rf_gcd
info->FullTablesPerSpareRegion = (v - 1) / rf_gcd(r, v - 1); /* (v-1)/gcd fulltables */
info->FullTablesPerSpareRegion = (v - 1) / rf_gcd(r, v - 1); /* (v-1)/gcd fulltables */
int rf_gcd(int m, int n);