Merge pull request #17102 from mychoxin/yuanxin_print_log_if_add_even…

…t_fail

msg/async: print error log if add_event fail

Reviewed-by: Pan Liu <liupan1111@gmail.com>
Reviewed-by: Jos Collin <jcollin@redhat.com>

src/msg/async/Event.cc

@@ -230,6 +230,8 @@ int EventCenter::create_file_event(int fd, int mask, EventCallbackRef ctxt)
     // Actually we don't allow any failed error code, caller doesn't prepare to
     // handle error status. So now we need to assert failure here. In practice,
     // add_event shouldn't report error, otherwise it must be a innermost bug!
+    lderr(cct) << __func__ << " add event failed, ret=" << r << " fd=" << fd
+               << " mask=" << mask << " original mask is " << event->mask << dendl;
     assert(0 == "BUG!");
     return r;
   }