Method _get_session

src/osdc/Objecter.cc:1921–1956

* Look up OSDSession by OSD id. * * @returns 0 on success, or -EAGAIN if the lock context requires * promotion to write. */

 * promotion to write.
 */
int Objecter::_get_session(int osd, OSDSession **session,
			   shunique_lock<ceph::shared_mutex>& sul)
{
  ceph_assert(sul && sul.mutex() == &rwlock);

  if (osd < 0) {
    *session = homeless_session;
    ldout(cct, 20) << __func__ << " osd=" << osd << " returning homeless"
		   << dendl;
    return 0;
  }

  auto p = osd_sessions.find(osd);
  if (p != osd_sessions.end()) {
    auto s = p->second;
    s->get();
    *session = s;
    ldout(cct, 20) << __func__ << " s=" << s << " osd=" << osd << " "
		   << s->get_nref() << dendl;
    return 0;
  }
  if (!sul.owns_lock()) {
    return -EAGAIN;
  }
  auto s = new OSDSession(cct, osd);
  osd_sessions[osd] = s;
  s->con = messenger->connect_to_osd(osdmap->get_addrs(osd));
  s->con->set_priv(RefCountedPtr{s});
  logger->inc(l_osdc_osd_session_open);
  logger->set(l_osdc_osd_sessions, osd_sessions.size());
  s->get();
  *session = s;
  ldout(cct, 20) << __func__ << " s=" << s << " osd=" << osd << " "
		 << s->get_nref() << dendl;
  return 0;
}

void Objecter::put_session(Objecter::OSDSession *s)
{