9530a8b0856..2bc329b77134 100755 --- a/tools/testing/selftests/drivers/net/ring_reconfig.py +++ b/tools/testing/selftests/drivers/net/ring_reconfig.py @@ -5,10 +5,25 @@ Test channel and ring size configuration via ethtool (-L / -G). """ +import socket +import struct +import time + from lib.py import ksft_run, ksft_exit, ksft_pr from lib.py import ksft_eq +from lib.py import KsftSkipEx, KsftXfailEx from lib.py import NetDrvEpEnv, EthtoolFamily, GenerateTraffic -from lib.py import defer, NlError +from lib.py import cmd, defer, rand_port, tc, NlError + +# Added in Python 3.13; fallback to 61 for x86/ARM/MIPS +SO_TXTIME = getattr(socket, "SO_TXTIME", 61) + +# Not always exported by the socket module; asm-generic value (x86/ARM/MIPS). +SO_SNDBUFFORCE = getattr(socket, "SO_SNDBUFFORCE", 32) + +# TX ring size the test shrinks to so the ring fills quickly. +MIN_TX_RING = 32 +MAX_TX_RING = 1024 def channels(cfg) -> None: @@ -151,14 +166,248 @@ def ringparam(cfg) -> None: GenerateTraffic(cfg).wait_pkts_and_stop(10000) +def _write_file(path, val): + """Write val to a file.""" + with open(path, "w", encoding="utf-8") as fp: + fp.write(str(val)) + + +def _write_sysfs(path, val): + """Write val to a sysfs file, restoring the original value on exit.""" + with open(path, "r", encoding="utf-8") as fp: + orig_val = fp.read().strip() + if str(val) == orig_val: + return + _write_file(path, val) + defer(_write_file, path, orig_val) + + +def _get_qdisc_backlog(cfg, mq_handle, queue): + """Return the qdisc backlog (bytes) for the given TX queue's leaf.""" + target_parent = f"{mq_handle}{queue + 1:x}" + for q in tc(f"-s qdisc show dev {cfg.ifname}", json=True): + if q.get("parent", "") == target_parent: + return q.get("backlog") or 0 + return 0 + + +def _setup_fq_qdisc(cfg, port, target_queue, other_queue, flow_limit): + """Put an fq qdisc on target_queue's leaf and return the mq handle in use. + + We must not disturb the device's existing TX/RX qdisc policy. On a real + NIC the root mq already has an addressable handle, so we leave the root + and every other queue alone and only swap this one leaf, restoring its + original qdisc afterwards. + + @flow_limit raises fq's per-flow packet limit (default 100) so a single + flow can back up more packets than the Tx ring holds and thus overflow it. + """ + qdiscs = tc(f"qdisc show dev {cfg.ifname}", json=True) + root = next((q for q in qdiscs if q.get("root")), None) + + if root and root["kind"] == "mq" and root["handle"] != "0:": + # Addressable mq (previously-configured): touch only the target queue's + # leaf and restore its original qdisc afterwards. + mq_handle = root["handle"] + parent = f"{mq_handle}{target_queue + 1:x}" + orig = next((q for q in qdiscs if q.get("parent") == parent), None) + orig_kind = orig["kind"] if orig else \ + cmd("sysctl -n net.core.default_qdisc").stdout.strip() + defer(tc, f"qdisc replace dev {cfg.ifname} parent {parent} {orig_kind}") + elif root is None or root["kind"] in ("mq", "noqueue"): + # The auto-attached root mq has handle 0: on any device (real or sim), + # which the kernel rejects as a qdisc parent. A 0: handle means the mq + # is the untouched kernel default - no custom child qdiscs can hang off + # an unaddressable parent - so installing a real handle and restoring + # the default mq on exit preserves the device's effective policy. + mq_handle = "1:" + tc(f"qdisc replace