diff options
| -rw-r--r-- | test/vpp_pg_interface.py | 40 |
1 files changed, 32 insertions, 8 deletions
diff --git a/test/vpp_pg_interface.py b/test/vpp_pg_interface.py index 756f79b5609..81737c6d567 100644 --- a/test/vpp_pg_interface.py +++ b/test/vpp_pg_interface.py @@ -1,8 +1,9 @@ import os import time import socket -from traceback import format_exc +from traceback import format_exc, format_stack from scapy.utils import wrpcap, rdpcap, PcapReader +from scapy.plist import PacketList from vpp_interface import VppInterface from scapy.layers.l2 import Ether, ARP @@ -84,6 +85,7 @@ class VppPGInterface(VppInterface): self._in_history_counter = 0 self._out_history_counter = 0 + self._out_assert_counter = 0 self._pg_index = pg_index self._out_file = "pg%u_out.pcap" % self.pg_index self._out_path = self.test.tempdir + "/" + self._out_file @@ -136,6 +138,22 @@ class VppPGInterface(VppInterface): # FIXME this should be an API, but no such exists atm self.test.vapi.cli(self.input_cli) + def generate_debug_aid(self, kind): + """ Create a hardlink to the out file with a counter and a file + containing stack trace to ease debugging in case of multiple capture + files present. """ + self.test.logger.debug("Generating debug aid for %s on %s" % + (kind, self._name)) + link_path, stack_path = ["%s/debug_%s_%s_%s.%s" % + (self.test.tempdir, self._name, + self._out_assert_counter, kind, suffix) + for suffix in ["pcap", "stack"] + ] + os.link(self.out_path, link_path) + with open(stack_path, "w") as f: + f.writelines(format_stack()) + self._out_assert_counter += 1 + def _get_capture(self, timeout, filter_out_fn=is_ipv6_misc): """ Helper method to get capture and filter it """ try: @@ -150,7 +168,7 @@ class VppPGInterface(VppInterface): before = len(output.res) if filter_out_fn: output.res = [p for p in output.res if not filter_out_fn(p)] - removed = len(output.res) - before + removed = before - len(output.res) if removed: self.test.logger.debug( "Filtered out %s packets from capture (returning %s)" % @@ -184,9 +202,6 @@ class VppPGInterface(VppInterface): name) self.test.logger.debug("Expecting to capture %s (%s) packets on %s" % ( expected_count, based_on, name)) - if expected_count == 0: - raise Exception( - "Internal error, expected packet count for %s is 0!" % name) while remaining_time > 0: before = time.time() capture = self._get_capture(remaining_time, filter_out_fn) @@ -195,8 +210,17 @@ class VppPGInterface(VppInterface): if len(capture.res) == expected_count: # bingo, got the packets we expected return capture + else: + self.test.logger.debug("Partial capture containing %s " + "packets doesn't match expected " + "count %s (yet?)" % + (len(capture.res), expected_count)) + elif expected_count == 0: + # bingo, got None as we expected - return empty capture + return PacketList() remaining_time -= elapsed_time if capture: + self.generate_debug_aid("count-mismatch") raise Exception("Captured packets mismatch, captured %s packets, " "expected %s packets on %s" % (len(capture.res), expected_count, name)) @@ -214,13 +238,14 @@ class VppPGInterface(VppInterface): try: capture = self.get_capture( 0, remark=remark, filter_out_fn=filter_out_fn) - if not capture: + if not capture or len(capture.res) == 0: # junk filtered out, we're good return self.test.logger.error( ppc("Unexpected packets captured:", capture)) except: pass + self.generate_debug_aid("empty-assert") if remark: raise AssertionError( "Non-empty capture file present for interface %s (%s)" % @@ -278,8 +303,7 @@ class VppPGInterface(VppInterface): break except: self.test.logger.debug( - "Exception in scapy.PcapReader(%s): " - "%s" % + "Exception in scapy.PcapReader(%s): %s" % (self.out_path, format_exc())) if not self._pcap_reader: raise Exception("Capture file %s did not appear within " |