diff options
Diffstat (limited to 'tools/testing/selftests/resctrl/cat_test.c')
| -rw-r--r-- | tools/testing/selftests/resctrl/cat_test.c | 41 |
1 files changed, 10 insertions, 31 deletions
diff --git a/tools/testing/selftests/resctrl/cat_test.c b/tools/testing/selftests/resctrl/cat_test.c index f00b622c1460..371a2f26dc47 100644 --- a/tools/testing/selftests/resctrl/cat_test.c +++ b/tools/testing/selftests/resctrl/cat_test.c @@ -14,42 +14,20 @@ #define RESULT_FILE_NAME "result_cat" #define NUM_OF_RUNS 5 -/* - * Minimum difference in LLC misses between a test with n+1 bits CBM to the - * test with n bits is MIN_DIFF_PERCENT_PER_BIT * (n - 1). With e.g. 5 vs 4 - * bits in the CBM mask, the minimum difference must be at least - * MIN_DIFF_PERCENT_PER_BIT * (4 - 1) = 3 percent. - * - * The relationship between number of used CBM bits and difference in LLC - * misses is not expected to be linear. With a small number of bits, the - * margin is smaller than with larger number of bits. For selftest purposes, - * however, linear approach is enough because ultimately only pass/fail - * decision has to be made and distinction between strong and stronger - * signal is irrelevant. - */ -#define MIN_DIFF_PERCENT_PER_BIT 1UL - static int show_results_info(__u64 sum_llc_val, int no_of_bits, unsigned long cache_span, - unsigned long min_diff_percent, unsigned long num_of_runs, bool platform, __s64 *prev_avg_llc_val) { __u64 avg_llc_val = 0; - float avg_diff; int ret = 0; avg_llc_val = sum_llc_val / num_of_runs; if (*prev_avg_llc_val) { - float delta = (__s64)(avg_llc_val - *prev_avg_llc_val); - - avg_diff = delta / *prev_avg_llc_val; - ret = platform && (avg_diff * 100) < (float)min_diff_percent; + ret = platform && (avg_llc_val < *prev_avg_llc_val); - ksft_print_msg("%s Check cache miss rate changed more than %.1f%%\n", - ret ? "Fail:" : "Pass:", (float)min_diff_percent); - - ksft_print_msg("Percent diff=%.1f\n", avg_diff * 100); + ksft_print_msg("%s Check cache miss rate increased\n", + ret ? "Fail:" : "Pass:"); } *prev_avg_llc_val = avg_llc_val; @@ -58,10 +36,10 @@ static int show_results_info(__u64 sum_llc_val, int no_of_bits, return ret; } -/* Remove the highest bit from CBM */ +/* Remove the highest bits from CBM */ static unsigned long next_mask(unsigned long current_mask) { - return current_mask & (current_mask >> 1); + return current_mask & (current_mask >> 2); } static int check_results(struct resctrl_val_param *param, const char *cache_type, @@ -112,7 +90,6 @@ static int check_results(struct resctrl_val_param *param, const char *cache_type ret = show_results_info(sum_llc_perf_miss, bits, alloc_size / 64, - MIN_DIFF_PERCENT_PER_BIT * (bits - 1), runs, get_vendor() == ARCH_INTEL, &prev_avg_llc_val); if (ret) @@ -158,7 +135,6 @@ static int cat_test(const struct resctrl_test *test, struct resctrl_val_param *param, size_t span, unsigned long current_mask) { - struct perf_event_read pe_read; struct perf_event_attr pea; cpu_set_t old_affinity; unsigned char *buf; @@ -181,8 +157,11 @@ static int cat_test(const struct resctrl_test *test, if (ret) goto reset_affinity; + ret = minimize_l2_occupancy(test, uparams, param); + if (ret) + goto reset_affinity; + perf_event_attr_initialize(&pea, PERF_COUNT_HW_CACHE_MISSES); - perf_event_initialize_read_format(&pe_read); pe_fd = perf_open(&pea, bm_pid, uparams->cpu); if (pe_fd < 0) { ret = -1; @@ -215,7 +194,7 @@ static int cat_test(const struct resctrl_test *test, fill_cache_read(buf, span, true); - ret = perf_event_measure(pe_fd, &pe_read, param->filename, bm_pid); + ret = perf_event_measure(pe_fd, param->filename, bm_pid); if (ret) goto free_buf; } |