Cache related tests (like CAT and CMT) depend on a variable called no_of_bits to run. no_of_bits defines the number of contiguous bits that should be set in the CBM mask and a user can pass a value for no_of_bits using -n command line argument. If a user hasn't passed any value, it defaults to 5 (randomly chosen value).
Hard coding no_of_bits to 5 will make the cache tests fail to run on systems that support maximum cbm mask that is less than or equal to 5 bits. Hence, don't hard code no_of_bits value.
If a user passes a value for "no_of_bits" using -n option, use it. Otherwise, no_of_bits is equal to half of the maximum number of bits in the cbm mask.
Please note that CMT test is still hard coded to 5 bits. It will change in subsequent patches that change CMT test.
Fixes: 790bf585b0ee ("selftests/resctrl: Add Cache Allocation Technology (CAT) selftest") Signed-off-by: Fenghua Yu fenghua.yu@intel.com --- tools/testing/selftests/resctrl/cat_test.c | 5 ++++- tools/testing/selftests/resctrl/resctrl_tests.c | 8 ++++++-- 2 files changed, 10 insertions(+), 3 deletions(-)
diff --git a/tools/testing/selftests/resctrl/cat_test.c b/tools/testing/selftests/resctrl/cat_test.c index 5da43767b973..1bce84e23783 100644 --- a/tools/testing/selftests/resctrl/cat_test.c +++ b/tools/testing/selftests/resctrl/cat_test.c @@ -151,7 +151,10 @@ int cat_perf_miss_val(int cpu_no, int n, char *cache_type) /* Get max number of bits from default-cabm mask */ count_of_bits = count_bits(long_mask);
- if (n < 1 || n > count_of_bits - 1) { + if (!n) + n = count_of_bits / 2; + + if (n > count_of_bits - 1) { printf("Invalid input value for no_of_bits n!\n"); printf("Please Enter value in range 1 to %d\n", count_of_bits - 1); diff --git a/tools/testing/selftests/resctrl/resctrl_tests.c b/tools/testing/selftests/resctrl/resctrl_tests.c index f4867a81eee6..5c217d0228f4 100644 --- a/tools/testing/selftests/resctrl/resctrl_tests.c +++ b/tools/testing/selftests/resctrl/resctrl_tests.c @@ -57,7 +57,7 @@ void tests_cleanup(void) int main(int argc, char **argv) { bool has_ben = false, mbm_test = true, mba_test = true, cmt_test = true; - int res, c, cpu_no = 1, span = 250, argc_new = argc, i, no_of_bits = 5; + int res, c, cpu_no = 1, span = 250, argc_new = argc, i, no_of_bits = 0; char *benchmark_cmd[BENCHMARK_ARGS], bw_report[64], bm_type[64]; char benchmark_cmd_area[BENCHMARK_ARGS][BENCHMARK_ARG_SIZE]; int ben_ind, ben_count; @@ -106,6 +106,10 @@ int main(int argc, char **argv) break; case 'n': no_of_bits = atoi(optarg); + if (no_of_bits <= 0) { + printf("Bail out! invalid argument for no_of_bits\n"); + return -1; + } break; case 'h': cmd_help(); @@ -188,7 +192,7 @@ int main(int argc, char **argv) printf("# Starting CMT test ...\n"); if (!has_ben) sprintf(benchmark_cmd[5], "%s", "cmt"); - res = cmt_resctrl_val(cpu_no, no_of_bits, benchmark_cmd); + res = cmt_resctrl_val(cpu_no, 5, benchmark_cmd); printf("%sok CMT: test\n", res ? "not " : ""); cmt_test_cleanup(); tests_run++;