dev {cfg.ifname} root handle {mq_handle} mq") + defer(tc, f"qdisc replace dev {cfg.ifname} root mq") + parent = f"{mq_handle}{target_queue + 1:x}" + else: + raise KsftSkipEx(f"root qdisc '{root['kind']}' is not mq; " + "refusing to disturb existing qdisc policy") + + try: + tc(f"qdisc replace dev {cfg.ifname} parent {parent} fq " + f"flow_limit {flow_limit} limit {flow_limit * 2}") + except Exception as exc: + raise KsftSkipEx( + f"fq not available (CONFIG_NET_SCH_FQ): {exc}") from exc + + qdisc_j = tc(f"qdisc show dev {cfg.ifname}", json=True) + has_clsact = any(q['kind'] == 'clsact' for q in qdisc_j) + if not has_clsact: + tc(f"qdisc add dev {cfg.ifname} clsact") + defer(tc, f"qdisc del dev {cfg.ifname} clsact") + + proto = "ipv6" if int(cfg.addr_ipver) == 6 else "ip" + try: + tc(f"filter add dev {cfg.ifname} egress protocol {proto} " + f"pref 1 flower ip_proto udp dst_port {port} " + f"action skbedit queue_mapping {target_queue}") + except Exception as exc: + raise KsftSkipEx("tc flower/act_skbedit not available") from exc + defer(tc, f"filter del dev {cfg.ifname} egress pref 1") + + tc(f"filter add dev {cfg.ifname} egress pref 101 " + f"matchall action skbedit queue_mapping {other_queue}") + defer(tc, f"filter del dev {cfg.ifname} egress pref 101") + + return mq_handle + + +def _create_sotxtime_socket(cfg, sndbuf): + """Create a UDP socket with SO_TXTIME enabled, bound to the test device.""" + sock = socket.socket(socket.AF_INET6 if cfg.addr_ipver == "6" + else socket.AF_INET, socket.SOCK_DGRAM) + try: + sock.setsockopt(socket.SOL_SOCKET, SO_TXTIME, struct.pack("Ii", 1, 0)) + except OSError as exc: + sock.close() + raise KsftSkipEx("SO_TXTIME not supported") from exc + sock.setsockopt(socket.SOL_SOCKET, socket.SO_BINDTODEVICE, + cfg.ifname.encode()) + # Deferred completions keep every in-flight skb charged to the socket, so + # size the send buffer to hold the whole burst. SO_SNDBUFFORCE bypasses + # net.core.wmem_max (the test runs as root). + try: + sock.setsockopt(socket.SOL_SOCKET, SO_SNDBUFFORCE, sndbuf) + except OSError: + sock.setsockopt(socket.SOL_SOCKET, socket.SO_SNDBUF, sndbuf) + return sock + + +def _send_sotxtime_burst(cfg, sock, port, count, delay_ns, pkt_size): + """Send count UDP packets scheduled delay_ns ahead using SO_TXTIME.""" + payload = b'\x00' * pkt_size + txtime_ns = time.clock_gettime_ns(time.CLOCK_MONOTONIC) + delay_ns + + ancdata = [(socket.SOL_SOCKET, SO_TXTIME, struct.pack("Q", txtime_ns))] + if int(cfg.addr_ipver) == 6: + dest = (cfg.remote_addr, port, 0, 0) + else: + dest = (cfg.remote_addr, port) + for _ in range(count): + sock.sendmsg([payload], ancdata, 0, dest) + + +def _set_small_tx_ring(cfg, ehdr): + """Set the Tx ring to the smallest size the driver accepts. + + Start at 32 so the ring fills quickly, then grow exponentially (64, + 128, 256, ...) up to 1024. Some drivers enforce a minimum well above 32 + (e.g. bnxt needs a large ring for software UDP segmentation), so raise + the lower bound until the driver accepts it, giving up past 1024. + """ + size = MIN_TX_RING + while size <= MAX_TX_RING: + try: + cfg.eth.rings_set(ehdr | {'tx': size}) + return size + except NlError: + size = size * 2 + continue + raise KsftSkipEx("driver rejects all tx ring sizes up to 1024") + + +def reconfig_tx_stall(cfg) -> None: + """Test that qdisc backlog drains after ring reconfiguration.""" + target_queue = 1 + other_queue = 0 + + ehdr = {'header': {'dev-index': cfg.ifindex}} + chans = cfg.eth.channels_get(ehdr) + + if "combined-max" not in chans: + raise KsftSkipEx("device does not support combined channels") + if chans.get("combined-max", 0) < 2: + raise KsftSkipEx("device does not support 2+ combined channels") + if chans["combined-count"] < 2: + defer(cfg.eth.channels_set, + ehdr | {"combined-count": chans["combined-count"]}) + cfg.eth.channels_set(ehdr | {"combined-count": 2}) + + rings = cfg.eth.rings_get(ehdr) + if 'rx' not in rings or 'tx' not in rings: + raise KsftSkipEx("device does not expose rx/tx ring params") + tx_cur = rings['tx'] + if tx_cur <= MIN_TX_RING: + raise KsftSkipEx("tx ring size already at minimum") + defer(cfg.eth.rings_set, ehdr | {'tx': tx_cur}) + + # Use the smallest Tx ring the driver accepts (32, growing to 1024). + tx_ring = _set_small_tx_ring(cfg, ehdr) + + # Slow completions so the ring stays full after FQ releases packets + napi_defer = f"/sys/class/net/{cfg.ifname}/napi_defer_hard_irqs" + gro_timeout = f"/sys/class/net/{cfg.ifname}/gro_flush_timeout" + _write_sysfs(napi_defer, 100) + _write_sysfs(gro_timeout, 1000000000) + + port = rand_port() + # A single flow must overflow the ring, so send twice the ring depth and + # let fq hold that many packets for the flow. + pkt_count = tx_ring * 2 + mq_handle = _setup_fq_qdisc(cfg, port, target_queue, other_queue, + tx_ring * 2) + + # Size each packet to one MTU (less L3/L4 headers to avoid fragmentation). + pkt_size = cfg.dev['mtu'] - (48 if int(cfg.addr_ipver) == 6 else 28) + + # Each queued skb charges the socket its truesize (~2x the payload), so + # budget the send buffer for the whole in-flight burst. + sock = _create_sotxtime_socket(cfg, pkt_count * pkt_size * 2) + defer(sock.close) + + for delay_ms in [100, 200, 500]: + _send_sotxtime_burst(cfg, sock, port, pkt_count, + delay_ms * 1_000_000, pkt_size) + ksft_pr(f"Sent {pkt_count} SO_TXTIME packets (+{delay_ms}ms)") + time.sleep(delay_ms / 1000 + 0.3) + + backlog = _get_qdisc_backlog(cfg, mq_handle, target_queue) + if backlog: + break + else: + # A device that completes Tx synchronously (e.g. a software/virtual + # driver like netdevsim) never keeps the ring full long enough for a + # backlog to form, so the wake-vs-start behavior can't be exercised. + # Treat that as an expected failure rather than a hard failure. + raise KsftXfailEx("could not build qdisc backlog") + + ksft_pr(f"Backlog before reconfig: {backlog} bytes") + + # Trigger ring reconfig — driver should call wake, not just start. + # Grow back to the original size so the driver actually switches channels + # (setting the current size is a no-op the driver short-circuits). + cfg.eth.rings_set(ehdr | {'tx': tx_cur}) + + # Let completions proceed normally + _write_sysfs(napi_defer, 0) + _write_sysfs(gro_timeout, 0) + + # Poll for backlog to drain + for _ in range(100): + backlog = _get_qdisc_backlog(cfg, mq_handle, target_queue) + if not backlog: + break + time.sleep(0.1) + + ksft_eq(0, backlog, + comment=f"qdisc backlog stuck on queue {target_queue} " + f"after ring reconfig") + + def main() -> None: """ Ksft boiler plate main """ - with NetDrvEpEnv(__file__) as cfg: + with NetDrvEpEnv(__file__, queue_count=2) as cfg: cfg.eth = EthtoolFamily() ksft_run([channels, - ringparam], + ringparam, + reconfig_tx_stall], args=(cfg, )) ksft_exit()