static struct thread *get_main_thread(struct machine *machine, struct thread *thread)
 {
        if (thread->pid_ == thread->tid)
-               return thread;
+               return thread__get(thread);
 
        if (thread->pid_ == -1)
                return NULL;
        if (err)
                return err;
 
-       /* FIXME: check refcounting for get_main_thread, that calls machine__find_thread... */
        main_thread = get_main_thread(al->machine, thread);
        if (main_thread)
                comm = machine__thread_exec_comm(al->machine, main_thread);
 
        err = db_export__thread(dbe, thread, al->machine, comm);
        if (err)
-               return err;
+               goto out_put;
 
        if (comm) {
                err = db_export__comm(dbe, comm, main_thread);
                if (err)
-                       return err;
+                       goto out_put;
                es.comm_db_id = comm->db_id;
        }
 
 
        err = db_ids_from_al(dbe, al, &es.dso_db_id, &es.sym_db_id, &es.offset);
        if (err)
-               return err;
+               goto out_put;
 
        if ((evsel->attr.sample_type & PERF_SAMPLE_ADDR) &&
            sample_addr_correlates_sym(&evsel->attr)) {
                err = db_ids_from_al(dbe, &addr_al, &es.addr_dso_db_id,
                                     &es.addr_sym_db_id, &es.addr_offset);
                if (err)
-                       return err;
+                       goto out_put;
                if (dbe->crp) {
                        err = thread_stack__process(thread, comm, sample, al,
                                                    &addr_al, es.db_id,
                                                    dbe->crp);
                        if (err)
-                               return err;
+                               goto out_put;
                }
        }
 
        if (dbe->export_sample)
-               return dbe->export_sample(dbe, &es);
+               err = dbe->export_sample(dbe, &es);
 
-       return 0;
+out_put:
+       thread__put(main_thread);
+       return err;
 }
 
 static struct {