VBD_SHOW_ALLRING
VBD_SHOW_ALLRING(oo_req, "%llu\n");
VBD_SHOW_ALLRING(rd_req, "%llu\n");
VBD_SHOW_ALLRING(wr_req, "%llu\n");
VBD_SHOW_ALLRING(f_req, "%llu\n");
VBD_SHOW_ALLRING(ds_req, "%llu\n");
VBD_SHOW_ALLRING(rd_sect, "%llu\n");
VBD_SHOW_ALLRING(wr_sect, "%llu\n");