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[testutils] Optimize the runtime of the method verify_no_packet_any for large port sets #231

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[testutils] Optimize the runtime of the method verify_no_packet_any for large port sets #231

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44 changes: 35 additions & 9 deletions src/ptf/testutils.py
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Original file line number Diff line number Diff line change
Expand Up @@ -3328,21 +3328,47 @@ def verify_packets(test, pkt, ports=[], device_number=0, timeout=None, n_timeout
verify_no_other_packets(test, device_number=device_number, timeout=n_timeout)


def verify_no_packet_any(test, pkt, ports=[], device_number=0, timeout=None):
def verify_no_packet_any(test, pkt, ports=[], device_number=0, timeout=1):
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@congh-nvidia congh-nvidia Jan 16, 2026

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The default value of timeout was ptf.ptfutils.default_negative_timeout, we should keep it the same.

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@AntonHryshchuk AntonHryshchuk Jan 18, 2026

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Can't be used with default_negative_timeout as before.
Now, it's a global timeout of the method.
Previously, it was the timeout for a single dp_poll call.
This value(0) is too small for the global timeout.

"""
Check that a packet is NOT received on _any_ of the specified ports belonging to
the given device (default device_number is 0).
Verify that a packet is NOT received on any of the specified ports belonging to
the given device within the given timeout. Uses a single global timeout and repeatedly
polls all ports with zero per-port timeout.
Raises:
test.fail if the packet is received on any of the specified ports.
"""
test.assertTrue(
len(ports) != 0,
"No port available to validate receiving packet on device %d, " % device_number,
)
for device, port in ptf_ports():
if device != device_number:
continue
if port in ports:
print("verifying packet on port device", device_number, "port", port)
verify_no_packet(test, pkt, (device, port), timeout=timeout)
ports = list(ports)
logging.debug("Negative check for pkt on device %d, ports %s", device_number, ports)
start = time.monotonic()
while True:
remaining = timeout - (time.monotonic() - start)
if remaining <= 0:
return # PASS - packet not observed within timeout window

for device, port in ptf_ports():
if device != device_number or port not in ports:
continue

result = dp_poll(
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@roy-sror roy-sror Jan 14, 2026

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you still validate it port-by-port, and not in parallel unless I don't understand the code

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@AntonHryshchuk AntonHryshchuk Jan 14, 2026

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Correct, the validation is still per port, but the key change is that the timeout is now global, not per-port.
Each port is polled in a non-blocking way into a loop bounded by a single timeout window.
It's not parallel, but it reduces the runtime from O(N × timeout) to O(timeout) and still detects packets on any port. Parallel way is not really possible here because the poll operates on a shared dataplane. Polling it from multiple threads not providing additional benefits and can lead to race conditions.

test,
device_number=device_number,
port_number=port,
timeout=0, # non-blocking poll
exp_pkt=pkt,
)

if isinstance(result, test.dataplane.PollSuccess):
test.fail(
"Unexpected packet received on device %d, port %d"
% (device_number, port)
)

# Small sleep to avoid busy-looping and excessive CPU usage.
# Also gives dataplane threads time to enqueue incoming packets.
time.sleep(0.05)


def verify_packets_any(
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