Fix a prof_tctx_t/prof_tdata_t cleanup race by storing a copy of thr_uid in prof_tctx_t, so that the associated tdata need not be present during tctx teardown.
Fix a prof_tctx_t/prof_tdata_t cleanup race by storing a copy of thr_uid in prof_tctx_t, so that the associated tdata need not be present during tctx teardown.