isis dce接收到报文的流程

(gdb) bt
#1  0x00007ffff7a4a67f in ns3::UnixDatagramSocketFd::DoRecvmsg (this=0x7fffe402eb50, msg=0x7ffff45847f0, flags=2) at ../model/unix-datagram-socket-fd.cc:187
#2  0x00007ffff7a419a4 in ns3::UnixSocketFd::Recvmsg (this=0x7fffe402eb50, msg=0x7ffff45847f0, flags=2) at ../model/unix-socket-fd.cc:227
#3  0x00007ffff7a5e537 in dce_recvmsg (fd=8, msg=0x7ffff45847f0, flags=2) at ../model/dce-fd.cc:527
#4  0x00007ffff7a5e1a1 in dce_recvfrom (fd=8, buf=0x7ffff4584b10, len=3, flags=2, from=0x7ffff4584b20, fromlen=0x7ffff4584b38) at ../model/dce-fd.cc:504
#5  0x00007ffff5472ae1 in recvfrom () at ../model/libc-ns3.h:192
#6  0x00007ffff42e0fdf in isis_recv_pdu_bcast (circuit=0x7ffff427d8c8, ssnpa=0x7ffff4584b60 "\200KX\364\377\177") at isis_pfpacket.c:231
#7  0x00007ffff42cf57a in isis_receive (thread=0x7ffff4584cc0) at isis_pdu.c:1792
#8  0x00007ffff42f34ef in thread_call (thread=0x7ffff4584cc0) at thread.c:1177
#9  0x00007ffff42bea3d in main (argc=5, argv=0x66c3c0, envp=0x6470b0) at isis_main.c:353
#10 0x00007ffff7a06fef in ns3::DceManager::DoStartProcess (context=0x676ba0) at ../model/dce-manager.cc:283
#11 0x00007ffff7a90238 in ns3::TaskManager::Trampoline (context=0x663660) at ../model/task-manager.cc:274
#12 0x00007ffff7a8c213 in ns3::PthreadFiberManager::Run (arg=0x676e90) at ../model/pthread-fiber-manager.cc:402
#13 0x000000318b2079d1 in start_thread () from /lib64/libpthread.so.0
#14 0x000000318a6e88fd in clone () from /lib64/libc.so.6
(gdb)