RGW tracing

Hello everyone I m trying to implement jaeger tracing in rgw. I m storing my spans in struct req_state, but some files rgw_sal.cc and rgw_user.cc dont have anything relation to req_state so I thought of using extern variable to store req_state, it is wrong because req can run in parellel, so another way of using it I included data members req_state in RGWRadosStore and RGWCtrl class then using those to access the req_state and storing the spans Is it the right move of adding extra data members in classes?