Method early_reply

src/mds/Server.cc:2289–2361

}

void Server::early_reply(const MDRequestRef& mdr, CInode *tracei, CDentry *tracedn)
{
  if (!g_conf()->mds_early_reply)
    return;

  if (mdr->no_early_reply) {
    dout(10) << "early_reply - flag no_early_reply is set, not allowed." << dendl;
    return;
  }

  if (mdr->has_more() && mdr->more()->has_journaled_peers) {
    dout(10) << "early_reply - there are journaled peers, not allowed." << dendl;
    return; 
  }

  if (mdr->alloc_ino) {
    dout(10) << "early_reply - allocated ino, not allowed" << dendl;
    return;
  }

  const cref_t<MClientRequest> &req = mdr->client_request;
  entity_inst_t client_inst = req->get_source_inst();
  if (client_inst.name.is_mds())
    return;

  if (req->is_replay()) {
    dout(10) << " no early reply on replay op" << dendl;
    return;
  }


  auto reply = ceph::make_message<MClientReply>(*req, 0);
  reply->set_unsafe();

  // mark xlocks "done", indicating that we are exposing uncommitted changes.
  //
  //_rename_finish() does not send dentry link/unlink message to replicas.
  // so do not set xlocks on dentries "done", the xlocks prevent dentries
  // that have projected linkages from getting new replica.
  mds->locker->set_xlocks_done(mdr.get(), req->get_op() == CEPH_MDS_OP_RENAME);

  dout(10) << "early_reply " << reply->get_result() 
	   << " (" << cpp_strerror(reply->get_result())
	   << ") " << *req << dendl;

  if (tracei || tracedn) {
    if (tracei)
      mdr->cap_releases.erase(tracei->vino());
    if (tracedn)
      mdr->cap_releases.erase(tracedn->get_dir()->get_inode()->vino());

    set_trace_dist(reply, tracei, tracedn, mdr);
  }

  reply->set_extra_bl(mdr->reply_extra_bl);
  mds->send_message_client(reply, mdr->session);

  mdr->did_early_reply = true;