Function initialize_thread_for_udp_net

src/iocore/net/UnixUDPNet.cc:235–295

sockaddr_in6 G_bwGrapherLoc;

void
initialize_thread_for_udp_net(EThread *thread)
{
  int enable_gso, enable_gro;
  REC_ReadConfigInteger(enable_gso, "proxy.config.udp.enable_gso");
  REC_ReadConfigInteger(enable_gro, "proxy.config.udp.enable_gro");

  UDPNetHandler *nh = get_UDPNetHandler(thread);

  UDPNetHandler::Cfg cfg{static_cast<bool>(enable_gso), static_cast<bool>(enable_gro)};

  G_udp_config = cfg; // keep a global copy.
  new (reinterpret_cast<ink_dummy_for_new *>(nh)) UDPNetHandler(std::move(cfg));

#ifndef SOL_UDP
  if (G_udp_config.enable_gro) {
    Warning("Attempted to use UDP GRO per configuration, but it is unavailable");
  }
#endif

  new (reinterpret_cast<ink_dummy_for_new *>(get_UDPPollCont(thread))) PollCont(thread->mutex);
  // The UDPNetHandler cannot be accessed across EThreads.
  // Because the UDPNetHandler should be called back immediately after UDPPollCont.
  nh->mutex  = thread->mutex.get();
  nh->thread = thread;

  PollCont       *upc = get_UDPPollCont(thread);
  PollDescriptor *upd = upc->pollDescriptor;

  REC_ReadConfigInteger(g_udp_pollTimeout, "proxy.config.udp.poll_timeout");
  upc->poll_timeout = g_udp_pollTimeout;

  // This variable controls how often we cleanup the cancelled packets.
  // If it is set to 0, then cleanup never occurs.
  REC_ReadConfigInt32(g_udp_periodicFreeCancelledPkts, "proxy.config.udp.free_cancelled_pkts_sec");

  // This variable controls how many "slots" of the udp calendar queue we cleanup.
  // If it is set to 0, then cleanup never occurs.  This value makes sense
  // only if the above variable is set.
  REC_ReadConfigInt32(g_udp_periodicCleanupSlots, "proxy.config.udp.periodic_cleanup");

  // UDP sends can fail with errno=EAGAIN.  This variable determines the # of
  // times the UDP thread retries before giving up.  Set to 0 to keep trying forever.
  REC_ReadConfigInt32(g_udp_numSendRetries, "proxy.config.udp.send_retries");
  g_udp_numSendRetries = g_udp_numSendRetries < 0 ? 0 : g_udp_numSendRetries;

  thread->set_tail_handler(nh);
#if HAVE_EVENTFD
#if TS_USE_LINUX_IO_URING
  auto ep = new IOUringEventIO();
  ep->start(upd, IOUringContext::local_context());
#else
  auto ep = new AsyncSignalEventIO();
  ep->start(upd, thread->evfd, EVENTIO_READ);
#endif
#else
  auto ep = new AsyncSignalEventIO();
  ep->start(upd, thread->evpipe[0], EVENTIO_READ);